NEEM DERIVATIVES BASED INTEGRATED PEST MANAGEMENT …

MANAGEMENT OF COTTON
Faculty of Agriculture
In Partial Fulfillment of the Requirement for the Degree of
DOCTOR OF PHILOSOPHY
2016
DECLARATION
I hereby declare that all the contents of the thesis, “Neem derivatives based Integrated Pest
Management of Cotton” are product of my own research and no part has been copied from any
published source (except the reference standard, mathematical or genetic models, equation, formulae,
protocols etc.). I further declare that this work has not been submitted for award of any other
diploma/degree. The university may take action if the information provided is found inaccurate at any
stage.
ACKNOWLEDGEMENTS
Up and above everything “All Glory is to Him”. The ALMIGHTY ALLAH, Who is
merciful and benevolent, and Whose bountiful blessings flourished my thoughts and thrived
my ambitions to have the cherish fruit of my modest efforts in the form of this manuscript. I
set my unfeigned and meek thanks before Him, Who created the universe and bestowed the
mankind with knowledge and wisdom to search for its secrets, favored and invigorated me
with the fortitude and capability to contribute a drop to the existing ocean of existing
knowledge.
My special praises after Almighty Allah with trembling lips and wet eyes stand for the
beloved Holy prophet, HAZRAT MUHAMMAD (Peace be upon Him), whose eternal
teachings would remain a source of guidance and inspiration for the mankind, whose
abundant blessings enabled me to perceive the higher ideas of life.
I acknowledge with deep reverence and sincerity and feel much pleasure in expressing my
heartiest gratitude to my supervisor, Prof. Dr. Masood Khan Khattak, Entomology
Department Faculty of Agriculture Gomal University, D.I. Khan for his dynamic and
affectionate supervision and whose inspiring attitude made it very easy to undertake this
project.
I wish to acknowledge my deep sense of profound gratitude to the worthy member of my
research supervisory panel Dr. Said Mir Khan, Dean, Faculty of Agriculture, Gomal
University, D.I Khan, Dr. Khalid Abdullah, Cotton Commissioner, Ministry of Textile
Industry Islamabad and Syed Agha Shah Hussain Chairman, Entomology Department
Faculty of Agriculture Gomal University, D.I. Khanfor their constructive criticism,
illuminating and inspiring guidance and perpetual encouragement throughout course of
study.
I feel great pleasure in expressing my sincerest thanks to Dr. Amir Hussain, Deputy District
Officer, Agriculture Extension Wing, Government of the Punjab, Dr. Jamshaid Iqbal
Assistant Professor of Entomology, Dr. Mamoon-ur-Rashid, Assistant Professor of
Entomology, Dr. Hafeez-ur-Rehman Assistant Professor of Entomology, Dr. Tahir Islam
Assistant Professor of Entomology, Dr. M. Faisal Shahzad Assistant Professor of
Entomology, Malik Muhammad Naeem Awan Assistant Professor of Entomology Gomal
University, D.I. Khan and Mr. Ghulam Murtaza Ph.D. Scholar of same University for their
cooperation and expert guidance. I am also thankful to Mr. Muhammad Ramzan Saheem, M.
A. (English) Computer Expert Department of Agriculture, Government of the Punjab, for his
expert computerization and suggestions regarding grammatical approach for my research
work and completion of this manuscript.
Sajjad Hussain
SUPERVISORY COMMITTEE
Department of Entomology
Cotton Commissioner
CHAIRMAN/ CONVENER Syed Agha Shah Hussain
DEAN Prof. Dr. Ejaz Ahmad Khan
CONTENTS
1.4.Integrated pest management (IPM) … … … 5
1.4.1. Biological control … … … 6
1.4.2. Importance of neem … … … 6
1.5. Aims and objectives … … … 7
2 REVIEW OF LITERATURE … … … 9
2.1. Integrated pest management (IPM) … … … 9
2.1.1. Chemical control … … … 10
2.1.2.1. Predator … … … 12
2.1.2.2. Parasitoids … … … 13
3.1.1. Soil Characteristics … … … 26
3.2.1. Weather Characteristics of the area … … … 27
3.3.Preparation of neem derivatives … … … 27
No. Title Page No.
i). Neem oil … … … 27
3.5. Insecticides used … … … 28
3.6. Spray equipment … … … 28
3.7. Laboratory condition … … … 28
4 Results and Discussions … … … 29
Study-1. Effect of neem derivatives alone, in
combination with bio-control agents and synthetic
insecticides on insect pest complex of cotton and its
yield.
… … … 29
1- Thrips … … … 33
2- Whitefly … … … 41
3- Jassid … … … 49
1- American bollworm … … … 56
2- Spotted bollworm … … … 57
3- Pink bollworm … … … 64
No. Title Page No.
combination with bio-control agents and
synthetic insecticides on per hectare
yield of seed cotton. … … … 66
4.5. Discussion … … … 68
response/distribution of jassid, whitefly and
spotted bollworms of cotton under laboratory
condition. … … … 71
derivatives and insecticide on the development
of spotted bollworm of cotton (No choice test)
under Laboratory condition. … … … 71
5.3.2. Spotted bollworms of cotton (Choice test) … … … 73
5.3.3. Toxic and growth inhibiting effect
(No choice test) … … … 73
settling response of … … … 74
derivatives and insecticide on the development of
spotted bollworms of cotton (No choice method) … … … 77
egg parasitization by Trichogramma chilonis
(indirect and direct effect). … … … 81
No. Title Page No.
different prey densities and consumption/
feeding of aphids by different instars of
Chrysoperla carnea. … … … 81
6.1. Abstract … … … 81
6.2. Introduction … … … 81
on egg parasitization by Trichogramma chilonis
(indirect and direct effect) … … … 82
6.3.2. Effect of neem derivatives and insecticide
on feeding rate of Chrysoperla carnea on aphids at
different prey densities and consumption/ feeding
of aphids by different instars of Chrysoperla
carnea … … … 83
Trichogramma chilonis on Helicoverpa eggs … … … 84
i. Indirect effect … … … 84
ii. Direct effect … … … 85
on feeding rate/consumption of aphids by
Chrysoperla carnea at different prey densities … … … 87
6.4.2. b- Effect of neem derivatives and insecticide
on feeding rate of Chrysoperla larvae
(different instars) on aphids. … … … 87
7 SUMMARY … … … 92
bio-control agents and synthetic insecticides on insect
pest complex of cotton and its yield. … … … 92
No. Title Page No.
bollworms of cotton under laboratory condition. … … … 92
Toxic and growth inhibiting effect of neem
derivatives and insecticide on the development of
spotted bollworm of cotton (No choice test) under
Laboratory condition. … … … 93
parasitization by Trichogramma chilonis (indirect
and direct effect). … … … 93
prey densities and consumption/feeding of aphids by
different instars of Chrysoperla carnea. … … … 94
Conclusions … … … 95
Suggestions … … … 95
4.1. Effect of neem derivatives alone, in combination with bio
control agents and synthetic insecticides on % population
reduction of thrips (1 st spray)
35
4.2. Effect of neem derivatives alone, in combination with bio-
reduction of thrips (2 nd
spray).
36
reduction of thrips (3 rd
spray)
37
reduction of thrips (4 th
spray).
38
reduction of thrips (5 th
spray)
39
reduction of whitefly (1 st spray)
43
reduction of whitefly (2 nd
spray)
44
45
spray)
reduction of whitefly (4 th
spray)
46
reduction of whitefly (5 th
spray)
47
reduction of jassid (1 st spray)
50
reduction of jassid (2 nd
spray)
51
reduction of jassid (3 rd
spray)
52
reduction of jassid (4 th
spray)
53
reduction of jassid (5 th
spray)
54
control agents and synthetic insecticides on % infestation of
American bollworm and spotted bollworm of cotton (3 rd
spray)
59
American bollworm and spotted bollworm of cotton (4 th
spray)
60
American bollworm and spotted bollworm of cotton (5 th
spray)
61
pink bollworm of cotton
control agents and synthetic insecticides on per hectare yield
of seed cotton
5.1. No of jassid, whiteflies and spotted bollworms settled on
untreated cotton leaves (control) vs. treated cotton leaves with
neem oil 1%, 2% and neem seed water extracts 2%, 4%. Chi
square test was performed at 95 percent confidence intervals
for the comparison of means
76
5.2. Toxic and growth inhibiting effect of neem derivatives and
insecticides on the development of spotted bollworms of
cotton. (No choice method)
6.1.A Indirect effect of neem derivatives and insecticide on the %
parasitism of by Trichogramma chilonis on Helicoverpa eggs
86
6.1.B Direct effect of neem derivatives and insecticide on the %
parasitism of by Trichogramma chilonis on Helicoverpa eggs
86
6.2.A Effect of neem derivatives and insecticide on feeding rate of
Chrysoperla larvae at different prey (aphids) densities
88
6.2.B Effect of neem derivatives and insecticide on feeding rate of
Chrysoperla larvae (different instars) on aphids
89
Fig. No. Title Page No.
4.1. Comparison of overall residual and treatments effect in 5 sprays
on % population reduction of thrips
40
on % population reduction of whitefly
48
on % population reduction of jassid
55
on % infestation of American bollworm of cotton
62
on % infestation of spotted bollworm of cotton
63
1
ABSTRACT
Field and laboratory experiments were conducted to see the effect of neem (Azadirachta
indica A. Juss) oil at 1, 2% and neem seed water extract at 2, 4% alone, in combination with
bio-control agents (Trichogramma chilonis and Chrysoperla carnea) with that of synthetic
chemicals viz. Actara 24WG (60gmha -1
), Imidacloprid 25%WP (625 gmha -1
), Fenpropathrin
)
against sucking insects i.e. whitefly (Bemisia tabaci Genn.), Jassid (Emrosca devastans
Dist.), thrips (Thrips tabaci Lind,) and chewing insects i.e. spotted bollworm (Earias
insulana Boisd.), american bollworm (Helicoverpa armigera Hubner) and pink bollworm
(Pectinophora gossypiella Saund.) of cotton (CIM-499). Crop was sprayed 5 times during the
cotton season. First spray was carried out 45 days after the date of sowing of crop and
repeated at an interval of 15 days of first spray and so on. Data of population dynamics of
sucking insects were recorded 24 hours before and then, 24, 168 and 336 hours after each
spray. The data for American and spotted bollworms infestation were recorded 168 and 336
hours after each spray while for Pectinophora gossypiella, the bolls were collected on 15 th
of
October 2005 and 2006 and dissected in the Laboratory to
calculate the infestation. For the yield of seed cotton, the picking was started when 50 %
bolls were open/ready for picking and was continued up to end of crop.
Overall, after synthetic insecticides, neem oil 2%+bio-control agents (Trichogramma chilonis
and Chrysoperla carnea) reduced significantly (p<0.05) % population of sucking insects
(thrips. whitefly and jassid) and % infestation of bollworms (American and spotted) of cotton
(168 hours after each spray). In case of pink bollworm, the bolls collected on 15 th
August,
found significant (p<0.05) on % damage/infestation of pink bollworm.The lowest mean %
damage (5.00%) recoded in the treatment treated with insecticides followed by N2+B (8.89
%), N1+B (10%) and W4+B (11.11%) which performed similar while the highest mean %
damage recorded in W2 with 22.78 % and N1 with 21.11 % which performed similar
compared with control (25.56%). Neem oil 2 % (14.44 %) and W4 (17.18%) gave similar
results.
Best results were received from the bolls collected during 15 th
August (8.83%) damage.
2
Maximum yield of seed cotton (1494 kg) was received in the plot treated with N2+B after
insecticide (1895 kg).
Neem derivatives at all tested concentrations have significant negative effect on settling
response of whitefly and jassid on cotton leaves as compare with that in their respective
control (untreated). Significantly lower numbers of test insects settled on neem derivatives
treated leaves except N1 and W2 in spotted bollworm as compare with that in their respective
control. Intensity of numbers of test insects settled on neem derivatives was lower at higher
concentrations of neem derivatives due to repellent/deterrent effect of neem derivatives.
Neem derivatives at all concentrations affected development (larvaeandpupae) of spotted
bollworm. Significantly minimum survival of larvae and maximum larval mortality and less
pupal formation was observed in Fenpropathrin 20EC application due to its toxic effect while
neem derivatives at higher concentration also affected survival of larvae and resulted into
larval mortality due to toxic effect of neem derivatives. Pupal formation was affected at
higher tested concentrations of neem derivatives due to growth regulating effect of neem
derivatives. Adult formation was not significantly affected by any treatment. The longest
larval and pupal duration were observed at higher concentrations of neem derivatives due to
growth regulating effect of neem derivatives.
In laboratory trials, all the neem derivatives (indirect effect) had non-significant differences
on the parasitism by Trichogramma chilonis on Helicoverpa eggs. Though, in the N2
treatment, % parasitization was significantly lower (P<0.05) than % parasitization in W2
treatment (indirect and direct effect). Adult emergence of T. chilonis was not affected by the
concentrations of neem derivatives. Percent parasitization of Helicoverpa eggs by T. chilonis
were inhibited (indirectand direct effect) in treatment of Proclaim 19EC (Insecticide) along
with adult emergence too due to toxic effect of Proclaim 19EC.
Neem derivatives at different concentrations and insecticide have significantly altered
feeding/consumption ability of predator (p<0.05). The highest % consumption of aphids by
Chrysoperla carnea was observed in the treatments of low concentrations of neem
derivatives while the lowest % consumption of aphids was noted in the treatments in
insecticide and higher concentrations of neem derivatives.
Aphid % consumption by Chrysoperla carnea at different prey (aphids) densities were
significantly different (p<0.05). Percent consumption of 75.87% was recorded when offered
3
when offered 32, 48, 64 and 80 aphids day -1
to predator.
different instars of Chrysoperlacarnea were found significant (P<0.05) on %
consumption/feeding of aphids.
The highest reduction in prey % consumption rate by Chrysoperla carnea was observed in
Imidacloprid 25%WP application (31.77%) followed by N2(69.19%) and W4 (70.61%)
while the lowest reduction in prey % consumption rate by Chrysoperla carnea was observed
in the treatment of N1 (91.77%) and W2 (91.44%) as compared with control (94.94%).
The highest % consumption of aphids was observed by the 2 nd
instar larvae (75.94%)
4
INTRODUCTION
Agriculture plays a central role in the economy of Pakistan. Its present contribution to
Pakistans Gross Domestic Product (GDP) is 21%. This sector is the largest employer,
absorbing 45% of the total labour force of the country. Nearly 62% of the countrys
population residing in rural areas is directly or indirectly dependent on agriculture for their
livelihood. It also plays a significant role in the overall socio-economic development of the
country by providing raw materials for the countrys major industries.
1.1. Importance of cotton
Cotton Gossypium hirsutum L. (family Malvaceae) is a Kharif fiber crop cultivated
throughout the country and plays a vital role in the Pakistan economy. Cotton feeds not
onlyraw material to the national textile and oil industry but also contributes 63.20% to the
export earnings of the country (Anonymous, 2002). Pakistan ranks third as an exporter of raw
cotton in the world (Ahmad, 1999). Its Lint is used in the textile industry for the preparation
of clothes while seed cotton (Benola) is a source of edible oil and contributes 69.5% share in
national oil production (Awan,1994). In Pakistan total area under cotton in 2003-2004 was
about 2989.3 thousand hectares with total production of 10047.7 thousand bales (1 bale =
375 lbs). In the Punjab Province, the area under cotton crop during 2003-2004 was 2386.8
thousand hectares with total production of 7702 thousand bales. The average production of
cotton in Pakistan during 2003-2004 was 572 kg A -1,
whereas the same was 549 kgA -1
( Anonymous, 2004). This production is still low as compared with few other cotton growing
countries because of certain limiting factor. Among those factors, the attack of insect pests is
the major one.
1.2. Major insect pests of cotton
A number of sucking and chewing (bollworm) insect pests species attack cotton crop from
emergence to maturity which feeds on green leaves, squares flowers, floral nectarines and
bolls. About 150 pests have been recorded on cotton crop (Shabbier, 1973). Among sucking
insects whitefly (Bemisia tabaci Genn.), jassid (Emrosca devastans Dist.), thrips (Thrips
5
tabaci Lind.), red cotton bug (Dysdercus koenigii Fab.) and mites (Tetranychus urticae) are
most important. Most serious bollworm pest species are Earias vittella, Earias insulana,
Pectinophora gossypiella, Helicoverpa armigera and Spodoptera litura. Attack of these pests
results into partial or complete failure of the crop. They not only reduce the yield but also
impair the quality of the fiber. It is estimated that in Pakistan 20 to 40 % of the total crop is
lost every year due to the insect pests (Zahoor, 1999) and could be as high as 50-60% in
some areas (Ahmed, 1980).
1.3. Management of cotton insect pests
Insectpests of cotton are mostly controlled by use of synthetic chemicals because of its quick
knock down effects. This approach is costly, non-specific, environment pollutant along with
health concern. This also encourages resistance development in insects. Widespread use of
chemical-based control programs has increased pest problems (Ahmad et al., 2001) by
disturbing the agro-ecosystem and destroying non-target and environment friendly organisms
including birds (Azeem, 2000). Due to the reasons, minor pests have become major and new
pests have appeared on cotton (Irshad, 2000). Moreover, at present country annual imports of
pesticides through registered firms alone is over Rs. 10 billion. About 90% of these were
being used on cotton (Ingram et al., 1989). Thus there is a great need to develop and integrate
alternate methods of pest control.
1.4.Integrated pest management (IPM)
Integrated pest management (IPM) approaches gain the popularity. Integrated pest
management, also known as Integrated Pest Control is a broad-based approach that integrates
practices for economic control of pests. IPM aims to suppress pest populations below the
economic injury level. IPM is a method of rationalizing pesticide use to prevent or delay the
resurgence of pest populations that had become resistant to pesticides, and to protect
beneficial insects (Alastair 2003). Today, concerns about pesticide residues in the food chain
and in the environment have led to alternative definitions that exclude the use of
conventional pesticides. Integrated pest management (IPM) is an ecosystem approach to crop
production and protection that combines different management strategies and practices to
grow healthy crops and minimize the use of pesticides. IPM therefore, utilizes the best mix of
control tactics for a given pest problem when compared with the crop yield, profit and safety
of other alternatives (Kenmore et al., 1985).
6
IPM technology has got wide scope in agriculture due to cost effective, environment friendly,
supportive to biodiversity, and resist to secondary outbreak of pest and diseases. IPM is the
intelligent selection and use of pest control actions that will ensure favorable economic,
ecological and sociological consequences. IPM is suited to all types of agriculture and
residential sites and commercial structures, lawn and turf areas, and home and community
gardens. Reliance on knowledge, experience, observation, and integration of multiple
techniques makes IPM a perfect fit for organic farming.
1.4.1. Biological control
Biological control of insect pests through biological means is most important component of
IPM. In broader sense, bio-control is use of living organisms to control unwanted living
organisms (pests). In other words, deliberate use of parasitoids and predators to maintain
pest population at level below those causing economic loss either by introducing a new bio-
agent into the environment of pest or by increasing effectiveness of those already present in
the field.
1.4.1. a. Predators andparasitoids
Predators and parasitoids are the first line of defense against sucking pests, bollworms of
cotton. Examples of predators are different species of spiders, dragon flies, damsel flies, lady
bird beetles, Chrysoperla species, birds etc. Parasitoids are the organisms which lay eggs in
or on the bodies of their hosts and complete their life cycles on host bodies as a result of
which hosts die. A parasitoid may be of different types depending on the host developmental
stage in or on which it completes its life cycle e.g. egg, larval, pupal, adult, egg-larval and
larval pupal parasitoids. Different species of parasitoids are of Trichogramma, Apanteles,
Bracon, Chelonus, Brachemeria, Pseudogonotopus etc.
1.4.2. Importance of neem
Bio-pesticides or Plant derived pesticides offer a more natural and environmentally friendly
approach to pest control than synthetic insecticides (Leatemia and Isman, 2004). More than
2400 plants species possess pest control properties. Among these plants, neem
(Azadirachtaindica A.Juss) has great potential for managing the insect pests. Neem oil,
extracts and even seed powder provides a good sources of insect pests control (Jacobson
1988). Neem extracts could influence almost 200 insect species of store grain; fruits,
7
vegetable, crops and ornamental plants. Neem products are medium to broad spectrum
pesticides for phytophagous insects. More than 100 chemical compounds are found in neem.
Among them Azadirachtin, salanine, malential are effective chemical compound (Jilani,
2002). Azadirachtin is the main component of neem responsible for toxic, repellent,
antifeedant, growth-inhibiting, oviposition-inhibiting and sterilizing effects against a variety
of insect pests species (Mordue and Nisbet, 2000; Martinez, 2002). Azadirachtin, a
tetranortriterpenoid from Azadirachta indica was reported to be a good insect growth
inhibitor of plant origin. It inhibits feeding and growth in a wide variety of insect taxa
including Lepidoptera.
Azatin EC tested on two species of green lace wings and it was found the neem product was
not toxic to eggs, larvae and adults, topically and residually (Schuster and Stansly, 2000).
As it is clear from above discussion, neem can also fit effectively into an IPM system with
conservation of beneficial bees, predators and parasitoids, mammals, and environment. Since
it is selective, with no or less negative impact on the ecosystems and works in association
with biological control organisms could be an interesting option for IPM.
Neem used in many forms did not record any deleterious effect on the development, fertility,
oviposition, fecundity or hatchability of the egg parasitoids, Trichogramma chilonis
(Balasubramanian and Regupathy, 1994; Jayaraj and Regupathy, 1999) either as neem oil or
any neem formulation like neemark at 0.3% or Achook at 0.3%. The selective action of neem
against insect pests without affecting the beneficial was also documented under field
condition on okra crop (Mishra and Mishra, 2002).
Although, neem is abundance in Pakistan but due to lack of technology, research and
knowledge, it is not usually used for insect/pests management. This dynamic tree needs to be
explored and popularized. Therefore, the present studies are undertaken with the objective to
evaluate the effect of neem products in IPM approach on insects/pests of cotton and their
predators and parasitoids.
1- To evaluate the antifeedant/deterrent and residual effects of neem derivatives; alone and
in combination with bio-control agents (Trichogramma chilonis and Chrysoperla
carnea), on sucking insects and bollworms complex and yield of cotton.
8
2- To study the effect of neem derivatives on distribution responses of sucking insects and
bollworm of cotton.
3- To assess the toxic and growth inhibiting effect of neem derivatives and insecticide on
the development of spotted bollworm of cotton.
4- To know the effect of neem derivatives and insecticide on parasitization by
Trichogramma chilonis.
5- To know effect of neem derivatives and insecticide on feeding rate of Chrysoperla
carnea on aphids at different prey densities and consumption/feeding of aphids by
different instars of Chrysoperla carnea.
9
REVIEW OF LITERATURE
Cotton (Gossypiumhirsute L.) plays a vital role in the economy of the Pakistan where
average yield per unit area is lower than many other cotton growing countries in spite of
ranking 6 th
in cotton production (Anonymous, 2000). Cotton is grown on an area of 3.0 m ha
with a production of over 10 million bales (Kifayatullah et al., 2005). Sucking and chewing
insects are two major groups that attack cotton crop and causes millions of losses annually.
About 15-20% of crop is damaged by sucking insects like whitefly, jassid, thrips and
chewing insects including spotted bollworm, American bollworm, and pink bollworm
damage every year (Alam et al., 1999). Many control measures are adopted for the
management of these insect/pests in cotton growing areas of the world. These measures
include cultivation of resistant varieties, use of IGRs, encouraging bio-control agents and use
of botanical and synthetic insecticides. In Pakistan, these insects are mostly controlled with
spraying of synthetic insecticides which are concern for health, environment and sustainable
agriculture. Recently, more environment friendly approaches are under practice such as IPM
including plant derivatives/bio-pesticides, bio-control agents (predators and parasitoids),
synthetic insecticides etc.
2.1. Integrated pest management (IPM)
Kenmore et al., 1985 reported that IPM utilizes the best mix of control tactics for a given
pest problem when compared with the crop yield, profit and safety of other alternatives.
Deole et al. 2000 has reported that neem formulations in moderate concentrations could be
considered a promising active ingredient to use in IPM programmes, and are more
compatible with Trichogramma species and Chrysoperla carnea than synthetic insecticides.
In fact, most of the chemicals tested by other researchers had long residual toxicity in these
bio- control agents.
Jilani and Akhtar, 2002 reported that in IPM, neem, predators and parasitoids have great
importance. Although neem has moderate repellant effect on bio-control agents but can be
incorporated in IPM program because these beneficial insects are killed when used with
chemical insecticides.
10
Alastair, O. (2003) defined IPM as “it is a method of rationalizing pesticide use to prevent or
delay the resurgence of pest populations that had become resistant to pesticides, and to
protect beneficial insects.
Rao et al. (2005) carried out an experiment in which they studied the existing status of the
management of Helicoverpa spp., especially H. armigera, through host plant resistance,
cultural practices i.e. intercropping, modification of sowing time, trap cropping and weeding,
biological (parasitoids, predators and pathogens) and chemical bio-pesticides and synthetic
insecticides control methods. Results were encouraging because of integrated pest
management (IPM) approaches against Helicoverpa spp.
Rajaram et al. (2006a) conducted trials in Tamil Nadu, India during 2003-04 and 2004-05 to
evaluate an integrated pest management (IPM) strategy for cotton cv. SVPR2. The
components of the IPM system were consisted of, resistant cotton cultivar, intercropping with
cowpea, sunflower, black gram, green gram and okra; trap/border cropping with castor and
maize/sorghum, soil application of recommended N rate, along with split application, bird
perching, mechanical collection and destruction of infested plant parts and pest life stages,
release of Trichogramma chilonis at 5 cc/release per week and Chrysoperla carnea at 1 lakh
grubs/release (based on moth activity), neem oil at 3%, neem-based spraying with HaNPV at
500 LE/ha and SINPV at 250 LE/ha, installation of pheromone traps at 12/ha and yellow
sticky traps at 50/ha; and neem-based use of recommended insecticides. Leafhopper
(Amrasca sp.) incidence was 1.4/plant and 2.2/plant in IPM plots and non-IPM plots
respectively. Bollworm (Helicoverpa sp.) resulted into lower (11-14%) damage in IPM plots
than non-IPM plots (25-29% damage). Stem weevil (Pempherulus affinis) caused infestation
(15.56%) of the crops in the IPM plot while 25% of the plants in non-IPM plots. Yield was
recorded as 145 kg ha -1
in IPM plot, while 100 kg ha -1
in non IPM plot.
2.1.1. Chemical control
Like the most other countries, pest control in Pakistan, is based largely on the chemical
insecticides. Pesticides have played a significant role in the food security, in Pakistan.
Chemical methods of pest control are very effective in combating serious pest infestation.
Hamed et al. (1997) found confidor (imidacloprid) 35 EC to be very effective against the
jassid with 89% mortality.
11
Gul (1998) tested five insecticides, against jassid on „okra and found imidacloprid 200 SL,
to be effective for a long time, as compared to other insecticides, like dimethoate 40 EC,
dichlorvas 100 EC, methyl-parathion 50 EC and monocrotophos +alpha-cypermethrin 42 EC.
Kumar and Dikshit, 2001 reported that imidacloprid, a nitro guanidine, is systemic in nature,
and has a wide spectrum of activity. Imidacloprid acts as an agonist at the insect nicotinic 25
acetylcholine receptor (nAChR). It has an anti-feedant activity against the adults, and has a
limited translaminar and contact activity, as a short residual, foliar spray.
Saleem et al. (2001) reported that confidor 200 SL effectively controlled the jassid up to 7
days, after the spray.
Suh et al (2000) investigated effect of insecticides on emergence, adult survival, and fitness
parameters of Trichogramma exiguum. Insecticides tested were lambda cyhalothrin,
cypermethrin, thiodicarb, profenophos, spinosad, methoxyfenozide, and tebufenozide. All
insecticides, with the exception of methoxyfenozide and tebufenozide, adversely affected
Trichogramma emergence from Helicoverpa zea (Boddie) host eggs when exposed at
different preimaginal stages of development (larval, prepupal, or pupal). However, the mean
life span of emerged T. exiguum females significantly varied among insecticides, and was
significantly affected by the developmental stage when treated.
In field trails, Ulaganathan et al. (2004) evaluated the efficacy of different insecticidal spray
schedules against the sucking pests of cotton viz. Jassid, whiteflies, thrips and aphids. The
spray schedule comprising of six rounds of new synthetic insecticide molecules (acetamiprid,
imidacloprid, beta-cyfluthrin, spinosad, bifenthrin/indoxacarb and lambda-cyhalothrin) was
effective in reduction of jassid, whitefly and thrips populations, however, the population of
aphid build up severely. One application of ten to eleven rounds of insecticides (synthetic)
was effective against jassid and thrips only. Insecticidal mixtures against whitefly at its peak
population were effective but could not continue for a long run. Repeat spray of neem was
effective against sucking pests, but alternate spray of neem and Bt (Bacillus thuringiensis)
could not control any of these pests.
Singh et al. (2005) evaluated the efficacy of imidacloprid and acetamiprid and compared it
with methyl demeton for the control of jassid, on „okra. The data revealed that imidacloprid
formulation, confidor 350 SC @ 75 ml/ha, was the most effective 26 treatments in reducing
12
the jassid-incidence to a seasonal mean of 10.65, per 5 plants, and recorded the maximum
fruit yield of 87.4 q/ha, followed by Confidor 200 SL at 100 ml/ha, with a seasonal mean of
12.72 jassid/5 plants, and a fruit yield 81 q/ha.
2.1.2. Biological control / Bio- control agents
2.1.2.1. Predator
Zaki et al. 1999breported that insecticides, earlier considered as the backbone in crop
protection, have become subordinate to other control methods, such as bio-control which has
gained more credibility in the last decades but, the effectiveness of bio-agents has been
jeopardized by these insecticides. The sensitivity of C.carnea to insecticides differs from
compound to compound.
McEwen et al. 2001 reported that common green lacewing, Chrysoperla carnea (Stephens)
(Neuroptera: Chrysopidae) is one of the most common arthropod predators with a wide prey
range including aphids, eggs and neonates of lepidopteron insects, scales, whiteflies, mites,
and other soft bodied insects. It has long been considered as an important component for pest
management programs worldwide due to its wide prey range and geographical distribution,
resistance/tolerance to pesticides, voracious larval feeding capacity as well as commercial
availability.
Gautam et al. (2002) made an experiment in which they concluded that the common green
lacewing (Chrysoperla carnea) can be used in augmentation program for sustainable crop
pest suppression. A variety of soft-bodied insects and mites found on various agro-
ecosystems is attacked by it. The predatory potential of the predator is different depending on
the prey species. For example, a single larva of C. carnea in the course of its development
can destroy 216-950 nymphs and adults of aphids, 510.8 pupae of white flies, 160-200 eggs
of Helicoverpa (Heliothis armigera), 147 maggots of Drosophila melanogaster and 350 eggs
of Corcyra cephalonica. In the field, it has been demonstrated that the potential for utilizing
chrysopids for biological control with different types of manipulation on various crops pests
such as cotton, apple, aborigine, potato, cabbage, tomato, pomegranate and safflower,
Chrysoperla carnea can resist, tolerate the insecticides like endosulfan, monocrotophos,
fenvalerate, permethrin, pirimicarb, carbaryl, carbosulfan, Bacillus thuringiensis, botanicals
(nicotine, neem, rotenone, etc.) and novel insecticides like nitenpyram, imidacloprid and
acetamiprid.
13
2.1.2.2. Parasitoids
Mohyuddin and Muhammad, 1985 reported that in Pakistan, Trichogramma species has been
reported from various host species including Acigona steniellus Hamp, Chilo infuscatellus
Snellen, Chilopartellus Swin, Helicoverpa armigera Hub and Emmalocera depressella Swin.
Thakur and Pawar (2000) conducted experiment to test two neem-based insecticides (3g
Achook/litre and 2 ml Neemactin/litre), two bio-pesticides [1 g Halt (cypermethrin)/litre] and
1ml. Dipel (Btk)/litre], and endosulfan (1.5 ml/litre) in the laboratory for their relative
toxicity to newly emerged adults of Trichogramma chilonis. Results revealed that neem-
based pesticides and bio-pesticides were harmless while endosulfan was slightly toxic to egg
parasitoid.
El-Wakeil (2003) reported that during the past three decades, Trichogramma spp. wasps have
been evaluated as biological control agents for heliothine pest suppression in cotton.
Panchbhai et al. (2004) studied the efficacy of T. chilonis (1.5 lakh eggs/ha) and C. carnea (2
second instar larvae/plant or 4 eggs/plant) at different rates of releases independently and
together in comparison to Neem Seed extract at 5% and endosulfan at 0.07% against
Helicoverpa armigera, Earias vittella and Pectinophora gossypiella on cotton. The results
indicated that combined releases of T. chilonis @ 1.5 lakh parasitized eggs ha-1 with
different rates of Chrysoperla carnea were comparable with recommended insecticide
endosulfan at 0.07% and proved to be effective in reduction of infestation by bollworm
complex in squares, flowers, green bolls and open bolls, loculi damage by pink bollworm and
% bad seed cotton, thus resulting into a higher yield of seed cotton.
2.1.3. Neem derivatives
Gill and Lewis (1971) noted azadirachtin (compound of neem) as systemic feeding
deterrence for insects. Azadirachtin not only kills pests, but it breaks life cycles, deters
feeding, disturb hatching, and interrupt ecdysis or any combination of these processes as
well.
Jilani and Malik (1973) reported that water and ethanol extracts of neem leaves and seed
possess repellant action against adult and larvae of red flour beetle (Tribolium castaneum
Herbst.), larvae of khapra beetle (Trogoderma granarium Everts) and adult of lesser grain
borer (Rhyzopertha dominica F).
14
Monique et al. (1983) investigated the effect of azadirachtin against various lepidopterous
larvae in diet. They found that the taste responses of the larvae have feeding activity. A
neuro-physiological examination (The sensory input affecting feeding) of the responses of
the two sensilla styloconica on each of the maxillae was conducted and it was found that
Azadirachtin reduced feeding and imparted development in all species tested. In some
species it stimulated a specific deterrent neuron. While in others, it inhibited the continuity of
neurons, which signify phago-stimulants. Induction of food preference was tested at
behavioral and sensory levels. Azadirachtin was more sensitive on oligophagous species than
polyphagous species.
Jillani and Ullah (1984) described that neem with its insecticidal properties is native to
Pakistan and India and it is also grown in some African countries. Neem cultivation has
gained attention in developed countries during the last decades. People either place leaves of
neem with grains before storage, or neem fruits are crushed against the inside walls of mud
bin before grains are stored in Pakistan, especially in the Punjab and Sind provinces. To
protect store grains from the attack of stored grain insect pests, neem leaves are sometimes
spread in layers when grains are stored in Jute bags.
Ahmed and Grainge (1986) stated that neem extracts are usually safe for beneficial
organisms - bees, predators, parasitoids, mammals - and also environment friendly.
Singh and Singh (1985) found that Treatment of water extracts of de-oiled neem kernel
disturbed the growth of first and third instars larvae of Trogoderma granarium.
In the laboratory experiments, Singh and Kataria (1986) observed that extracts of de- oiled
neem kernel powder mixed with wheat at 0.06%, 0.125%, 0.25%, 0.5%, 1%and 2.0%
affected the egg hatching of Trogoderma granarium and all larvae died in the first instar
before the eleventh day after hatching while all those in the control had reached third instars
by this time.
Blaney et al. (1990) found that two other compounds i.e. salanin and nimbin, present in seed
extract, exhibited an entirely different mode of action than azadirachtin.
Saleem and Matter (1991) observed that the neem oil acted as temporary repellent against the
predatory staphylinid beetle, Paederus alfierii, the coccinellid, C. undecimpunctata and the
15
lacewing, Chrysoperla carnea in cotton but otherwise neem oil had no adverse effect on
these predators of Spodoptera littoralis.
Isman et al. (1992) reported that neem had no detrimental effects on predatory coccinellid,
chrysopids and syrphids.
Tahir et al. (1992) found that Darek fruit powder was more effective in reducing damage to
chickpea by pod borer than neem oil compared with control. Similarly, by the use of a
commercial formulation of neem (RD-Replin), aphid was deterred successfully.
Bhuvaneshwari et al. (1993) reported the safety of neem oil 50 EC and NSKE at different
concentrations to grubs of C. carnea.
Yashida and Toscano (1994) investigated that the relative consumption rate up to 25% of the
control of Heliothis virescens larvae treated with azadirachtin was reduced, having properties
of the lowest assimilation efficiency of all natural insecticides tested.
Khorkhordin and Mironova (1996) concluded that neem formulation at high concentrations
has slight effect on parasitism and adult emergence of Trichogramma japonicum (egg
parasite).
Mansoor et al. (1996) conducted an experiment to observe the effect of neem samples, neem
oil, fenoxycarb and NK-I 35120 at 5.0, 1.0, 0.64 and 0.25%, respectively, against sucking
insect pest complex of cotton under natural, semi-natural and controlled conditions in
Faisalabad, Pakistan. Neem sample gave significant control of jassids (Amrasca devastans),
thrips (Thrips tabaci) and aphids (Aphis gossypii), in the laboratory and field experiments.
The application of NK-I 35120 and fenoxycarb remained ineffective on sucking insect pests
under field conditions. Nevertheless, in the laboratory, the moulting duration was prolonged
in case of all the insects.
Srinivasa Babu et al. (1996) studied the effects of neem-based commercial insecticides
(Repelin and Neemguard) on Trichogramma australicum in laboratory and field conditions.
They concluded that both the insecticides were relatively safe at lower concentrations but
higher concentrations adversely affected the parasitoids both in laboratory and in field.
Hermann et al. (1997) reported that NeemAzal T/S and NeemAzal-F have no negative effect
on the predacious efficiency of Chrysoperla carnea except longevity of larval instars.
16
In Faisalabad, Pakistan Parvez et al. (1998) evaluated the efficacy of some neem derivatives,
i.e. neem samples at 1 and 2%, neem oil at 5 and 6%, neem seed kernel extract at 3 and 4%
NSKE, and 0.05% nuvacron (Standard) against the cotton jassid Amrasca devastans [A.
biguttula biguttula]. Jassid population on cotton was significantly reduced by neem oil, neem
samples and NSKE, indicating their repellent and phago-deterrent properties. The effect was
dose-dependent. In okra, neem oil at 5 and 6% was the most effective in controlling cotton
jassid.
Raja et al. (1998) reported about the slight toxicity of neem based pesticides and bio-
pesticides to egg parasitoids. They further recommended that in IPM program neem product
in controlled concentrations and in combination with natural enemies having resistant to bio-
pesticides be used.
In field experiment, Gupta et al. (1999) tested the evaluation of the bio efficacy of neem
products from Azadirachta indica against cotton bollworms, viz., Earias spp., Pectinophora
gossypiella (Saunders) and Helicoverpa [Heliothisarmigera (Hubn)], and their impact on
whitefly, (Bemisia tabaci Genn.). Application of neem alone or in combination with Bt
formulation or broad spectrum conventional insecticides failed to check the incidence of
bollworms.
Sarode and Sonalka (1999a) reported that neem seed extract was also found safe to C. carnea
in comparison to nine insecticidal products where chlorpyrifos, deltamethrin and
cypermethrin were found highly toxic to Chrysoperla carnea.
Gahukar (2000) said that Products derived from leaves and kernels of neem
(Azadirachtaindica A. Juss) are becoming popular in plant protection programs, mainly
owing to the several undesirable effects of synthetic pesticides. Neem products work as
antifeedant, toxicological, repellent, sterility inducing or insect growth inhibiting against a
variety of insect pests species.
In field the experiment in India, Suganthy (2000) found that neem as a first and fourth spray
reduced the oviposition of Helicoverpa armigera significantly, registering 37.00% and
36.79% reduction in oviposition as compared to that in the control.
Ma et al. (2000a) conducted an experiment in which they applied environmentally friendly
compounds to cotton plants in order to determine the prevention of egg laying by bollworm
17
moths. The said researchers tested an oil extract of neem tree and a commercially available
product (Envirofeast) against bollworm grown at Dalby, Australia showing that neem oil was
more effective in reducing the oviposition by bollworms in cotton.
Ma et al. (2000b) evaluated the effect of bio-pesticides and chemicals on cotton during its
reproductive phase against the bollworms Helicoverpa armigera (Hubner) and H. puntigera
Wallengren and as well as their predators at Dalby, Queensland, Australia. Neem-seed
extract (azadirachtin) (@ 30g, 60g and 90g per hectare) resulted into moderate rate-
dependent control of the test insect while Talstar EC (bifenthrin) achieved the best results.
Predators (lady beetles, lacewings, spiders and bugs) were not sensitive to Azadirachtin.
Azadirachtin-treated plots gave higher yield of seed cotton as compared to the control.
Ma et al. (2000c) conducted studies on second instar larvae of Helicoverpa armigera
(Hubner) fed for 4 days on potted cotton plants (Gossypium hirsutum L.) sprayed with 3%
azadirachtin emulsifiable concentrate. High mortality of larvae was observed on both treated
plants and controls. To assess the physiological effects caused by post digestion of
azadirachtin-treated cotton, surviving larvae were transferred to an untreated artificial diet.
All treatments showed growth retardation reduced larval and pupal weight and prolongation
of development. Growth inhibition by azadirachtin was dose-dependent.
Patel et al. (2000) carried out their field studies to evaluate Bacillus thuringiensis sub sp.
kurstaki (Btk; Cutlass, Delfin, Bactec) and neem (Azadirachtin) for the management of
cotton bollworms (Helicoverpa armigera, Earias vittella and Pectinophora gossypiella).
Delfin and Bactec at 1 kg ha -1
had similar effect as the chemical insecticide-treated control in
protecting the fruiting bodies (bud and green boll) of the cotton hybrid 6. Neem was less
effective than Btk but better than the untreated control/check plot. Chemical insecticide
treated plot gave the highest yield of seed cotton followed by Btk, neem and untreated check.
They were found less toxic to predators such as green lacewings (Chrysopa scelestes
[Brinckochrysa scelestes]) and (Mallada boninensis), coccinellid (Menochilus sexmaculatus
[Cheilomenes sexmaculata] and Coccinella septempunctata) and predatory spiders (Oxypes
sp. and Lycosa sp.) in cotton fields compared to chemical and neem treatments.
Gurusamy et al. (2000) made field experiments on the effect of biological extracts Pongamia
pinnata leaf, Azadirachta indica leaf, Morinda sp. leaf, cow dung and Prosopis sp. leaf on
pest incidence, yield and growth of cotton cv. MCU 10. Neem leaf extract was the most
18
effective treatment in increasing crop growth parameters like plant height (54.8 cm), leaf area
index (2.16) and dry matter production (2079 kg ha -1
), compared to control (no treatment;
43.6 cm, 1.62 and 1728kg ha -1
, respectively) and also significantly reduced jassid (Amrasca
biguttula) and bollworm (Helicoverpa armigera) populations with the highest Yield (426 kg
ha -1
).
Mohammad et al. (2000) compared the effect of a neem product (phytopesticide FWB) with
perfekthion (dimethoate) against sucking insect pests (jassid, thrips, aphids and whiteflies) of
cotton. Perfekthion was more toxic with its effect for 4 days only while the neem product
(FWB) was relatively less toxic with its effect for 6 days. Besides, neem product was safer
and non-polluting.
Moazzam et al. (2000) made a trial in which cotton leaf curl virus (CLCuV) susceptible
cotton (cv. S-12) plants, sown in plastic pots, were sprayed at 2-3-leaf stage with 3
concentrations of neem oil (0.1, 0.5 and 1%), fresh neem leaves and seed (10 g each)
extracts, neem flavonoids (glycosides and aglycone, both at 3% concentration in water or
ethanol), or nimbokil (0.5% in water at pH 6.5) on both sides of leaf surface., 10 viruliferous
whiteflies (Bemisia tabaci) were released thirty minutes after spraying on each cotton plant,
and the plants were covered with plastic cages. In another experiment, crushed neem seeds
and leaves (3 g/pot) were applied to the top soil layer 7 days after seed germination and the
plants were watered. After 15 days, 10 viruliferous B. tabaci were released on each cotton
plant, and the plants were covered with plastic cages. In the said experiments, whiteflies were
manually removed after 72 h using a camel hair brush. Complete inhibition of disease
transmission (100%) among treatments was observed by only foliar application of neem leaf
extract and 1% neem oil. Neem seed extract resulted into 80% reduction of CLCuV
transmission. This was similar with application of neem flavonoids in water and 0.5% neem
oil. Only one plant developed severe CLCuV symptoms, in soil application.
Babu et al. (2000) used methanolic neem (Azadirachta indica A. Juss) seed kernel extracts
(NSKE), Pongamia pinnata L. seed extracts (PPSE) and Vitex negundo L. leaf extracts
(VNLE) to cotton leaves and fed to cotton bollworm (Helicoverpa armigera) to assess their
effects on feeding, survival and fecundity. Neem Seed Kernel Extracts was highly effective
individually against the test insect as compared with PPSE and VNLE. Mixture of the
extracts enhanced feeding deterrence and mortality and decreased fecundity of Helicoverpa
19
armigera and also gave initiation to dose-dependent changes resulting in delayed
metamorphosis with larval-pupal intermediates, abnormal adults and finally death.
In laboratory studies, Khattak et al. (2000) found neem at 10,000 ppm in acetone affected the
distribution of maize weevils on treated and untreated corn kernel.
Khattak et al. 2001 found that neem oil at 100, 1000 and 10000 ppm neither affected
oviposition and settling of the Anisopteramalus calandrae (Howard) nor these concentrations
of neem oil showed any toxic effect against the test insect (parasitoids).
Praveen et al. (2001) evaluated the effectiveness of different biological control agents against
the major insect pests of okra, i.e. leafhopper (Amrasca biguttula), sweet potato whitefly
(Bemisia tabaci), cotton aphid (Aphis gossypii), and the fruit-boring insects (Helicoverpa
armigera and Earias vitella). They observed that the release of Chrysoperla carnea (25000
larvae/ha)+Econeem 0.3% (0.5 l/ha) at 15-day intervals (for three times) starting from 45
days after sowing was found effective in reducing the population of sucking pests and the
fruit-borers as well. The 8.61% fruit damage by H. armigera and 9.21% by E. vitella were
significantly lower than the 22.56% and 22.60% in the respective control.
Mann et al. (2001a) studied the effectiveness of Neemazal (1%), Rakshak Gold (1%) and
Neem powder (0.5%), each at 0.5, 1 or 2 ton/ha (high potency neem-based insecticides)
against Bemisia tabaci during flowering and its impact on management of other insect pest
complex (Amrasca biguttula, Aphis gossypii and Helicoverpa armigera) on cotton
(Gossypium spp.). Neemazal and Rakshak Gold @ 2 litres/ha needed only 4 sprays during 48
days of economic damage period of Bemisia tabaci and to suppress B. tabaci below the
economic threshold level (ETL), their effect persisted for 6-12 days. At higher-doses, the
populations of Aphis gossypii, Amrasca biguttula and bollworm damage also remained
significantly low.
Mann et al. (2001b) made experiments on the evaluation of the effects of neem formulations
based on azadirachtin content (NeemAzal, Rakshak Gold and ICIPE Neem at 1% each) and
triazophos against beneficial arthropods (including parasitoids: Encarsia transvena, E.
luteaand predators: spiders, coccinellid and Chrysoperla carnea) in the cotton agro
ecosystem. In the treatment with 2 litres Rakshak Gold/ha, Parasitism of Bemisia tabaci by
Encarsia spp. was minimum (4.1%) and was at par with the control (4.5%). However,
triazophos gave very strong detrimental effects and resulted into 0.86% parasitism. The
20
number of spiders per 15 plants was significantly maximum (5.00) in the treatment with 1
litre NeemAzal/ha than that of the control (3.00) whereas, triazophos proved highly toxic
(0.33 spiders per 15 plants). Upon treatment with NeemAzal at 2 litres/ha, the population of
coccinellid per 15 plants was minimum (3.32). However, triazophos proved highly toxic,
resulting in 0.66 coccinellid per 15 plants. Chrysopids per 15 plants were minimum (1.40)
upon treatment with 2 litres Rakshak Gold/ha was significantly lower than that of the control
(7.0).
Sharma et al. (2001) carried out a study in Maharashtra, India in 1999, to validate an IPM
module. The pest scenario and the strategies were evaluated under three regimes: (IPM
practices, non-IPM (farmers' practices) and roving survey). The module comprised of
planting of maize+cowpea as border crop, Setaria as intercrop and release of egg parasitoid,
5% neem seed kernel extract (NSKE), HaNPV 250 LE/ha, 50 g carbosulfan/kg, pheromone
Trichocard (3 times), pheromone traps (2 per acre) and dimethoate spray. The population of
sucking pest viz. Aphis gossypii, Empoasca sp., Thrips tabaci and Bemisia tabaci and %age
damage due to bollworms was low under IPM compared to non-IPM. A low disease
incidence did not need any management interventions. At both the villages (Sonkhed (17.5
q/ha) and Dongargaon (12.5 q/ha), the seed cotton yield was higher than that obtained upon
treatment with farmers' practices (7.5 q/ha and 6.9 q/ha, respectively). The reduced use of
pesticides gave higher net returns, environmental safety and conservation of beneficial
insects. At both the villages, farmers field schools and adoption of the technology made
farmers confident decision makers.
Kulat et al. (2001) reported that population buildup of H. armigera was reduced by treating
the crop with the leaf extracts of Nicotiana tabacum, seed extract of P. glanbra and indiara,
and neem seed kernel extract as compared to the control.
Gupta 2001(a) evaluated Godrej Achook at 1500 ppm, Neemazal at 50 000 ppm and Neem
Jeevan Triguard at 60 000 ppm (neem products) against cotton bollworm (Helicoverpa
armigera). He also made experiment to test the endosulfan at 35% EC at 2000 ml/ha; Neem
Jeevan at 300 ppm (0.4 and 0.6%); Neem Jeevan Triguard at 60 000 ppm (at 0.1 and 0.15%);
and Nimbecidine at 300 ppm (at 0.4 and 0.6%) in the field against Helicoverpa armigera.
Laboratory studies showed that in all neem treatments, insect development was decreased
and mortality was caused. Rich fractioned Azadirachtin possessed insecticidal and
antifeedant activities compared to fractions with lower Azadirachtin concentration. Field
21
studies showed that Neemazal at 50 000 ppm and Neem Jeevan at 60 000 ppm being
effective against the pest, can be used as alternatives to chemical insecticides.
Tang et al. (2002) stated that Neem extracts are usually safe for beneficial organisms
(predators and parasitoids) and for the environment.
Rawale et al. (2002) in their studies determined that reduction in insect pest infestation and
increase in seed cotton yield, all the insecticidal treatments showed superiority over control
and herbal product (neem seed extract). Polytrin C-44 @ 0.04%, after 2nd and 4th spraying,
resulted the lowest bollworm infestation in bolls and lowest (6.01%) loculi infestation at
harvest and lowest (3.92%) %age stained lint and the highest (11.51q ha-1) seed cotton yield.
Minimum bollworm infestation in fruiting bodies and boll infestation (16.61%) at harvest
was shown by plots sprayed with chlorpyriphos at 0.03 per cent after 1st and 3rd spraying.
The performance of profenophos 0.10% and 5% neem seed extract (N.S.E.) was poor against
the bollworms.
Martinez (2002) Mordue and Nisbet (2000), Ahmed and Grainge (1986), Schmutterer (1990),
reported that Azadirachtin (a chemical complex found in seeds of neem, Azadirachta indica
A. Juss), is the main component responsible for the toxic, repellent, anti-feedant, growth-
inhibiting, oviposition-inhibiting and sterilizing effects in insects.
Lyons et al. (2003) offered neem treated eggs of Ephestia kuehniellu in shell vials to single
females of Trichogramma minutum for parasitization. The eggs were fixed with adhesive to
strips and held until all parasitoids had emerged from them. Azatin, Neem EC (experiment
formul. 4.6% aza) and pure aza were tested at concentrations of 50 g and 500 g ha -1
. At 50 g
no significant effect was observed, at 500 g ha -1
Azatin and Neem EC reduced the
female survival by 64% and 40% respectively whereas pure aza showed no effect. Likewise,
at 500 g ha -1
the number of parasitized eggs was reduced by 89% by Azatin, 29% by Neem
EC but not reduced by aza. The parasitoid's development success was reduced by all
treatments.
Singh et al. (2003) tested the efficacy of neem based pesticides against cotton jassid (A.
biguttulla). The treatments comprised endosulfan @ 0.07%, Achook @ 0.7%, Neemarin @
0.7%, neem seed kernel extract (NSKE) @ 1%, NSKE @ 3% and a control. Endosulfan,
followed by Achook and NSKE @ 3% was the most effective in controlling the okra jassid.
Achook-treated plots resulted into the highest yield of 50.06 q/ha and was significantly
22
surpassed other treatments. However, on the basis of cost benefit ratio, NSKE @ 3% ranked
first (1:10.70), followed by endosulfan (1:10.07).
Sundararajan (2003) made an experiment in which aqueous leaf extracts of three species of
plants (Vitex negundo, Tagetes indica and Parthenium hysterophorus) were tested for their
biological activities against the larvae of Helicoverpa armigera by applying dipping method
of the leaf extracts @ 2%, 4%, 6%, 8% and 10% concentrations on young tomato leaves. The
mortality of larvae of more than 50% at 8% and 10% treatments was observed in all the
extracts. Among the leaf extracts tested, V. negundo showed high rate of mortality (85%) at
10%. In all the extracts at 10% level, a reduction in the rate of food consumption and growth
was observed in the fourth instar larvae of H. armigera after 48 hours of treatments.
Gupta et al. (2004) tested 15000 ppm Godrej, 50,000 ppm Neemazal and 60,000 ppm Neem
Jeevan Triguard against Helicoverpa armigera reared on artificial diet. The formulations
(azadirachtin-rich content) were highly toxic to H. armigera. Both Neemazal and Neem
Jeevan Triguard at the concentration of 0.15% showed the best antifeedant effects (73%).
The juvenomimetic effects against H. armigera were studied too. The developmental time
was significantly longer for all the formulations (azadirachtin-rich content) compared to the
control. Larvae which were treated with Neemazal and Neem Jeevan Triguard required 35.8
and 11.1% additional days respectively to reach the pupal stage compared with the control.
Azadirachtin resulted into deformities in the developing larvae, pupae and adults. The most
obvious morphogenetic effects that appeared were larval-pupal intermediates, deformed
pupae, and adults with frizzled or curved wings, weak and smaller in size. Inhibition and
disruption of moulting were observed at 0.025 and 0.05% azadirachtin, though, larval-pupal
intermediates and abnormal pupae were also commonly observed. The larval-pupal
intermediates were observed at moderate concentrations (0.075% of Neemazal and 0.10% of
Neem Jeevan Triguard) & resulting into 18.7% of the larval-pupal intermediates.
Thesurvived pupae either unsuccessful to develop further or if developed into adults, died
during eclosion having frizzled or curled wings.
Koul et al. 2004 reported that the compounds present in the neem oil are reported as strong
antifeedant and growth inhibitors against lepidopteron larvae.
Monteiro et al. (2004) studied the effects of aqueous extracts of neem (Azadirachta indica A.
Juss) seed powder on the development, survival and fecundity of Aphis gossypii. Treatments
23
consisted of neem seed powder at 23.8, 122.0, 410.0 and 1,410.0 mg/100 ml. of distilled
water. Mortality rate of aphids during the nymphal development maintained on cotton leaf
discs treated with the two highest concentrations were 60.0% and 100.0%, respectively. With
the exception of the highest concentration (1,410.0 mg/100 ml.), neem concentrations did not
extend the aphids' development period. The result showed that net reproductive rate (R0) was
found as 35.0 nymphs/female for control aphids and 0.0 nymph/female when the group of
females was exposed to neem seed powder at 1,410.0 mg/100 ml since birth. The aqueous
extract of neem seeds is efficient against the aphid (Aphis gossypii) resulting into nymph
mortality and reduction into their survival period and fecundity.
Opender et al. 2004 assessed the biological activity of azadirachtin, nimbocinol, azadiradione
and salanin (isolated from Azadirachta indica) alone and in combination against the cotton
bollworm, Helicoverpa armigera and cluster caterpillar, Spodoptera litura. Nimbocinol
resulted into growth inhibitory activity in artificial diet bioassays with 82.4 and 92.2 mg kg-1
concentrations inhibiting growth by 50% in H. armigera and S. litura, respectively. Said
efficacy was almost comparative to azadiradione (EC50=109.6 and 102.1 mg kg-1) and
salanin (EC50=72.2 and 70.2 mg kg-1). Azadirachtin proved the most active neem
allelochemical against both insect species. In feeding experiments (nutritional analysis), the
efficiency of conversion of ingested food (ECI) was reduced by nimbocinol and azadiradione
indicating toxicity rather than antifeedant effects. In a combination, when azadirachtin was
present in a mixture, its efficacy was always dominated and EC50 values did not deviate
much from the individual efficacy of azadirachtin (0.23 and 0.21 mg kg-1) against H.
armigera and S. litura larvae, respectively.
Panchabhavi et al. 2004 reported that release of Chrysoperla carnea and other bio-control
agents at different intervals gave significant reduction of H. armigera and other sucking pests
Subramanian (2004) reported that pesticide (neemazal and azadirachtin based botanical
pesticide) had significant effect of antifeedant, deterrent, oviposition and ovicidal activity
against Spodoptera litura.
Deota and Upadhyay (2005) reported that azadirachtin, the active ingredient of A. indica
against S. litura showed toxicity and antifeedancy.
Hamd et al. (2005) reported that neem seed water extract was relatively safe to the aphid
predator Hippodamia variegate compared with neem Azal. The test materials varied in their
24
effects on the different developmental stages of the predator. In topical treatment with Neem
Azal, the corrected mortality was found, eggs 37.7, larvae 40.00, pupae 38.2 and adults
16.7% respectively, with neem seed water extract eggs 15.1, larvae 26.7, pupae 29.4 and
adults 10.0%. Sumicidin proved to be most detrimental to all the developmental stages of the
predator with % corrected mortality of eggs 86.8, larvae 100, pupae 73.5 and adults 100.
Feeding L2 larvae and adults of the predator on aphids treated with sumicidine resulted in
40% mortality in both stages whereas, neem seed water extract resulted in the lowest
corrected mortality of 25% for larvae and 17% for adults. The longevity of the adults fed on
aphids treated with neem seed water extract and neemazal was maximum (62.3 and 58 days)
and minimum (2 days) after feeding on aphids treated with sumicidine.
Regupathy et al. (2005) tested the preference of pests Empoasca kerri (groundnut), Amrasca
devastans [A. biguttula bigutulla], Aphis gossypii, Spodoptera litura, Aphis flava [A.
gossypii], Earias vittella, Helicoverpa armigera (cotton) and Cnaphalocrocis medinalis
(rice) towards trap crop/trap variety which was enhanced substantially by the application of
neem (Azadirachta indica) on trap crop/variety. Coccinellid species such as Menochilus
sexmaculatus [Cheilomenes sexmaculata], Coccinella transversalis and Alesia discolor
[Micraspis discolor], and the spider species such as Oxyopes sp., Argiope sp., Araneus sp.,
Neoscona sp. and Plexippus sp. showed their movement to the trap crops by the application
of neem on the main crops. The population and the occurrence ratio of coccinellid and
spiders on the trap crops were increased due to repellent action. Push-pull strategy having
conjunctive use of three components such as trap crops, viz. bhendi and red gram with
cotton, cowpea and soyabean with groundnut and trap variety (pest susceptible) with rice,
restricted application of neem with cotton, groundnut and rice leaving trap crops and
restricted application of nuclear polyhedrosis virus/Trichogramma chilonis/Bt on trap crops
was highly effective in reduction of the incidence of pests. An increase has been noted in the
%age recovery of Bacillus thuringiensis var. kurstaki-infected larvae from the treated plots,
and the %age parasitization by T. chilonis.
Aggarwal and Brar (2006) compared the contact feeding toxicity of NeemAzal with three
synthetic insecticides to whitefly parasitoid Encarcia sofia and the predator C. carnea.
NeemAzal at lower dose (200 mgL -1
) did not reduce the emergence of E. sofia adults from
whitefly nymphs but a strong reduction in emergence at higher doses (800 mgL -1
) was
observed. It did not cause contact toxicity to adults of E. sofia but the feeding mortality
25
activity was realized at high concentrations. All the three tested synthetic insecticides
induced a high toxicity both by contact and ingestion methods. Three neem preparations,
Neem azal, Nimbecidine and Godrej did not cause any adverse effects on the egg hatchability
and the mortality of the first instar larvae of C. carnea. However, a higher dosage of 800 mg
L -1
resulted in increased mortality of first and second instar larvae of C. carnea compared
with untreated control. Triazophos was extremely toxic and caused a very high mortality
(85.00, 89.00 and 81.50%) of first, second and third larval instars of the predator.
Isman 2006 reported that neem tree, Azadirachta indica A. Juss, belonging to family
Meliaceae, is an important source of 99 biologically active compounds, including
azadirachtin, nimbin, nimbidin and nimbolides and most of these products have antifeedant,
ovicidal, larvicidal, oviposition deterrent, growth regulating and repellent activities against
the insects.
Rajaram et al. 2006(b) conducted field trials in Tamil Nadu, India during Rabi 2002-03 and
2003-04 to see the effects of inorganic and organic amendments on the incidence of
leafhoppers (Amrasca biguttula) on cotton M.C.U.10. They noted that treatment with neem
cake basal application, resulted in the lowest leafhopper population of 0.62 and 1.27/leaf at
45 and 60 days after sowing (DAS), compared to 1.29 and 2.22 under the basal treatment N:
P: K at 40:20:0 kg ha -1
, respectively. Basal application of EFYM gave highest mean seed
cotton yield of 518 kg ha -1
.
Jat et al. (2006) In Haryana, India, studied the efficacy of neem seed kernel extract (at 3%,
5% and 7%) and neem oil (at 1%, 2% or 3%) against jassids (Amrasca biguttula) and
whitefly (Bemisia tabaci) on cotton (Gossypium hirsutum cv. H-1098). Pest population was
recorded at 0, 3 and 7 days after treatment (DAT). NSKE was least effective against Jassid
than Neem oil. The Jassid population decreased by 33.3% with 3% NSKE and increased by
up to 8.7% with 5% NSKE did not vary at 7% NSKE. The jassid population was decreased
by 20.4%, 34.4% and 42.5% with the application of 1%, 2% and 3% neem oil, respectively.
The neem treatments were equally effective against whitefly at 7 DAT; the whitefly
population at 3 DAT and 7 DAT was reduced by more than 50% and 60% respectively.
26
MATERIALS AND METHODS
Field and laboratory studies were conducted to evaluate effect of neem derivatives based
integrated cotton pest management. The details of procedure are presented in the respective
results and discussions chapter while common procedures are presented here.
3.1. Location of experiments
The experiments were conducted at Government Mandi Garden, Bhakkar (Latitude 31° 38
03.56 N, 71° 04 26.01 E and elev. 56 ft) during the year, 2005-06, the characteristic of the
soil and area are given in the tables below.
Table 3.1.1: Soil Characteristics
OM 0.62 %
3.2. Sowing of cotton.
Crop was sown at recommended time. Certified and delinted seed of cotton var. CIM-499
was obtained from Punjab Seed Corporation and was sown at Govt. Mandi Garden Bhakkar
Agriculture Department. Two consecutive crops were sown on 5 th
May 2005 and 2006. Crop
was sown in plots measuring 6m x 20 m with an area of 120 m 2 . Soil was prepared with
chisel plough to break the plough pan followed by two ploughing with tractor cultivator. The
land was leveled with leveler. The experiment was laid out in randomized complete block
design (RCBD) with 9 treatments and a control. Each treatment was replicated 3 times. Crop
was sown manually with hand drill keeping plant to plant and row to row distance of 25 cm
and 90 cm, respectively. Seed rate of 25 kg ha -1
was used.Fertilizer in the form of urea, DAP
and SOP was applied @ 398 (N), 143 (P2O5) and 124 (K2O) kg ha -1
. All phosphorus and
potash fertilizers were applied at the time of seed bed preparation while nitrogen was applied
in three split doses i.e. 1 st 35 days after sowing with first irrigation, 2
nd 60 DAS and 3
rd 90
DAS. Thinning was done 32 days after sowing to maintain plant to plant distance of 25 cm.
27
A distance of 200 m was kept between treatments of neem oil 1% + bio-control agent (N1 +
B), neem oil 2% +bio-control agent (N2 + B), neem seed water extract 2%+ bio-control agent
(W2 +B)and neem seed water extract 4%+ bio-control agent (W4 + B) to minimize
movement of adult of Trichogramma chilonis and Chrysoperla carnea between treatment
plots.
Climatic condition Arid
Mean rainfall from May to September: 36 mm
Minimum and Maximum Temperature Max : 30.15° C
Min : 15.52° C
Light Intensity 16 Hours
3.3. Preparation of neem derivatives i) Neem oil: Previous seasondried neem seeds, obtained from the local market
of District Bhakkar (Pakistan), were cleaned, crushed and oil was extracted
with local oil expeller. Oil was filtered through a batiste cloth. Detergent
powder (Surf Excel) @ 10 g L -1
of neem oil was also mixed as surfactant.
Desired solutions of 1% and 2% concentration were prepared by adding 10
and 20 mL of oil to one liter water respectively.
ii) Neem seed water extract (NSWE): Dried neem seeds weighing to 1 kg were
ground into powder manually mixed with ten grams detergent powder (Surf
Excel) was tied in a loose cotton cloth and dipped in a 5 liters hot water
(80 0 C) in pot and kept for 16 hours and then squeezed the cloth bag in the said
water. In this way stock solution of 20 % w/v was obtained. A diluted solution
of 2 and 4 % was prepared by using the formula C1V1=C2V2. The required
amount was prepared at the time of application.
3.4. Arrangement of bio-control agents
28
Bio-control agents (Chrysoperla carnea and Trichogramma chilonis) used in the field
experiments were collected from the rearing laboratories of Fecto Sugar Mill, Darya Khan
and Layyah Sugar Mill, Layyah (Pakistan). Eggs of both bio-control agents were transported
at 0° C in a temperature controlled container to avoid hatching before installation in the field.
3.5. Insecticides used
Insecticide viz. Thiamethoxim (Actara 24WG), Imidacloprid 25%WP, Fenpropathrin 20EC,
Profenophos+Cypermethrin (Polytrin-C 440EC) and Emamectin Benzoate (proclaim 19 EC)
were purchased from local pesticide dealers of the respective pesticide company.
3.6. Spray equipment
Knapsack sprayers (PB-20) and PP trigger sprayer (barber sprayer) were used for spraying
pesticides on cotton as per treatments.
3.7. Laboratory condition
Experiment was conducted under laboratory conditions of 30 °C ± 2, 60 ± 5% RH and 16:8
light: dark regimeat the premises of the office of District Officer Agri. Bhakkar.
3.8. Arrangement of Helicoverpa eggs
Helicoverpa eggs were collected from the laboratory of Ratta Kulachi Research station D.I.
Khan (Pakistan) to be used in laboratory experiment.
3.9. Rearing of Chrysoperla carnea
Artificial diet containing (20 g yeast + 9.89 g sugar + 5 mL water + 10 % honey) was
prepared and provided to the adult C. carnea in transparent plastic cage on daily basis. Eggs
of C. carnea were removed and collected from black paper card sheet fixed at the top of cage
with razor blade and placed for hatching in a plastic Petri dish. Upon hatching out, larvae
were transferred with fine tip camel hair brush to another plastic Petri dish (10 cm diameter +
2.5 cm height) for further use in the experimentation.
29
CHAPTER-4
Study-1. Effect of neem derivatives alone, in combination with bio-control agents and
synthetic insecticides on insect pest complex of cotton and its yield.
4.1. Abstract
Variety of insect/pests attacking on cotton crop, are mostly controlled by synthetic
insecticides due to their knockdown effects which cause other complications i.e.
environmental pollution, health hazardous for men and animals etc. To minimize these ill
effects of insecticides, plants derivatives and bio-control agents are good option of these
insect pests. In present study, conducted at Government Mandi Garden, Bhakkar under field
condition was to see effect of neem products in IPM approach on insects/pests of cotton and
their predators and parasitoids.Neem derivatives at all concentrations alone or in
combinations with bio-control agents have significantly reduced the population of sucking
and chewing insects.Overall effect of sprays showed that neem oil 2% + bio-control agents
(N2+B) was more effective than rest of the test treatments inmaximum % population
reduction of sucking and minimum % infestation of chewing insects168 hours after each
spray except insecticide.Similarly, more yield of cotton was obtained in the treatment of N2
+B after insecticide. These results indicate that neem derivatives can be incorporated with
IPM programs of cotton.
4.2. Introduction
Pakistan economy is agro based and cotton is the most earning crop. Its low production due
to pest infestation, affect overall trade. Pests like Bemisia tabaci Genn., Emrosca devastans
Dist., Thrips tabaci Lind., Dysdercus koenigii Fab., Tetranychus urticae, Earias vittella F.,
Earias insulana Boisd., Pectinophora gossypiella Saund., Helicoverpa armigera Hubner.,
and Spodoptera litura F. are among the destructive in cotton. Synthetic chemicals fail to
control of outbreak. There is dire need to develop eco and environmental friendly measures
to combat this menace. Integrated pest management (IPM) is long lasting and eco-friendly
measures (Sundaramurthy et al., 1998).
30
Plant derivatives and biological control (predators and parasitoids) can be used as an
alternative approach to synthetic chemicals which are cost effective, easily available and are
of the compatible integrated crop management approach for pest management (Copping and
Menn, 2000).
Azadirachtin and numerous other compounds derived primarily from neem have insecticidal,
antifeedant and toxicological properties for insects control (Schmutterer, 1990). In Pakistan,
neem is widely grown in Sindh and Punjab. Neem based insecticides are marketed as brand
name of “Nimbokill” for crop insect and “Nimboli” for household pests in Pakistan.
Effective components of neem are in its seed. To extract these compounds as oil, seeds are
dried and shelled. The seed kernels are either passed to get oil or their powder is dissolved in
solvent like water, ether, Acetone, petroleum etc.
Biological control of insect pest of cotton can yield promising results. Several predators and
egg parasitoid, Trichogramma chilonis can play an effective role in the management of insect
pests on cotton crop.
Neem can also fit effectively into an IPM system with conservation of beneficial bees,
predators, parasitoids, mammals and environment (Ahmad and Grainage, 1986; Tang et al.,
2002). Being selective, with no or less negative impact on the ecosystem and works in
association with biological control organisms could be an interesting option for IPM (Starks
and Rangus, 1994; Immaraju, 1998; Tang et al., 2002).
Keeping in view the importance of cotton crop in the economy of Pakistan and pest status of
sucking and chewing insects of cotton, the study was conducted to investigate
antifeedant/deterrent and residual effect of neem derivatives alone and in combination with
bio-control agents on the sucking and chewing insects (bollworms) of cotton.
4.3. Experimental procedure
General procedure regarding sowing of crop, layout and extraction of neem oil and extracts is
given in material and method, Chapter-3. Specific methods are given below.
4.3.1. Treatments applied
31
N2+B Neem oil 2%+ Bio-control agents (Chrysoperla eggs @12500 ha -
1 +Trichogramma eggs @ 150000 ha
-1 )
N1+B Neem oil 1%+Bio-control agents (Chrysoperla eggs @12500 ha -1
+Trichogramma eggs @ 150000 ha -1
)
W4+B Neem seed water extract 4 % + Bio-control agents (Chrysoperla eggs
@12500 ha -1
+Trichogramma eggs @ 150000 ha -1)
W2+B Neem seed water extract 2 %+ Bio-control agents (Chrysoperla eggs
@12500 ha -1
) (1 st spray)
) (2 nd
) (3 rd
) (4 th
) (5 th
4.3.2. Spray schedule
The crop was sprayed 5 times with pesticides (sequential sprays). First spray was carried out
on 45 DAS and repeated at an interval of 15 days of first spray. Three Chrysoperla cards
having150 eggs were installed/hanged using the hole on the edge of the card into foliage in
the middle of plants in such a manner to protect it from direct sunlightwhile two trichocard
having 1800 eggs were stapled at the lower side of the upper third leaves soon after spray of
neem derivatives in the treatment plots of N2 + B, N1 + B, W4 + B and W2+ B. Different
groups of insecticides were used in five sprays to control sucking and chewing insects and
also to minimize the selection pressure of resistance development in the insects. Polythine
sheet was placed between plots during spray to avoid chemical drift.
Spray Repeat interval
4.3.3. Observation recorded
Population of sucking pests was recorded at weekly interval in the morning by counting
[Jassid (nymphs and adults) and whitefly (nymphs and adults)] through pest scouting
techniques (Maryo method). From each treatment replication, 20 cotton plants were selected
32
randomly. Leaves from each plant comprising upper, middle lower part of canopy were
observed for pest population. Each pest was counted carefully on both sides of the leaves and
its average was computed. Data on thrips population were recorded from the same leaves that
were used for jassids and whiteflies but thrips were counted on an area of 6.25 cm 2 from the
underside of cotton leaves.
Population dynamics of thrips, whiteflies and jassids was recorded 24 hours before the
application of treatment followed 24, 168 and 336hours after each spray. Percent population
reduction was computed by using Abbotts formula (Fleming and Retnakaran, 1985.).
% population Density reduction = [1-(popT/prpT x prpc/popc) x100
popT = The Population of sucking pests after insecticide application.
prpT = Sucking pests population in the treated plot before the application of
insecticides.
prpc = The population of sucking pests in the un-treated plots before spray.
popc = The population of sucking pests in check/ un-treated plots after application
of insecticide.
Population of sucking insects 24 hours before spray and of the control were used to compute
% population reduction of sucking insects in Abbotts formula.
The data for Earias insulana and Helicoverpa armigera infestation were recorded in 10
randomly selected plants from each treatment replication by counting total immature fruiting
parts (buds and flowers), mature fruiting parts (bolls) and damaged immature fruiting and
mature fruiting parts. The data were recorded on 168 and 360hours after each pesticide
application. The recorded data were converted into percent damage with the following
formula.
% damage fruiting bodies = Damaged fruiting bodies/total fruiting bodies x 100.
For Pectinophora gossypiella infestation, 20 bolls collected randomly from each treatment
replication, were brought to the laboratory with a total of 60 bolls from each treatment. Bolls
were dissected and infestation caused by pink bollworm was recorded. The bolls were
collected on 15 th
of August, 14 th
September and 15 th
October at monthly basis for both crops.
The recorded data were converted into percent damage. To know the effect on the yield of
33
seed cotton, the picking was started when 50 % bolls were open/ready for picking and was
continued up to end of crop. Yield of each treatment was converte

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NEEM DERIVATIVES BASED INTEGRATED PEST MANAGEMENT …