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STUDIES ON THE EFFECT AND EFFICACY OF
BIOLOGICAL SEED COATING AGAINST
MACROPHOMINA PHASEOLINA IN MAIZE J. SANDHYA RANI, P. SUJATHA*, K. JHANSI RANI, S. TRIVENI and M.V. NAGESH KUMAR
Department of Seed Science and Technology, Seed Research and Technology Centre,
Professor Jayashankar Telangana State Agricultural Uiversity, Rajendranagar, Hyderabad 500 030
*[email protected], +91-9491128885
Biological seed coating is an ecological approach using selected fungal
antagonists against the soil and seed-borne pathogens and it has a potential to
provide an alternative to chemical control. The present experiment is planned to
study the compatibility of bioagents with seed protectants, its effectiveness
against test pathogen under invitro and under invivo conditions after of three
months of seed coating
Material and Methods
An experiment was conducted at the Department of Seed Science and
Technology, PJTSAU during Kharif 2017 and Rabi 2017-18 by treating maize
seed of DHM 117. It was laid out in Completely Randomized Design (CRD)
with 4 treatments, 3 replications and kept for storage in polythene bags.
Introduction
Plate 4: SEMs of seed and root surfaces showing the presence of T. viride (hyphae and
conidia at x 1000) and B. Subtilis (bacterial cells at x250)
T1 Chemicals (Thiamethoxam @ 3 g kg-1 seed + Metalaxyl @ 2 g kg-1 seed) +
Bio-friendly Polymer (6g kg-1)
T2 T1+ Biocontrol agents (Trichoderma viride @ 5 g kg-1 ; Pseudomonas
fluorescens @ 10 g kg-1 seed; Bacillus subtilis @ 10 g kg-1 seed) +Bio-
friendly Polymer (6g kg-1)
T3 Biocontrol agents (Trichoderma viride @ 5 g kg-1 ; Pseudomonas
fluorescens @ 10 g kg-1 seed; Bacillus subtilis @ 10 g kg-1 seed) +Bio-
friendly Polymer (6g kg-1)
T4 Untreated control
Compatibility studies were conducted through poisoned food technique for
fungal biocontrol agents and though inhibition zone technique for bacterial
biocontrol agents by using Potato Dextrose Agar medium (T. viride), King’s B
medium (P. fluorescens) or Pikovskaya medium (B. megaterium). In vitro
efficacy of biocontrol agents against the test pathogen (Macrophomina
phaseolina) was studied through dual culture technique. Standard germination
test was conducted in four replications of 100 seeds each (ISTA, 2007).
Results and Discussion
Compatibility of T. viride with seed coating materials
RESULT: Trichoderma viride, Pseudomonas fluorescens and Bacillus subtilis
showed compatibility with the insecticide thiamethoxam and biofriendly
polymer. With fungicides, bioagents showed some compatibility with metalaxy
and incompatibility with sixer.
Plate1. Radial growth of T. viride in the compatibility studies through poisoned
food technique
Efficacy of bioagents against test pathogens Macrophomina phaseolina
RESULT: All bioagents showed inhibition of Macrophomina phaseolina (major
causative organism of Post Flowering Stalk Rot in maize), under invitro conditions
SCANNING ELECTRON MICROGRAPHS
RESULT: Scanning Electron Micrographs revealed the presence of biocontrol agents
on seed and root surfaces of maize even after four months of biological coating
Maize seed coated with biocontrol agents, bio friendly polymer, insecticides and
compatible fungicides retain its viability even up to 7 months of treatment and with
less incidence of storage pests and diseases thereby improving the field performance
of the crop.
Conclusion
RESULT: Biological coating with chemical protectants recorded significantly more
seed germination & longevity under laboratory conditions and final plant stand under
field conditions compared to biological seed coating without chemical protectants
References International Seed Testing Association, 2007. International Rules for Seed Testing.
Bassersdorf, Switzerland. ISTA News Bulletin, 133.
Jagadeesh V, Sujatha P, Keshavulu K & Triveni S. 2016. Studies on Biological seed
coating in pigeonpea. M. Sc. Thesis. PJTSAU.
O’Callaghan M. 2016. Microbial inoculation of seed for improved crop performance:
issues and opportunities. Appl Microbiol Biotechnol, 100. 5729.
Acknowledgements Authors acknowledge the support of Dr. K. Raghavendra, Centor India Agri Pvt Ltd,
Hyderabad for supplying biofriendly polymer.
Plate 2. Zones of inhibition of P. fluorescens in the compatibility studies
through inhibition zone technique
Plate3. In vitro efficacy of Trichoderma viride and Bacillus subtilis
Effect on seed germination (%) after 7 months of storage and field performance
58687888
Chemicals +
Polymer
Chemicals +
BCA + Polymer
BCA + BF
Polymer
Untreated
Control
80 77
62
80
Mai
ze S
eed
ger
min
atio
n (
%)
- 7
MA
T
Seed Coating Materials
68
68.5
69
69.5
70
70.5
71
chemicals+Polymer Chemical+BCA+
Polymer
BCA+ Polymer Untreated control
71 71
69 69
Fin
al
pla
nt
sta
nd
(N
o.)
Seed Coating Material
Figure 1: Effect of Biological seed coating on seed germination (%)
Figure 2: Effect of biological seed coating on field performance