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International Symposium
on Current Trends in Plant Protection
Belgrade, 25. – 28.09.2012.
THE CURRENT STATUS OF THE TOBACCO
WHITEFLY - BEMISIA TABACI (GENNADIUS)
(HEMIPTERA: ALEYRODIDAE) IN MONTENEGRO
Snježana Hrnčić1, Sanja Radonjić1, Tatjana Perović1, Katja Žanić2, Marisa Škaljac2
1University of Montenegro, Biotechnical Faculty, Podgorica, Montenegro
2Institute for Adriatic Crops and Karst
Reclamation, Split, Croatia
INTRODUCTION
• Bemisia tabaci (Gennadius) was described in Greece over 100 years ago and since than has become one of the most important pests in subtropical and tropical agriculture.
• It is a pest in the greenhouses and open fields, which adapts easily to new host plants and geographical regions.
• In recent years, international transport of plant material have contributed to its geographical spread.
• It is considered one of the world’s top 100 invasive species
• B. tabaci is extremely polyphagous, feeding on more than 700 host plant species within 86 botanical families.
• It causes damage to a numerous vegetable crops such as tomato, tobacco, eggplant, pepper, beans, cucumber, melon, and ornamental plants, especially Euphorbia pulcherrima.
• Adults and larvae feed by sucking the phloem sap and can cause
damage directly and indirectly by excretion
of honeydew onto the leaf surface
• B. tabaci transmits several economically devastating viruses.
• In general, it vectors 111 virus species in several genera:
Begomovirus, Crinivirus and Ipomovirus
• Important aspect of B. tabaci is a high genetic variability that exists among its populations.
• B. tabaci is morphologically indistinguishable species complex which differs biologically and genetically.
The world’s two most widespread and damaging
members of the B. tabaci species complex are:
the Middle East-Asia Minor 1 (MEAM1, known as a B
biotype)
Mediterranean (MED, known as a Q biotype.
They are known for their wide host range, high
fecundity, insecticide resistance and ability to transmit
plant viruses and induce plant disorders
B. tabaci is spread in most of Mediterranean countries.
Among countries of the region, B. tabaci was found in
Croatia and Bosnia and Herzegovina in greenhouses,
as well as in the open field
MATERIAL AND METHODS
• In the period from 2008 to 2011 several times during summer months (June – September) lower side of leaves of ornamental and vegetable plants, in the area of Podgorica and at Montenegrin seaside were visually examined for the presence of pre-adult stages of B. tabaci.
In 2008 one greenhouse with ornamental plants and
one with vegetable plants (cucumber, tomato and
pepper) in the area of Podgorica were examined.
In 2009:
ornamental plants in two greenhouses in the area of Podgorica,
two greenhouses in the Bar area,
one greenhouse in the area of Ulcinj and
two in the area of Tivat, were examined.
At the same time, examinations of vegetable plants in:
two greenhouses (tomato) in Zeta area (Podgorica),
two greenhouses in the area of Ulcinj (tomato and cucumber) and
one greenhouse in Tivat area (tomato).
In 2010 and 2011 besides the greenhouses examined in 2009:
one more greenhouse with ornamental plants in Ulcinj area,
one greenhouse with vegetable plants (tomato, cucumber) in Bar area were included in examination,
one tomato and melon crop in the open field in Ulcinj area, but only in 2011.
The leaves on which presence of larvae, pupae
and exuvium were observed were examined under
stereomicroscope in the laboratory.
EPPO Diagnostic protocols for regulated pests
were used in morphological determination of B.
tabaci.
Based on morphological properties of certain development stadiums, particularly pupa and exuvium, the presence of B. tabaci was confirmed.
RESULTS
Adults are small, with yellow colored body, not more than 1 mm long. The males are slightly smaller than the females.
Eggs are laid in piles or in circular groups, vertically on
lower side of leaves.
They are anchored to the leaves by a short pedicel. When
first laid, eggs are light yellow and become brown at the end
of embryonic development.
Larval body is flat,
oval.
It is 0.3 mm long in
first stage larvae and
0.6 mm in fourth stage
larvae.
On third and fourth
stage larvae red
eyes are visible
Pupae are yellow, convex, about 0.7 mm long. Body
margin is irregularly shaped depending on leaf structure
of the feeding plant.
The presence of B. tabaci in Montenegro was firstly observed in the middle of May in 2008 on hibiscus in a residential building in Podgorica.
Adults, larvae, pupae and exuvium were observed on the leaves which indicated that the species completed the development cycle on the hibiscus.
Distribution of B. tabaci in Montenegro Origin of B. tabaci is
not familiar, however concerning that most of ornamental plants are imported from Italy, it was probably introduced by this way.
In the following years of monitoring, the presence of tobacco whitefly was confirmed in the area of Podgorica and Montenegrin seaside.
Year Locations and host plant
2008. Podgorica greenhouse: Hibiscus sp. (Malvaceae), Abutilon sp. (Malvaceae),
Lippia citriodora (Verbenaceae), Lantana camara (Verbenaceae), Tumbergia
sp. (Acanthaceae), Sonchus oleraceus (Asteraceae)
Podgorica open field: Lantana camara and Verbena sp.
2009. Podgorica greenhouse: Abutilon sp., Lantana camara, Lippia citriodora,
Sonchus oleraceus
Tivat – Radanovići greenhouse: Abutilon sp.
Bar greenhouse: Euphorbia pulcherrima (Euphorbiaceae)
2010. Podgorica greenhouse: Abutilon sp., Lippia citriodora
Bar greenhouse: Euphorbia pulcherrima
2011. Podgorica greenhouse: Abutilon sp., Lippia citriodora, Sonchus oleraceus
Bar 1 greenhouse: Dipladenia sanderi (Apocynaceae)
Bar 2 grennhouse: Dipladenia sanderi, Lantana camara, Euphorbia
pulcherrima, Gerbera jamesonii (Asteraceae)
Ulcinj greenhouse: Dipladenia sanderi
Ulcinj open field: Cucumis melo (Cucurbitaceae)
Recorded host plants and finding locations of B.tabaci in Montenegro
The fact that in September 2008 B. tabaci was found on Lantana camara and Verbena sp. on a balcony in Podgorica and that on the same hosts and locality in the following year it was not present suggests that this species does not easily adapt to climatic conditions of Podgorica.
This indicates that B. tabaci cannot survive in outdoor conditions in Podgorica
Dipladenia sanderi
was recorded as
favourable host plant
Although the subject of this paper was not genetic variability of B. tabaci, in the research conducted by Škaljac et al. (2010) it was found that B. tabaci collected from Hibiscus sp. in 2008 in Podgorica belonged to MEAM1 genetic group.
In 2011, both MEAM1 and MED B. tabaci species were found in Montenegro.
MEAM1 was found again in Podgorica and infested Sonchus oleraceus, while MED group infested Dipladenia sanderi in Bar and Ulcinj.
MED group of B. tabaci infested melon in the open field in 2011 near Ulcinj.
These results suggest that B. tabaci was introduced to Montenegro on several occasions.
ACKNOWLEDGEMENTS
The autors thank Milorad Raičević from Biotechnical faculty in Podgorica for his valuable help.
THANKS FOR YOUR
ATTENTION
Sanja Tatjana i Katja Marisa