MSc

Brinjal (Solanum melongena L.) is a plant of considerable conomic
importance in many tropical and sub tropical parts of the world. It is a popular
vegetable grown as poor man’s crop in India. It is a native of India and is grown
throughout the country. The brinjal crop is usually infested by a number of pests
right from nursery stage till harvest. Among the insect pests, the most important
and destructive ones are shoot and fruit borer, Leucinodes orbonalis; epilachna
beetle, Epilachna vigintioctopunctata; leaf roller, Antoba olivacea and hairy
caterpillar, Selepa docilis. For the management of these pests, the conventional
pest management practices often provide unsatisfactory results. Further, the use
of chemical pesticide results in insecticide resistance, pest resurgence, destruction
of natural enemies and pesticide residue in the harvested produce and related
environment and health hazards. Hence, there is an impetus for research and
development of eco-friendly and biorational alternative for the sustainable
management of major pests of brinjal.
A survey was conducted in the three agro climatic regions of Kasargod
district viz., low, mid and high land area. The survey revealed that per cent
incidence of pests like L. orbonalis, E. vigintioctopunctata and A. olivacea were
severe on brinjal in low, mid and high land area of Kasargod district. However,
severe infestation of S. docilis was noticed in low land, compared to mid and high
land area of Kasargod district.
Spinosad 45 SC was found to be effective in controlling the shoot and fruit
borer of brinjal during both summer and kharif season. Azadirachtin 1% was
found to be most effective in controlling E. vigintioctopunctata adults as well as
grubs. It was also found to be effective in reducing mean per cent of leaf
infestation during both summer and kharif season. The Bt formulation was found
to be highly effective for early instar larvae of A. olivacea. However, for older
instar caterpillars, malathion 50 EC was found to be effective during both summer
and kharif season. The azadirachtin 1% was found to be highly effective against
S. docilis as compared to other treatments during both summer and kharif season.
The spinosad 45 SC was safer to natural enemies like predatory coccinellids and
spiders in brinjal ecosystem.
The yield of brinjal plant was higher in spinosad 45 SC treated plots and a
higher return was obtained worth Rs. 2.52 and Rs. 2.67 during both summer and
kharif season respectively for every one rupee invested.
Effect and compatibility of spinosad 45 SC on entomopathogenic fungi
using poisoned food technique under in vitro condition revealed that spinosad 45
SC is not compatible with M. anisopliae and B. bassiana in terms of colony
development, sporulation and spore germination.
Residue of major and minor component of spinosad 45 SC were below the
maximum residue limit.