Studies were conducted to evaluate some new chemistry insecticide molecules as foliar application for their bioefficacy against major sucking pests and toxicity against predators of Bt transgenic

The laboratory experiment was conducted during 2017-2018 to study the different biological attributes of Trichogramma chilonis Ishii as influenced by host eggs of different ages. Significantly maximum percent egg parasitization was noticed on eggs of Helicoverpa armigera (Hübner) with 62.39 percent which was at par with the Corcyra cephalonica (Stainton) eggs (60.36 percent). This was followed by Earias vittella Fabricius 46.31 percent. Less parasitized eggs were recorded in Leucinodes orbonalis Guenée (10.35 percent). Age of host eggs significantly affected the parasitization by T. chilonis. The maximum parasitization (58.87 percent) was noticed in fresh eggs i.e. 24 hrs old followed by 48 hrs (44.91 percent) while 72 hrs old eggs were less preferred by T. chilonis and could parasitize only 30.56 percent. Development period for parasitoid ranged between 8.66 to 9.44 days on different host eggs. The highest adult parasitoid longevity (7.22 days) was observed from the parasitized eggs of H. armigera which was at par with C. cephalonica (7.10 days), E. vittella (6.88 days) and L. orbonalis (6.88 days). However, the different lepidopteran eggs as well as age of host eggs did not show significant differences pertaining to percent adult parasitoid emergence. Fresh host eggs of 24 hrs could produce more female progeny of T. chilonis (54.30 percent) compared to 72 hrs old eggs (42.65 percent). The sex ratio (male: female) of emerging parasitoid progeny was observed highest on 24 hrs old eggs (1:1.55) followed by 48 hrs old eggs (1:1.23) while lowest sex ratio was observed on the eggs of 72 hrs old age (1:0.95). The maximum per day fecundity of T. chilonis was noticed on the 24 hrs old eggs (6.75) followed by 48 hrs old eggs (4.80). The lowest fecundity (2.05) of T. chilonis was observed on the 72 hrs old eggs, whereas the highest male-female ratio and fecundity was noticed on eggs of E.vittella among different hosts.

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<p>Influence of rearing temperature on biological parameters of <em>Trichogramma chilonis</em> (Ishii) was studied under laboratory conditions during 2017-18. Maximum per cent parasitization and adult emergence of 74.2% and 78.91%, respectively was observed at 25+1°C followed by 71.8% and 65.21 % at 30±1°C. However, the temperature of 40+1°C was found detrimental to<em> T. chilonis</em> recording only 20.2% parasitization, the progeny of which has failed to complete the development and the adults could not emerge out. The developmental period was maximum (8 days) at 25+1°C. Also, maximum male and female longevity (5 and 12 Days, respectively) and maximum mean per day fecundity of 17 eggs per female/day were recorded at 25+1°C. The progeny was found to be male dominated with a female-male ratio of <em>T. chilonis</em> to be 0.69, 0.74 and 0.96 at 25, 30 and 35°C, respectively.</p>

Eight insecticidal treatments (including insect growth regulators) were evaluated against aphids (Aphis gossypii Glover) and thrips (Thrips tabaci Lindeman) in Bt cotton. The results revealed that buprofezin 25%SC proved effective in minimizing the A. gossypii. However, it was found at par with pyriproxyfen 10% EC. Buprofezin 25%SC also led to minimum number of T. tabaci and was found at par with pyriproxyfen 10%EC, buprofezin 25%SC+ NSKE 5%, pyriproxyfen 10%EC+ NSKE 5% and NSKE 5%. No deleterious effect of these were observed on the natural enemies. Maximum seed cotton yield was obtained with buprofezin 25%SC and it proved to be the economically viable with ICBR of 1: 6.6.