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Nutrition plays a pivotal role in sericulture. It improves the growth, development, health, feed consumption and conversion of silkworm thereby improving the commercial traits. Silkworm, Bombyx Mori L., is a monophagous insect that drives almost all required nutrients for its growth and development from mulberry leaf. Application of the required nutrient in the required amount to mulberry plant is, therefore, very essential for the successful silkworm growth and cocoon production. The present investigation was carried out at the department of sericulture, GKVK, UAS, Bangalore, India in 2007 with an objective to determine the effect of three bio-inoculants application to M 5 mulberry plant on silkworm (PM x CSR 2 ) growth, development and coocoon traits. The feeding experiment was laid-out in Completely Randomized Design (CRD)with eight treatments replicated three times. The result revealed that the larval growth variables and cocoon traits were significantly better when developing worms were fed on mulberry leaves raised by applying the recommended doses of nutrients. However, the recommended rate of chemical fertilizers application was found either the same or on par with 25 per cent reduced Nitrogen and Phospherous (NP) application when supplemented with bio-inoculants (Azotobactersp., Aspergillus awamori and Trichodermaharzianum). This indicate that 25 per cent reduction of NP application does not adversely affect larval growth and cocoon traits when supplemented with the above three microbes.

In storage, maize grains are severely destroyed by insects and other storage pests. One of the primary causes of grain loss in stored maize is the damage caused by maize weevil, Sitophilus zeamais. A study was conducted to evaluate selected locally available botanical powders and cooking oils for their effectiveness as grain protectants against maize weevils at JUCAVM in year 2011. The plant powders and cooking oils were compared with untreated control and Malathion super dust as standard check. The experiment was laid-out in Completely Randomized Design with 13 treatments each replicated thrice. Different dependent variables such as cumulative adult mortality, F 1 progeny emergency, grain damage were assessed. The results revealed that, among the botanical powders, there was an increased cumulative adult S. zeamais mortality, i.e. higher mortality, from powders of Chenopodium ambrosoides (70% with LT 50 of 6.50 days), Azadiricta indica leaf (70% with LT 50 of 6.00 days), A. indica bark (70% with LT 50 of 8.40 days) and Tagetus erecta (70% with LT 50 of 9.20 days) after 20 days of exposure periods. Apart from the untreated control, low mortality of S. zeamais adult was recorded from Allium sativum (50% with LT 50 of 18.01 days), C. citratus (55% with LT 50 of 18.30 days), Maesa lanceolata (55% with LT 50 of 16.20 days) and Echinops kebericho (55% with LT 50 of 14.50 days) after 20 days of exposure periods. Highest S. zeamais adult mortality of 95%, 100% and 100% was recorded from Brassica carinata oil, Gossypium hirsutum oil and the standard chemical Malathion, respectively with LT 50 of less than one day in all cases. Maximum number of progeny was emerged from untreated check from 25 th~4 0 th days of exposures with cumulative increase (2 to 14 adults). There was no F 1 progeny emergency from the three treatments (oils and Malathion) over the exposure periods reassuring the potency of the cooking oils against S. zeamais. As a result there was no perforated seed; no weight loss and maximum germination percentage of 94.60% were registered from the two cooking oils on par with the Malathion (95.50%). In conclusion, the two cooking oils were found to be the most potent bio-insecticides on par with standard check, Malathion and they can be used in integrated management of maize weevil, S. zeamais.