An experiment was undertaken to know the effect of different honey bee species (Apis cerana, A. florea, A. mellifera, A. dorsata and Trigona iridipennis) and protein sources (pollen, soya flour, red gram flour and horse gram flour) on the economic traits of silkworm Bombyx mori L. by using of different concentrations (1%, 2%, 3%, 4%, 5% and 6%). Among the different treatments, T. iridipennis honey at 5% showed better performance on the silkworm growth and its economic parameters viz., larval weight (3.44g), cocoon weight (1.59g), shell weight (0.372g) and shell ratio (23.46%) followed by soya flour and red gram flour. The supplementation of 5% soya flour showed highest silk filament length (1321.15m) which was found to be on par with T. iridipennis honey (1312.15m).

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Combining ability in mulberry was assessed by using Line x Tester mating design. In the present study, five lines viz., MI-0543, MI-0615, MI-0651, MI-0685, MI-0718 and three testers' viz., V1, G4, MI-0663 were crossed to obtain fifteen F1 progenies. Growth and survivability traits were evaluated for the F1 crosses through Analysis of variance (ANOVA), General combining ability (GCA) and Specific combining ability (SCA) for the parameters such as germination per cent, survivability per cent, plant height, number of leaves per branch, internodal distance and leaf moisture content. Among the eight parental genotypes MI-0543 (female) and V1 (male) were the best combiners and MI-0685 x V1 was the best cross for growth and survivability traits. Hence, both non-additive and additive gene actions are important for the mulberry improvement.

Chitosan is biopolymer of glucosamine residues, nontoxic, biodegradable and friendly to environment and it also helps to enhance crop production due to their bioactivities. The present experiment was conducted to assess the efficacy of chitosan on the growth and yield related attributes of mulberry, Morus sp. with various concentrations such as 25, 50, 75, 100 and 125 ppm. The chitosan was sprayed thrice on 15, 30 and 45 days after pruning (DAP) on the foliage of three different mulberry varieties namely V1, MR2 and G4. The result revealed that, irrespective of varieties, the foliar application of chitosan at 75 ppm significantly increased the biometric as well as yield related attributes of mulberry over other concentrations. Among the three varieties, V1 showed more response to chitosan application than G4 and MR2. At 75 ppm, chitosan showed marked effect on VI variety of mulberry and significantly increased shoot length (170.67 cm), number of shoots per plant (9.03), number of leaves per shoot (29.48), leaf area (220.26 cm2) and leaf area index (2.72) were observed when compared with control. The application of chitosan at 75 ppm significantly enhanced the yield traits namely weight of 100 leaves (448.10 g), leaf shoot ratio (1.45) and leaf yield (14.01 MT/ha/harvest) in V1.

An Artificial Diet composed of castor leaf powder (11.5 g), parched soybean powder (1.0 g), sucrose (1.0 g), agar-agar (1.5 g), inhibitor solution (5 ml) and water (20 ml) was evaluated against eri silkworm larvae. Castor fed eri silkworms were maintained as control for comparison. Larval weight was significantly maximum in eri silkworms fed with artificial diet upto first instar which was followed by feeding of eri silkworms on artificial diet upto second instar + castor leaves from upto fifth instar and feeding of eri silkworm on artificial diet upto third instar + castor during remaining instars. Whereas, the larval mortality was minimum in eri silkworms reared on artificial diet upto first instar followed by artificial diet upto second and third instars + castor during remaining instars, whereas, they were higher in eri silkworms fed on artificial diet upto fourth and fifth instars + castor during remaining instars.