Abstract:In order to amalgamate the effects of nutrition and its efficiency on genetic traits expression in silkworm germplasm breeds by serial analysis on nutrigenetic traits and utilized as biomarker with an aim to identify nutritionally efficient silkworm germplasm breeds. In the present study, six bivoltine silkworm breeds were subjected for investigation on ingestion, digestion and utilization of dry food matter in single silkworm larva and its sharing on economically important stages larva, cocoon and shell weight in 5th stage. It was resolved that low consumption with high conversion efficiency of food ingested in silkworm breeds on nineteen nutrigenetic traits analyzed by standard gravimetric method with the aid of INDOSTAT software to understand the nutrigenomic divergence among the silkworm germplasm breeds against different seasons. Results indicated that higher conversion efficiency was observed in most of the new silkworm breeds for Efficiency of Conversion of Ingesta (ECI) to cocoon and shell than control (APS ) as leaf -cocoon and leaf-shell conversion 8 are the ultimate indices in nutrigenomic analysis. It also demonstrated that relatively smaller amount of Consumption Index (CI), respiration, Metabolic Rate (MR) with superior Relative Growth Rate (RGR) and in relation to quantum of food ingesta and digesta requisite per gram of cocoon and shell found less than the control. This concluded that nutrigenetic traits directly associated to the quantum of food ingesta and digesta gG of cocoon and shell and such nutrigenetic study pragmatically utilized as biomarkers in order to 1 advocate sturdily the following breeds viz., RBD , RBD (peanut type cocoon), RBO , RBO (oval type cocoon) 1 4 2 3 were chosen as highly nutritionally efficient bivoltine silkworm germplasm breeds.

A tropical climate prevails in most of the sericultural areas in India, where temperature increases during the summer lead to adverse effects on temperate bivoltine silkworm rearing and cause crop losses. Screening for thermotolerance in the silkworm, Bombyxmori L. (Lepidoptera: Bombycidae) is an essential prerequisite for the development of thermotolerant breeds/hybrids. In the current study, the aim was to identify potential bivoltine silkworm strains specific for tolerance to high temperature. The third day of fifth stage silkworm larvae of bivoltine strains were subjected to high temperature of 36 ± 1° C with RH of 50 ± 5 % for six hours (10:00–16:00) every day until spinning for three consecutive generations. Highly significant differences were found among all genetic traits of bivoltine silkworm strains in the treated groups. Three groups of silkworm resulted including susceptible, moderately tolerant, and tolerant by utilizing pupation rate or survival rate with thermal stress as the index for thermotolerance. Furthermore, based on the overall silkworm rearing performance of nine quantitative genetic traits such as larval weight, cocoon yield by number and weight, pupation, single cocoon and shell weight, shell ratio, filament length and denier, three bivoltine silkworm strains, BD2-S, SOF-BR and BO2 were developed as having the potential for thermotolerance. The data from the present study enhance knowledge for the development of thermo tolerant silkworm breeds/ hybrids and their effective commercial utilization in the sericulture industry.

The activity of sericulture is declining due the reduction of mulberry production area in sericulture practicing countries lead to adverse effects on silkworm rearing and cocoon production. Screening for nutrigenetic traits in silkworm, Bombyx mori L. (Lepidoptera: Bombycidae) is an essential prerequisite for better understanding and development of nutritionally efficient breeds/hybrids, which show less food consumption with higher efficiency conversion. The aim of this study was to identify nutritionally efficient polyvoltine silkworm strains using the germplasm breeds RMW2, RMW3, RMW4, RMG3, RMG1, RMG4, RMG5, RMG6 and APM1 as the control. The 1st day of 5th stage silkworm larvae of polyvoltine strains were subjected to standard gravimetric analysis until spinning for three consecutive generations covering 3 different seasons on 19 nutrigenetic traits. Highly significant (p ≤ 0.001) differences were found among all nutrigenetic traits of polyvoltine silkworm strains in the experimental groups. The nutritionally efficient polvoltine silkworm strains were resulted by utilizing nutrition consumption index and efficiency of conversion of ingesta/cocoon traits as the index. Higher nutritional efficiency conversions were found in the polyvoltine silkworm strains on efficiency of conversion of ingesta to cocoon and shell than control. Comparatively smaller consumption index, respiration, metabolic rate with superior relative growth rate, and quantum of food ingesta and digesta requisite per gram of cocoon and shell were found; the lowest amount was in new polyvoltine strains compared to the control. Furthermore, based on the overall nutrigenetic traits utilized as index or ‘biomarkers’, three polyvoltine silkworm strains (RMG4, RMW2, and RMW3) were identified as having the potential for nutrition efficiency conversion. The data from the present study advances our knowledge for the development of nutritionally efficient silkworm breeds/hybrids and their effective commercial utilization in the sericulture industry.

The activity of sericulture is declining due the reduction of mulberry production area in sericulture practicing countries lead to adverse effects on silkworm rearing and cocoon production. Screening for nutrigenetic traits in silkworm, Bombyx mori L. (Lepidoptera: Bombycidae) is an essential prerequisite for better understanding and development of nutritionally efficient breeds/hybrids, which show less food consumption with higher efficiency conversion. The aim of this study was to identify nutritionally efficient polyvoltine silkworm strains using the germplasm breeds RMW2, RMW3, RMW4, RMG3, RMG1, RMG4, RMG5, RMG6 and APM1 as the control. The 1st day of 5th stage silkworm larvae of polyvoltine strains were subjected to standard gravimetric analysis until spinning for three consecutive generations covering three different seasons on 19 nutrigenetic traits. Highly significant (p ≤ 0.001) differences were found among all nutrigenetic traits of polyvoltine silkworm strains in the experimental groups. The nutritionally efficient polvoltine silkworm strains were resulted by utilizing nutrition consumption index and efficiency of conversion of ingesta/cocoon traits as the index. Higher nutritional efficiency conversions were found in the polyvoltine silkworm strains on efficiency of conversion of ingesta to cocoon and shell than control. Comparatively smaller consumption index, respiration, metabolic rate with superior relative growth rate, and quantum of food ingesta and digesta requisite per gram of cocoon and shell were shown; the lowest amount was in new polyvoltine strains compared to the control. Furthermore, based on the overall nutrigenetic traits utilized as index or ‘biomarkers’, three polyvoltine silkworm strains (RMG4, RMW2, and RMW3) were identified as having the potential for nutrition efficiency conversion. The data from the present study advances our knowledge for the development of nutritionally efficient silkworm breeds/hybrids and their effective commercial utilization in the sericulture industry.

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