Impact of Leaf-age on Economic Traits of Mulberry Silkworm (Bombyx mori L.)

Aims: This study aimed to investigate the impact of feeding mulberry leaves of different maturity stages—tender, medium, and coarse—on the economic traits of bivoltine silkworms (Bombyx mori L.), with the goal of enhancing sericulture practices by identifying the most beneficial leaf types for feeding. Study Design: The experiment utilized seven treatments comprising various combinations of mulberry leaf ages: tender (T1), medium (T2), coarse (T3), and their combinations (T4-T7). Each treatment was replicated three times, following a randomized block design. Place and Duration of Study: The experiment was conducted during the monsoon season of 2020-21 at the Department of Agricultural Entomology, College of Agriculture, Latur, under Vasantrao Naik Marathwada Krishi Vidyapeeth, Parbhani, Maharashtra. Methodology: Disease-free layings of FC2 X FC1 bivoltine double hybrid silkworms were reared on different maturity mulberry leaf combinations (variety V-1), and parameters such as larval weight, cocoon weight, single shell weight, cocoon shell ratio, cocoon yield, filament length, filament weight, denier, disease incidence, and effective rate of rearing were measured. Results: Feeding silkworms with tender leaves (T1) resulted in the highest values for larval weight (38.82 g), cocoon weight (1.94 g), single shell weight (0.37 g), cocoon shell ratio (19.21%), cocoon yield (18.68 kg per 10,000 larvae), filament length (922.33 m), filament weight (0.28 g), denier (2.76), effective rate of rearing (98.40%), and lower disease incidence (1.30%). Conversely, feeding coarse leaves (T3) led to the lowest values across these parameters. Conclusion: The study highlights the significance of mulberry leaf quality, particularly tenderness and moisture content, in optimizing economic traits in sericulture. Tender leaves consistently supported superior economic traits compared to medium and coarse leaves. These findings suggest that managing leaf quality can significantly enhance silk production and quality in Bombyx mori L., highlighting the nutritional advantages of tender mulberry leaves. Future research could explore additional factors affecting leaf quality and their specific impacts on silkworm development and silk characteristics.