Silkworm larval growth, cocoon yield and silk quality as affected by micronutrient application in mulberry

An experiment was conducted at field No. 68 of Eastern Block, Department of Sericulture, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Coimbatore, to evaluate the impact of soil application of micronutrients in mulberry on silkworm larval growth, cocoon yield and quality. The experiment was laid out in randomized block design (RBD) with three replications. Different single and combined soil applications of 25 kg ZnSO₄ ha⁻¹, 50 kg FeSO₄ ha⁻¹, 25 kg MnSO₄ ha⁻¹ and 10 kg Borax ha⁻¹ were done in mulberry. Treatment wise leaf samples were collected and fed to silkworm. In cross breeds, (Multivoltine) combined soil application 25 kg ZnSO₄ ha⁻¹ + 50 kg FeSO₄ ha⁻¹ + 25 kg MnSO₄ ha⁻¹ and in double hybrid races (Bivoltine) of silkworm, combined soil application of 25 kg ZnSO₄ ha⁻¹ + 50 kg FeSO₄ ha⁻¹ + 25 kg MnSO₄ ha⁻¹ + 10 kg borax ha⁻¹ in mulberry had remarkable improvement in V instar larval weight, single cocoon weight, shell weight, silk filament length, denier, renditta and cocoon yield. Therefore micronutrient application was beneficial for the growth and productivity of silkworm.