The Effect of Leaves of Different of Mulberry Varieties on the Performance of Silkworm, Mazandaran Province

An experiment was conducted to study the effect on performance of silkworm Bombyx mori L., when fed by leaves of different mulberry varieties a CRD design with 12 tratments (including Kamasari, Kaeiryo Ichinose, Kaeerizhotezomigaeeshi, Tachibana, Ichinose, Chekemaoha, Yukishinogi, Shin Ichinose, Wasemidori, Roso, Kenmochi, as well as some local varieties in 4 replications. The larvae were reared under standard rearing protocols. Larval feeding and mounting durations, cocoon and such pupae traits as produced cocoon number; good, middle, low and double cocoon number, pupae vitality, and weight of cocoon types were recorded. Results showed that the nutritional effect of feeding of leaves of different mulberry varieties were significant on most investigated traits (P<0.01). The results showed that feeding with leaves of Shin Ichinose variety resulted in the highest cocoon weight of 10000 larvae, the highest average weight of a best cocoon, the highest larval weight in the 4th and 5th instar, the highest vitality percentage of pupae in the best cocoons along with the lowest larval period (P<0.01). On the other hand, larvae feding with local varieties, despite obtaining the highest average cocoon shell weight and the highest average cocoon shell percentage, resulted in the lowest vitality percentage of pupae in total cocoons, along with the longest larval period of mature larvae (P<0.01). Feeding, using Tachibana and Yukishinogi variety leaves resulted in the lowest cocoon weight of 10000 larvae, the lowest average shell weight of a best cocoon, the lowest larval weight and the longest larval period (P<0.01). Also Roso variety ended up with the lowest vitality percentage in best cocoons, the lowest number of cocoons and the lowest weight of best cocoons. Thus, Shin Ichinose variety was introduced as the most suitable variety while Tachibana, Yokishinogi and Roso varieties introduced as the undesirable ones.