Effects of Thrips (Pseudodendrothrips mori Niwa) Infested Mulberry Leaves on Silkworm Growth and Commercial Cocoon Parameters

In mulberry orchards in northern part of Iran, thrips is a dominant pest and causing a lot of damage to the mulberry. The effect of pest on bio-chemical parameters of mulberry leaf of two varieties viz. Kenmochi and Ichenoise and also the effect of feeding of infested leaves on rearing performances have been studied. For the study, six plots of 200 m2 area of both the varieties were selected and three of them, of each variety, were sprayed with 0.5% Metasystox at a peak period of occurrence of nymph population to obtain the good healthy leaf without thrips infestation. Another 3 plots were left without pesticide spray to obtain infested leaves so as effect of infestation on chemical parameters of leaf and effect of infested leaves on rearing performance could be studied. During rearing, larvae were fed with good quality of mulberry leaf while another lot were fed with infested leaves. The results showed that there was a decrease in nitrogen, phosphorus, potassium and protein contents of leaves by 2.5, 10.8, 18.7 and 12.5%, respectively due to infestation and the decrease in these parameters was more in Kenmochi. There was also a significant decrease in total co coon production, cocoon weight, pupal weight, and shell weight due to feeding of infested leaves. However, there was no significant difference in shell ratio between the lots fed with healthy and infested leaves

Bio-Economic Changes Due to Long Time Treatment of Carbendazim on Mulberry Silkworm (Bombyx mori L.

The effect of fungicides on silkworm larvae was analyzed with regard to the fact that these beneficial insects are usually affected by fungicides, Daily feeding on 1 and 2g/liter of carbendazim, a systemic fungicide, did not have significant effects on larval and pupal mortality. However the weight of the treated larvae showed considerable weight decrease up to 37% weight.. All the economic traits of male and female adults treated with fungicide decreased but this decrease is not significant in cocoon shell weight and hatching percentage. The comparison of means using Tukey test at 5% confidence level did not show any effect related to the concentration

Estimation of Performance and Genetic Parameters of Ten Chinese and Japanese Silkworm Hybrids in a Crisscrossing System

Performance of five Chinese commercial lines of silkworm like 32, 104, 110, 152, 154 and five Japanese ones such as 31, 103, 107, 151, 153 were investigated at four rearing periods of two spring and two summer seasons. Total hatch, rearing steps, recording and experimental activities were conducted under standard conditions of ESCAP (1993). The results indicated that maternal base effect all of effects in model (generation, genus and hybrid group) was significant (