Fereshteh Amirmohammadi, Jalal Jalali Sendi Seyyed H. Hosseini Moghaddam and Moinnodin Mavvajpour
Several technologies exist for improvement of cocoon including the use of natural chemicals such as plants possessing phytoecdysteroids. In the present investigation the methanol extract of the plant Pteridium aquilinum (Dennstaedtiaceae), was used in 3 concentrations (i.e. 1.25, 2.5 and 5%) dissolved in distilled water and sprayed on leaves fed on first two days of 3th, 4th, and 5th instar larvae of Bombyxmori in 3 replications of 100 insects in each replicate and a control with distilled water treatment. Results showed that, the highest silk gland weight belonged to control (0.45±0.15g), the highest cocoon weight (60.235±67.98g), cocoon shell weight (19.5±2.59g), number of best cocoon (53) was that of 2.5% concentration. However, 1.25% concentration showed significant differences with control and other concentrations in terms of metabolites like: cholesterol (112.16±47.46mg/dl), urea (349.37±44.78mg/dl), glucose (565.65±77.26mg/dl),LDH (17153±1014.38U/min). ALP (0.006±0.0004μmole/min/l) was recorded the highest for 5% concentration compared with control and other concentrations. However, AST and ACP did not show differences among treated and control insects. Various results were obtained on nutritional efficiency, and cocoon spinning.The possible significance of these results is discussed
