Treatment Mulberry Trees with Some Insecticides and Its Effect on the Productivity of Silkworm, Bombyx mori L.

During the spring season of 2019, the effect of two insecticides (Cymbush®&Tracer®) on larvae of Bombyx mori  L. were studied at Plant Protec. Dept. Fac. of Agric., Fayoum Univ. Insecticides were sprayed on mulberry trees by concentration 1ml/l . of Cymbush® and 0.1ml/l. of Tracer®  .Mulberry leaves were harvested on to three times (after 3,6,9,12 days).Results show that, the 5th instar larval mortality percentages increased , where data ranged between 18.30% in Cymbush® and 10.21% in Tracer®  compared to 9.93% in control. While cocooning percentages, cocoon shell ratio and silk productivity were decreased when comparing to control, where data ranged between 74.00% in Cymbush®, 89.08% in Tracer®  , 12.00% in Cymbush®,19.07% in Tracer®  and 1.021cg/day in Cymbush®, 1.800cg/day in Tracer®  , respectively compared to 93.00%, 19.77% and 1.910cg/day in control, respectively.