Study the Effect of Some Alcoholic Plant Extracts on Inhibition the Egg Hatching and Its Biological Effects on The Subsequent Stages of Teranychus Urticae Koch

The study included testing the biological effect of alcoholic extracts of three plants separately and the plants are Cabbage, Cauliflower, and Leek on two-spotted spider mite eggs. The concentrations used were (0, 0.5, 1, 2, 3, 4 and 5%) by direct spraying method, and the percentage of eggs hatching was read after (24,48,72, and 96) hours of treatment, equivalent to (4, 5, 6 and 7) days after oviposition. Furthermore, the study showed that there are significant effects of extracts in inhibition of the eggs hatching, where the lowest percentage of eggs hatching (the highest inhibition percentage) for the treatment was 5%. While the hatching percentage of the Cabbage extract was(0, 0 and 1%) as the inhibition percentage of eggs hatching (100, 100, 99 and 99) and for Leek (0, 2, 2 and 0%) is equivalent to inhibition percentage: (100, 100, 98 and98%) and for Cauliflower was (0%) that equal to inhibition percentage 100% for the four readings respectively.The highest percentage of eggs hatching (the lowest inhibition percentage) was for the comparison treatment (0%). Through increasing the concentration of extracts, the inhibition percentage of eggs hatching increases due to the increase in the percentage of active compounds present in them, which led to inhibition of hatching and ending the pest life cycle, especially with the high concentrations of each extract. As for the subsequent stages of the hatched eggs that treated with the Cabbage extract for high concentrations, resulted in dead larvae. Moreover, at lower concentrations, a few numbers of larvae developed into nymphs, most of which died, and the rest developed into an adult which died immediately after developing. As well as, the eggs treated with Leek extract, with the difference that the resulting nymphs all died and did not develop, while all concentrations of the Cauliflower extract, a few numbers of hatching eggs resulted in larvae died immediately after hatching. Whereas, the larvae resulting from eggs hatching the comparison treatments continued their development down to the adult stage from female and male.