Effect of Physical Factors and Parasitoid Aphidius transcaspicus on Population Dynamics of Green Peach Aphids Myzus persica on The Potato Crop.

Abstract

A field study conducted in the laboratory and laboratories College of Agriculture / University of Tikrit season spring 2010 fields to study the effect of natural factors and the parasitoid Aphidius transcaspicus in a dynamic population of green peach Myzus Persicae the potato crop. The results showed that the first appearance of the green peach aphid M. Persicae had scored at the end of March, until it reached its peak in the last third of the month of April and the census was 257 insects / 50 a leaf, has coincided with the first appearance of an intruder A. transcaspicus in the first week of the month of April by the intrusion on the individual aphids reached 5% and it continued the number of parasitoid increase until it reached its peak in the first week of May by in the rate of parasitism 56% Which contributed to the low population density of those even reached to 93/50 of a leaf .at the end of the month of May did not record any injury insect and parasitoids. Results indicated that there is a negative correlation between the density of aphids and temperatures reaching (-0.156) and a positive correlation with relative humidity and wind speed and rate of parasitism rate of 0.242, 0.159 and 0.018 respectively. The study showed superiority of the mixture (honey and jelly and water) in adult nutrition which was launched in the potato field, as the average number of mummies totaled 40.667 / 12 plant.