Population Fluctuation of Cotton Aphid (Aphis gossypii Glover) on Roselle Plants in Relation with Certain Biotic and Abiotic Factors

Abstract

This research work was conducted to describe the relationship between the population density of the cotton aphid on roselle plants and its accompanied predators, some quantities characters of roselle plants and the main weather factors at Awlad -Sakr district, Shakira Governorate, Egypt in 2018 and 2019 growing seasons. Aphids were collected by using plant sample technique. Results indicated that A. gossypii showed seven peaks of activity, the highest one ( 1453 individuals /sample) was on the 8 th of August in the first season. In the second season A. gossypii recorded five distinct activity peaks the highest of them took place on the 23 rd of July with 5068 individuals /sample. Simple correlation, partial regression and coefficient of determination between aphid population and the aforementioned factor were evaluated. Statistical analysis results showed that these factors played a conspicuous role in detecting the activity of cotton aphid during the two investigated seasons of the study.