Abstract
A field experiment was carried out in Nubaria and Kafr El-Sheikh regions to predict the main piercing-sucking insects and their associated predators, the impact of certain weather factors on them, the partial correlation on these studies and the role of predators in the control of Bemsia tabaci were discussed in Egyptian soybean fields during the 2020 and 2021 seasons. Results showed the distribution of population density and frequency of occurrence for piercing-sucking insects that included (Bemis ia tabaci Genn.; Aphis gossypii Glover; Nezara viridula L. and Empoasca app.) and predators that included (Chrysoperla carnea Steph.; Coccinella undecimpunctata L., Paederus alfierii, Orius sp. and True spiders) on soybean plants. The mean number of pierc ing-sucking insects and associated predators was less in Nubaria than Kafr El-Sheikh region and Empoasca app. disappeared in Nubaria region. The highest frequency of occurrence was Bemisia tabaci insect and Chrysoperla carnea predator during the study. The best time to implement the role of integrated pest management was in August, when the predator/B. tabaci ratio was high est. The partial correlation coefficient value was highly significant between temperature and B. tabaci and C. undecimpunctata in Nubaria while N. viridula and Empoasca in Kafr El-Sheikh during 2020 but 2021 season, it was highly significant with B. tabaci, A. gossypii, N. viridula, P. alfierii and Orius sp. in Nubaria whereas Ch. carnea and True spiders in Kafr El-Sheikh during 2021. Relative humidity was highly significant with Empoasca spp. and true spiders, in Kafr El-Sheikh during 2020 while wind speed was highly significant with B. tabaci in Kafr El-Sheikh during 2020 and with Nubaria during 2021. The role of the main insect predators in the control of piercing-sucking insects was highly significant between P. alfierii and N. viridula in Nubaria, while Kafr El-Sheikh was Ch. Carnea with B. tabaci and N. viridula, then C. undecimpunctata with A. gossypii and N. viridula and True spiders with B. tabaci, and N. viridula during 2020, next 2021 season, P. alfierii with B. tabaci in Nubaria region then Kafr El-Sheikh was Ch. Carnea and True spiders with B. tabaci, N. viridula and Empoasca spp. these means that there are another factors effect on the relationship between insects and predators population.