Traditionally, various agricultural practices are used to increase agricultural yield along with insecticides. Excessive utilization of insecticides in crops has harmful effects on natural predators by reducing their efficiency as biological control agents. In this study, the harmful effects of insecticides such as chlorpyrifos and acephate on the web-building behavior of Argiope trifasciata were observed with different concentrations and time gaps. The mortality rate of spiders was also recorded; for example, 30% mortality was observed after exposure to field-rate concentration of acephate, while 20% and 5% mortality were observed after exposure to intermediate and half-field concentrations of acephate, respectively. Similarly, 50% mortality was observed at field-rate concentration of chlorpyrifos. However, 20% and 10% mortality were observed after the application of chlorpyrifos at intermediate and half-field concentrations, respectively. Both insecticides maximally influenced the web parameters after 72 h of exposure at field-rate concentration. However, chlorpyrifos adversely affected the web parameters compared to acephate.
Ashraf et al. (Wed,) studied this question.