Effect of certain entomopathogenic fungi and nematode on the desert locust Schistocerca gregaria (Forskal)

摘要

The efficiency of entomopathogenic fungi, Beauveria bassiana and Entomophthora sp. as well as the nematode, Steinernema carpocapsae , against 3rd, 5th instar nymphs and adults of the desert locust, Schistocerca gregaria (Forskal) had been studied under laboratory conditions. Fungi at the concentrations 2.3×10 5 , 7×10 7 , 3.9×10 9 and 4×10 5 , 6.7×10 7 , 2.2×10 9 spores/ml and nematode at 5000, 2500, 1250IJS/ml, respectively were applied on the desert locust by two different treatment methods; spray and soil application. The obtained results revealed that all the locust nymphs and adults were susceptible to fungi and nematode with high mortality rate records. The nematode killed approximately 100% of the tested locust individuals within 3–5days postinfection and was found more effective than fungi in less time. On the other hand entomopathogenic fungi and nematode were found to be more effective when applied on the soil surface rather than spray treatment. This was common at any concentration used. Based on mortality percentages, all tested fungi and nematode had high potentials for biocontrol agents against S. gregaria .