Abdullah, R. (2019). Insecticidal Activity of Secondary Metabolites of Locally Isolated Fungal Strains against some Cotton Insect Pests. Journal of Plant Protection and Pathology, 10(12), 647-653. doi: 10.21608/jppp.2019.79456
Reda R Abdullah. "Insecticidal Activity of Secondary Metabolites of Locally Isolated Fungal Strains against some Cotton Insect Pests". Journal of Plant Protection and Pathology, 10, 12, 2019, 647-653. doi: 10.21608/jppp.2019.79456
Abdullah, R. (2019). 'Insecticidal Activity of Secondary Metabolites of Locally Isolated Fungal Strains against some Cotton Insect Pests', Journal of Plant Protection and Pathology, 10(12), pp. 647-653. doi: 10.21608/jppp.2019.79456
Abdullah, R. Insecticidal Activity of Secondary Metabolites of Locally Isolated Fungal Strains against some Cotton Insect Pests. Journal of Plant Protection and Pathology, 2019; 10(12): 647-653. doi: 10.21608/jppp.2019.79456
Insecticidal Activity of Secondary Metabolites of Locally Isolated Fungal Strains against some Cotton Insect Pests
plant protection research institute, Agriculture research center, Dokki, Giza
Abstract
Microbial pest control is one of the best alternatives to chemical insecticides. Beauveria bassiana and Trichoderma harzianum are important entomopathogens of many insect pests. Cotton leafworm (Spodoptera littoralis) and aphids (Aphis gossypii) are the most destructive pests in crop production such as cotton, cabbage, tomato, potato, and lettuce. The present study sought to isolate both fungal strains (B. bassiana and T. harzianum) and extract their secondary metabolites by ethyl acetate then evaluate the efficacy of crude extract against both insect pests (S. littoralis and A. gossypii). Also, Gas chromatography-mass spectrometry(GC-MS)analysis was conducted to both extracts of isolated fungi. The results indicated that both extracts of tested fungi have insecticidal activity against both tested insects. B. bassiana extract was more toxic against both insects than T. harzianum. The extract of T. harzianum wasmore toxic against A. gossypii more than S. littoralis. The LC50 values of B. bassiana and T. harzianum against S. littoralis were 575 and 3238 ppm respectively but, they were 226 and 389 ppm against A. gossypii respectively. GC-MS analysis indicated the presence of some identified compounds as insecticides in both extracts of fungi such as: n-Hexadecanoic acid; Hexadecanoic acid, methyl ester; 9,12-Octadecadienoic acid, methyl ester, (E,E)-; Tetradecanoic acid, 12-methyl-, methyl ester; 7,10-Octadecadienoic acid, methyl ester and trans-13-Octadecenoic acid. This study recommended that the ethyl acetate extract of both tested fungi can be used as an alternative of chemical pesticides to control A. gossypii but in the case of S. littoralis can be used the extract of B. bassiana only.