Isolation and identification of the microorganisms associated with some nymphs and adults of the dubas insect (Ommatissus lybicus) and evaluation of their effectiveness in the laboratory

Abstract

The study aimed to isolate and diagnose the fungi associated with the Dubas insect and test their effectiveness in resisting this insect under laboratory conditions. The pest is feeding on leves of date plam tree. That couse dameg to dates. The results showed the presence of fungi associated with the samples of Dubas nymphs and adults in all samples included in the survey, as there was a difference in the percentage of frequency and presence of the fungi, as the Aspergillus fungus excelled with the highest percentage of appearance and frequency of 57.14 and 48.13%, respectively. The results of the pathogenicity test of the fungi isolated from Adults and nymphs of Dubas under laboratory conditions, the T2 (Penicillium sp.) fungus isolate in sample No. 1 was distinguished by giving it a high mortality rate of 6.58% , followed by the T1 (Aspergillus sp.) fungus isolate in the same sample, where its rate reached 4.49% compared to the control treatment in which only distilled water was used, as its rate reached 0.75%. The results of the identification of fungal isolates pathogenic to Dubas insects showed that 4 fungal isolates excelled in the pathogenicity test in the laboratory, and according to the taxonomic keys, they belonged to the species Aspergillus funigatus, A. versicolor, Penicillium janthinellum, and P. amrantiogriseum.