EXISTENCE OF BEAUVERIA BASSIANA (BALSAMO) VULLEMIN AS ENDOPHYTE ON ONION PLANTS AND ITS PATHOGENICITY (IN VITRO) AGAINST ONION THRIPS, THRIPS TABACI LIND. (THYSANOPTERA: THIRPDAE)

Authors : Nihal BAGY, Mohaemd ABDELRAHMAN, Mohamed MORSY, Gaber ABOUELHAGAG

Pages : 15-24

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Publication Date : 2018-06-15

Article Type : Research Paper

Abstract :Beauveria bassiana insert ignore into journalissuearticles values(Balsamo); was successfully isolated from the leaves of onion plants, Allium cepa Lind. cultivated in the Experimental Farm of AssiutUniversity. Morphological characters of the fungus were described. Moreover, the pathogenicity of this isolate was assayed insert ignore into journalissuearticles values(dipping technique); against onion thrips, nympal and adult stages insert ignore into journalissuearticles values( In vitro );. Six concentrations insert ignore into journalissuearticles values(13x10 4 , 29x10 4 , 42x10 4 , 64x10 4 , 86x10 4 and 104x10 4 conidia / ml); were used. Our results demonstrated that mortality increased as the conidial concentrations increased. It seems that the concentration of 104 x 10 4 conidia / ml is an effective to get sufficient mortality for the nymphal stage insert ignore into journalissuearticles values(92.50%); and adult stage insert ignore into journalissuearticles values(88.46%);. In general, results refer that B. bassiana isolated from onion leaves at the concentration of 104x10 4 spores/ml is effective to get about 90% mortality for the onion thrips regardless of the pest stage. Also, virulence of B. bassiana against onion thrips insert ignore into journalissuearticles values(nymphal and adult stages); elucidated that the fungus was more effective on nymphal than adult stage as indicated by low value of LC 50 and LC 95 . The present results reflect the potential role that can be played by B. bassiana endophyte in the biological control of thrips infesting onion plants under field conditions.
Keywords : Beauveria bassiana, endophyte, onion plant