Evaluation of biological control agents for managing squash powdery mildew under greenhouse conditions

Résumé

Abstract Squash (Cucurbita pepoL.), is one of the most important vegetable crops for human nutriment in Egypt and the world. One of the most serious diseases that infect squash and cause yield losses was powdery mildew, caused byPodosphaera xanthisii. The aim of this study was to investigate the role ofBacillus subtilis,Paenibacillus polymyxa(109cell ml/1),Trichoderma harzianum,T. album,T. virideandT. hamatum(107spore ml/l) for controlling disease under greenhouse conditions. Results indicated that all treatments significantly inhibited the conidial germination ofP. xanthiithan control in vitro and decreased the incidence and disease severity after spraying with the bio-agents on squash plants under greenhouse conditions. The fungicide, Topas-100 (10.0% penconazole “w/v” [(R,S-1-(2-(2,4-dichlorophenyl)-Q pentyl)-1H-1,2,4-triazole]), followed byB. subtiliswas highly significant for decreasing disease incidence (2.8 and 5.3%, respectively) and disease severity percentage (3.5 and 4.8%, respectively) than the control. The activities of biochemical changes, i.e., peroxidase, polyphenol oxidase, and total phenols, were significantly upregulated as results of most treatments. Also, bio-agent treatments caused significant increase in yield characteristics of squash plants such as fruit number/plant and fruit weight/plant than control.B. subtilisrecorded the highest increase (110.9% and 98.7%) in fruit number and fruit weight/plant than control.

Citer ce document

Accès au document

Ce document est hébergé sur son dépôt institutionnel d'origine.

Auteur(s)

Statistiques

Consultations : 1

Téléchargements : 0