Effect of endophytic bacteria and arbuscular mycorrhizal fungi on bacterial spot disease of pepper and some plant growth parameters

The aim of this study was to investigate the effects of the single and dual inoculations of Arbuscular Mycorrhizal Fungus (AMF) Glomus mosseae and two rhizobacteria (Pseudomonas fluorescens WCS365 and Pseudomonas sp. V31Y4) on the growth parameters, chlorophyll, phosphorus content, and the bacterial leaf spot disease (Xanthomonas euvesicatoria-Xe) of The seeds of pepper cv. "Demre" was sowed in sterile peat growing medium amended with AMF in the climate chamber. Rhizobacteria were applied to pepper seedlings in two different periods by drenching method. The pathogen inoculated on the leaves by spraying. 1-6 scales measured disease severity at the end of the study. The pepper. It has been observed that both single and double applications of biological control elements affect plant growth positively. The treatment with AMF was also found to have higher root fresh weight. However, it was found that single and dual applications of AMF and WCS365 increased P content compared to control plants. The chlorophyll content was higher than controls groups in pepper plants in all application of biological control elements. Root colonization of the AMF isolate decreased in combinations with the pathogen but increased in inoculation with WCS365. Single bacteria applications were more effective than AMF application in suppressing the disease severity; also AMF+WCS365+Xe triple combination was found to be more successful efficacy than all application groups. Key words: Pepper, Mycorrhizal, PGPR, Xanthomonas euvesicatoria.