Exploring the effect of some plant probiotic bacteria isolated from salty and dry areas in control Phytophthora drechsleri regent disease pistachio gummosis in vitro

In this study, the effect of some plant probiotic bacteria were isolated from salty and dry areas were investigated in control the fungus agent pistachio gummosis disease and growth stimulating properties. 200 bacteria isolates were isolated from rhizosphere and non rhizosphere areas of pistachio trees and weeds in the margins of gardens in Kerman province. Thirty isolates were able to endure the used salt tolerant. The bacteria isolates were investigated at the hypersensitivity reaction (HR) test. Three of them were eliminated due to positive result of HR and the other were studied more as antagonist agents. In the early stage the biocontrol ability of these isolates against the fungus causing pistachio gummosis diseases such as Phytophthora drechsleri were surveied. For this purpose, inhibition zone test (antibiosis) was performed that antagonist isolates showed significant effect on P. drechsleri growth. In the secondary stage, The ability of isolates to produce some biocontrol metabolites including protease, antifungal volatile compounds and hydrogen cyanide were evaluated. Growth stimulating characteristics of these isolates incloding amount of siderophore and IAA production were measured. soluble ability of insoluble mineral phosphate was surveied, too. The results showed from 27 studied isolates for growth stimulating properties, %80 at least had one of the PGPR properties. %64 of the isolates were productive of siderophore, %80 productive of IAA, %45 having solving ability of insoluble mineral phosphate. The isolates C16, F47 and G11 as superior isolates of this study in vitro were successful in controlling the disease.