Induction of resistance against powdery mildew by Beta aminobutyric acid in squash

The non-protein amino acid beta-aminobutyric acid (BABA) enhances squash resistance to microbial pathogens through potentiation of the squash defense responses. In the present study, we investigated the effects of BABA pretreatment on cucurbit powdery mildew disease. Three concentrations of BABA (0.5, 2 and 4 mM) as priming media and distilled water as control plants were used. The results showed that the 4 mM BABA was the most effective concentration to control the disease symptoms. The expression of PR-1 gene in relation to this pathogen was investigated and confirmed. Guaiacol peroxidase and Phenylalanine amonia-lyase enzymes activities increased in pretreated-inoculated squash plants. Bases on our results and regarding the adverse effects of fungicide on the environment, use of BABA as an environmentally safe agent is recommended as a valuable contribution to disease management.