COMBINED INOCULATION OF ARBUSCULAR MYCORRHIZAL FUNGI, PSEUDOMONAS FLUORESCENS AND TRICHODERMA SPP. FOR ENHANCING DEFENSE ENZYMES AND YIELD OF THREE PEPPER CULTIVARS

Field experiment was carried out at the experimental station of Szent Istvan University, Godollo, Hungary to explore the impact of arbuscular mycorrhizal fungi only alone or together with Trichoderma and plant growth-promoting bacteria on defense enzymes and yield of three pepper varieties. The seven inoculation treatments consisting of arbuscular mycorrhizal fungi (AM), Trichoderma (Tri), plant growth promoting bacteria (Pse) and their combinations (AM+Tri; AM+Tri+Pse; AM+Pse) together with three pepper hybrids and non-inoculation (control) plants were arranged in a randomized complete block design. Defense enzyme activities polyphenol oxidase (PPO), peroxidase (POD), superoxide dismutase (SOD), catalase (CAT) of various treated plants were measured just before flowering, representing the most sensitive stage of plants. The results showed that AM+Tri+Pse treatment enhanced the yield most among microbial inoculations. Highest yield was recorded in the triple treatment in Karpex cultivar, however, Karpia and Kaptur variety obtained more improved yield by microbial inoculations. Defense enzymes activities generally were most induced in the combination of three inoculants in cultivars whereas different responses in induction of defense enzymes were found in other microbial treatments, depending on specific interactions between microbe and pepper genotype. These results suggested that the triple application brought more benefits to the host plant.