Effect of Plant Growth Promoting Rhizobacteria (PGPR) on Increasing the Activity of Defense Enzymes in Tomato Plants

Growth-promoting rhizobacteria are non-pathogenic bacteria that can induce plant defense through induction of systemic resistance which can then activate defense enzymes such as Polyphenol Oxidase (PPO), Peroxidase (PO) and Penil Alanine Amoliase (PAL). This study aims to determine the activity of the PPO, PO and PAL defense enzymes with selected PGPR isolates. This research was carried out at the Microbiology and Greenhouse Laboratory of the Faculty of Agriculture, Andalas University, Padang, and then tested at the PAU IPB Laboratory, West Java Indonesia in March-July 2020. The results showed that tomato leaves that had been treated with PGPR showed that PGPR had the potential to increase the PO enzyme 0.072 µg · mL – 1, PPO 0.0009 µg · mL – 1 and PAL 14.15 µg · mL – 1. EAB 2.1 isolate is best isolate can increase PPO, PO and PAL.