Control of bacterial leaf blight and rice blast with antagonist microbial in the agroecosystem of irrigated rice

Bacterial leaf blight (Xanthomonas oryzae) and rice blast (Pyricularia oryzae) cause yield losses in rice production. Antagonist microbial application through seed treatment and foliar spray during rice growing stage is suggested to prevent the disease which is more reliable to reduce the disease incidence than curing it. This research aimed to determine the severity of bacterial leaf blight and rice blast among varieties that treated with antagonist microbial complex in the agro ecosystem of irrigated rice. Research was conducted in Kalibawang sub district, Kulon Progo, Yogyakarta, October 2018 to January 2019. The experimental design was randomized block design with 7 treatments and 4 replications. The treatments were the application of antagonist microbial complex formula A (Azotobacter vinelandii, Azospirillum sp., Bacillus cereus, Bradyzhizobium sp., and Methylobacterium sp. >10⁷ CFU/g) and formula B (Azotobacter chroococum, Azotobacter vinelandii, Azospirillum sp., Pseudomonas cepacia, Penicillium sp., and Acinetobacter sp. >10⁷ CFU/g) to several rice varieties (Inpari 9, Inpari 33, and Ciherang). Results shows that formula B had the lowest severity of bacterial leaf blight (14.44%) and leaf blast (6.94%) at Ciherang while formula A had the lowest panicle blast (6.55%). The highest yield (10.62 t/ha) was obtained from Ciherang treated with formula B.