In vitro selection of rhizobacteria for control Diplodia maydis cause of ear rot disease in maize

Abstract

Rahma H, Arneti, Nofrianti S. 2018. In vitro selection of rhizobacteria for control Diplodia maydis cause of ear rot disease in
maize. Pros Sem Nas Masy Biodiv Indon 4: 225-230. Maize is an important food crop in Indonesia both for consumption and for animal
feed. One of the plant-disturbing organisms in corn plants is a fungus Diplodia maydis (Barkeley) Saccardo which causes cob rot.
Biological control using rhizobacteria is one alternative for controlling D. maydis. The objective of this research was to get the
rhizobacterial of maize plant that has the ability as antagonist to D. maydis. The research was carried out in 2 stages, the first was the
ability of 16 rhizobacteria isolates to inhibit the growth of D. maydis. Second Rhizobacteria inhibitory test on D. maydis used an
experimental method with a completely randomized design using 11 treatments and 4 repetitions. Rizobacteria were selected based on
their inhibitory effect on D. maydis using the dual culture method. Activity test of bioactive compounds from rizobacterial supernatant
using disc diffusion and medium poisoning method. The results showed that isolate KJTSB 7.2 and LMTSA 5.4 have the ability as an
antagonist with inhibitory ability in dual culture method of 51.10% and 50.00%. The antibiosis test of supernatant bioactive compounds
of these isolates with disc diffusion method was 7.77 and 17.73%. Meanwhile the dry weight of D. maydis in the antibiotic test using
medium poisoning method was 0.12 g and 0.18 g with an effectiveness of 82.85% and 74.28%.