Morpho-physiological and molecular characteristics of bacteria causing stalk rot disease on corn in Gorontalo, Indonesia

Abstract. Suriani, Patandjengi B, Muis A, Junaid M, Mirsam H, Azrai M. 2023. Morpho-physiological and molecular characteristics of bacteria causing stalk rot disease on corn in Gorontalo, Indonesia. Biodiversitas 24: 1749-1758. Stalk was observed Gorontalo with typical symptoms, such as soft the stalk, leaf wilting, plant death. This study aimed to characterize corn. Samples infected plants were collected identified morphologically, physiologically, molecularly. The results showed that nine bacterial isolates isolated from plants. All positive hypersensitive responses tobacco leaves. In comparison, only two (BGO1 BGO4) pathogenicity tests However, BGO4 isolate caused highest incidence a faster incubation period. gram-negative white-gray colored colonies. Physiological characterization also showed: catalase indole, oxidase negative, fermentative oxidation, potato, non-fluorescent, sensitive erythromycin. addition, it can grow at 37-40°C 5% NaCl, producing protease lecithinase enzymes. rice, corn, sorghum, foxtail millet, celery, Aloe vera. Morpho-physiology diagnostic amplification DNA by PCR using Dickeya-specific primers (ADE1/ADE2) belongs genus Dickeya. Further analysis 16S rDNA universal primer 27F/1497R successfully amplified band measuring ±1300 bp. Phylogenetic same group Dickeya zeae strain MS32 Taiwan, DZ15SB01 (Thailand), HNJF02 (China), coefficient genetic distance ranging 0.001 0.002. is first report D. infecting Gorontalo.