Serrtia plymuthica Strain A21-4: A Potential Biocontrol Agent Against Phytophthora Blight of Pepper

Shen, Shun Shan; Kim, Jin Woo; Park, Chang Seuk

The Plant Pathology Journal 2002;18(3):138-141.
Published online June 30, 2002.

Serrtia plymuthica Strain A21-4: A Potential Biocontrol Agent Against Phytophthora Blight of Pepper

Shun Shan Shen, Jin Woo Kim, Chang Seuk Park

Abstract

A promising biocontrol agent, A21-4, against Phytophthora blight of pepper was selected from 351 bacterial isolates collected from rhizosphere soils and roots of onion (Allium fistulosum L.). The isolate A21-4 was identified as Serratia plymuthica based on its 16S rRNA sequence and key characteristics as compared with that of an authentic culture of S. plymuthica (ATCC No. 6109D01). The isolate readily colonized on roots of various crops including pepper when inoculated on seed and root. Strain A21-4 showed narrow spectrum of antibiotic activity, as revealed in its strong inhibitory activity to the genera Pythium and Phytophthora, but not to Fuasrium and Rhizoctonia. In pot experiments, none of the pepper seedlings treated with A21-4 were infected by Phytophthora capsici, while 86% of the control plants were killed by the pathogen.

Key Words: biocontrol, pepper, root colonization, Serratia plymuthica