Isolation and selection of the Pseudomonas sp. strain with high antagonistic activity against the fungus Colletotrichum scovillei causing chili anthracnose disease in Lam Dong Province

Abstract

Anthracnose disease caused by Colletotrichum species has appeared in many crops, particularly chilies which have been heavily affected. In Viet Nam, Lam Dong Province is one of the most chili planting areas then it is enormously impacted on chili production. Currently, biological methods have been increasingly used in plant disease prevention due to their effectiveness and safety. Specifically, Pseudomonas species have been widely studied and become the great potential candidates owing to their antagonistic ability against the anthracnose causing fungi. For this reason, the research of isolation and selection of the Pseudomonas species strain possessing the highest inhibitory activity against the fungus Colletotrichum scovillei, giving rise to Chili anthracnose disease in Lam Dong Province, was conducted. From 12 soil samples, 19 isolates were initially categorized as Pseudomonas species. Out of all candidates, the LD3.1 strain exhibited the strongest inhibitory effectiveness on the development of Colletotrichum scovillei (60.78% after 15 days). The molecular identification result based on 16S ribosomal DNA revealed that LD3.1 is identical to Pseudomonas putida (100%).