Biological control of potato bacterial wilt disease caused by Ralstonia solanacearum using actinomycetes isolates

Document Type : Research and Review Papers

Authors

1 Plant Pathology Dept. Faculty of Agriculture, Sohag Univ. 71526, Sohag, Egypt

2 Plant Pathology Department Faculty of Agriculture Sohag University Sohag 82524 Egypt

Abstract

Ralstonia solanacearum is one of the most critical and widespread pathogenic bacteria that causes wilt disease in vegetable crops, including potatoes. In vitro study was conducted to screen potential actinobacterial isolates for their antibacterial activity against two isolates (Rs3 and Rs11) of bacterial wilt pathogen, R. solanacearum. Soil samples were collected from different localities. From collected soil samples, 45 morphologically distinct actinomycetes isolates were isolated. In the screening test, 7 isolates were selected, showing inhibitory activity against the pathogen. These seven efficient isolates were subjected to the cell-free suspension test. From the cell-free suspension test, only three cell-free suspensions of 3 isolates exhibited inhibitory activity against both pathogenic isolates. Isolate ACT27 exhibited the highest effect on both tested Rs3 and Rs11 pathogenic isolates, followed by ACT7 and ACT9. Whereas isolates ACT20, ACT33, and ACT13 showed the intermediate effect on both tested pathogenic isolates Rs3 and Rs11. Data also indicated that isolate ACT22 exhibited a minor effect on both tested Rs3 and Rs11 pathogenic isolates. Data also indicated that only three cell-free supernatants of isolates (ACT7, ACT9, and ACT27) give an inhibitory effect against both tested R. solanacearum pathogenic isolates. They are not varied so much in the degree of their activity. In this study, it can be concluded that actinomycetes isolates have antibacterial activity against this target pathogen. Also, the investigated isolates can be used through detailed further in vivo tests.

Keywords

Main Subjects