تأثير عزلتين من البكتيريا المحفزة لنمو النبات PGPR في نسبة وشدة وأعراض الإصابة على نباتات الفليفلة ضد فيروس التجعد البني على ثمار البندورة ToBRFV

Abstract

The study was conducted to study the effect of treating pepper plants with two isolates of plant growth promoting rhizobacteria (PGPR): Bacillus subtilis, Bacillus sp. strain (ABC3,cbs123) on the infection rate, severity of infection, and symptoms of infection of pepper plants with Tomato brown rugose fruit virus (ToBRFV) in protected cultivation conditions, where seeds of pepper hybrids (Dallas–Bravo) were soaked for two hours in bacterial suspension at a concentration of 10⁹ CFU/ml for each of the two bacterial isolates according to the studied treatments with occasional stirring, and then the seedlings were treated with 10 ml of the same concentration after transferring them to the plastic house, where the results showed a reduction in the percentage, severity, and symptoms of apparent infection on the two studied pepper hybrids (Dallas–Bravo). In the Dallas hybrid, treatment with the bacterial isolate Bacillus subtilis and infection with the virus reduced the infection rate by 8%, while treatment with the bacterial isolate Bacillus sp. Infection with the virus reduced the infection rate by 20%, while treatment with a mixture of Bacillus subtilis and Bacillus sp. bacteria and infection with the virus reduced the infection rate by 15%. As for the Bravo hybrid, treatment with the Bacillus subtilis bacterial isolate and infection with the virus reduced the infection rate by 20%, while treatment with the Bacillus sp. bacterial isolate and infection with the virus reduced the infection rate by 40%, while treatment with a mixture of Bacillus subtilis and Bacillus sp. bacteria and infection with the virus reduced the infection rate by 25%. Thus, we note that the Bacillus sp. bacterial isolate was the most effective in reducing the infection rate on both hybrids studied (Dallas - Bravo).