Features Production Research
New method may thwart peach diseases

July 23, 2008 – Natural bacterial
extracts may offer some assistance to peach growers in treating fungal
diseases, such as brown rot in peaches.

July 23, 2008 – Natural bacterial extracts may offer some assistance to peach growers in treating fungal diseases, such as brown rot in peaches.
Agricultural Research Service (ARS) scientists in Byron, Georgia, are using these substances as a safe and effective alternative to chemical fungicides. 

ARS entomologist David Shapiro-Ilan and plant pathologist Charles Reilly at the Southeastern Fruit and Tree Nut Research Laboratory in Byron developed these natural pesticides to control peach diseases. Although bacterial methods for controlling fungi are not new, the ARS bacterial compounds have never been used to control disease in this commodity. 

In these studies, Shapiro-Ilan and Reilly used compounds obtained from two genera of bacteria, Xenorhabdus and Photorhabdus. They were found to be effective against common peach disease organisms that cause significant damage. The two scientists tested compounds from a variety of bacterial strains and species to determine which would be most potent.

The results indicated that X. bovienii and P. luminescens (VS) bacterial compounds generally exhibited the greatest suppression of plant pathogens. Applying 6- to 12- percent dilutions of the bacterial compounds achieved 90 to 100 per cent suppression of Phytophthora cactorum lesions on leaves. P. cactorum can cause root, collar and crown rots, as well as foliar and fruit infections.

Applications for patents on these treatments have been submitted, and partners are being sought to develop the bacterial metabolites for commercial use.