Posted: May 23, 2017

A proposal by Drs. Jiménez Gasco and Peter receive program support for fruit production research funds, effective July 1.

Effective July 1, Associate Professor Dr. María del Mar Jiménez Gasco and Assistant Professor Dr. Kari Peter will receive Stoy G. and Della A. Sunday Program Support for Fruit Production Research funds for their proposal titled "Impact of antibiotics in agroecosystems: exploring the effect of oxytetracycline on peach bacterial epiphytic communities."

Bacterial leaf spot of stone fruits is the most limiting factor in peach production in PA. The disease, caused by the bacterial pathogen Xanthomonas arboricola pv. pruni is primarily managed by the intensive use of the antibiotic oxytetracycline. Although there is increasing interest in organic production, a majority of PA peach growers use conventional production methods, plant consumer‐preferred peach cultivars that are highly susceptible to the disease, and have no other management alternative to control Bacterial leaf spot other than oxytetracycline. At the same time, antibiotic use reduces the diversity of epiphytic bacteria that compete for niche and infection sites with the pathogen, leaving an open way for infection and disease.

The specific objective of this research is to study changes in the epiphytic bacterial community in peach orchards using management practices used in organic production.

A long‐term goal of Drs. Jiménez Gasco and Peter is to understand how resistance to oxytetracycline occurs, so they can design better practices to manage bacterial leaf spot that do not lead to the development of resistance in X. arboricola pv. pruni populations. They are also looking for alternatives to antibiotics from practices used in organic production (lime sulfur, copper, biocontrol agents, and plant growth promoters) that can control bacterial leaf spot but do not affect the population number and diversity of epiphytic bacteria.

Contact Information

María del Mar Jiménez Gasco, Ph.D.
  • Interim Department Head, Plant Pathology and Environmental Microbiology;