Project Number: 1931-22000-009-00
Project Type: Appropriated

Start Date: Mar 20, 2012
End Date: Mar 19, 2017

Objective:
1: Develop effective biologically based systems for managing postharvest disease of temperate fruit crops. 1.A. Establish a biocontrol system to control brown rot of stone fruits. 1.B. Determine the cytological aspects of resistance in wild apple fruit from Kazakhstan to blue mold. 1.C. Develop a biocontrol management system for gray mold and anthracnose of strawberry high-tunnel production utilizing UV-C and microbial antagonists. 2: Develop knowledge base on the biology of postharvest biocontrol systems for use in selecting superior antagonists and to improve the overall efficacy of biocontrol agents. 2.A. Determine the effect of yeast induced reactive oxygen species (ROS) on host resistance. 2.B. Determine mechanisms associated with biocontrol of brown rot of stone fruits.

Approach:
Research is focused on reducing the need of using postharvest fungicides in fruit production. It includes developing postharvest biological control of brown rot latent infections of stone fruits, basic studies on biocontrol systems, explaining the cytological basis for the resistance of Malus sieversii (‘Kazak’) apples to blue mold, and using LED lights to reduce gray mold and anthracnose of strawberries in high tunnel cultures. The seasonality of fruit availability allows the project to address the different objectives. Biocontrol studies on stone fruits will be conducted in early summer, resistance research on Kazak apples in the fall, and biocontrol studies on strawberry during the winter. Biocontrol of latent infections will include scale-up tests under simulated commercial conditions and research explaining the mechanism of biocontrol. Resistance studies of ‘Kazak’ apples will focus on characterizing the biochemistry of wound responses. Strawberry research will involve determining the effect of different UV-LED wavelengths on survival of B. cinerea and Colletotrichum spp., and epiphytic microflora, its effect on plants, and the use of selected LED in combination with antagonists to reduce gray mold and anthracnose. Basic research on yeast-based biocontrol systems will determine the effect of reactive oxygen species (ROS) on the efficacy of yeast antagonists and the ability of yeast ROS to induce defense systems in apple. This research will give growers alternative biological tools to combat fruit diseases, improve the efficacy of biocontrol systems, and in the case of the Kazak work, provide new information for the basis of postharvest disease resistance in apple germplasm that can be used in breeding programs.