Project Number: 6659-22000-024-00
Project Type: Appropriated

Start Date: Apr 04, 2011
End Date: Mar 31, 2016

Objective:
1. Identify and characterize host plant resistance and facilitate incorporation of resistance factors into advanced breeding lines of watermelon (for sweetpotato whitefly) and sweetpotato (for the complex of soil-borne insects including but not limited to wireworms, flea beetles, cucumber beetles, white grubs, and sweetpotato weevils): 1.A Characterize watermelon germplasm lines with resistance to the sweetpotato whitefly and incorporate resistance factors into advanced watermelon breeding lines; 1.B. Identify and characterize sweetpotato clones with resistance to soil insect pests and use a recurrent mass selection breeding approach to generate clones with high levels of resistance and good horticultural characteristics. 2. Assess the importance and utility of biological control agents for the management of insect pests of cucurbits to include sweetpotato whitefly using predators and parasitoids, and for pickleworms using nucleopolyhedroviruses (NPV). 2.A. Develop NPVs for management of pickleworms and other pests of cucurbits; 2.B. Assess the effect of mixed plantings of cucurbits with other vegetables and plant species on the population abundance and behavior of predators and parasitoids for the management of the sweetpotato whitefly. 3. Identify whitefly-host plant-virus relationships and develop methods for protection from the whitefly-vectored viruses of vegetables such as sweetpotato and watermelon.

Approach:
Conduct greenhouse and field trials to identify sources of resistance and evaluate genetic populations to determine heritability of resistance against sweetpotato whiteflies in melon and watermelon, and against soil insect pests of sweetpotatoes; cross appropriate germplasm to facilitate incorporation of resistance into advanced sweetpotato breeding lines and new cultivars; evaluate chemical and physical mechanisms of resistance in sweetpotato to soil insect pests; investigate the influence of resource plants on predators and parasitoids of whiteflies in cage and field trials; assess the usefulness of baculoviruses for control of pickleworms and other cucurbit pests; study the epidemiology of sweet potato leaf curl virus in sweetpotato; and survey the presence and epidemiology of whitefly-transmitted viruses of cucurbits.