Location: Vegetable Research2011 Annual Report
1a. Objectives (from AD-416)
Develop sustainable management strategies to manage watermelon vine decline.
1b. Approach (from AD-416)
Using a combination of reflective plastic mulch, resistant pollinators, and pesticde sprays (oils and insecticides) to manage whitefly vector populations, thus resulting in management of SQVYV that causes watermelon vine decline.
3. Progress Report
This research relates to inhouse objective 2: Identify and develop improved resistance to diseases in cucurbits, and elucidate genetic variability in the cucumber downy mildew pathogen. Three trials (fall 2009, spring and fall 2010) were conducted at the Southwest Florida Research Center (SWFREC) station in Immokalee, FL, to determine the effect of Squash Vein Yellow Virus (SqVYV)-resistant pollenizers in slowing down watermelon vine decline (WVD) in seedless melon production. Results showed that the percentage of watermelon fruit with WVD symptoms was significantly less in plots with SqVYV-resistant pollenizers compared to the susceptible pollenizer check plots. Based on these three trials (fall 2009, spring and fall 2010) we selected one SqVYV-pollenizer for use in spring 2011 trials. We used larger plot size in 2011. Overall, results showed that the percentage of seedless watermelon fruit with WVD symptoms was significantly less (=0.0002) in plots with SqVYV-resistant pollenizer compared to the susceptible pollenizer plots. Application of oil or insecticides on SqVYV-resistant pollenizer plots did not significantly reduce the WVD on the seedless watermelon fruit compared to untreated SqVYV-resistant pollenizer plots. However, application of Admire followed by two sprays of spiromefesin significantly reduced WVD on the seedless watermelon in SqVYV-susceptible pollenizers plots. These experiments will be repeated in fall 2011. Disease progress and whitefly data from the spring trial in 2011 are being analyzed.