Watermelon is a major cucurbit crop grown on over 100,000 acres and valued at more than $500 million annually. A significant portion of the watermelon crop is grown in the eastern United States where Phytophthora fruit rot occurs regularly resulting in severe yield losses. CucCAP researchers in Charleston, SC developed 5 Phytophthora fruit rot resistant watermelon germplasm lines with high levels of resistance against a broad range of diverse P. capsici (20) isolates collected from across the United States. These resistant germplasm lines are being used in breeding programs to develop resistant cultivars.
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Phytophthora fruit rot susceptible cultivar Sugar Baby (fruit on left) compared with resistant germplasm line USVL203-PFR (fruit on right). Intense sporulation and growth of the fruit rot pathogen Phytophthora capsici is observed on susceptible cultivar Sugar Baby, whereas no sporulation is seen on USVL203-PFR.
For more reading:
- Broad resistance to post-harvest fruit rot in USVL watermelon germplasm lines to isolates of Phytophthora capsici from across USA.
by: Chandrasekar S. Kousik, Jennifer Lauren Ikerd, William Wechter, Sandra Branham, and William W. Turechek
Published online by Plant Disease on September 27, 2021.
DOI: 10.1094/PDIS-11-20-2480-RE