In 2018, OFRF provided a grant to Edmund Frost of Common Wealth Seed Growers to assess resistance to both bacterial wilt and cucurbit downy mildew among selected cucumber and muskmelon seedstocks.
Frost’s cucumber breeding lines showed good potential for resistance or tolerance to both diseases during these trials, and OFRF provided a second grant in 2019 to continue this promising research.
Cucurbit downy mildew and bacterial wilt not only limit organic cucumber production in the Eastern US, but also seriously impact conventional growers.
Downy mildew is caused by a fungus-like organism called an oomycete that overwinters in tropical and subtropical areas. The spores blow north on the wind each year, causing serious damage to cucumber and other cucurbit family foliage.
Bacterial wilt (BW) is a disease that is transmitted by cucumber beetles, an insect native to North America. The disease starts at the leaves and travels through vines, eventually destroying plants.
Frost has found that the levels of resistance vary significantly between varieties of cucumber. Selecting and screening for resistance has become an important element of his cucumber breeding work.
The project included a bacterial wilt trial, late-planted downy mildew-focused breeding trials for both pickler and slicer lines, and collaboration with both university and farmer researchers on downy mildew-focused variety trials.
Overall, the feedback from farmers participating in the 2019 trials was positive. Results are included in Frost’s final report, which is now available to view here: https://grants.ofrf.org/research/grants/development-and-assessment-bacterial-wilt-and-downy-mildew-resistant-cucumber
Since its founding in 1990, OFRF has awarded 355 grants to organic researchers and farmers, investing over US$ 3M. All OFRF-funded research must involve farmers or ranchers in project design and implementation, take place on certified organic land, and include strong education and outreach components.
