vegetable production

OEFFA's 2020 conference is Feb 13-15 in Dayton, Ohio

It's time again for Ohio's largest sustainable food and farm conference. This year's OEFFA Conference will feature a larger trade show area, plus three days of workshop sessions and events featuring more than 70 topics and speakers. 

Among this year's educational sessions, the Ohio State Vegetable Production Systems Lab will host Do's and Don'ts of Getting More From Microbe-Containing Crop Biostimulants on Friday, February 14 from 12:45-1:45pm. Session leader Matt Kleinhenz invites producers to bring along their lunch and share experiences, concerns, and questions about these commonly used, but often difficult to evaluate, products.

Kleinhenz, an Extension specialist and professor with The Ohio State University’s Department of Horticulture and Crop Science, will lead discussion on the promise and challenge of using microbe-containing crop biostimulants in organic crop production, with an emphasis on vegetable production.

While many organic growers use these types of inputs, the benefits of doing so are rarely clear. Kleinhenz will discuss major reasons for these unclear responses. He will also provide tips for selecting, using, and evaluating biostimulant products effectively. The workshop will integrate hands-on demonstrations and how-to discussions, incorporating news from farms, research stations, and product manufacturers. Participant questions and observations will be blended into discussion on product-crop and product-product compatibility, preparation, application, handling, storage, and normal product effects on crops and yields. 

Kleinhenz and his lab have been working with microbe-containing biostimulants for several years, supported by the National Institute of Food and Agriculture USDA Organic Transitions Program and through the North Central Region SARE program. Those unable to attend the OEFFA conference session can read more about Ohio State work with Microbial-based Biostimulants (MBBS) and their Use in Commercial Vegetable Production by visiting the Vegetable Production Systems Laboratory website: https://u.osu.edu/vegprolab/research-areas/vegebiostimsferts/ 

Kleinhenz is one of 17 Ohio State presenters at this year's OEFFA conference. For more details about the OEFFA conference and schedule, visit www.oeffa.org/conference2020.php. Walk-in registration is available for Friday and Saturday's programming. The Exhibit Hall is open to the public on Thursday from 4:00-7:00 p.m. and Friday from 5:00-6:30. p.m. 

Based on an article from Organic Seed Alliance by Kiki Hubbard. Read the full article here

New varieties of disease-resistant cucurbits are commercially available as a result of Cornell University's Eastern Sustainable Organic Cucurbit Project. 

Through participatory efforts with farmers and regional seed companies, Extension researchers developed new varieties with organic producers in mind, focusing on resistance to common diseases and pests, but also on production and culinary characteristics important to organic farmers. 

“All of our successes with DMR are owed to farmer input,” says project director Michael Mazourek. “We took moderately resistant material that we had at Cornell, moderately resistant material identified by organic farmers, and people are seeing the literal cross-pollination of these partnerships in DMR varieties now available to growers.”

‘Trifecta’ muskmelon stood out for its excellent eating quality and yield–even under levels of downy mildew pressure that defoliated most commercial melon varieties. The variety also exhibited good bacterial wilt resistance and was less prone to damage from striped cucumber beetles. ‘Trifecta’ is currently available for sale through Common Wealth Seed Growers and Southern Exposure Seed Exchange.

DMR401 cucumber, a downy-mildew resistant (DMR) slicing cucumber variety, now available for purchase through Common Wealth Seed GrowersHigh Mowing Organic SeedsSeedWise, and Southern Exposure Seed Exchange.

DMR264 cucumber, excellent resistance to new strain of downy mildew, smaller and bred for warmer climates with severe pressure from downy mildew. Available from Common Wealth Seed Growers.

Additional varieties are being tested for release.

The Eastern Sustainable Organic Cucurbit Project has received funding from the USDA Organic Research and Extension Initiative, as well as the Organic Farming Research Foundation, Sustainable Agriculture Research and Education (SARE), and the Clif Bar Family Foundation. Read more about the project at eOrganic.

tomato in test plot

Use of compost and a mixed species hay crop are recommended.

For farmers transitioning from a conventional to an organic farming system, decisions made during the three-year transition period can influence important factors of future production, such as soil-borne pathogens, soil fertility, and soil structure. In this study, compost incorporation strongly affected physical, chemical, and biological soil health factors and, overall, the soil food web. Using a mix of perennial hay during the transition was most successful in reducing disease-causing pathogens in the soil. Highest available N and yields occurred in the plots using high tunnel vegetable production.

Materials and Methods

A three-year study was conducted in Wooster, Ohio, to evaluate four common rotational strategies used during transition from a conventional to an organic farming system. The four organic transition strategies evaluated were: 1) tilled fallow, 2) a single planting of mixed species perennial hay, 3) low intensity open field vegetable production, and 4) intensive vegetable production under a high tunnel.

Each transition strategy plot was split in half with 15,000 lbs./ac composted manure applied each year to one half.

At the year of certification, the fields were planted to tomato, with two smaller plots of soybean.

Key Findings

  • Compost treatment increased organic matter of soils in all treatments, lowered bulk density, and increased NO3-N, and microbial biomass-N.
  • The addition of compost boosted plant vigor for tomatoes for all transition strategies, but had an inconsistent effect on suppression of soil-borne diseases.
  • Transition cropping strategy was the main factor influencing bacterial community structure in the soil and the rhizosphere.
  • Bacterial communities involved in disease suppression were more abundant in soil previously cropped with hay compared to tilled fallow and low-intensity vegetable production. This was true for both tomato and soybean crops.
  • Overall, the mixed hay was the most effective in decreasing damping-off for both tomato and soybean crops.
  • Tomato yield during year four was much higher in the high tunnel plot. The hay treatment also showed better yield than the tilled fallow and open field vegetable production.

Why Researchers Think the Hay and High Tunnel Treatments Did Better

Disease suppression might happen in two ways. One involves specific action against pathogen populations. For example, brassicas (cauliflower, kale, turnip, radish, cabbage) suppress soil-borne diseases by exuding sulfur-rich substances that are toxic to many pathogenic soil organisms. And certain species of nematodes eat bacteria and fungi that cause plant diseases. Disease suppression can also occur from high competition for available resources. In both cases, the disease suppression is associated with the overall composition of the microbial community (bacteria, fungi) present in the soil and the rhizosphere.

The hay crop used in this experiment was a combination of Festulolium (a rye fescue hybrid) under-sown with alfalfa, red and white clover, timothy, chicory, orchardgrass, and plantain in equal proportions. Researchers concluded that the above-ground diversity of the hay mix supported an increase in beneficial soil organisms that compete or interfere with pathogens, thus, reducing incidence of disease in future crops.

The highest yields in this study were from the high tunnel plots. While some of the increase resulted from extending the growing season, soil analyses also found a higher level of available N in the high tunnel plots. Researchers think this was a result of maintaining the soil food web in a biologically-active state during the cold early spring months in northern Ohio. The monthly mean soil temperature inside the high tunnels was warmer by 35–41°C from January to May while from July to September it was marginally lower than the outside soil temperature. (Based on top 4 inches.)

For more information on using tunnels in vegetable production, visit the Vegetable Production Systems Laboratory’s Crop Enivronments page.


Prepared by Louceline Fleuridor and Cassandra Brown

Based on summaries of the following papers:

Benítez, MS; Baysal, F.; Rotenberg, D.; Kleinhenz, M.D.; Cardina, J.; Stinner, D.; Miller, S.A.; Gardner, B. B. 2007. Multiple statistical approaches of community fingerprint data reveal bacterial populations associated with general disease suppression arising from the application of different organic field management strategiesSoil Biology and Biochemistry Volume 39, Issue 9, September 2007, Pages 2289-2301

Briar, S.S., Miller, S.A., Stinner, D., Kleinhenz, M.D., & Grewal, P.S. 2011. Effect of different organic transition strategies for peri-urban vegetable production on soil properties, nematode community, and tomato yield. Applied Soil Ecology, 47, pgs 84-91.

Baysal, F; Benitez, MS; Kleinhenz, MD; Miller S.A.; Gardner B.B. 2008. Field management effects on damping-off and early season vigor of crops in a transitional organic cropping system. Phytopathology, Vol. 98, No. 5.