Submitted to: Journal of the National Association County Agricultural Agents
Publication Type: Peer reviewed journal
Publication Acceptance Date: 5/13/2014
Publication Date: 6/4/2014
Citation: Wertheim, F.S., Douds, D.D., Handley, D.T., Hutton, M. 2014. Evaluating the potential of mycorrhizal fungi to boost yields in field grown leeks. Journal of the National Association County Agricultural Agents. http://www.nacaa.com/journal/index.php?jid=281. Interpretive Summary: Arbuscular mycorrhizal fungi are naturally-occurring soil fungi that form a symbiosis with most crop plants. The symbiosis helps plants take up nutrients from the soil, resist drought, and resist diseases. These potential benefits make utilization of mycorrhizal fungi particularly attractive in organic agriculture. Inocula of these fungi are now available commercially and through a recently developed method in which farmers can produce it themselves on-farm. We utilized two brands of commercially available mycorrhizal fungus inoculum as well as inoculum produced on-farm to test their effects on the growth of leeks at two organic farms in Maine during 2010 and 2011. Our results showed one commercial inoculum was ineffective both years, one significantly enhanced growth one year, and the on-farm produced inoculum did well both years. Mycorrhizal fungus inocula have great potential use on organic farms in Maine.
Technical Abstract: UMaine Cooperative Extension faculty collaborated with a local organic grower and the USDA-ARS Research Center in Wyndmoor, PA to evaluate the potential of mycorrhizal fungi to boost yields in field grown leeks using both commercially available mycorrhizal inocula and a “farm raised” mycorrhizal inocula. The farm raised inoculum was produced using a technique developed at the Wyndmoor, PA research facility. Both the farm raised and the commercial mycorrhizal fungi inocula treatments were compared to a control treatment using no mycorrhizal inocula. The study was conducted at the Highmoor Farm Experimental Horticultural Research Station in Monmouth, Maine and at Wolf Pine Farm, an organic CSA Farm located in Alfred, Maine. Leeks were chosen for this study for their low pest profile, market value, and ease of harvest and data collection. Data collected in the 2010 leek study at both farm sites indicated that the leeks treated with the “farm raised” mycorrhizal inocula yielded more than 20 percent higher by weight than the control, uninoculated leeks. Yields from the leeks treated with the commercial inocula did not yield significantly different from the control. In 2011 leeks treated with farm raised inocula yielded 12% higher though the result was not statistically significant. Of the two commercial inoculum used, MycoApply yielded 30 % higher and MycoGrow was no different from the control.