Location: Physiology and Pathology of Tree Fruits ResearchTitle: Effects of crop rotation, anaerobic soil disinfestation and mustard seed meal on disease severity and organic strawberry production in California
|SHENNAN, CAROL - University Of California|
|MURAMOTO, JOJI - University Of California|
|BAIRD, GRAEME - University Of California|
|ZAVATTA, MAGHERITA - University Of California|
|NOBUA, BEATRICE - University Of California|
Submitted to: Symposium Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 9/9/2018
Publication Date: 9/9/2018
Citation: Shennan, C., Muramoto, J., Mazzola, M., Baird, G., Zavatta, M., Nobua, B. 2018. Effects of crop rotation, anaerobic soil disinfestation and mustard seed meal on disease severity and organic strawberry production in California. Symposium Proceedings. p. 11.
Technical Abstract: We report on the first six years of an experiment comparing two and four - year crop rotations, with either lettuce or broccoli as the main rotation crop between strawberries. Strawberries were planted every other year in rotation with lettuce or broccoli (2yr), and every fourth year (4yr) in rotation with either broccoli–lettuce/cauliflower–broccoli (br) or lettuce-broccoli-lettuce (let). Each rotation included four fertility/ disease management systems: 1) bare winter fallow + strawberry with fertigation (bf); 2) winter legume/cereal cover crop before vegetables and anaerobic soil disinfestation (ASD) prior to strawberry planting and fertigation (cc); 3) same as for cc except that supplemental compost was added annually, and organic fertilizer added as needed to vegetable crops based on a pre-sidedress nitrate test (cc+c+f); and 4) same as cc except a cereal rye cover crop was used and mustard seed meal added as an amendment at cover crop incorporation and prior to strawberry planting (msm). Strawberry yields and severity of wilt systems were monitored for each crop, and in year 6 (2017) pathogen levels in strawberry crowns were assessed using real-time quantitative PCR. In all three years when strawberries were grown, yields were negatively related to severity of wilt symptoms, and in year 4 (all rotations) and year 6 (2yr only) yields were higher in the br than the let rotations. In year 4 a positive effect of ASD was found in 2yr but not in 4yr treatments. The main pathogen present was Verticillium dahliae, which was partially controlled by br rotation and ASD alone and in combination. Lowest yields were seen in the bf and msm treatments in let rotations.