Location: Agroecosystems Management ResearchTitle: Effect of length of interval between cereal rye cover crop termination and corn planting on seedling root disease and corn growth
|ACHARYA, J - Iowa State University|
|ROBERTSON, A - Iowa State University|
|LENSSEN, A - Iowa State University|
|Moorman, Thomas - Tom|
Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 11/18/2015
Publication Date: 11/18/2015
Citation: Kaspar, T.C., Acharya, J., Robertson, A., Bakker, M.G., Lenssen, A., Moorman, T.B. 2015. Effect of length of interval between cereal rye cover crop termination and corn planting on seedling root disease and corn growth. In: Proceedings of ASA-CSSA-SSSA Annual Meeting, November 15-18, 2015, Minneapolis, Minnesota. Poster No. 502. Available: https://scisoc.confex.com/scisoc/2015am/webprogram/Paper92188.html.
Technical Abstract: Cereal rye cover crops terminated immediately before corn planting can sometimes reduce corn population, early growth, and yield. We hypothesized that cereal rye may act as a green bridge for corn pathogens and may increase corn seedling root disease. A field experiment was conducted over two years to determine whether the length of the interval between cereal rye termination and corn planting affected incidence of seedling root disease and reduced corn population, growth, and grain yield. A cereal rye cover crop was terminated 25, 14, 10, or 3 days before planting or 1 day after planting and was compared with corn without a rye cover crop preceding it. At seedling corn plants were evaluated for root infections, populations, and plant size. At maturity corn shoot dry weight, population, and yield were measured. Grain yield of the rye treatments terminated 3 days before corn planting (DBP) and 1 day after planting (DAP) were significantly less than the no cover crop treatment. Rye terminated 10, 14, or 25 DBP did not significantly reduce yield. The rye treatment terminated 1 DAP also had fewer plants and ears at harvest (Pr < 0.10). Early plant samples taken at 5th leaf stage showed that corn shoot height, dry shoot weight and radicle length were reduced (P <0.10) following rye compared to no rye. Radicle disease incidence, radicle disease severity, and Pythium incidence were greater (P <0.01), while the incidence of Fusarium recovered did not differ, in corn following rye compared to no rye. Radicle infection and Pythium incidence was reduced in treatments where rye was terminated 21, 14 and 10 DBP compared to 3 DBP, and 1 DAP. Longer time intervals between rye cover crop termination and corn planting reduced root infection and detrimental effects on corn growth.