Increasing sustainable grain and oilseed production is a significant challenge for US producers. Double-cropping soybean [Gly-cine max (L). Merr.] with a winter annual crop is one option to increase grain and oilseed production while reducing nutrient and sediment losses. Anecdotal observations that winter wheat (Triticum aestivum L.) limits double-crop soybean productivity are common, which is seemingly corroborated by documentation that winter wheat contains allelopathic compounds. Despite these observations and documented evidence, the winter wheat double-crop soybean system is prevalent in the mid-South. Investigations are lacking that document physiological differences in soybean plants when preceded by different winter annual crops. This study examined the effect of four winter annual treatments (wheat, canola [Brassica napus L.], barley [Hordeum vulgare L.], and a fallow, non-planted control) on soybean germination in the laboratory, seedling growth in a greenhouse, and harvest population and grain yield in field experiments at Princeton, KY, from 2014 to 2016. The only consistent finding was detected for seedling growth; soybean roots were shorter and lighter 1 mo after planting when grown in field-collected soil cores from wheat or barley crops. Differences were not detected for seed germination or seed yield. Based on results of this study and previously unpublished reports, it is possible that the anecdotal differences reported among winter annual crops may be due to an interaction between reduced root growth and environmental conditions, such as limited water or nutrient availability.
|Number of pages||9|
|State||Published - Jul 1 2018|
Bibliographical noteFunding Information:
Financial support for this research was provided by the Kentucky Soybean Promotion Board. This publication was is in partial fulfillment of the requirements to obtain a Master of Science degree and approved for publication by the Director of the Kentucky Agricultural Experiment Station. The authors thank the following for their contributions: John James, Ethan Snyder, Katherine McLachlan, Robbie Anderson, and Kirsten Banks for their tireless assistance in the field, greenhouse, and laboratory; and Sara Janse for her statistical expertise and contributions.
© 2018 by the American Society of Agronomy.
ASJC Scopus subject areas
- Agronomy and Crop Science