Corn Gluten Meal as an Alternative Weed Control Option for Spring-Transplanted Onions

Abstract Successful screening of suitable onion (Allium cepa L.) varieties, viable production areas, and potential marketing options suggest that onions are a potential alternative crop for Oklahoma and northeast Texas. Unfortunately, onion's slow growth rate, short height, non-branching plant structure, low leaf area, and shallow root system can result in a total loss of marketable yields as a result of weed competition. Field research was conducted in 2002 and 2003 in southeast Oklahoma (Lane, OK) to determine the weed control efficacy of selected preemergent synthetic herbicides and corn gluten meal (CGM) for use in spring-transplanted onion cv. Hybrid Yellow Granex PRR, production. There were 21 treatments [12 synthetic herbicide treatments, 5 CGM application rates, a full-season weed-free (hand-weeded) treatment, a full-season weedy-check, a partial-season weed-free (weed-free for the first half of the growing season), and a weedy-check without onions]. Weed cover and weed control ratings were collec...