Submitted to: Proceedings of Southern Weed Science Society
Publication Type: Abstract Only
Publication Acceptance Date: 1/28/2002
Publication Date: 7/1/2002
Citation: Gealy, D.R., Burgos, N.R., Estorninos, L.E. 2002. Biology and geographic distribution of red rice populations sampled from commercial dryers [abstract]. Proceedings of Southern Weed Science Society. 55:116. Interpretive Summary:
Technical Abstract: Red rice (Oryza sativa L.) is one of the most troublesome weeds of rice in the southern U.S., and Arkansas produces more than half of the rice in this region. In order to better understand the distribution and infestation levels of red rice throughout Arkansas, rough rice seed samples were obtained from grower seed lots that had been delivered to numerous dryers operated by commercial rice mills. Rice mills transferred all samples to central processing locations, which facilitated efficient collection of samples for these studies. Red rice infestation levels in ~30 counties were determined from commercial records or by sampling representative subgroups of the rice seed lots. Over several years of sampling, infestations levels in grower seed lots by county ranged from 0.01% to 2.9% red rice. Approximately 200 representative samples were selected from year 2000 seed lots and grown out from single seeds in a field nursery at Stuttgart in 2001. Statewide, 80% of red rice accessions were awnless strawhull and 20% were awned blackhull. Days to heading of individual lots ranged from 85 to 110 d. Heights ranged from 92 to 150 cm and leaf dimensions varied by more than 100%. Sampling red rice from commercial dryers proved to be a highly efficient and low input method of evaluating statewide infestation levels, locations, and biological characteristics of this complex weed.