|Torbert, Henry - Allen|
Submitted to: Rice Technical Working Group Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 12/2/2013
Publication Date: 12/15/2014
Citation: Dou, F., Zhou, X., McClung, A., Storlien, J., Lang, Y., Torbert, A., Hons, F., Wards, B., Kresovich, S., and Wight, J.. 2014. Cover crop, soil amendments, and variety effects on organic rice production in Texas. Proc. 35th Rice Tech. Work. Group Meet., New Orleans, LA, p. 141. Feb. 18-21, 2014. CDROM. Interpretive Summary:
Technical Abstract: The major challenges in organic rice production include optimization of nutrient utilization, weed management, and variety selection. In this study, we tested the effects of two soil amendment products, two fertilizer rates, and three cover cropping systems (clover, ryegrass, and fallow) on organic rice production in Beaumont, TX. In 2011-12 winter cover crops were established successfully with full coverage. The amount of dry biomass harvested was 5,257 and 5,780 kg/ha for the clover and ryegrass covers, respectively. Fields were cultivated in the spring and drill seeded with two rice varieties, Presidio and Tesanai 2. Presidio is currently grown widely in Texas due to its superior grain quality and good grain yield. Tesanai 2 is a high yielding variety from China that is grown on limited acreage for the flour industry in the southern US. High weed pressure in the fallow plots resulted in very poor stands. Cover crops had a similar effect on rice grain yield, although there was a trend for higher grain yield under the ryegrass treatment than under the clover treatment. Compared to Presidio, Tesanai 2 had significantly higher grain yield and greater plant height suggesting it may be more competitive with weeds. Compared to the fallow control, the 168 kg N/ha and 235 kg N/ha soil amendment rates increased rice grain yields by 11%. There was no difference in rice grain yields between the two applied N rates, indicating that 168 kg N/ha was sufficient for organic rice production in terms of N supply following a cover crop. These results suggest that winter cover crops are effective in reducing weed pressure and enhancing soil nutritional properties thus improving economic returns in organic rice production.