ARS | Publication request: INTERFERENCE BETWEEN RED RICE AND RICE IN A TWO-YEAR REPLACEMENT SERIES STUDY

Submitted to: Proceedings of Southern Weed Science Society
Publication Type: Abstract Only
Publication Acceptance Date: February 1, 2001
Publication Date: N/A

Technical Abstract: A study was conducted in the greenhouse in 1998 and 1999 to evaluate the growth response of rice cultivars Kaybonnet and PI 312777 when grown together with Katy red rice (presumed cross between rice and red rice) and LA3 red rice (from Louisiana). The planting proportions were 3:0, 2:1, 1:2, and 0:3 (rice:red rice). Plant heights and leaf areas were measured 28, 49, and 70 days after emergence (DAE), and dry weights of plant leaves stems, and roots were determined. Relative yield for each species at each mixture proportion was calculated. Leaf area index of Kaybonnet and PI312777 rice at 70 days after emergence decreased as their density in the mixture proportions decreased. Leaf area index of Kaybonnet was lower than that of PI 312777 at all planting mixture proportions. Heights of Kaybonnet and PI 312777 were not different when grown with KatyRR and LA3 until harvest (70 DAE). At 70 DAE, height of KatyRR was reduced when planted with PI 312777 at 2:1 rice:red rice proportions compared to that with other mixtures. LA3 was not affected by the rice cultivars and mixture proportions. Kaybonnet relative yield for dry weight of above ground parts was lower than that from KatyRR and LA3. In the PI 312777 and KatyRR mixture, the relative yield for dry weight of PI 312777 was comparable to that of KatyRR and LA3. These greenhouse results indicate that Kaybonnet was less competitive that PI 312777 against KatyRR and LA3 red rice ecotypes.