Submitted to: Plant Disease Management Reports
Publication Type: Other
Publication Acceptance Date: December 6, 2010
Publication Date: March 28, 2011
Citation: Zhou, X., McClung, A.M., Cammack, J.L. 2011. Responses of rice cultivars and elite lines to diseases in no-till organic production system, 2010. Plant Disease Management Reports. 5:FC093. Technical Abstract: The experiment was established in a field of League-type soil (3% sand, 32% silt, and 64% clay) under organic management for many years at the Texas A&M University System's Agrilife Research and Extension Center, Beaumont. Twenty rice cultivars and lines were arranged in a randomized complete block design with four replications. Plots consisted of six 15-ft rows, and spaced 7 inches between rows. Durana white clove (6 lb/A) was planted on 4 Nov, 2009, and flail mowed on 28 Apr, 2010. Rice was no-till seeded at 100 lb/A over mowed clover on 29 Apr. Plots received 1000 lb/A of organic Nature Safe fertilizer (13-0-0, N-P-K) on 30 Apr. Plots were flushed on 3 and 5 May. Permanent flood was established on 24 May. Plots were irrigated as locally recommended. On 8 Aug, severity of straighthead, narrow brown leaf spot, bacterial panicle blight, brown spot, and leaf smut were rated on a scale of 0 to 9, where 0 represents no symptoms and 9 represents most severe. All diseases resulted from natural inoculum. Plots were harvested at the maturity stage of individual cultivars and lines, and grain yield adjusted to 12% grain moisture. Due to high levels of organic residue in no-tilled soil, straighthead occurred in all cultivars and lines with Cocodrie and its derived lines RU0703144 and RU0703190 having the most severe symptoms. Narrow brown leaf spot was most severe on Cocodrie, Cybonnet, Jazzman, Presidio, RU0703190, and Sierra. All other varieties and lines had little or low levels of narrow brown leaf spot. Bacterial panicle blight occurred on several cultivars including Bengal and MCRO2-1572. Brown spot was commonly present on all cultivars and lines with no statistically significant differences among them. Leaf smut was minor in general for all cultivars and lines. Tesanai 2, GP2 and Jasmine 85 had highest yield.