Fungicide seed treatments for control of stand loss caused by seedling disease in hybrid rice, 2018

摘要

An experiment was established in a field of League-type soil (sand 3%, silt 32%, clay 65%, and organic matter 4%, and pH 5.5) at the Texas A&M AgriLife Research and Extension Center, Beaumont, TX. All plots were inoculated by mixing seeds with R. solani inoculum prepared in oat bran at a rate of 1.0 g per ft of row prior to planting. Plots consisted of seven 16-ft rows, spaced 7 in. between rows. Five fungicide seed treatments (see table) were arranged in a randomized complete block design with eightreplication Seeds of the hybrid variety RTRL 760 were treated with the fungicides or other chemicals prior to planting. Rice was drill seeded at 30 lb/A on 20 Apr. Plots received 50 lb N/A of urea (46-0-0, N-P-K) on 2 May and 150 lb N/A of urea prior topermanent flood on 3 ] May. A mixture of the herbicides Command (0.5 pt product/A) and Halomax 75 (1.0 oz product/A) was applied at planting for weed control. Irrigation followed local recommendations. The permanent flood was established on 31 May. On 4May, 14 days after planting (DAP), stand of seedlings was measured as the number of seedlings in the central row of plot and converted to stand per row foot. On 18 May (28 DAP), stand and aboveground fresh biomass of seedlings were measured. Stand was measured the same as described above. Aboveground fresh biomass weight was assessed by weighing five plants randomly selected and cut at the soil line from each plot. Rice was harvested using a plot combine on 20 Aug. Grain yield and moisture were determined, and rice yields were adjusted to 12% moisture content. Data was subjected to ANOVA using SAS version 9.4. Means were separated using Fisher's protected least significant difference test.