|Henry, Chris - University Of Arkansas|
|Anders, Merle - University Of Arkansas|
Submitted to: Rice Technical Working Group Meeting Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 12/2/2013
Publication Date: 12/15/2014
Citation: Teaster, N.D., Henry, C.G., Anders, M.M. and McClung, A.M. 2014. A genetic approach to producing rice using less irrigation water. Proc. 35th Rice Tech. Work. Group Meet., New Orleans, LA, p. 70. Feb. 18-21, 2014. CDROM.
Technical Abstract: Research has shown that conventional rice production using the permanent flooded system can also result in high methane emissions, increased grain arsenic accumulation, and extensive demand on irrigation resources. Although rice is a staple grain for feeding half the world, there has been increasing interest in developing sustainable rice production systems that have less negative impact on the environment. Producing rice using aerobic culture or intermittent flooding practices has been adopted in various parts of the world and, to a limited extent, in the USA as a means of reducing irrigation costs. This study was initiated to identify genomic-trait relationships for plant characteristics that are important for rice production using intermittent flood culture. A chromosome segment substitution line (CSSL) population derived from a backcrossing TeQing, an indica cultivar from China, into the recurrent parent, Lemont, a japonica cultivar from the USA, was used. The population was previously genotyped using 178 Simple Sequence Repeat (SSR) markers and possesses one marker every 0.5 cM, on average. The genetic materials consisted of 117 introgression lines, the two parents, and 32 cultivars that serve as parentals for several other mapping populations. The study was conducted in Stuttgart, AR during 2013 and included two irrigation methods, permanent and intermittent flood, and four replications. Each genotype was represented by about 7 hill plots per replication and two representative plants were selected for phenotyping. Traits that were measured included: days to heading, plant height, plant type, tiller number, panicle length, number of panicles, number of seeds per panicle, total kernel weight per panicle, 1000 grain weight, and total grain yield per plant. Soil moisture was mapped to track water stress levels in the intermittently flooded plots. Rainfall and other weather conditions were recorded on site to determine their effect on soil moisture and water stress. Initial analysis of population plant growth data by irrigation treatment revealed significant differences for intermittent flooding relative to permanent flooding; decreased plant height, increased days to heading, but no change in plant type. Additional results for other agronomic traits will be presented as well as plans for quantitative trait loci analysis (QTL). This study will generate phenotypic information which will be used to associate traits with genetic markers that can ultimately be used for the selection of cultivars with economically sustainable crop yields under reduced irrigation use.