Study On Application Of The Rice Photo-Thermo-Sensitive Genic Male Sterile Line, Kes

KE S, a two-line hybrid rice based on thermo-photo-sensitive genie male sterile (PTGMS), was investigated in this study. The botanical morphology, such as main agronomic characteristics and outcrossing traits, was investigated through continuous interval seeding at two sites, Changsha and Sanya. Contrasted with Y58S and P88S, two most popular PTGMS in China, we recorded and analyzed self seed setting rate and the pollen fertility rate of KE S under natural conditions at two sites, and conditional cool-pool at Changsha. Additionally, we planted24hybrid varieties of rice in Changsha, which are crossed by three female parents KE S, Y58S and P88S with8male parents, and observed their agronomic traits, furthermore, analyzed their combining ability and ultimately got new competitive hybridized combinations. The results of this study listed as follows show that the KE S is a safe and valuable fertile line:1) Investigation results of agronomic traits of KE S:In Changsha site, the mean of duration from seeding to heading is75.6±7.0days, plant height71.0±3.7cm, mean number of efficient panicle per plant is12.2±1.6, mean number of spikelet per panicle is139.0±11.4; in Sanya site, the corresponding data are separately listed as80.1±8.1days,71.2±3.7cm,12.7±1.9,133.1±11.4;2) Investigation results of outcrossing traits of KE S:In Changsha site the florescence in a panicle concentrated in the3th-5th day accounting to69.43%, the flowering spikelet’s accounting to83.6%. The clasping spikelet rate is9.87%and the total stigma exerted rate86.05%; In Sanya site the florescence in a panicle concentrated in the3th-5th day accounting to73.71%, the flowering spikelets accounting to84.6%. The clasping spikelet rate is4.62%and the total exerted rate89.86%;3) The results identified in conditional cool-pool showed that the CTP (critical point temperature) of fertility alteration in KE S, Y58S and P88S separately is below22℃, below22℃and above23.5℃;4) Both GCA (general combining ability) and SCA (specific combining ability) were remarkable at5%or1%levels for24hybridized combinations in8main traits, of which the grain yield per plant mainly affected by GCA of male parents;5) Several competitive probable hybridized combinations were selected, whose female parents are KE S, therefore, they will be indentified in resistance, rice grain quality etc. and ultimately we get the most competitive combinations.