Qtl For Traits Related With Potassium Deficiency Resistance In Rice

Potassium, one of the essential macronutrients for rice growth, exists almost entirely in cationicform and plays a very important role in many physiological processes. About1/4to1/3of the arablesoils in China are considered K deficient, K deficient stress can limit rice growth and reduce yields. Tosolve this problem, the most effective way is to develop new varieties with a high level of K deficienttolerance. In the present study, the population used contained194RILs is derived from a cross between“R9308” and “Xieqingzao B”. Using the method of hydroponic culture, set three K conditions：lowK(LK), moderate K(MK) and control K(CK), and two relative conditions low K compared with controlK and moderate K compared with control K, at the seedling stage, map and analyze QTL for traitsrelated to K deficient tolerance. The main results are as follows:1. In2010,86QTL for thirteen traits were located under three K conditions, the main QTL containqRMgC-11a,qSMgC-4a,qSMgC-4b, qSMgC-4c and qSNaC-7b, individual QTL explained13.95%,14.16%,26.27%,28.57%,17.12%of the phenotypic variance, respectively;22QTL for thirteen relativetraits were located under two relative K conditions, the main QTL contain qRSNaC-7explaining13.66%of the phenotypic variance。2. In2011,71QTL for thirteen traits were located under three K conditions, the main QTL containqPH-3d, qRMgC-11a, qRMgC-11b, qSMgC-4b, qSMgC-4c, individual QTL explained16.66%,27.23%,13.40%,16.56%,10.35%of the phenotypic variance, respectively;22QTL for thirteen relative traitswere located under two relative K conditions, the main QTL contain qRRMgC-11a, qRRNaC-11,individual QTL explained17.46%,14.63%of the phenotypic variance, respectively.3. The QTL detected in two years: QTL for root K+concentration mapped within the intervalsRM7454—RM82, RM351—RM234on chromosome7, respectively; QTL for root Mg2+concentrationmapped within the intervals RM263—RM3512, RM271—RM3773, RM3428—RM53492,10,11,respectively; QTL for shoot K+concentration mapped within the intervals RM32—RM5485,RM3428—RM5349on chromosome8,11, respectively; QTL for shoot Mg2+concentration mappedwithin the intervals RM7192—RM488, RM5757—RM273on chromosome1,4, respectively; QTL forshoot Na+concentration mapped within the intervals RM7454—RM82, RM351—RM234onchromosome7, respectively.These QTL were expressed steadily and not fluenced by environment, theQTL for on shoot Mg2+concentration on chromosome4and the QTL for root Mg2+concentration onchromosome11as main QTL need further analysis, including the fine mapping and cloning, which mayuse in molecular marker assisted breeding.