水稻品种倒伏指数QTL分析

利用由98个株系组成的Nipponbare（粳）/ Kasalath（籼）∥Nipponbare 回交重组自交系群体，对水稻倒伏指数与株高、茎粗及单株生物量等性状进行了相关分析，并对水稻倒伏相关性状QTL进行了分子标记定位和遗传效应分析。结果表明，株高、茎粗、单株生物量3性状与倒伏指数的相关系数均达1%显著水平。利用基于性状-标记多元线性

Quantitative Trait Locus Analysis of Lodging Index in Rice(Oryza sativa L.)

Lodging is a common problem in rice production and it can reduce yield, rice quality and mechanical harvesting efficiency, thus rice production with lodging resistance varieties has been a main aspect of high-yield and excellent-qualities rice breeding. Culm traits, including plant height (PH), culm thickness (CT) and biomass per plant (BPP), have been the main targets for improvement of rice lodging resistance. In the paper, the relationships between plant height, culm thickness, biomass per plant and lodging index (LI) in rice were analyzed and quantitative trait locus analysis were conducted in Nanjing, by using ninety-eight backcross inbred lines (BILs) derived from a intersubspecific backcross of Nipponbare ( japonica ) /Kasalath( indica )//Nipponbare. The result showed that plant height, culm thickness and biomass per plant, which were significantly correlated with the lodging index, were the main factors that caused the rice lodging. By using multiple regression analysis approach with flanking markers, a total of twelve QTL were identified to be significant for the four traits and the number of QTL for each trait ranged from two to four. The phenotypic variation was explained by individual QTL ranged from 11% to 24% for three QTL of PH, 9%-14% for two QTL of BPP, 11%-25% for three QTL of CT and 10%-18% for four QTL of LI, respectively. The clustering distribution of QTL flanked by the marker R2414 and C86 on chromosome 1 for the traits of PH, BPP and LI, which could explain the significant correlations among these traits, suggested the chromosome segment of R2414-C86 was important for lodging resistance. The QTL of qLI -3, which exhibited improving lodging resistance was located between the marker interval of R1618-C595 on chromosome 3 and independent from the QTL of the above traits, and might be hopefully used in rice breeding for lodging resistance and middle-higher culm varieties with molecular assistant selection technology.