花生出仁率QTL分析及其与荚果大小的相关性

Quantitative Trait Locus Analysis for Shelling Percentage and Correlation between Shelling Percentage and Pod Size Related Traits in Arachis hypogaea

花生是重要的油料作物,成熟花生的出仁率不仅与花生的产油量相关,还与果壳厚度及脱壳难易程度相关,是花生遗传改良的重要性状。本研究以远杂9102×徐州68-4杂交后代衍生的重组自交系(RIL)的188个家系为材料,2013—2014年连续2年考察出仁率和荚果表型,发现有29份材料的出仁率稳定高于高值亲本远杂9102。出仁率与荚果长、荚果宽、荚果厚和百果重之间呈显著或极显著负相关。利用已构建的包含365个标记22个连锁群的遗传连锁图,采用Win QTLcart 2.5软件的复合区间作图法对出仁率进行QTL定位和效应估计,2年共检测到22个出仁率QTL,表型贡献率为2.75%~13.49%,其中2年重复检测到的区间有5个(AHGS0344–AGGS2438、AGGS0957–AHGA7048、AGGS0058–AHGA72558、AHTE0446–AHGA363492和AGGS0311–AGGS2287),分布在连锁群LG02、LG03和LG10上,表型贡献率为3.61%~13.49%。结合前期对该群体荚果大小QTL定位分析结果,有4个与出仁率相关的区间同时存在荚果大小QTL,其遗传效应均相反。在2年能检测到的出仁率QTL中,LG02上的区间AHGS0344–AGGS2438有与荚果长相关的QTL。在1年能检测到的出仁率QTL中,LG13上的区间AHTE0470–AGGS1233有与荚果长、百果重相关的QTL,LG06上的区间AGGS1363–AHGA24894有与荚果长相关的QTL,LG18上的区间AHTE0381–AGGS0100有与荚果宽、荚果厚相关的QTL。

Peanut is an important oil crops, and the shelling percentage of mature pods is correlated with not only peanut oil production but also shell thickness and the easiness of shelling. Therefore, shelling percentage is regarded as a major trait in peanut breeding. In this study, the shelling percentage and pod size related traits were evaluated in 2013 and 2014 using 188 recombinant inbred lines（RILs） derived from the cross between two Spanish-type peanut cultivars（Yuanza 9102 × Xuzhou 68-4）. Twenty-nine RILs were found in greater shelling percentage than the high-value parent ＂Yuanza 9102＂. The shelling percentage was negatively correlated with pod length（P 〈 0.01）, pod width（P 〈 0.01）, pod thickness（P 〈 0.01）, and 100-pod weight（P 〈 0.05）. Using the CIM model in Win QTLcart 2.5, 22 QTLs associated with shelling percentage were identified in the two environments with the phenotypic variation explained ranging from 2.75% to 13.49%. Among these QTLs, five marker intervals detected in both years, i.e. AHGS0344–AGGS2438, AGGS0957–AHGA7048, AGGS0058–AHGA72558, AHTE0446–AHGA363492, and AGGS0311–AGGS2287, were located on LG02, LG03, and LG10 with the phenotypic variation explained ranging from 3.61% to 13.49%. Four marker intervals for shelling percentage found in this study have been reported for pod size related traits with opposite genetic effect using the same population in the previous study. AHGS0344–AGGS2438 on LG02 was detected for shelling percentage in both years and also detected for pod length in the previous study. The other three intervals were only detected in one year and also associated with pod length and 100-pod weight（AHTE0470–AGGS1233 on LG13）, pod length（AGGS1363–AHGA24894 on LG06）, and pod width and pod thickness（AHTE0381–AGGS0100 on LG18）.