不同生长环境下水稻氮、磷、钾利用相关性状的QTL定位分析

【目的】鉴定影响水稻氮、磷、钾利用相关性状的QTL,为开展水稻养分高效利用分子标记辅助选择育种和肥高效基因的图位克隆提供依据。【方法】以云南强耐冷(2级)粳稻地方品种丽江新团黑谷与十和田杂交、回交获包含105个株系的孕穗期耐冷性近等基因系BC4F8及双亲为材料,在云南白邑(冷水胁迫)、寻甸(自然低温胁迫)和玉溪(正常生长环境)3种生长环境下进行水稻氮、磷、钾养分吸收相关性状的鉴定,并利用构建的含有180个SSR标记,全长为1820.6 c M,标记间平均距离为15.67 c M的遗传图谱,用基于完备区间作图法的QTL Ici Mapping V3.2软件对16个性状进行QTL定位分析。【结果】3种环境下共检测到56个QTL,分布在第1、2、3、4、5、6、7、9和10染色体上,单个性状QTL数为1~10个,单个QTL可解释的各自性状表型贡献率为8.88%~35.30%。其中,氮、磷、钾利用效率QTLs数分别为12个、27个和17个。而q TNA-1a、q TPA-1、q PHI-1、q PHI-6、q PHI-7b和q KHI-6共6个QTL在冷害和正常环境下均能检测到,稳定性较高,其贡献率变幅为10.63%~31.57%。在第1、3、4、5、6、7和10染色体上有13个标记区域存在QTL成族分布,单个QTL位点控制的性状数为2~5个,其中共同控制磷总吸收量、磷素干物质生产效率、磷素收获指数、每100 kg籽粒需钾量和钾素收获指数等性状的位点数最多。【结论】获得56个影响氮、磷、钾利用相关性状的QTL,且发现的13个QTL富集区可作为水稻氮、磷、钾高效利用分子育种的重要候选区域。

Identification of QTL traits on N,P and K utilization in rice under different growth environments

【Objectives】To provide the basis for the breeding program of molecular assistant selection (MAS) and map-based cloning of high nutrition efficiency utilization, the traits of quantitative trait locus (QTLs) on nitrogen, phosphorus and potassium utilization in rice were identified. 【Methods】 A set of 105 near-isogenic lines, BC4F8 population was developed by backcrossing between Lijiangxintuanheigu (the stongly cold-tolerant japonica landrace, grant No.2) as a donor parent and Towada (cold-sensitive japonica cultivar) as a recurrent parent, and was used as materials, and were planted in Baiyi (cold water irrigation), Xundian (natural low temperature condition) and Yuxi (normal growing environment) in Yunnan, respectively. Sixteen traits associated with N, P, K utilization were evaluated under three different ecological environments. The phenotypic data of 105 NILs, genetic map containing 180 microsatellite markers with 1820.6 cM of the genome, and 15.67 cM average distance between the markers were used to analyze QTLs of N, P and K utilization in rice by the statistic software of QTL IciMapping V 3.2. 【Results】 The total 56 QTLs were detected under three different environment, and were confirmed to be distributed on chromosome 1, 2, 3, 4, 5, 6, 7, 9, and 10, respectively. The number of QTL for single trait was varied from 1 to 10, and the single QTL accounted for 8.88%-35.30% of the phenotypic variation. N, P and K utilization efficiency of No.12, 27, and 17 QTLs were respectively detected. Six QTLs, qTNA-1a, qTPA-1, qPHI-1, qPHI-6, qPHI-7b, and qKHI-6 were detected under cold stress and normal condition, and had high stability and explained 10.63%-31.57% of the phenotypic variation. Moreover, QTLs showed the cluster distribution in 13 QTL regions of chromosome 1, 3, 4, 5, 6, 7, and 10, and a single QTL controlled 2-5 traits, and most of these traits co-controlled total P accumulation, P dry matter production, P harvest index, K absorption of 100-kg seeds, and K harvest index. 【Conclusions】 In this study, 56 QTLs related to N, P and K utilization in rice were detected, and the QTLs with high contribution might be useful for rice breeding with high nutrition efficiency utilization for N, P and K by MAS. Additionally, 13 genomic regions of QTLs cluster distribution are important candidate regions for further study.