水、旱栽培条件下水稻叶片水势与抗旱性的相关分析及其QTL定位  

QTL Mapping and Correlations between Leaf Water Potential and Drought Resistance in Rice under Upland and Lowland Environments

作　　者：曲延英[1] 穆平[1] 李雪琴[1] 田玉秀[1] 文峰[1] 张洪亮[1] 李自超[1] 

机构地区：[1]中国农业大学农业部基因组学与遗传改良重点实验室/北京市作物遗传改良重点实验室

出　　处：《作物学报》2008年第2期198-206,共9页Acta Agronomica Sinica

基　　金：国家自然科学基金项目(30671281);国家高技术研究发展计划(863计划)项目(2006AA10Z158,2006AA100101);国家科技支撑计划项目(2006BAD13B01);国家重点基础研究发展计划(973计划)项目(2004CB117201,2003CB114301)

摘　　要：为了揭示叶片水势在水稻抗旱中所起的作用及其遗传机制,以越富和IRAT109为亲本构建了120个重组自交系,开展叶片水势与抗旱相关性及QTL定位的研究。重组自交系及亲本群体在旱田和水田两种条件下种植,于始穗期测量叶片凌晨水势和中午水势;以抗旱系数作为抗旱鉴定指标。结果表明,叶片水势在重组自交系间变异显著。相关性分析表明旱田中午叶片水势与抗旱系数及旱田单株产量呈极显著正相关,旱田叶片水势变化与抗旱系数及旱田单株产量呈极显著负相关,说明旱田中午叶片水势高且能保持凌晨基础叶片水势的品种更具抗旱性。共检测到6个叶片水势加性QTL,其中旱田凌晨叶片水势2个,分别解释表型变异的5.4%和7.9%,旱田中午叶片水势1个,解释表型变异的10.0%,旱田叶片水势变化2个,分别解释表型变异的11.6%和9.5%,水田叶片水势变化1个。未检测到水田叶片水势加性QTL。共检测到5对上位性效应QTL,其中旱田中午和凌晨叶片水势各检测到1对上位性QTL,水田凌晨叶片水势上位性QTL1对,水田中午叶片水势上位性QTL2对。抗旱系数共检测到3个加性QTL和2对上位性QTL。叶片水势遗传力较低,田间直观选择效果差,利用分子标记辅助选择将会提高选择效率。To reveal the role and genetic mechanism of leaf water potential （LWP） to japonica rice under various water status, 120 recombinant inbred lines （RILs） derived from a cross between IRAT109, an upland japonica rice, and Yuefu, a lowland japonica rice, were planted under both upland and lowland environments for mapping QTL associated with high LWP. LWP was measured at pre-dawn and mid-day. Drought resistance was evaluated with index of drought resistance （IDR）, which was the ratio of grain yield of upland treatment to that of lowland treatment at maturity. Significant variations of LWP were observed in RILs in both upland and lowland treatments. Correlation analysis indicated that LWP at mid-day in upland （WPU） was positively correlated （r = 0.256^＊＊; r = 0.259^＊＊） with IDR and yield per plant （YPU）, and water potential variation in upland （WDU） negatively correlated （r = -0.280^＊＊; r = -0.260^＊＊） with IDR and YPU. For LWP, 6 additive QTLs including 2 for LWP at pre-dawn in upland （WPIU）, 1 for WPU, 2 for WDU, and 1 for LWP variation in lowland （WDL） and 5 pairs of epistatic QTLs including 1 for WPU, 1 for WPIU, 1 for LWP at pre-dawn in lowland （WPIL）, and 2 for WPL were detected, respectively. Among the 6 additive QTLs, the 2 for WPIU （wpiul and wpiu4） and 1 for WPU （wpu6）, all donated by IRAT109, can explain 5.4%, 7.9%, and 10.0% of the phenotypic variances, respectively; the 2 for WDU, wdu6 from IRAT109 and wdy12 from Yuefu, can explain 11.6% and 9.5% of phenotypic variances, respectively. For IDR, 3 additive and 2 pairs of epistatic QTLs were identified. The broad heritability of LWP was low for direct selection in the field, but may be effective via marker-assisted selection.

关 键 词：抗旱系数 叶片水势 抗旱性 QTL 水稻(O.sativaL.) 

分 类 号：S511[农业科学—作物学]