水稻光合作用及相关生理性状的QTL分析(英文)

Quantitative Trait Locus for Photosynthesis and Its Related Physiological Traits in Rice(Oryza sativa L.)

为了探讨光合作用及相关生理性状的遗传规律，利用由籼稻品种IR24和粳稻品种Asominori杂交衍生的65个染色体片段置换系（Chromosome Segment Substitution Lines，CSSLs）为材料，研究了水稻光合作用及相关生理性状的QTL。在水稻抽穗后7d测定叶片光合速率（Pn）、蒸腾速率（Gs）、气孔导度（Tr）、细胞间隙CO2浓度（Cr）、叶绿素含量（CHL）、全氮含量（TEN）。共检测到10个QTLs，分布于第1、3、4、5、7、8和10染色体上，LOD值在2．77—8．42之间，贡献率为9．5％～46．5％。其中仅有控制气孔导度的qGs-8与控制叶绿素含量的qCHL-8以及第10染色体上控制气孔导度的gGs-10与控制细胞间隙CO2浓度的qCi-10位置相同，分别位于第8染色体上标记R727和第10染色体上标记C1166附近。其他QTL在染色体上的位置不同，暗示了水稻光合功能遗传规律的复杂性。

In order to explore the genetic basis for photosynthesis and its related physiological traits, sixty-five chromosome segment substitution lines （CSSLs）, derived from a cross between an indica cultivar IR24 and a japonica cuhivar Asominori of rice （ Oryza sativa L. ）, were utilized for mapping quantitative trait loci （QTL） for photosynthesis and its related physiological traits. Net photosynthesis （Pn）, stomatal conductance （ Gs ）, transpiration rate （ Tr ）, intercellular CO2 concentration （ Ci）, leaf chlorophyll （CHL）, and total leaf nitrogen content （TLN） in flag leaves were measured at heading stage. The CSSLs showed transgressive segregation for many of the traits, and significant correlations were observed for most of the traits. In total, ten QTLs were detected on chromosomes 1, 3, 4, 5, 7, 8, and l0 with a range of percentages of variance explained （PVE） from 9.5% to 46.5%. LOD scores of these QTLs ranged from 2.77 to 8.42. A consistent location was mapped for a QTL controlling stomatal conductance （ qGs-8 ） and leaf chlorophyll concentration （qCHL-8） in the vicinity of R727 on chromosome 8 and for a QTL controlling stomatal conductance （qGs-10） and intercellular CO2 concentration （qCi-10） in the vicinity of C1166 on chromosome 10. No other overlapping loci associated with different traits were detected. These results indicated that the genetic mechanism of photosynthesis was complex in rice.