小麦阿拉伯木聚糖含量的QTL分析及其与品质性状的关系

QTL Mapping for Arabinoxylans Content and Its Relationship with Processing Quality in Common Wheat

阿拉伯木聚糖是小麦中最重要的非淀粉多糖,对营养和加工品质有重要影响。采用IciMapping软件,对PH82-2/内乡188重组自交系群体（F2：6）的水溶性和总阿拉伯木聚糖含量进行QTL分析,在1B、4B、5B、5D和6B染色体上定位5个控制总阿拉伯木聚糖含量的QTL,分别解释5.6%~18.7%的表型变异;在1A、1B、5B、6B和7A染色体上定位5个控制水溶性阿拉伯木聚糖含量的QTL,分别解释4.3%~34.9%的表型变异。其中,1B、5B和6B染色体上影响水溶性和总阿拉伯木聚糖含量的QTL位于同一标记区间。1BL/1RS易位对水溶性和总阿拉伯木聚糖含量有显著作用,籽粒硬度对总阿拉伯木聚糖含量有显著作用。阿拉伯木聚糖含量,特别是总阿拉伯木聚糖含量,与快速黏度分析仪峰值黏度、稀澥值,以及面条品质黏弹性、食味呈显著相关,但相关系数受1BL/1RS易位和籽粒硬度影响。

Arabinoxylans （AX） are the hydrophilic nonstarch polysaccharides in wheat grain, and they play a critical role in food processing and nutrition quality. Quantitative trait loci （QTLs） for water-extractable （WE-AX） and total AX （TOT-AX） contents were identified and mapped using 240 recombinant inbred lines （RILs, F2：6） derived from the cross between PH82-2 and Neixiang 188. Besides, relationships between WE-AX and TOT-AX contents and protein content, Mixograph and Rapid Viscosity Analyzer （RVA） parameters were evaluated. Inclusive composite interval mapping identified five QTLs for TOT-AX content on chromo-somes 1B, 4B, 5B, 5D, and 6B, which explained 5.6%-18.7%of the phenotypic variations. Five QTLs associated with WE-AX content were mapped on chromosomes 1A, 1B, 5B, 6B, and 7A, explaining 4.3%-34.9%of the phenotypic variation. QTLs for TOT-AX content on chromosomes 1B, 5B, and 6B shared identical marker intervals with those for WE-AX content. 1BL/1RS translocation affected both TOT-AX and WE-AX contents, whereas, grain hardness only affected WE-AX content. TOT-AX con-tent had significant correlations with RVA parameters including peak viscosity, breakdown, final viscosity, setback, and Chinese White Salted Noodle quality traits （springness and flavor）, but the correlation coefficients were influenced by 1BL/1RS transloca-tion and the type of grain hardness.