李果实性状指标相关性分析及QTL初步定位

Correlation Analysis and Primary QTL Mapping of Fruit Traits in Plum

【目的】以东北地区李(Prunus salicina L.)吉林6号和龙园秋李两个品种的F_(1)群体为试验材料,对其单果质量、果实横径、果实纵径、果形指数、果肉厚度和总糖含量6个果实性状进行相关性分析和QTL定位。【方法】利用SPSS 23.0软件对6个果实性状进行表型和相关性分析;通过Map QTL 5.0软件对呈正态分布的果实性状进行QTL分析,根据区间作图法进行QTL定位,利用Map Chart 2.3软件对QTL连锁群进行绘图。【结果】李6个果实性状指标数据变异系数在6.09%~35.98%;果实横径、果实纵径和果肉厚度表型数据均呈正态分布;单果质量与果实横径呈极显著正相关,相关系数为0.959;果实横径与果实纵径、果肉厚度呈极显著正相关关系;总糖含量与其他指标间存在显著或极显著负相关关系。共定位到果实性状相关QTLs位点11个,其中果实横径和果实纵径相关位点各4个,果肉厚度相关位点3个,各位点分布在连锁群LG2、LG3、LG8和LG15上,其中在LG2、LG3和LG15连锁群上均定位到3个果实性状的位点,LOD值介于2.46~3.58之间,可解释9.8%~14.4%的表型变异。【结论】东北地区李果实各性状指标存在相关性,QTL位点在连锁群上存在成簇现象,为寒地李分子辅助育种提供理论基础。

【Objective】In this study,the F_(1)population of two cultivars of plum(Prunus salicina L.)in Northeast China,Jilin 6 and Longyuanqiuli,were used as research materials,and the correlation analysis and QTL mapping of six fruit traits(weight of single fruit,transverse diameter of fruit,vertical diameter of fruit,fruit shape index,thickness of pulp and content of total sugar)were carried out.【Method】SPSS 23.0 software was used to analyze the phenotype and correlation of 6 fruit traits.QTL analysis of fruit traits with normal distribution was carried out by Map QTL 5.0 software.QTL was located according to interval mapping method.Finally,the linkage group of QTL was mapped by Map Chart 2.3 software.【Result】The variation coefficient of 6 fruit traits was 6.09%-35.98%.The phenotypic data of transverse diameter of fruit,vertical diameter of fruit and thickness of pulp showed normal distribution.There was a significant positive correlation between weight of single fruit and transverse diameter of fruit,and the correlation coefficient was 0.959.The transverse diameter of fruit was significantly positively correlated with vertical diameter of fruit and thickness of pulp.There was a significant or extremely significant negative correlation between content of total sugar and other indicators.A total of 11 QTLs related to fruit traits were detected,including 4 QTLs related to transverse diameter of fruit,4 QTLs related to vertical diameter of fruit,and 3 QTLs related to thickness of pulp.All QTLs were distributed on linkage groups LG2,LG3,LG8 and LG15.Among them,3 QTLs related to fruit traits were detected on linkage groups LG2,LG3 and LG15.The LOD values were 2.46-3.58,which could explain 9.8%-14.4%of phenotypic variation.【Conclusion】There were correlations among the fruit traits of plum in Northeast China,and there were clusters of QTLs loci on linkage groups,which provided a theoretical basis for molecular assisted breeding of plum in cold region.