QTL Preliminary Mapping Of Fatty Acid In Peanut

Peanut is a widely cultivated cash crop and oil crop in the world.It is an important source of oil and protein.With the improvement of people's living standard and diet structure,the total consumption and proportion of peanut oil are increasing year by year,and the market potential of peanut industry is great.As people pay more attention to health,peanut varieties are required not only to have high oil content,but also to have good quality.Fatty acid is an important component that affects peanut commodity quality and fat nutrition.Therefore,how to increase the content of beneficial fatty acids in peanut oil has become the main direction of improving the quality of international oil crops.The QTL study of peanut oil content,protein and fatty acid composition can provide an important theoretical basis for peanut breeding.In this study,140 F₂segregated populations were constructed by hybridization of Weihua 8 and 12L49.The genetic map of peanut SSR markers was constructed by using the SSR molecular marker technology and the complete interval mapping method.On the basis of this map,QTL mapping was conducted with the phenotypic data.The main results were as follows:1.The results showed that peanut oil content,protein and fatty acid content were typical quantitative characters.The results of correlation analysis showed that oil content was positively correlated with oleic acid content,and negatively correlated with linoleic acid,palmitic acid,linolenic acid and docosanc acid content.The content of oleic acid was negatively correlated with the content of linoleic acid,palmitic acid,linolenic acid and docosanc acid.The content of linoleic acid was positively correlated with the content of palmitic acid,linolenic acid and docosanc acid.The content of palmitic acid was positively correlated with the content of linolenic acid and docanoic acid.The content of linolenic acid was positively correlated with the content of docosanoic acid.There was a negative correlation between the content of arachidic acid and docosanoic acid.2.In this study,429 pairs of SSR primers were used for polymorphic screening and 103pairs showed polymorphism compared with their parents,accounting for 24.01%of the total number of primers.By using these polymorphic primers and a genetic linkage map containing20 linkage groups was obtained by QTL IciMapping 4.1 software.The total length of the map was 3592.35 cM,and the average distance between the markers was 34.88 cM.The number of markers in different linkage groups ranged from 3 to 9,and the length was between65.71-381.83cM.Compared with the publicly published integrated map,the linkage map has good consistency.3.Combined with molecular data and phenotypic data of peanut seed oil content,protein,oleic acid,linoleic acid,palmitic acid,linolenic acid,arachidic acid and docosanoic acid,16QTLs were detected by QTL IciMapping 4.1 software.Among them,3 QTLs were related to oil content,1 QTL was related to protein content,3 QTLs were related to oleic acid content,2QTLs were related to linoleic acid content,4 QTLs were related to linolenic acid content,2QTLs were related to arachidic acid.The phenotypic variation ranged from 2.6240%to18.5971%.