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Peanut (Arachis hypogara L.) is one of the important oil crops, cultivation of high oil peanut varieties peanut breeding in China has become an important goal. However, the high oil content of peanut varieties on our production applications, mainly due to the lack of high oil germplasm resources of the cultivated species, few studies of the genetic mechanism of oil content and oil content of the environmental impact large resulting in phenotypic selection in breeding difficulties . Many studies have shown that wild peanuts have some cultivated peanuts do not have good traits, such as a high degree of resistance to leaf diseases and viral diseases and even immune. However, at home and abroad on the wild peanut oil content is less. Therefore, identification of wild peanut oil content necessary to explore the stable high oil wild peanut germplasm to explore the use of wild peanuts resources to broaden the genetic base of the cultivars of peanut oil content, the establishment of the oil content of molecular markers. Association analysis and linkage analysis is the main method of studying molecular markers of target traits. In natural populations, as the materials, by linkage disequilibrium-based association analysis method can also analyze the target traits of a plurality of materials, can also analyze a plurality of traits, particularly suitable for the quantitative traits such as oil content analysis. Many studies have shown that homology exists between the different species of wild peanut, between Crossability. Therefore, you can take advantage of the natural populations of wild peanut association analysis. This study in order to save the national wild peanut germplasm nursery wild peanut the years many duplicate detection oil content, these wild peanut polymorphism analysis by SSR technology applications associated analysis methods, the establishment of the oil content of molecular markers. The main findings are as follows: 1. To utilize GB/T14488.1-93 and GB/T17377-1998 methods, years of repeated identification of resources (including diploid and tetraploid) oil content and fatty acid composition of 86 wild peanut clear the the wild peanut oil content and fatty acid composition of genetic variation. The results showed that the the wild peanut oil content, minimum, maximum and average values ??were 53.98%, 63.74% and 56.76%, respectively, are higher than the corresponding values ??of the cultivated species peanut resources, palmitic acid, stearic acid, arachidic acid, and peanut acid content similar to the cultivated species, linoleic acid and behenic acid content is slightly higher than the cultivated species, while the oleic acid content is slightly lower than the cultivated species. Discover high oil germplasm (≥ 55% oil content) 81 copies, the special high oil germplasm (oil content ≥ 58%) 16 copies, respectively, accounting for 94.19% and 18.60% of the identification of resources, of which oil amounted to 63.74% of the species The qualitative A. appressipila the highest oil content of germplasm resources found wild peanut. 2 to 20 copies of high oil wild peanut material with clear and rich polymorphism SSR primer amplification of its genome, 425 polymorphic bands were amplified with 46 pairs amplified. The number of bands for each primer pair amplified 2-21, average 9. Wherein primer 2E6 highest efficiency of amplification, and 14 parts of 20 parts of material zone can be separated. Most the double primer combinations 2E6/PM403 ability to identify, capable of 18 of the 20 were separate. 5 groups, three primer combinations 20 materials can be completely distinguish 2E6/PM403/1B9, 2E6/PM403/9A7, 2E6/PM403/10H1A, 2E6/PM403/PM201, 2E6/PM403/PM458, which combination of three primers 2E6 / PM403/10H1A for the best primer combinations. The integrated use of the national unity of the wild peanut material number, name of the primers and molecular data to establish the identity of 20 wild peanut oil germplasm DNA fingerprint database. 79 diploid wild peanut material from 346 pairs of primers screened 87 pairs amplified bands clear polymorphic SSR primers covering all wild peanut A genome and B genome linkage groups its genome DNA amplification, 87 primers produced a total of 756 polymorphic loci, application the STRUCTURE software SPAGedi software analysis of the population structure and Kinship kinship coefficient. The results show that the wild peanut involved are divided into two subgroups, between two materials Kinship <0.2 and about 75%, indicating that 79 parts wild peanut material between distantly related, reflecting the wild peanut extensive resources and diversity. 4. Using TASSEL2.1 Software association analysis, a total of 65 SSR markers associated with the target traits sites detected. Among them, seven sites associated with the oil content phenotypic variation explained by the variation of the range of 0.0218-0.0468, which sites the highest contribution rate for the XY-27-1. 2 sites with palmitic acid content associated phenotypic variation explain the rate of variation of the range of 0.0268-0.0361 9 loci associated with oleic acid, the phenotypic variation explained by variation range of 0.0292-0.0543, the highest contribution rate sites POCR39-140. 13 sites linoleic acid associated phenotypic variation explained by the variation of the range of 0.0215-0.0609, the highest contribution rate sites POCR39-140. 18 sites with arachidonic acid associated with the highest bit of phenotypic variation explained by the variation of the range of 0.0086-0.0438, the contribution rate point for POCR39-140. 8 sites behenate associated phenotypic variation explained by variation range 0.017-0.0466, the contribution rate of the highest sites for POCR39-140. 8 sites with 24 four-carbon alkyl acid associated with phenotypic variation explained ranged 0.0063-0.0206 for XY-89-258, the highest contribution rate sites. All marked phenotypic variance explained by variation range 0.0063-0.0609, with an average of 0.0303. 5 by allelic variation effects analysis found associated with oil content sites allelic variation in 5 alleles have increased maximum efficiency effect, XY-27-1, and the synergistic effect of GI620-234 (6.24), two alleles have less pleiotropic effects, XY-2-184 Less effective maximum effect (-0.91). Palmitic acid associated sites two allelic variation are less pleiotropic effects, which, PMc660-214 effective reduction effect (-0.54). Allelic variants associated with oleic acid sites, four synergistic allelic variation POCR39-140 maximum synergistic effect (13.67), 5 less efficiency alleles XY-2-162 Less effective maximum effect ( -13.7). Allelic variants associated with linoleic acid sites, the seven synergistic allelic variation, six less effective alleles, the largest the synergistic effect of the XY-2-162 (12.31), XY-38-166 effective reduction effect maximum (-12.31). Allelic variation associated with arachidonic acid sites, seven synergistic allelic variation, 11 less efficient alleles XY-95-175 synergistic effect (1.3), XY-38-166 and 4B11- 200 Less pleiotropic effects (-1.18). Alleles and allelic variations the behenate associated sites, six synergistic, two less efficiency alleles, the synergistic effect of the XY-95-175 (2.37), POCR39-140 effective reduction effect ( -2.04). Allelic variation associated with 24 four-carbon alkyl acid sites, three synergistic allelic variation, 5 and less effective alleles, the synergistic effect of the XY-2-162 and XY-89-258 (1.21) , XY-27-5 Less pleiotropic effects (-1.22).
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