Creation Of Peanut Germplasm With High Oleic Acid And Genotype Effect Analysis Of Ah FAD2A

Peanut(Arachis hypogaea L.) is an important oil and economic crop in China.Abundant genetic variations exist in oleic acid content of peanut. According to oleic acid content and the O/L ratio, peanut was divided into high oleic acid, medium oleic acid and average oleic acid. Improvement of the O/L value is one of the goals for peanut quality breeding. There are few high oleic acids peanut varieties in domestic, which is a larger gap compared to the developed countries. Therefore, the breeding of new high oleic acid peanut is an urgent and important task of peanut quality breeding in China. Germplasm resources are the base of crop breeding. The creation of new high oleate peanut materials with various phenotypic characteristics is significance for high oleic peanut breeding program. In this study, conventional variety Baisha 1016, Yuanza 9847, Ji 0212-2, Haihua1 and high oleic acid materials of CTWE and GYS01 were used in order to obtain high oleic germplasm materials with different phenotypic characteristics by hybridized combinations, molecular and chemical identification and plant laboratory test.AS-PCR molecular marker was used to screen every generation of double heterozygote.Near isogenic lines was built by self-cross of double heterozygote and the genotype effect was analysised.The main results were as follow:1. Six parents and their mutation types were determined by amplification and sequencing results of partial ORF of ah FAD2 A and ah FAD2 B. Results of partial ORF of ah FAD2 A and ah FAD2 B showed that the mutated sites of CTWE and GYS01 were the same as that of mutant F435 with a base substitution in(G448A) for ah FAD2 A, and a single base pair insertion(442ins A) for ah FAD2 B while Baisha1016, Yuanza9847,Ji0212-2, Haihua1 hao maintained wild type state on the same both sites.2. The oleic trait genotypes of six parents were confirmed by allele-specific PCR(AS-PCR). The AS-PCR analysis demonstrated that the parental lines differed in both genotypes and oleate content. The genotype of CTWE and GYS01 were o1lo1lol2ol2, and Baisha 1016, Yuanza 9847, Ji 0212-2, Haihua 1 were OL1OL1OL2OL2, which was consistent with the sequencing results.3. Double selection pressures of yield and oleic acid were used in F2:3 family lines and115 high oleate lines were selected, which the pods weight per plant was 30% higher than that of control of Jihua 2. Meanwhile, AS-PCR was used to detecting all plant for F2:3,screening genotype for homozygous recessive per plant. 38 creeping plants and 28 upright plants were ultimately selected through field investigation and indoor test and ascertained by gas chromatography. The oleic acid content was between 77.98% and 85.43%. O/L ratio ranged from 12.80-46.10.Their 100-seed weights were between 29.63 g and 96.14 g. 21 high oleic peanut germplasm with different phenotypic characteristics were selected in F6.There were seven high oleic peanut lines belonged to upright type, big-pod type. The oleic acid contents were between 80.57% and 83.36%. The 100-seed weights were between91.66 g and107.58 g. The pod weights of per-plant were between 24.55 g and 70.23 g.There were six high oleic acid materials with upright, belonging to medium-pod type.Their oleic acid content was between 80.50% and 82.47%, 100-seed weights were between72.92 g and 83.54 g. The pod weights of per plant were between 38.41 g and 59.27 g.Meanwhile, there were four materials belonging to creeping.The oleic acid content was between 80.40% and 82.62%, the 100-seed weights were between 81.32 g and 86.31 g,according to the 100-seed weights, regard these seeds as big-pod type. The pod weights of per plant were between 40.68 g and 67.34 g. The ending, the number of the high oleic peanut materials with creeping medium-pod type was four. These oleic acid contents were between 80.67% and 82.13%, the 100-seed weights were between 66.19 g and 79.17 g.The pod weights of per plant were between 58.07 g and 84.83 g.4. Six kinds of genetypes with OL1ol1OL2ol2, OL1OL1OL2ol2, ol1ol1OL2ol2,ol1ol1ol2ol2, OL1ol1ol2ol2 and OL1OL1ol2ol2 were detected among 464 individuals in F6. SSR markers were used to identify the background consistency of six genetypes. The results showed that the background consistency of the near isogenic lines was 93.58%.5. According the oleic acid contents of OL1OL1ol2ol2, OL1ol1ol2ol2 and ol1ol1ol2ol2,the dominant effect of OL1was-4.04% for oleic acid and the additive effect was-14.50%.However, the dominant effect of OL1 was 4.65% for linoleic acid and the additive effect was 13.68%.