Abstract: 【Objective】 Germplasm resources is the base for crop breeding. The development of new high oleate peanutmaterials with various phenotypic characteristics is great significant for high oleic peanut breeding program. 【Method】Conventional variety Baisha 1016 and high oleic peanut line CTWE were used and their mutation types were determined by amplification and sequencing results of partial ORF of ahFAD2A and ahFAD2B. The oleic trait genotypes of two parents were confirmed by allele-specific PCR (AS-PCR). Oleic acid and linoleic acid content of each generation plants were detected by near infrared reflectance spectroscopy (NIRS) combined with gas chromatographic(GC) analysis. Double selection pressures of yield and oleic acid were used in 241 F_2:3 family lines and F₄ seeds, and the identification of phenotypic and AS-PCR were conducted on new selected materials.【Result】The amplification and sequencing results of partial ORF of ahFAD2A and ahFAD2B showed that the mutated sites of CTWE were the same as that of mutant F435 with a base substitution in (G448A) for ahFAD2A, and a single base pair insertion (442insA) for ahFAD2B while Baisha 1016 maintained wild type state on the same both sites. The AS-PCR analysis demonstrated that the parental lines differed in both genotypes and oleate content for ahFAD2A and ahFAD2B. The genotype of CTWE was o1_lo1_lol₂ol₂, and Baisha 1016 was OL₁OL₁OL₂OL₂, which was consistent with the sequencing results. Double selection pressures of yield and oleic acid were used in 241 F_2:3 family lines and 20 high oleate lines were selected, which the pods weight per plant was 30% higher than that of control of Jihua 2. Thirteen low-oleic family lines were eliminated by NIRS single particle detection on randomly picked 5 kernels of 20 high yield family lines respectively. All plants containing at least 1 kernels of high oleic acid type were detected, and four different genotypes in 7 lines were confirmed by AS-PCR. Four homozygous high oleate germplasm materials with various phenotypic characteristics and the yield 30% higher than that of control Jihua 2 were ultimately selected through field investigation and indoor test and ascertained by gas chromatography. Their 100-seed weights were between 54.00-75.29 g and belonged to medium-pod type. O/L ratio ranged from 28.66-41.19. The plant types of 11-3 and 13-2 were creeping type 3. They were both slight pod beak and slight pod reticulation. But the pod trait of 11-3 was bee waist shape with slight pod constriction, that of 13-2 was common shape with none pod constriction. The plant type of 15-2 was upright type and pod trait is common shape, none pod constriction, none pod beak and medium pod reticulation. The plant type of 16-1 was creeping type 2, pod trait was common shape, none pod constriction, slight pod beak and slight pod reticulation. 【Conclusion】 Four new medium-pod high oleic germplasm materials with different phenotypic characteristics were selected by AS-PCR assisted selection.

Key words: peanut, high oleate, phenotype, NIRS, gas chromatography, AS-PCR