关键词: 核桃, 脱水素基因, 定量RT-PCR, 单核苷酸多态性

Abstract: Reverse transcription PCR（RT-PCR）and rapid amplification of cDNA ends（RACE）technologies were used to clone JrDHN（GenBank accession No. KC503061.1）from leaves of walnut （Juglans regia L.‘Xiangling’）. Cloned JrDHN gene was 1 056 bp in length，containing 528 bp ORF encoded 175 amino acids. Amino acid sequence analysis indicated thatJrDHN possessed typical characters of LEA family. qRT-PCR analysis showed that the expression of JrDHN in Xiangling walnutwas induced by low temperature and peaked at 4 hours after exposed to 4 ℃ low temperature. Under the condition of natural overwintering，JrDHN gene expression increased firstly，reached to a peak in December，followed by decrease. It was deduced that JrDHN mayplay important roles in tolerating to cold stress. The transcripts of JrDHN could be detected in female flower，bark，flower bud and leaf of Xiangling walnut，especially high expression in female flower. Additionally，after analyzing single nucleotide polymorphism of JrDHN，30 SNPs and 11 Insertions/Deletions（Indels）were detected among 12 walnut accessions. Haplotype analysis showed that 12 walnut accessions were divided into ten haplotypes，and the haplotype diversity was 0.9697.

Key words: Juglans, dehydrin gene, qRT-PCR, single nucleotide polymorphism