Abstract:

The complete coding sequence of D27 gene was cloned according to the sequence information of D27 in woodland strawberry genome，which is the key gene in biosynthesis pathway of phytohormone strigolactone. Phylogenetic tree was constructed by MEGA5.0 based on amino acid sequences of D27 genes derived from woodland strawberry and other plants. The results revealed that D27 gene in woodland strawberry possessed high sequence homology with other known D27 genes. Three different treatments were carried out in current study，which consisted of normal phosphorus application （control），phosphorus starvation and mycorrhiza fungi symbiosis under phosphorus starvation. Using plasma-atomic emission spectrometry（ICP-AES），the phosphorus content in Fragaria vesca under three treatments was detected. The results showed that the phosphorus content under mycorrhiza fungi symbiosis treatment was significantly higher，while the phosphorus content under phosphorus starvation was significantly lower when compared with control. Real-time quantitative PCR analysis showed that D27 was upregulated by 11 times in mycorrhizal roots and by 7 times in phosphorus starvation roots in comparison with that of the control roots，respectively. It revealed that the expression of D27 was regulated by both phosphorus level and mycorrhiza formation.

Key words: Fragaria vesca, D27, phylogenetic analysis, phosphorus content, expression analysis