外源GA3对毛竹实生苗茎秆生长及CesA基因表达的影响

以毛竹实生苗为试验材料,研究不同浓度外源GA₃（0,0.1,0.5,1 μmol·L^-1）对毛竹生长及CesA基因表达的影响。结果表明,与未经GA₃处理相比,施用外源GA₃后,毛竹实生苗茎节间和纤维细胞显著伸长,初生壁纤维素合成相关基因PeCesA2和PeCesA6相对表达量明显上调,次生壁相关基因PeCESA4和PeCESA4-1显著下调,傅里叶红外光谱分析（FTIR）,发现毛竹茎秆纤维素特征峰强度（1 060,1 160及1 373 cm^-1）随着GA₃浓度升高而逐渐增强,表明施用外源GA₃能够影响毛竹茎秆CesA基因表达,PeCesA2和PeCesA6的表达与外源GA₃促进纤维细胞伸长的过程存在一定联系。

Effects of Exogenous GA3 on the Growth of Stem and CesA Gene Expression in Phyllostachys edulis Seedling

We studied the growth of stem and CesA gene expression from the seedling in Phyllostachys edulis under the different concentration of exogenous GA₃(0, 0.1, 0.5, 1 μmol·L^-1). Compared with without GA₃ treatment, the internode and fiber cells of stem from the seedling elongated significantly, after treated by exogenous GA₃. The relative expression of primary wall-related PeCesA2 and PeCesA6 genes were significantly up-regulated, while that of secondary wall-related PeCesA4 and PeCesA4-1 genes were significantly down-regulated. By Fourier transform infrared spectroscopy(FTIR), the absorption intensity of characteristic cellulose peak(1 060, 1 160 and 1 373 cm^-1) from the stems enhanced with the increase of GA₃ concentration. Signifying the expression of CesA gene could be affected by the exogenous GA₃. The expression of PeCesA2 and PeCesA6 genes could be related to the process of fiber cells elongation.