The quantity of different microorganisms, biochemical activity and the enzyme activity of the first- and second-generation of Pinus massoniana under similar condition were studied by using the methods of microorganism cultivation and laboratory analysis on soil microorganism biochemical activity and enzyme activity. The results showed that all the indexes of the soil microorganism quantity, biochemical activity and the change of soil enzyme activity (except Nitrification) in the first- and second-generation stands of P.massoniana showed the vertical distribution characteristics. The indexes decreased with the increase of soil depth, which reached significantly different. All the indexes of the second-generation P.massoniana about the soil microorganism quantity, biomass, biochemical activity and the change of soil enzyme activity were higher than those of first-generation. There was a significant positive correlation between bacterial amount and biomass carbon, and between bacterial amount and respiration. There was a very significant or significant positive correlation between the quantity of actinomyce, fungus and biomass carbon, respiration, invertase and catalase.

[目的] 克隆马尾松谷胱甘肽过氧化物酶基因，并对其进行功能研究。[方法] 采用RACE技术克隆基因cDNA序列，实时荧光定量PCR检测基因在马尾松干旱胁迫下的表达模式，花序浸泡法转化拟南芥，并对转基因与野生型拟南芥的生长表型和根系生长进行分析。利用荧光显微镜技术对转基因拟南芥不定根进行GFP荧光检测。[结果] 克隆到1个871 bp的GPX基因全长cDNA序列，命名为PmGPX6。PmGPX6包括513 bp的完整开放阅读框，编码170个氨基酸残基。PmGPX6蛋白与油松PtGPX蛋白同源性达95%。PmGPX6在马尾松根中高表达，茎、叶中表达量低。在干旱胁迫下，PmGPX6在根、茎、叶中的表达量均在第15天达到最大，随后出现下降趋势。过表达PmGPX6与野生型拟南芥植株在正常水分条件下表型与根长差异不大，但在干旱胁迫下，转基因植株根系更长。转基因拟南芥根在蓝色光激发下能发出强烈的绿色荧光，表明PmGPX6基因能高效表达。[结论] 推测PmGPX6可能参与马尾松干旱胁迫应答。