3个棘孢木霉菌株对山新杨组培移栽苗生长和光合特性的影响

Effects of three Trichoderm aasperellumstrains on the growth and photosynthetic characteristics of tissue-cultured Populus davidiana×P.albavar.pyramidalis seedlings

为了收集具有促进林木生长作用的棘孢木霉(Trichoderma asperellum)功能菌株,本研究采用盆栽方法,以1年龄山新杨(Populus davidiana×P.albavar.pyramidalis)组培移栽苗为试材,分析了根施5×10~3 cfu·cm^(-3)土的3个棘孢木霉菌株Ta492、Ta536和Ta4分生孢子对山新杨幼苗生长状况、叶绿素含量、光合日变化及光响应曲线特征参数的影响。结果发现,经3个棘孢木霉菌株诱导后,杨树苗苗高、地径及生物量均不同程度地高于对照组(CK);杨树苗叶绿素含量和叶绿素a/b在多数时间点均显著高于CK(P<0.05),为光合速率的提高奠定了物质基础。同时,试验组杨树苗叶片的净光合速率(P_n)、气孔导度(G_s)、蒸腾速率(T_r)的日变化均高于CK,但变化趋势均与CK相同;并且,最大净光合速率(P_(n max))、光饱和点(LSP)、表观量子效率(AQY)等光响应曲线特征参数也在不同程度上高于CK。说明这3个棘孢木霉菌株均能有效提高山新杨的光合能力,促进其生长。并且,Ta536菌株对山新杨幼苗的诱导效果最好。

In order to collect Trichoderma asperellumstrains which could promote the growth of woody plants,pot experiment was carried out with one-year-old tissue-cultured seedlings of Populus davidiana×P.albavar.pyramidalis to study the effects of three strains of T.aspereullm：ACCC32492（Ta492）,ACCC30536（Ta536）and T4（Ta4）on the growth,the chlorophyll contents,diurnal variation of photosynthesis and light response curve characteristic parameters.The results showed that the height,basal stems diameter and biomass yields of the poplar seedlings inoculated with these T.asperellumstrains were higher than those of the control（CK）at different levels.At most of the time points,the chlorophyll contents and chlorophyll a/b ratios in the leaves of the inoculated poplars were significantly higher（P〈0.05）than those of CK which laid material foundation for the improvement of photosynthetic rate.The net photosynthetic rate（Pn）,stomatal conductance（Gs）and transpiration rate（Tr）of the poplars inoculated with these T.asperellumstrains increased compared with those of CK,but their respective time-course changing trends were the same as CK.The maximum net photosynthetic rate（Pn max）,the light saturation point（LSP）and the apparent quantum efficiency（AQY）of the poplars inoculated with T.asperellumstrains were higher than those of the CK.All the above results indicated that inoculation of the three T.asperellumstrains could significantly improve the photosynthetic efficiency and growth of poplar seedlings.T.asperellum ACCC30536 strain had the best effects on the growth of poplar seedlings.