中文摘要：

利用联合生物固氮是有效降低甘蔗生产成本的途径之一。在温室无氮栽培条件下，将内生固氮菌株A01分别接种到6个不同基因型甘蔗（GT24、GT9、YC84／153、GTl8、CP65／357和F172）中，在甘蔗伸长期测定＋1叶片的叶绿素含量（叶绿素a、叶绿素b）、光合作用参数净光合速率（Pn）、胞间COz浓度（Ci）、气孔导度（Gs）和蒸腾速率（Tr）和叶绿素荧光参数（Fu／Fm和φPSIIR），探讨内生固氮菌A01对不同基因型甘蔗光合生理特性的影响。结果表明，接种内生固氮菌A01对叶绿素含量、净光合速率、气孔导度、蒸腾速率在不同程度上有促进的效应；在暗适应下，对Fv／Fm有一定的抑制效应，但在光适应下，能提高PSII量子效率（φPSIIR）。

英文摘要：

Use of biological nitrogen fixing organisms is an effective approach to reduce the high cost of nitrogen fertilizer in sugarcane production system. The present experiment was conducted to investigate the effects of using nitrogen fixing bacteria（strain A01） on photosynthetic characteristics of different sugarcane genotypes during elongating stage. Six sugarcane varieties,v/z. ,GT24,GT9,YC84/153,GT18,CP65/357 and F172 were grown under nitrogenfree conditions in greenhouse. The endophytic nitrogen fixing bacteria was inoculated to sugarcane plants during seedling stage. And the chlorophyll content,photosynthetic rate（Pn）,intercellular CO2 concentration（Ci）, stomatal conductance（Gs）, transpiration rate（Tr ）, maximum quantum yield of PSII（Fv/Fm）and actual photochemical efficiency ofPSII（φPSIIR） were measured in ＋1 leaves of sugarcane during elongating stage. The results showed that the nitrogen fixing bacteria increased the chlorophyll content, Pn, Gs and Tr in the leaves of all the six sugarcane varieties. The chlorophyll fluorescence parameters such as Fv/Fm ratio was regulated in certain degree under dark adaptation, but φPSIIR was significantly enhanced in plants inoculated with the bacteria. The results suggested high utilization efficiency of nitrogen fixed by the endophytic bacterium.