接种内生固氮菌A01(Pantoea agglomeras)对甘蔗伸长期固氮生理特性的影响（英文）

Effects of nitrogen-fixing bacteria A01 on physiological characteristics of nitrogen fixation in sugarcane at elongating stage

【目的】探讨不同基因型甘蔗接种内生固氮菌A01的固氮生理特性表现,为内生固氮菌在甘蔗生产中的应用提供理论依据。【方法】将内生固氮菌株A01分别接种到6个不同基因型甘蔗品种（GT24、GT9、YC84/153、GT18、CP65/357和F172）中,在温室无氮栽培条件下,于伸长期调查甘蔗固氮酶、硝酸还原酶活性及氮含量。【结果】接种固氮菌A01后,不同时期不同甘蔗品种的＋2叶、＋3节间和根系的固氮酶活性、硝酸还原酶活性和氮含量表现均有不同;GT24、F172、GT9和GT24等4个甘蔗品种的节间、叶片和根系固氮酶活性均明显上升,GT24、GT18和F172的＋2叶硝酸还原酶活性均明显增加,其中以GT18增加最明显,其次为F172;GT9、GT24、GT18、F172和CP65/357等5个品种的＋3节间、＋2叶和根的全氮含量分别比对照增加0.06%-0.20%、0.02%-0.22%和0.02%-0.15%（绝对值）。【结论】接种固氮菌A01对F172和GT18的固氮生理特性有显著影响,可能是F172和GT18的内部环境更适于该菌生长。

【Objective】The present study was conducted to investigate the nitrogen-fixing physiological characteristics of different genotypic sugarcanes by inoculating with strain A01, in order to provide references for application of nitrogenfixing bacteria on sugarcane production. 【Method】Six genotypic sugarcane varieties viz., GT24, GT9, YC84/153, GT18,CP65/357 and F172 were inoculated with nitrogen-fixing bacteria strain A01（Pantoea agglomeras） by using sand culture,and the nitrogenase activities, nitrogen content of ＋2ndleaves, ＋3rdinternodes and roots were investigated from May to August, as well as nitrate reductase activities of ＋ 2ndleaves. 【 Result 】 The nitrogenase activities, nitrate reductase activities and nitrogen contents in ＋3rdinternodes, ＋2ndleaves and roots of different sugarcane varieties were differently affected by inoculating nitrogen-fixing bacteria strain A01 at different stages. The 4 sugarcane varieties viz., GT24,F172, GT9 and GT24 showed significant increasing in nitrogenase activities of internodes, leaves and roots at different stages after inoculated strain A01; the nitrate reductase activities in ＋2ndleaves of GT24, GT18 and F172 were found to enhance significantly, and GT18 was found to has the highest increment, followed by F172. The ＋3rdinternodes, ＋2nd leaves and roots of 5 sugarcane varieties（GT24, GT18, F172, GT9 and CP65/357） were found to present an increment of 0.06%-0.20%, 0.02%-0.22% and 0.02%-0.15% in nitrogen content after inoculation, respectively.【Conclusion】The nitrogen-fixing bacteria strain A01 could affect nitrogen-fixing physiological characteristics of sugarcane varieties F172 and GT18, might be the internal environment of F172 and GT18 were suitable for its growth.