荧光假单胞菌对樱桃根系呼吸和幼苗生长的影响

【目的】合理利用土壤有益微生物改善土壤环境，有助于提高作物产量与品质。樱桃根系适应性普遍较差，对土壤理化和生物环境变化反应敏感。探讨土壤接种荧光假单胞菌等根际促生细菌对根系功能及幼苗生长的影响效应，可为樱桃园根际环境调控提供参考依据。【方法】以土壤灭菌的钵栽山樱幼苗为试材，测定根系呼吸代谢相关指标，研究根系呼吸等生理功能对定量接种荧光假单胞菌的响应特征。【结果】幼苗根系呼吸途径以糖酵解-三羧酸循环-细胞色素途径（EMP-TCA-COX）为主。接种处理结束后5 d时，幼苗根系总呼吸速率未发生显著改变；20-35 d时接种处理EMP途径以及TCA途径呼吸速率降低，从而导致总呼吸速率较对照分别降低了34.9%和30.9%，而在50 d时接种处理的EMP途径及TCA途径呼吸速率升高，使得根系总呼吸速率较对照显著提高了135.8%。接种荧光假单胞菌处理后5 d时显著提高了丙酮酸激酶（PK）、苹果酸脱氢酶（MDH）、琥珀酸脱氢酶（SDH）以及葡萄糖-6-磷酸脱氢酶（G-6-PDH）活性，降低了磷酸果糖激酶（PFK）活性。而接种处理后20 d时PK活性高于对照，PFK和G-6-PDH活性低于对照，其余根系呼吸途径相关酶活性与对照相比无显著差异。接种处理35 d时PFK活性较对照提高了127.0%，50 d时G-6-PDH活性升高至对照的2倍，其余酶活性与同期对照相比虽有差异但不显著。土壤接种荧光假单胞菌的幼苗叶片数增加了16.7%，茎粗增加了9.3%，说明接种处理促进了植株生长。【结论】灭菌条件下接种荧光假单胞菌影响山樱幼苗根系呼吸功能及生长，接种OD值为0.4的菌液（共6次）处理后20-35 d，引起了根系呼吸途径分配比例变化，部分相关酶活性发生改变，影响根系总呼吸速率，进而引起植株形态指标的改变。

Effects of Pseudomonas fluorescens Inoculation on Root Respiration and Seedling Growth of Cherry

【Objective】 Rational utilization of soil microbial for improving soil environment is helpful to promote plant yield and quality. The adaptation of cherry root is bad, so it is sensitive to the change of soil environment. The objective of the experiment is to discuss the mechanisms of Cerasus sachalinensis (Fr.Schu) seedlings responding to soil sterilization and inoculation of Pseudomonas fluorescens, thus providing an academic and practical basis for regulating the rhizosphere soil.【Method】In order to find the influence of inoculation P. fluorescens on plant root function, C. sachalinensis(Fr.Schu) seedlings were used as materials to measure the correlative indexes of root respiration metabolism.【Result】Compared with soil sterilization, glycolysis, tricarboxylic acid cycle, and cytochrome oxidase pathways were also the dominant respiratory pathways from 5 d to 50 d after C. sachalanensis seedlings were subjected to CK and SS+Pseu treatments. On 5th d, there was no significant difference in total respiration rate of the roots between SS+Pseu treatment and CK, however, on 20 and 35th d, in SS+Pseu treatment, the total respiration rate of the roots was lower than that in the CK, while the total respiration rate of the roots in the SS+Pseu treatment was higher than that in CK on 50th d. On 5th d, the activities of PK, MDH, G-6-PDH, SDH were significantly increased in the SS+Pseu treatment, however, the activity of PFK was significantly decreased. On 20th d, the activity of PK was significantly increased in the SS+Pseu treatment, however, the activities of PFK and G-6-PDH were significantly decreased. On 35th d the, activity of PFK was increased by 127.0%, On 50th d the activity of G-6-PDH was increased by two times. Though, there were some differences between CK and SS+Pseu treatment, however, these differences were not significant. In SS+Pseu treatment the stem diameter and leaves number were significantly increased by 9.3% and 16.7%. Inoculation with P. fluorescens was helpful to plant growth.【Conclusion】Inoculation with P. fluorescens could influence plant growth and root function. In general, 20 d after the end of continuous inoculation (six times) with the bacterial liquid whose OD value was 0.4 could change the rate of respiration pathways, key enzyme activities via influence the function of roots, and then promoted plant growth.