马铃薯连作对根际土壤微生物生理类群的影响

Effect of potato continuous cropping on rhizosphere soil microbial physiological colony

【目的】探讨马铃薯连作对根际微生物生理类群的影响.【方法】以轮作(小麦)为对照,研究马铃薯连作1、3、5a根际土壤氨化细菌、亚硝化细菌、硝化细菌、纤维素厌氧细菌和好氧细菌的变化.【结果】种植小麦的轮作土壤细菌数量显著高于马铃薯连作土壤.在马铃薯块茎形成期土壤氨化细菌数量连作1a的比连作3a、连作5a的分别提高54.32%和224.68%,土壤硝化细菌数量连作1a的比连作3a、连作5a的分别提高42.86%和566.67%,土壤亚硝化细菌数量连作1a的比连作3a、连作5a的分别提高11.11%和104.08%.【结论】氨化细菌、硝化细菌、亚硝化细菌、好氧性纤维素分解菌和厌氧性纤维素分解菌的数量随着连作年限的增加数量显著减少.

[Objective] To investigate the change rule of rhizosphere soil microbial physiological groups under the continuous potato cropping. [Method] Pot experiments were conducted to study the changes of microbial physiological groups, such as ammonifiers, nitrifying bacteria, nitrite bacteria, erobic cellulose-de- composing bacteria and anaerobic cellulose-decomposing bacteria. [Result] The number of soil bacteria in wheat rotation soil were significantly higher than that of in the continuous potato cropping soil. In potato tuber formation stage, in 1 a potato cropping soil, the number of ammonifiers bacteria was respectively 54. 32~ and 224.68o/00 higher than 3 a and 5 a continuous potato cropping soil. The number of nitrifying bacteria was respectively 42. 86% and 566.67% higher than that of 3 a and 5 a continuous potato cropping soil. The number of nitrite bacteria was respectively 11.11% and 104. 08% higher than that of 3 a and 5 a continuous potato cropping soil. [Conclusion] The results suggest that the number of soil ammonifiers,ni- trifying bacteria, nitrite bacteria, aerobic cellulose-decomposing bacteria and anaerobic cellulose-decompo- sing bacteria are significantly reduced with the extension of potato planting time.