【摘要】 本研究探讨有益微生物复合菌剂(Effective Micoorganisms,EM)与木霉菌剂(Trichoderma,TRI)对三七连作障碍的消减作用及其作用机理。结果表明:EM和TRI处理的重茬三七出苗率、保苗率、产量均显著提高;EM处理的重茬土壤中的各营养指标均有所提高,TRI处理的重茬土壤中的速效钾等营养指标显著提高;HPLC分析发现,重茬三七根际土壤的酚酸含量未出现累积效应,可见三七连作障碍的发生并非是由化感物质的直接作用造成的,可能与化感物质对根际环境的间接作用有关;变性梯度凝胶电泳(DGGE)、荧光定量PCR(qRT-PCR)原位分析验证结果发现两种菌剂处理均能使连作土壤中的有益菌含量增加,有害菌含量减少,其中TRI的处理效果更为显著。说明这两种菌剂处理均可有效修复三七根际土壤,缓解连作障碍,同时显著提高三七产量,达到了预期效果。更多还原

【Abstract】 Two biological agents,EM and TRI,were applied in soil on a continuous cropping field of Panax notoginsengto study the remediating effect on the soil and the mechanism associated with the application.Treatments with the agents were found significantly increased the seedling emergence rate and survival rate as well as the root yield.All nutrients in the soil treated with EM were increased,while the available potassium in the soil treated with TRI significantly improved.The HPLC analysis showed no accumulation of phenolic acids in the rhizosphere soil by these treatments indicating that allelochemicals were not directly,but might indirectly,involved in the detrimental effect on P.notoginsengcaused by continuous cropping.The DGGE and qRT-PCR test results showed that both EM and TRI,especially TRI,could increase the population of beneficial,while depressed the harmful,bacteria in the soil.Thereby,the rhizosphere soil was effectively repaired by alleviating the deficiency brought about by the continuous cropping practice,and consequently,the growth and yield of P.notoginsengwas significantly recovered or improved.更多还原