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针对南雄烟区沙泥田烟草青枯病发病重的问题,采用大田试验方法,于植烟沙泥田耕层土壤中掺混了一定比例自然风化的红砂土(紫色土),研究了掺混后的土壤营养状况变化规律,并分析了沙泥田掺混红砂土对烟草青枯病的防治效果及原因。结果表明,在易发烟草青枯病的沙泥田耕层土壤中掺混红砂土150~450 m~3/hm~2后,土壤pH由酸性(4.78)渐变为中性(7.06),交换性钙离子含量增加了3~4倍,土壤中青枯病菌、细菌和真菌数量减少,而放线菌数量增加,青枯病发病率和病情指数比沙泥田分别下降了42.2%~73.5%和51.4%~81.1%。相关分析表明,pH、放线菌数量与青枯病发病率、病情指数均呈极显著负相关。在青枯病发病率高的植烟沙泥田耕层土壤中,掺混一定比例的红砂土可防治或减少烟草青枯病的发生。
Aiming to the serious problem of tobacco bacterial wilt in sandy soil of Nanxiong tobacco growing area, a certain proportion of natural weathered red sandy soil (purple soil) Soil nutrient status after the change of law and analysis Sand Sand mixed with red sand soil control of tobacco bacterial wilt and its causes. The results showed that the soil pH changed from acidity (4.78) to neutrality (7.06) after being mixed with 150 ~ 450 m ~ 3 / hm2 of sandy soil in topsoil, The content of calcium increased by 3 ~ 4 times, the number of bacterial wilt, bacteria and fungi in soil decreased, but the number of actinomycetes increased, the incidence of bacterial wilt and disease index decreased by 42.2% -73.5% and 51.4% respectively % ~ 81.1%. Correlation analysis showed that there was a significant negative correlation between pH and the number of actinomycetes and the incidence of bacterial wilt and disease index. In sandy soils where the incidence of bacterial wilt is high, red soils with a certain proportion of red sandy soil may prevent or reduce the occurrence of tobacco bacterial wilt.