土壤理化性状对烟草黑胫病发生的影响

Effects of Physical and Chemical Properties of Soil on Occurrence of Tobacco Black Shank

为了解昆明市植烟土壤的理化性质与烟草黑胫病发生的关系,选择了4种不同的植烟地,在不施用任何农药的情况下,观察黑胫病的发生情况。结果表明:四个植烟点黑胫病的发生轻重依次为寻甸>宜良>禄劝>安宁;其中,水田种植较旱地种植烟草黑胫病的发生程度较轻;土壤中有机质含量高可促进土壤有益微生物增长,在一定程度可抑制烟草疫霉菌的生长,从而减少病原菌数量,减轻烟草黑胫病的发生程度;弱酸性的土壤(pH值低)可抑制烟草黑胫病发生。

In order to understand the relationship between physical and chemical properties of tobacco-planted soil and occurrence of tobacco black shank in Kunming city, four different tobacco-planted places were chosen to observe the occurring situations of tobacco black shank. The results showed that the occurring degree of tobacco black shank in four tobacco-planted places ordered as Xundian〉Yiliang〉Luquan〉An＇ning; the occurring degree of tobacco black shank in upland was more serious than that in paddy field; the high content of organic matters in soil can promote the growth of beneficial microorganisms in soil, thus inhibited the growth of Phytophthora nicotianae in a certain degree, then the number of pathogenic bacteria was reduced to alleviate the Qecurring degree of tobacco black shank; the weakly acidic soil （low pH value） can inhibit the occurrence of tobacco black shank.