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为探究烟株根际土壤营养状况与青枯病发生的关系,摸清影响烟草青枯病发生最关键的土壤养分因子,以从重庆市烟草青枯病发生十分典型的黔江植烟区采集的177份根际土壤样品为供试材料,测定并采用t检验、因子分析、判别分析等方法分析了土壤pH、有机质、碱解氮、速效磷、速效钾、交换性钙和镁、有效铁、有效锰、有效铜、有效锌、有效硼、有效钼13项指标。结果表明:土壤pH、有机质、速效钾、交换性钙、有效硼、有效钼含量偏低以及土壤碱解氮、交换性镁、有效锰含量偏高均有可能降低土壤的抑病效果,导致青枯病严重发生;烟草青枯病发病烟株根际土壤的钙镁比(4.04)明显低于健康烟株根际土壤的钙镁比(9.86);因子分析结果显示,土壤中低水平的有效钼、交换性钙可能是导致青枯病发生流行最主要的因子;通过判别分析可知,烟株根际土壤中速效钾、交换性钙、有效钼、有机质、有效硼5个成分的含量情况可能是判别青枯病发病与否的关键因子。
In order to explore the relationship between tobacco rhizosphere soil nutritional status and the occurrence of bacterial wilt, find out the most important soil nutrient factors that affect the occurrence of tobacco bacterial wilt, and collected from the typical tobacco planting area of Qianjiang in Chongqing, 177 rhizosphere soil samples were tested and analyzed. The soil pH, organic matter, available nitrogen, available phosphorus, available potassium, exchangeable calcium and magnesium, available iron, Effective manganese, available copper, available zinc, available boron, available molybdenum 13 indicators. The results showed that low soil pH, organic matter, available potassium, exchangeable calcium, available boron and available molybdenum, as well as high levels of soil available nitrogen, exchangeable magnesium and available manganese may reduce the soil disease control effect and lead to green The incidence of tobacco bacterial wilt disease rhizosphere soil calcium-magnesium ratio (4.04) was significantly lower than the healthy tobacco rhizosphere soil calcium-magnesium ratio (9.86); factor analysis showed that the soil is low-level effective Molybdenum and exchangeable calcium may be the most important factors leading to the prevalence of bacterial wilt. According to the discriminant analysis, the contents of available potassium, exchangeable calcium, available molybdenum, organic matter and available boron in rhizosphere soils may be Is to determine the incidence of bacterial wilt or not the key factor.