几种土壤处理方法影响三七幼苗生长及根腐病发生的研究

三七种植存在着严重的连作障碍，导致三七根腐病严重，产量降低、品质下降，严重制约了三七产业的发展。本研究为了寻找一种有效克服三七连作障碍中根腐病的土壤生态控制处理方法，比较了8种不同的土壤处理方法对三七幼苗生长及根腐病发生的影响。结果表明：8种土壤处理方法对克服连作障碍都有一定的效果；对试验处理的出苗率与存苗率、生物量的积累和减少根腐病的发生进行综合评价，比较结果为：田间蒸汽处理 大扫灭处理 威百亩处理 波尔多液处理 草木灰处理 高压蒸汽处理 活性炭处理 酒精处理。其中，田间蒸汽处理连作土壤后，三七的出苗率、存苗率与对照处理相比分别增加了18.0%和51.75%；生物量的积累也明显增加，根的鲜重和干重与对照处理相比分别增加了32.0%和26.8%；根腐病的发病率显著降低为9.0%，比对照降低52.6%。8种不同处理对三七的叶绿素含量、叶面积、茎粗、株高、根鲜重、根干重等的影响差异不显著。大扫灭处理和田间蒸汽处理是两种较好的土壤处理方法，但是田间蒸汽处理是克服三七连作障碍最有效且最生态的方法。土壤经过田间蒸汽处理后，土壤结构和土壤环境得到改善，土壤中的病原菌被杀灭，在一定程度上破坏了根腐病发生的土壤环境。因此，田间高温蒸汽处理土壤能够有效克服三七连作障碍，从而延长土壤的使用年限，达到克服三七连作障碍的目的。

Effect of Several Soil Treatments on Seedling Growth and Root Rot Disease of Panax notoginsen

The increasing severe soil obstacle to continuous cropping on Panax notoginsen would lead to severe root rot diseases, which seriously debased the quality of P.notoginsen and restricted the development of P. notoginsen industry. The effect of 8 soil ecological management methods on promoting seedling growth and inhibiting root rot diseases occurrence of P. notoginsen were compared in this study, in order to find out a effective soil ecological management method which could control root rot diseases of soil obstacle to continuous cropping on P. notoginsen. The results showed that all these 8 methods have some effect on increasing the field emergence rates,the seedling survival percentages and the underground biomass as well as reducing the occurrence of root rot diseases, the effect of the field steam treatment was the best among these 8 methods, and then was the dazom treatment, the metam treatment, the Bordeaux mixtrure treatment, the plant ash treatment, the high-pressure steam treatment, the activated treatment, and the alcohol treatment respectively. Compared with the control group, the field emergence rates and seedling survival percentages of the field steam treatment increased by 18.0% and 51.75%,respectively; the underground biomass also increased significantly, the root fresh weight and root dry weight increased by 32.0% and 26.8% compared with the control group; the occurrence of root rot diseases significantly inhibited to 9% which decreased by 52.6% than the control group. The effect of all these treatments on some growth indexes were not significant, such as chlorophyll content, leaf area, stem thickness, plant height, fresh and root dry weight, etc. The conclusion is that the dazom treatment and the field steam treatment are better soil treatment methods; however,the field steam treatment is the most effective ecological method to conquer the soil obstacle to continuous cropping on P. notoginsen. Through using the field steam treatment, the soil structure, soil environment are improved and the pathogens in soil are killed, which would destroy the soil environment for root rot diseases occurrence to some extent. Therefore,the field steam treatment could conquer the soil obstacle to continuous cropping on P. notoginsen,and prolong the soil utilization time and achieve the aim of conquering soil obstacle to continuous cropping on P. notoginsen.