Effect of Combined Treatment of Pasteurisation and Coniothyrium minitans on Sclerotia of Sclerotinia sclerotiorum in Soil
Effect of Combined Treatment of Pasteurisation and Coniothyrium minitans on Sclerotia of Sclerotinia sclerotiorum in Soil
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DOI：
10.1007/s10658-005-2331-4
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发表时间：
2005-10
影响因子：
1.8
通讯作者：
A. Bennett;C. Leifert;J. Whipps
中科院分区：
文献类型：
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作者：
A. Bennett;C. Leifert;J. Whipps
随着土壤熏蒸剂甲基溴的逐步淘汰，土壤传播的植物病原体如核盘菌的综合防治变得越来越重要。已经发现两种可替代的控制方法可以降低菌核的存活力，这两种方法是对土壤进行蒸汽灭菌（巴氏灭菌）或施用真菌寄生物盾壳霉（Coniothyrium minitans）。这项工作研究了这两种控制措施相结合的可能性。采用80 °C高温灭菌3 min，模拟田间蒸土机可能达到的温度，对土壤进行灭菌处理，然后将盾壳霉（Coniothyriumminitans）施于灭菌土壤，以评价综合防治措施对降低核盘菌（S.sclerotiorum）菌核活力的效果。在两种土壤类型中发现了类似的结果。单独使用的任何一种方法都能有效地减少有活力的菌核的数量，但当两种方法结合使用时，没有看到菌核活力的进一步减少。发现盾壳霉比未处理的菌核更快地定植在巴氏灭菌的菌核上，并且可以看到，在存在菌核的巴氏灭菌的土壤中，盾壳霉的数量增加。还进行了实验以研究巴氏灭菌后生物防治剂对土壤的施用时间对菌核感染的影响。在此，使用了两种不同的S. sclerosis分离株，具有相似的结果。在巴氏灭菌后立即将C. minitans施用到土壤中导致由真菌寄生虫引起的菌核感染，但是在土壤巴氏灭菌后7天或更长时间施用导致生物防治剂从菌核的低回收率，这可能是由于真菌寄生虫被首先定殖在菌核上的其他真菌的存在所掩盖。
Integrated control of soil-borne plant pathogens such asSclerotinia sclerotiorumis becoming more important as the soil fumigant methyl bromide is being phased out of use. Two alternative methods of control that have been found to reduce viability of sclerotia are steam sterilisation (pasteurisation) of soil or the application of the mycoparasiteConiothyrium minitans. This work investigated the possibility of integrating these two control measures. Soil was pasteurised in an autoclave, using a temperature of 80 °C for 3 min to simulate the possible temperatures reached by soil steaming machines for field use.Coniothyrium minitanswas subsequently applied to the pasteurised soil to assess the effects of the combination of control measures in reducing sclerotial viability ofS. sclerotiorum. Similar results were found in two soil types. Either method used individually was effective in decreasing the number of viable sclerotia, but no further reduction in sclerotial viability was seen when the two methods were combined.Coniothyrium minitanswas found to colonise pasteurised sclerotia significantly quicker than untreated sclerotia, and it was seen that there was an increase in number ofC. minitansin pasteurised soil in the presence of sclerotia. Experiments were also conducted to investigate the effect of application timing of the biocontrol agent to soil following pasteurisation, in relation to sclerotial infection. Here, two different isolates ofS. sclerotiorumwere used, with similar results. Application ofC. minitansto soil immediately following pasteurisation resulted in sclerotial infection by the mycoparasite, but application 7 days or more after soil pasteurisation resulted in low recovery of the biocontrol agent from sclerotia, possibly due to the mycoparasite being masked by the presence of other fungi which colonised the sclerotia first.