马铃薯枯萎病初侵染来源及栽培与发病的关系

马铃薯枯萎病(Fusarium oxysporum)是一种重要病害,重茬地发病重,对马铃薯生产造成威胁。为了解该病发生规律,试验进行了枯萎病初侵染来源及栽培与发病关系的研究。盆栽试验结果表明,土壤接菌的植株萎蔫率、病株率及病薯率分别为36.7%、58.3%和71.3%,播种带病种薯的植株萎蔫率、病株率及病薯率分别为11.7%、18.0%和21.4%,由此明确土壤带菌是主要的初侵染来源。田间不同施肥种类及栽培方式对病害发生的影响。试验结果表明:合理施肥均能延缓植株发病,其中施用尿素的植株萎蔫率、病薯率分别是13.3%、47.1%,显著低于CK及其它施肥处理,产量达到最高,为2 202 kg/667 m2;其次是马铃薯专用肥及碳酸氢盐类处理,均比CK植株萎蔫率低,产量有所增加。采用覆膜起垄栽培可以有效降低病薯率。

Primary Infection Source of Fusarium wilt and Relationship Between Cultivation and Incidence

Fusarium wilt(Fusarium oxysporum) of potatoes is one of the important diseases which threaten the potato production,especially in continuous cropping fields.In order to understand the occurrence of the disease,the experiments were conducted to study the primary infection sources of Fusarium oxysporum,and the relationship between the disease incidence and cultivation mode.Pot experiments showed that the rate of plant wilting,diseased plants and tubers in the soil inoculated with the bacteria was 36.7%,58.3% and 71.3%,respectively,while the rate of plant wilting,diseased plants and tubers derived from diseased potatoes was 11.7%,18.0% and 21.4%,respectively,proving that the primary infection source was bacteria inoculated soil.The results of plant disease occurrence in the field with different types of fertilizer application and cultivation modes showed that rational fertilization could postpone the morbidity of potato plants.The rate of plant wilting and diseased tubers was 13.3% and 47.1%,respectively,when applied with urea,significantly lower than the control and other treatments,with the yield being highest,2 202 kg / 667 m2.The control effect of specialized fertilizer and bicarbonate ranked second.Use of ridging with plastic mulching effectively reduced the rate of diseased tubers.