西南山区马铃薯病虫害状况分析

西南山区由于其立体气候的多样性而使马铃薯发生多种病虫害，造成产量的不稳定性。通过一系列的问卷调查和大田观察取样以及实验室病理检测，结果说明晚疫病、病毒病和青枯病是本地区最重要的病害。晚疫病常年造成１０％～３０％的产量损失，且每隔数年有一次大流行而造成更大的产量损失。种薯因病毒和其它病菌感染而不同程度地影响到产量的发挥。青枯病的发病规律较为复杂且较难预测控制。这几种病害的发生程度与作物生长季节、海拔、种薯年龄、品种、农艺措施等等密切相关。现有品种间发现有抗晚疫病和青枯病的差异。土样根系样中发现有各种寄生性线虫存在，但其危害性特别是与青枯病的关系有待进一步研究明确。２８星瓢虫是本地区危害最重的害虫。本文还列举讨论了各种病虫害防治措施。

THE STATUS AND ANALYSIS OF POTATO DISEASES AND PESTS IN SOUTHWEST CHINA

It is important to know the specific disease and pest status of potato production,especially in the warmer regions.A series of studies,including general field surveys,phytopathological tests and assessment of yield losses,was conducted in Sichuan, Southwest of China.In general,potato viruses,late blight and bacterial wilt were the most important diseases.Seed tubers and plants were generally infected with viruses, which reduce production.A regular late blight epidemic every season causes severe yield loss.Incidence of bacterial wilt occurs irregularly.The severity of the three diseases was closely associated with season,altitude,seed age,variety and agronomic practices such as cutting of seed tubers. Genetic resistance,especially to late blight and bacterial wilt,was found.Parasitic nematodes were also found mostly in the soil samples,but the relationship between the incidence of bacterial and presence of nematodes was yet to be established in this area.Defoliation by 28 spot beetle was severe in certain circumstances in the area.Various possible approaches to control diseases and pests are discussed.