摘要
为害甘薯的马铃薯腐烂线虫（Ｄｉｔｙｌｅｎｃｈｕｓｄｅｓｔｒｕｃｔｏｒ）在土壤中以幼虫和成虫越冬，以幼虫为主。其中，７０％虫体的肠区部位出现类脂质体。质体呈圆形至椭圆形，无颗粒状物，每一虫体内常有５～６个质体，多者达１２～１５个。这种线虫的口针和背食道腺管清楚，但食道腺体部位结构模糊。低温试验结果表明，－５℃至－１５℃即可导致虫体产生类脂质体，而干燥和缺乏营养处理都不能引起虫体出现这一现象。将有类脂质体的线虫接种到甘薯感病品种薯块，２２℃，３０天后，虫体内的类脂液泡全部消失。不同地理位置、不同环境条件的甘薯茎线虫病病原线虫耐盐性有差异。盐滩附近病薯中的线虫耐盐性明显高于内陆地区线虫，在３％ＮａＣｌ溶液中，死亡率只有２１％。酸碱梯度试验证实，这种线虫存活的最适ｐＨ为６．
Ditylenchus destructor which causes sweet potato rot can overwinter as juveniles as well as adults in soil in China.Our observations found that the intestine area of 70% juveniles contained five or six lipoid droplets.The stylet and lumen of esophagus of the juveniles were distinct but the structure of esophagus was indistinct.Lower temperatures(-5℃ to -15℃)produced lipoid droplets;desiccation and lack of nutrients alone did not cause them.The lipoid droplets disappeared from specimens when inoculated into susceptible sweet potatoes at 22℃ for 30 days.Nematodes collected from three localities had different tolerance of salt concentrations,those from near a salt field survived better than those from inland.The mortality of those from near a salt field was 21% in 3% NaCl solution, compared with 53% of those from the other sites.The optimum pH for the nematode survival and reproduction was 6 2.
出处
《江苏农业学报》
CSCD
北大核心
1997年第1期36-39,共4页
Jiangsu Journal of Agricultural Sciences
基金
本研究为国家自然科学基金
