Hamidi Negin, Hajihassani Abolfazl
Department of Plant Pathology, University of Georgia , Tifton, GA 31793.
J Nematol. 2020;52:1-10. doi: 10.21307/jofnem-2020-043.
Oilseed radish and oat are cool season annual crops that are potentially used as "trap" or "biofumigant" crops for the suppression of plant-parasitic nematodes in soil. Cultivars of oilseed radish (Carwoodi, Cardinal, Final, Image, Concorde, Control, Eco-Till, Karakter and Cannavaro), white (Tachiibuki) and black (Pratex) oats were evaluated for their ability to reduce reproduction of three root-knot nematode species: , race 3, and race 1. Nematode penetration and development were also evaluated using selected resistant and susceptible cultivars under greenhouse conditions. Root galling severity, number of eggs per gram of fresh root, and rate of reproduction varied among the cultivars in response to nematode infection. Oilseed radish cv. Carwoodi was resistant to , whereas Karakter and Concorde were maintenance hosts allowing the nematode to maintain or increase its population on the plants. For , Control and Carwoodi oilseed radish and Tachiibuki oat were resistant hosts. The cultivars that supported little reproduction of were Karakter and Carwoodi radish, and Tachiibuki oat. Comparable numbers of nematodes entered the roots of susceptible and resistant cultivars of oilseed radish and oat during early stages of infection. However, the development of the nematodes as evident from counting young and egg-laying females in roots were significantly decreased or inhibited in the resistant cultivars compared to the susceptible cultivars indicating that resistance occurs at post-infection stages. Histopathological examinations of galled-root tissues also revealed the susceptibility and resistance responses of selected cultivars of oilseed radish and oat to these nematode species. Oilseed radish and oat are cool season annual crops that are potentially used as “trap” or “biofumigant” crops for the suppression of plant-parasitic nematodes in soil. Cultivars of oilseed radish (Carwoodi, Cardinal, Final, Image, Concorde, Control, Eco-Till, Karakter and Cannavaro), white (Tachiibuki) and black (Pratex) oats were evaluated for their ability to reduce reproduction of three root-knot nematode species: , race 3, and race 1. Nematode penetration and development were also evaluated using selected resistant and susceptible cultivars under greenhouse conditions. Root galling severity, number of eggs per gram of fresh root, and rate of reproduction varied among the cultivars in response to nematode infection. Oilseed radish cv. Carwoodi was resistant to , whereas Karakter and Concorde were maintenance hosts allowing the nematode to maintain or increase its population on the plants. For , Control and Carwoodi oilseed radish and Tachiibuki oat were resistant hosts. The cultivars that supported little reproduction of were Karakter and Carwoodi radish, and Tachiibuki oat. Comparable numbers of nematodes entered the roots of susceptible and resistant cultivars of oilseed radish and oat during early stages of infection. However, the development of the nematodes as evident from counting young and egg-laying females in roots were significantly decreased or inhibited in the resistant cultivars compared to the susceptible cultivars indicating that resistance occurs at post-infection stages. Histopathological examinations of galled-root tissues also revealed the susceptibility and resistance responses of selected cultivars of oilseed radish and oat to these nematode species.
油菜萝卜和燕麦是冷季一年生作物，有可能用作“诱捕”或“生物熏蒸”作物，以抑制土壤中的植物寄生线虫。对油菜萝卜品种（卡伍德、红衣主教、决赛、图像、协和、对照、生态免耕、性格和卡纳瓦罗）、白燕麦（立吹）和黑燕麦（普拉泰克斯）进行了评估，以确定它们减少三种根结线虫繁殖的能力： 、3号小种和1号小种。还在温室条件下使用选定的抗性和感病品种评估了线虫的侵入和发育情况。根瘤严重程度、每克鲜根的卵数以及繁殖率因品种对线虫感染的反应而异。油菜萝卜品种卡伍德对 具有抗性，而性格和协和是维持寄主，允许线虫在植物上维持或增加其种群数量。对于 ，对照和卡伍德油菜萝卜以及立吹燕麦是抗性寄主。支持 繁殖很少的品种是性格和卡伍德萝卜以及立吹燕麦。在感染早期，相当数量的线虫进入了油菜萝卜和燕麦的感病和抗性品种的根中。然而，与感病品种相比，抗性品种中从根中计数的幼雌虫和产卵雌虫数量明显减少或受到抑制，这表明抗性发生在感染后阶段。对根瘤组织的组织病理学检查也揭示了选定的油菜萝卜和燕麦品种对这些线虫种类的感病性和抗性反应。油菜萝卜和燕麦是冷季一年生作物，有可能用作“诱捕”或“生物熏蒸”作物，以抑制土壤中的植物寄生线虫。对油菜萝卜品种（卡伍德、红衣主教、决赛、图像、协和、对照、生态免耕、性格和卡纳瓦罗）、白燕麦（立吹）和黑燕麦（普拉泰克斯）进行了评估，以确定它们减少三种根结线虫繁殖的能力： 、3号小种和1号小种。还在温室条件下使用选定的抗性和感病品种评估了线虫的侵入和发育情况。根瘤严重程度、每克鲜根的卵数以及繁殖率因品种对线虫感染的反应而异。油菜萝卜品种卡伍德对 具有抗性，而性格和协和是维持寄主，允许线虫在植物上维持或增加其种群数量。对于 ，对照和卡伍德油菜萝卜以及立吹燕麦是抗性寄主。支持 繁殖很少的品种是性格和卡伍德萝卜以及立吹燕麦。在感染早期，相当数量的线虫进入了油菜萝卜和燕麦的感病和抗性品种的根中。然而，与感病品种相比，抗性品种中从根中计数的幼雌虫和产卵雌虫数量明显减少或受到抑制，这表明抗性发生在感染后阶段。对根瘤组织的组织病理学检查也揭示了选定的油菜萝卜和燕麦品种对这些线虫种类的感病性和抗性反应。
