臺灣十字花科蔬菜黃葉病菌特性之研究

Abstract

近年來本省各地十字花科蔬菜，逐漸被黃葉病危害且有蔓延的趨勢，嚴重者甚至已達廢耕地步。自蘿蔔、芥菜、芥藍病株分離出之病菌FOR0611、F0M0227、FOK1105各菌株，經接種＋六種＋字夜科作物，發現FOM0227、F0K1105寄主範圍較FOR0611為廣，幾乎可感染各種十字花科蔬菜。三菌株對其寄主均有強而專一致病力。其生理、生化特性彼此間亦有差異，尤其蛋白質種類含量，經垂直平板電泳法分析，F0R0611之蛋白質帶與FOM0227、FOK1105者相異；但與來自西柏林蘿蔔黃葉病菌株(G62045)蛋白質帶相似。因此可確定臺灣十字花科黃葉病至少有兩種菌系，即為Fusarium oxysporum f. sp. raphani（或F. oxysporum f. sp. conglutinans race 2）和F. oxysporum f. sp. conglutinans（或F. oxysPorum f. sp. con glutinans race 1）。 Fusarium. oxysporum (Schi.) Snyder et Hansen, the causal organism of cruciferae yellows, was readily isolated from discolored vascular tissue of radish (isolate FOR0611), Mustard (isolate FOM027), and Kale (isolate FOK1105). Artificial inoculations to sixteen kinds of cruciferous vegetables with infested soil in greenhouse indicated that host range of F0M0227 and F0K1105 were wider than that of FOR0611., but each isolate showed a highly specific pathogenicity on its own host. This is indicative that physiological or pathological specialization already existed in F. oxysporum (Schi.) attacking cruciferous vegetables in Taiwan. Physiological and biochemical studies also showed that growth of F0M0227 and FOK1105 were different from FOR0611 in temperature, carbon and nitrogen source. Soluble protein pattern of radish isolates (FOR) was different from that of F0M0227 and F0M1105 in vertical slab gel electrophoresis, but was almost identical to G6205, an isolate of radish yellows from West Germary. Frorn above studies we could assume that at least two biological (or physiological) forms existed under F. oxysporurn attacking cruciferous vegetables in Taiwan. They were F. oxysporuni . sp. conglutinans (or F. oxysporum . sp. conglutinans race 1) and F. oxysporum f. sp. raphani (or F. oxysporum f. sp. conglutinans race 2).