小麦离体叶段鉴定白粉病抗性方法的研究

STUDIES ON THE DETACHED-LEAF METHOD FOR TESTING RESISTANCE OF WHEAT TO POWERY MILDEW (ERYSIPHE GRAMINIS TRITICI)

1990年4月至1994年4月对小麦离体叶段鉴定白粉病抗性方法进行了研究。结果表明:①在灭菌条件下,以在培养皿中垫两层滤纸,用6BA作保绿剂,置空调室进行鉴定效果较好。②保绿剂的浓度低,发病快、退绿早,反之发病慢、退绿晚。其最适浓度是:苗期6BA为60—100ppm、苯(口并)咪唑为60ppm;成株期6BA以80—150ppm为佳。③从发病快、退绿迟的角度出发,鉴定材料以株龄小、叶龄短的初展叶最佳。④幼苗离体叶段鉴定与幼苗常规鉴定结果基本一致。文中还对大田植株在离体叶段鉴定过程中易变黄的问题进行了探讨。

The detached-leaf method for testing resistance of wheat to powdery mildew was studied during 1990 - 1994. Results indicated that; (l)Under sterilized conditions, using 2 layers of filter paper in petri dishes containing 6BA(6-benzyl aminopurine)as the greenness preservative and conduction of tests under air-conditional room brought the best results. (2) With lower concentrition of greenness preservatives, the development of powdery mildew was faster, as well as yellowing of the leaf-segments was earlier; whereas the higher concentration could keep the greenness of leaf-segments longer and made the development of symptoms slower. The optimum concentrations for the different preservatives are;on seedling leaves, 60-100ppm of 6BA or 40-60ppm of benzimi-dazole; on adult plant leaves, 80 - 150ppm 6BA. (3) Younger leaves collected from seedlings gave better results than those from adult plants. (4)Results of evaluation for powdery mildew resistance by detached-leaf method were fundamentally the same as those obtained from conventional seedling test method.