Studies On Germplasm In Melon (Cucumis Melo L.) Drought Resistance

Melon (Cucumis melo L.) is one of important vegetable. During dry seasons, droughtstress existed and severely influenced the melon production in dry or half dry areas. In thisexperiment, some melon cultivars of different ecotype were seIected and studied inmorphological, inter-structural, physiological and biochemical changes that occurred duringtheir seed germinating, seedling and adult stages under drought stress. The correlation ofdrought resistance among the different growing stages of the melons, and the appraisedindexs, and selecting methods for searching germplasm resource with drought resistance werestudied.The germination percentage and germination stress index of the melons decreased underwater stress. The performance of the melons under water stress during seedling stage were theincrease of the root length, the root fibril amount and the R/T ratio; and were the significantchanges of physiological and biochemical index. The melon under water stress in flower stageperformed the decrease of the single fruit weight, and decrease of the fruit bearing percentage,and the differences of the physiological and biochemical index.The correlation of the drought resistance of the melons existed among different growthstages. Water saturate deficit (WSD) in seedling stage can be used as the appraised index onthe drought resistance of all the melon germplasm resource. The regression equation wasstimulated to estimate the drought resistance of in the different cultivars. The correlationbetween the amount of irrigating water and the average single fruit weight performed asignicant level, and a regression equation was obtained to stimulate simply the betterirrigation requiremaent of melon.ln this experiment, there drought resistance melon cultivars were selected: Y82-3, 96-88,96-63;and six reIativeIy drought resistance cultivars: 96-56, Gexingchaoren, 36-9-5, HongyanNo.7, Wanglongbai, Jinong998; Y82-3, 96-88 and 96-53 were pellicle ecotype cultivars.