Determination on Resistance of Sweetpotato XiangShu 75-55 and Its Productivity

Sweetpotato variety, Xiangshu 75-55 is a hybrid progeny from "Xindazhi" and Hebei 69-419 combination.It was bred by The Crop Research Institute, Hunan Academy of Agricultural Sciences in 1974, and introduced by Plant Protection Institute, FAAS in 1978.This variety gradually became a new cultivar after the identification, demonstration and continuous purification and rejuvenation for more than ten years.It characters high resistance to blast, stem rot, and scab diseases, high yield, good quality and long storage periord.After indoor, plot tests and large-area demonstration at different sites for several years, it showed that, Xiangshu 75-55 has stronger blast-resistant capacity than other blaSt-resistant varieties, "329" and "Huabei 48".In disease-epidemic area, its productivity was 25.07% 41.44 % and 2.3 times higher than 329, Huabei 48 and "Xinzhonghua" respectively.In disease-free area, the multi-site determination showed its productivity was 7.67 % ～7.59 % and 10.8 % ～21.3 % higher than 329 and Xinzhonghua.In 1992, the growing area of Xianghu 75-55 reached 0.65 million Mu more.The accumulated popularied-area in 1986-1992 was over 1.7 million Mu.Xiangshu 75-55 has been assigned as a new disease-resistant variety in Fujian province after the examination and approvement by "Fujian Comittee for Crop Seeds Evaluation".