Evaluation Of 49 Accessions Of Sweet Potato Germplasm In Hainan Island

Sweet potato production been ranked seventh in several major crops in the world. And been ranked fourth in China, just less than rice, wheat and maize.The status of sweet potato have an important position in the national economy, is a very important crop in food, feed, energy, process. The tuber of purple sweet potato contains a lot of anthocyanins,the anthocyanins is possessed of a variety of physiological functions, just as preventing tumors and cancer, preventing cardiovascular disease, etc.. There are good prospects in extracting natural pigment, freshing and health care,processing of functional foods,and so on.The tuber of orange or yellow sweet potato contains many ofβ-carotene.High carotenoid potato better than many same type of fruits and vegetables,there is effect of prevent vitamin A deficiency, eliminate the body of harmful substances,anti-aging,etc.But the purple sweet potato and orange or yellow sweet potato, its value is late to found, its resources is less, these hindered the development of research and exploitation.This paper identified the purple sweet potato and orange or yellow sweet potato's morphology and main characters as yield etc.;evaluated the quality of different cooked tuber, discussed the impact of the quality of internal factors cooked tuber; determined of the three harvest tuber's nutritional composition, exploration the yield and the tuber nutrient changes of the different harvest.And analysee the genetic diversity of 49 accessions of germplasm, Clarify its genetic relationship。The results showed that:1,The results of morphological observation:the purple sweet potato and orange or yellow sweet potato's morphology sush as color of leaf, leaf size, pigmentation of basic leaf vein, pigmentation of basic petionle, petionle color, color of vine, plant type, storage root formation, storage root shape etc.These are similar to ordinary potato. The yield of most of the germplasm is low, especially at the purple sweet potato, it need improve in the future. There are some differents in the purple sweet potato:the germplasm have all the the vine tip pubesence, most the shape of leaf is not the deep of leaf split, the skin color of storage root is purple, only have two color, purple and white, the length of the vine is very long, the resistance to scab is strong. These is different orange or yellow sweet potato. when the top leaf evolving to the stability leaf, the trend of the leaf color is:a variety of colors→green-based, and the trend of the leaf shape is:absent deep split→split→with teeth→no teeth, and the trend of the leaf pubescence is much→few→absent. As the germplasm are different, the degree of change are not the same.2,There are 7 accessions of germplasm which good at comprehensive evaluation, and only B16 (Luodinglianzhou3) of them are collected from the local field. The germplasm which are eating type are A16(Zhanshu 03-40), A25(Guangshu104) and B23(Quanshu76). The germplasm which are suitable for processing starch is B12 (Guifenl) and B23(Quanshu76). The germplasm of high anthocyanin are A13 (Xu 13-4), A16(Zhanshu 03-40), A17 (Xuzil),A25(Guangshu104). The germplasm of high p-carotene is B16 (Luodinglianzhou3). There are dual-use value and are recommended by A16(Zhanshu 03-40), A25(Guangshu104) and B23(Quanshu76) in the germplasm.3,The three harvest period which after being planted 95 days,115 days,135 days, The trend in most of the test shares of tuber yield, dry matter yield, anthocyanin yield, soluble sugar are rise. But the trend of the crude protein content of fresh samples are down.4,The genetic diversity. totally 49 individuals were selected and analyzed by amplifications using 17 ISSR primers screened, each primer produced 4-14 bands, and the average 7.94 and 154 polymorphic bands were generated, of which 135 were polymorphic. The average percentage of polymorphic bands is 87.66%. The same primers have different polymorphic bands amplified among various species, which reflects the polymorphism between various species. The range of genetic identifity coefficient is 0.58-0.93, in the genetic similarity coefficient of 0.70 with 49 germplasm can be divided into 4 categories. The orange or yellow sweet potato together, and meet other purple sweet potato. This shows that between these materials similar genetic background, some of germplasm with high genetic similarity, but the overall mutual Also there are some differences.