Analysis Of Main Agronomic And Molecular Cytogenetic Traits Of New Strains Of Potato

As one of the main food crop, potato has rich nutrition, and is known as the "underground apple" laudatory name. In recent years, with the rapid development of potato processing industry such as starch, french fries, chips and granules in China, the demand for potato varieties with different processing purpose increases significantly. However, the special potato varieties that meet the above requirements of processingin our country are less at present. In order to cultivate new potato varieties which are fit for growing and processing in Inner Mongolia, according to the parents matching principle of large difference of genetic background and ecotype, and trait complementary, we use potato ’H-027’introduced form United States with good commodity performance as female parent, and domestic potato’Longshu6’and’Longshu7’which has strong adaptability, high late blight and black scurf resistance as male parent, obtained four excellent new strains, A2, A10, Bland B12, from two hybrid F1 combinations’H-027’×’Longshu6’and’H-027’ x’Longshu7’, by artificial pollination, cross and careful individual selection of hybrid progenies.On the basis of the previous research, this study focuses on analysis and evaluation of main agronomic traits, chromosome pairing configuration and pollen ferti of 4 new strains, and builds the SSR fingerprint of four new strains and their parents,in order tolay the foundation for breeding and utilizing excellent new strains of special potato The main results are as follows:1. The average plant height of four new strains A2, A10, B1 and B12 was 87.72 cm 72.20 cm,55.62 cm and 49.34 cm, respectively. The strain B12 was mid-early matunn and has high starch, the strains A2 and A10 were mid-maturing and suitable for granule processing, and the strain B1 was mid-maturing and french fries processing type. The fou new strainsh as good tuber shape, eye shallow, tidy and concentrated tuber, of which the average yield is more than 1 kg and the commodity potato rateis above 85%.2. The main stalk number has a significantly positive correlation with branch numb and tuber number per plant; the tuber number per plant has a significantly positive correlation with reducing sugar content; the yield per plant has a significantly positive correlation with the average tuber weight, dry matter content, starch and protein content the average tuber weight has a significantly positive correlation with dry matter content; and there is a extremely significantly positive correlation between dry matter content and starch content.3. The chromosome pairing configuration of strain A2, A10, B1, B12 were 9.97 Ⅰ+7.54Ⅱ+2.96Ⅲ+3.52IV,8.31 Ⅰ+9.08Ⅱ+3.43Ⅲ+2.81Ⅳ,5.45 Ⅰ+12.98Ⅱ+2.41Ⅲ+ 2.34Ⅳ and 3.66 Ⅰ+14.80Ⅱ+1.99Ⅲ+2.19Ⅳ, respectively.4. The fertile pollen rates of new strains A2 and A10 are low, at 18.02% and 23.85% respectively, which are suitable as female parent. The fertile pollen rates of new strains Bl and B12 are high, at 57.83% and 69.86%, respectively, which are suitable as male parent.5. Using 10 SSR suitable primers to amplify genome DNA of 7 potato materials, total of 142 clear and stable SSR polymorphic bands were detected, and the polymorphic rate was 81.69%. A SSR fingerprint map was established, which could distinguish fou excellent new strains and their parents. The genetic distance (GD) of four new strains anc their parents ranged from 0.2298 to 0.6508. Based on the GD value of 0.34, seven potatc materials were classified into three categories:the new strain A2, A10 and’H-027’as a category; B1, B12 and’Longshu7’as a category; and’Longshu6’as separate category.