The Studies On The Overcoming Of Standing Bolting And The Key Making Seeds Technology In Strong Winter Parents Of Qingan 80

Braauca oleracea. Var.capitata L. has another names such as Yang cabbage, lianhuacai, cabbage, baoxincai, huizibai, yuanbaicai, datoucai and so on . It belongs to cruciferae plant and origins from Europe Med , North Sea Coastwise and Asia Minor area. The improving of Brassica oleracea wildness seed devolution was first used by Lutetian and Greek. Before B.C 2500—2000 it was planted and it is the longest history and has the biggest areas .Hitherto China has planted for 300 years from 17C 90 ages. Cabbage is one of the most planted vegetables in China. It covered over 850,000h and was the fourth of all the most vegetable variety about the country. In our country the cultivation and application of F1 hybrid variety gets to 100 percents, and it can be cultivated all over the year, moreover the key to the successful cultivativation is to select strong winter variety cabbage variety has another making seeds problem. Cabbage belongs to green vernalization, it is vernalized when the seeding grows certain size and has certain time low temperature .That is to say cabbage must has three conditions: first it has certain size seeding;second has vernalization temperature and third has some days under the above temperature. Qingan 80 is selected by College of Horticulture Sciences Northwest A&F University, it is a strong winter variety to adapt to living through the winter and early spring, its most important characteristic performance comes from parents: that is low temperature resistance, standing weakened light and resisting bolting. The studies on the experient is to select half-plant F1 hybrid production form and use nature low temperature to vernalization the seeding. According to analyse vernalization condition of the Qingan 80, using different seeding period and GA3 density to deal with it in order to find strong winter parent that can stand bolting measure. Meanwhile we study the technology of making seed according to deal with parent seeding period, density, fertilizer application, hormone, remove polt,. The experient results shaved:(1) Qingan 80 parent is very strictly about vernalization condition. Male FT6358-3-3 is sowing on 2d September, it has 18 leaves, . Stem is about 1.3cm, bolting percent is over 98 when the seedling vernalization. Female parent B2523-3-2 is sowing on 12th, September the lowest leaves 21.8, stem 0.8 and bolting percent is the same as the male parent.(2) we use half-plant outdoor wintering to produce Qingan 80 F1 hybrid male parent 2nd September, female 12th September are the best seeding period. Parents vernalization bolting percent come to above 98;the best field planting desity is 3600 per 667m2 hybrid purity is over 98 percent.(3) The adapt fertilizer N:20 kg, P:8 kg, K:28 kg per 667m2 all the P, K fertilizer must apply fertilizer the subsoil. N according to base manure: seeding fertilizer: bud fertilizer = 1:1:1 to fertilize.(4) The adapt desity about male parent is 300mg/L GA3, in March continue 3 to deal with plant apical meristem that can make parent first bloom 3-4d ahead of time.