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Hybridization to some extent broke the boundaries between species, different species of human promotion and exchange of genetic introgression, is advantageous traits into the target material to obtain an effective way of new species, is the introduction of foreign genes, creating variation more methods. By means of such breeding, has a large number of excellent or specific genes from wild species or related genera, species into cultivated species, to create new germplasm resources. Onion' dissertation">Onion (Allium fistulosum L.) and onion (Allium cepa L.) is the same Liliaceae Allium biennial herbs. Carbohydrates and calories than green onions onion, and protein, fat, and various water-soluble vitamin content were significantly higher than onions. Onion with disease-resistant, resistant storage of dry matter, soluble solids, high carbohydrate traits is excellent material for improved onion germplasm. In this study, through the use of green onions, onion with a different skin color male sterility onions, green onions for reciprocal crosses, get different parental combinations distant hybridization F 1 generation rate statistics by performing pollination, pollen grain observation, investigation and quality traits botanical traits analyzed preliminarily discussed with onion scallion hybridization affinity. The main results are as follows: 1. Onion, onion pollination between the use of different methods of distant hybridization pollination, seed set rate varied. The use of spatial isolation pollination average seed, seed rate is highest, followed by bee pollination stick, brush pollination minimum. Crosses between different to the average seed onions scallions × the highest rate of spatial segregation pollination rate of 50.15%; same conditions, its anti-crosses onion scallion average seed rate × 17.9% in male sterile line description for the mother The more accessible hybrids. Distant hybrids germination is low, an average of 68.5%, the germination rate of 79%, showing that distant hybrids vitality is low. 2 green onions, onion distant hybridization F 1 -generation plant vegetative normal growth and development, plant morphology, phenology period ranging between parents present, is more interested in the female parent, there is a greater part of the plant morphological variation, significant heterosis. Hybridization F 1 -generation plants appear sheath basal varying degrees of thickening, swelling, skin color between the two parents is formed between the long ball bulb, smaller, with an average bulb 8.17cm, transverse Stems 5.59cm, bulb weight 178.28g. 3. Distant hybridization F 1 -generation highly sterile, onions ms × onions F 1 -generation plants sterile plants averaged 68.8%, male sterility type to type Ⅰ based; onion ms × onions F 1 -generation plants sterile plants was 100%, Ⅰ type male sterile 94%. Hybridization F 1 -generation low pollen viability, with an average 11.3% pollen viability, viable pollen parent only about 10%. Scanning electron microscope, the distant hybrids pollen folds flat, irregular shape, surface ornamentation obvious difference between the parental characteristics. 4 green onions, onion distant hybridization F 1 generation of different growth period, the false stem / bulb nutrient content and the main trends there are differences with the parent. Hybridization F 1 Generation soluble sugar content ranged between two parents; soluble protein content is higher initially, with the gradual decline in plant growth, with the parent first and then decreased trends vary greatly ; ascorbic acid content and trend remained consistent with the parent; free amino acid content is closer to the parent with onion, green onions is much higher than the parent. Hybridization F 1 -generation volatile components to sulfur compounds mainly include esters, hydrocarbons and other compounds, in which the flavor of Allium crops have a greater contribution to dipropyl sulfide, a sporadic spicy onion and garlic aroma substances, distant hybridization F 1 generation of two-propyl disulfide average content of 33.75%, exceeding the parent content 11.4 1 9.3%, spicy rich flavor.
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