Analysis Of Main Characters On The Interspecific Hybridization F₁ Between Welsh Onion And Onion

The wide hybridization can break limits of species in some extent, promote genetic introgression and communication of different species, which are effective approaches to transfer useful characters to cultivated crops, to produce new species, to introduce alien gene and create variations. At present by this breeding method, a lot of important and special genes have been transferred to cultivar from wide relatives, cerating new germplasm resources.Welsh onion (Allium fistulosum L.) and onion (Allium cepa L.) were liliaceous, of Allium biennial herb. carbohydrates and calories in the welsh onion low than the Onion, And protein, fat and all kinds of water-soluble vitamin content was significantly higher than the onion. The onion with strong disease resistance and storage , dry matter, soluble solids, carbohydrate content were higher, is the fine material improved welsh onion germplasm. This research through the use of male sterile welsh onions with different light Onions for positive hybrid, obtained different parents combinations of interspecific hybridization F₁ plants. Through setting pollinate fertility statistics, pollen grains observation, botany properties investigation and analysis of quality traits, preliminary discussion the compatibility of interspecific hybridization between welsh onion and onion. The main results were as follows:1. Welsh onion and onion using different methods for pollination interspecific hybridization were different in Seed fertility and capsule rate . Using the method of have the highest rate in average and capsule rate, bees knots, bees pollinate law secondly, brush pollination method lowest. Between different parents combinations, welsh onion×onion have highest seed fertility rate, spatial segregation pollination seed fertility rate reached 50.15%, under the same conditions, the onion×welsh onion on average only 17.9 %, Explain to welsh onion male sterility plants for female are easier obtained hybrid. Seed germination viability of interspecific hybrids were low, average 68.5%, seed germination reached 79%, visible interspecific hybrids vigor is relatively low.2. Welsh onion and onion interspecific hybridization F₁ plants trophosome growth normal. Plant botanical characters and phenology basic between parents, but more female. Part of plant form have large variation, heterosis is obvious. interspecific hybridization F₁ plants base of leaf have varying degrees of appeared thickened, swollen, colouring between parents and formed long spherical bulbs, Small volume, bulb high average 8.17 cm, stem horizontal average 5.59 cm, bulb weight 178.28 g .3. Interspecific hybridization F₁ plants were highly infertility, ms-onion×welsh onion F₁ generation plants male sterility rate average 68.8% , male sterility mainly inâ… type; ms-welsh onion×onion F₁ generation plants male sterility rate reached 100%, 94% were male sterility mainly inâ… type. Interspecific hybridization F₁ pollen energy were low and average pollen vigor for 11.3% , there were only 10% of the vigor pollen of parents. In scanning electron microscope, interspecific hybrids pollen grains folds flat and irregular shape, surface decoration feature differences with their parents.4. Welsh onion and onion interspecific hybridization F₁ plants in different growth period, cauloid/bulb in the main nutrient content and trend were different with their parents. Interspecific hybridization F₁ soluble sugar content between two parents; soluble protein content highly in the early time, with the plant grows gradually decreases, hybrids bigger difference with the parents First rising then decreased of the change trend; ascorbic acid content and the trend were maintain consistent with parents; The free amino acid were relatively close with onion and far above the welsh onion. Interspecific hybridization F₁ plants volatile organic compounds mainly contains sulphur, and including esters, alkane etc. Which flavor of allium plants, to have great contributions of dipropyl disulfide, is a pungent onion and garlic out aroma of material, Interspecific hybridization F₁ plants dipropyl disulfide average content of analysis reached 33.75%, beyond the parents 11.4 19.3% levels, taste spicy.