The Cytogenetics Studies On The Hybrid Progenies Between Hordeum And Triticum

The wheat is the second leading crop in our country, and the wheat production possesses the important economic position in the national economy development. The first assignment of development wheat production is raising yield per unit area and improving quality, and the varieties improvement can not do well without innovation of new wheat germplasm. The distant hybridization can reap the excellent wheat germplasm with the genes from the relative species and genus of Triticum, and makes the wheat breed modification gain breakthrough, thus can constantly raise the wheat production standard.Barley has many profitable properties, such as early-maturity, resistance to ear sprouts, resistance to yellow dwarf, high content of lysine, poly-flowery and poly-grain, suitable for late sowing, etc. If these profitable properties are introduced into common wheat, it wills posses the important meaning to enrich wheat germplasm and improve the wheat breeding level.The hybridization between Hordeum and Triticum has been carried frist by Willim farrer in 1896. Afterwards Kruse had successfully gained the hybrids between T.aestivum and H.vulgar, and Islam had cultivated six aline addition lines of Triticum- Hordeum. More than 100 years, many researchers of home and abroad carried on extensive research at hybridization between common wheat and barley. On the base of the hybrids, the later scholars obtained some alien addition lines, alien substitution lines and alien translocation lines. In order to suit horizontally raises of the wheat production, researchers needs constantly to create new germplasm, and to carry on cytogenetics research on the hybrid generation, and at the same time, to breed the new varieties using this new germplasm with barley excellent characters.This research was carried on the work foundation of wheat-barley hybridizing and backcross progeny of Professor Li zhang, and this paper will studies on the cytogenetics of the hybrid generation between Hordeum and Triticum. Firstly we will select some alien additional lines with steady heredity, and analysis the self hybrids generations' chromosome divided action from the backcross progeny produced by the alien additional line. Secondly some alien substitution lines will be created by use of the methods Nullisomic Backcrossing, and some translocation lines will be selected by observing the agronomy character, resistance to disease, and its quality appraisal of these wheat-barley materials.The main results of this experiment are as follows: 1) Two disomic alien addition lines (2n=44) WB9516 and WB9589 that its heredity was relatively stable and some monosomic alienaddition lines (2n=43) were selected from the hybrid progenies between wheat and barley. The segregation frequency of disomic addition plant (2n=44=22 II ) and monosomic addition plant(2n=43=21 II+1 I ) in selfing generation of the monosomic addition line (2n=43) was low, only 1.2% and 25.6%. But the segregation frequency of monosomic and disomic addition plant in the disomic addition line (2n=44) was high, it was 29.9% and 56.9%. That is to say, the transmission rate of the added chromosomes in disomic addition line was obviously higher than that of the monosomic addition line in their selfing generation. It showing disomic addition line was relatively liable to preserve. 2) Two heredity steady wheat-barley substitution lines WB0215> WB02126 were cultivated by the means of nullisomic backcrossing method using the two disomic addition lines WB9516 and WB9589. 3) Through observing the morphologic marker, resistance to disease, and other characters in the field, seven types middle materials with barley excellent character were selected, and two of these materials WB371 and WB375, which includes the stable character of wheat-barley and were directly selected from the selfing generation in the alien addition lines and substitution lines, were better than the other. One of them, WB371 was higher production in the experiment. Using early-maturity middle material of wheat-barley as female and crossing with Shan 229, the new strains WB158 was cultivated by combining the convention breeding. This strain has early-earring character of barley and main excellent agronomy characters of Shan 229.