Study On Directional Transfer Of Genetic Male Sterile Line In Milk Chinese Cabbage

In order to resolving the problem that cross breeding in utilizing hybrid vigor by usingthe material of Multiple Allele inheritance green stalk cabbage as the source of the multiplealleles of male sterility, the experiment was designed to be the compound transfer anddirectional transfer scheme in studying on the method of Genetic male sterility(GMS) lines ofmilk Chinese cabbage. The transfer effect was analyzed and compared.The main results wereas follows:1. Sexual hybridization was employed in identifying genotypes of the fertile target lineAI023 of milk Chinese cabbage with Genetic male sterility (GMS) line of green stalk cabbage00S107 as test cross-line. The results indicated that the genotype of male fertile line AI023 ofmilk Chinese cabbage on Multiple Allele position of GMS is purified-dominant male restorergenotype "Ms~fMs~f".2. Compound transfer scheme was designed to transfer the GMS gene from male sterileline 00S107 into milk Chinese cabbage AI023, A new GMS line A1, its corresponding ABlines typeâ… and temporary maintainer lines which not noly with 100% rate of sterility plantsand 100% degree of sterility flowers,but also with genetic basis of the fertile line AI023 wereobtained.3. Directional transfer scheme I was put forward for the purpose of transferring themultiple allele from 00S 107 to the selected male fertile lines of milk Chinese cabbage whichgenotype is "Ms~fMs~f"and breeding GMS lines which had stable inheritance and similar to themale fertile lines in botany and economic characters. Three new GMS lines A2,A3,A4 with100% degree of sterile plants and sterile flowers which separately belonged to BC1,BC2,BC3 were obtained.4. The GMS lines A1,A2,A3,A4 which come from compound and directional transferscheme and the fertile target line AI023 were used as materials to analysis the effect of thetwo transfer scheme.The results showed that the horticultural characters of GMS line A1which come from compound transfer scheme were between 00S107 and AI023.Thehorticultural characters of GMS line A4 which come from directional three backcrossgenerations transfer were similar to AI023, that accomplished the transfer of GMS gene,botany and economic characters at the same time.5. Cross combinations were made by using the transferred GMS lines A1,A2,A3,A4as female and 3 self-lines of different genotypes as male,these carried out the experiment tocomparing the varieties. With the increasing of directional backcrossing generationstransferred, variation coefficient and uniformity degree of different hybrid groupsdecreasing.Depanding on the analyzing results of the uniformity degree,combining ability,disease resistance ability and quality, we select 3 excellent cross combinations of milk Chinese cabbage C4,C8,C12.