Identification Of The Hybrid Derivatives Between Chinese Cabbage And Head Cabbage

In order to create the alien addition lines,the BC₁ plants which come from the backcrosse between the Chinese cabbage-cabbage allotriploid(ACC,2n=3x=28)back to Chinese cabbage diploid and their selfing progenies BC₁F₂ were used as studying materials.4 monosomic addition lines,1 trisomic and 3 double monosomic addition lines were obtained by routine planishing technique,karyotype analysis and SSR.Their morphologic,cytologic and reproductive characters were studied.This study will provid the theory basic for creating alien substitution and translocation lines of Chinese cabbage and cabbage,help to carry out the genetic improvement Chinese cabbage,explore the relation between A and C genomes,study gene intactions,location and expression.The results are listed as follows:1.The chromosome number of BC₁ and BC₁F₂ plants was indentified by counting chromosomes at mitosis metaphase.The rate of 23～26,21 and 22 chromosomes was 72.06%,2.94%and 5.89%respectively identified from BC₁ plants.The rate of 20～22,21 and 22 chromosomes was 61.54%,23.08%and 7.69%respectively identified from BC₁F₂ plants.Thus it could get monosomic addition lines from BC₁ and BC₁F₂.2.Four monosomic addition lines with cabbage chromosome No.1(AA+C_1â…¡),No.2 (AA+C_2â…¢),No.4(AA+C_4â…¡)and(AA+C_4â…¢),a Triplo-6 in Chinese cabbage were identified from BC₁ and BC₁F2 by karyotype and SSR analysis.Three double monosomic addition lines with cabbage chromosomes No.2 and No.7,No.4 and No.7,No.3 and No.5 were identified from BC₁ by karyotype analysis.3.The pollen-mother-cell's meiotic chromosome behavior of plants with 21 and 22 chromosomes showed that:(1)PMC meiosis of the plants with 21 chromosomes may be classed two types.One type was add a cabbage chromosome,the chromosome configurations at diakinesis were mainly showed 10â…¡+â… ;another one type was added one Chinese cabbage chromosome,the chromosome configurations at diakinesis were mainly 9â…¡+â…¢.(2)To the plants with 22 chromosomes,chromosome configurations at diakinesis were mainly 10â…¡+â… +â… .The random separation of 2 univalents led to complex forms of chromosome separation at anaphase. 4.The field character of the four monosomic addition lines and three double monosomic addition lines with cabbage chromosome plants,such as leaf surface character,leaf color, leaf wax,floral organs and so on,were similar to cabbage.The added different cabbage chromosome resulfed in different morphological features.