【作者】 祝海燕；

【导师】 张成合；

【作者基本信息】 河北农业大学 ， 蔬菜学， 2005， 硕士

【摘要】 本文以结球甘蓝(2n=2x=18)及其同源三倍体(2n=3x=27)为试材,通过形态特征观察和细胞学鉴定等手段,从三倍体与二倍体的回交子代中,初步分离、鉴定出了一整套初级三体材料(Tr-1～Tri-9),并对各三体植株的特征、特性以及n+1雌、雄配子的传递率进行了观察研究,主要结果如下: 1.对结球甘蓝减数分裂观察和染色体核型分析表明,二倍体结球甘蓝(CK)有两个染色体组,染色体基数n=x=9,核型公式为2n=2x=18=8m+10sm(2SAT),以此为参照,从3x×2x的61个2n+1试管株系中,初步鉴定出了一整套初级三体。其中,1号初级三体3个、2号初级三体2个、3号初级三体5个、4号初级三体2个、5号初级三体3个、6号初级三体1个、7号初级三体6个、8号初级三体2个、9号初级三体3个,分别占鉴定植株总数的4.92%、3.28%、8.19%、3.28%、4.92%、1.64%、9.84%、3.28%和4.92%。 2.各初级三体间及其与2n亲本之间,在形态特征或生长特性上均表现出不同成度的差异。如,1号三体,花枝细长而直立;2号三体,株型松散、花枝节间长而弯曲;3号三体,花柱很长、明显高出花药、花药空瘪;4号三体,花蕾四棱形、花瓣内卷;5号三体,花枝多而细弱;6号三体,植株矮小、二级叶脉不明显;7号三体,花枝少而粗壮,花蕾略呈紫色;8号三体,植株高大健壮,开花期晚;9号三体,叶细小、开花早而集中。这些表征差异可作为识别各三体的参考依据。 3.各初级三体以三价体(Ⅲ)为主要联会形式,后期Ⅰ三价体多呈2/1分离,极少见有落后染色体遗失在细胞质中的情况。因此,后期Ⅰ呈10/9分离的细胞占绝大多数。 4.各初级三体的花粉生活力、花粉整齐度、花粉量/花药,均低于二倍体,但不同三体之间存在着明显差异。花粉生活力与结籽率之间表现出一定程度的正相关性,但花粉整齐度、花粉生活力、n+1雄配子的传递率三者间无明显的相关关系。 5.不同初级三体的额外染色体通过花粉和胚囊的传递率不同;Tri-1、Tri-2、Tri-3、Tri-4、Tri-5、Tri-6、Tri-7、Tri-8和Tri-9通过雌配子的传递率分别为15.38%、12.50%、12.50%、46.15%、22.22%、3.70%、2.70%、42.31%、9.09%;通过雄配子的传递率分别为12.00%、12.20%、7.69%、4.76%、9.09%、11.11%、0%、0%、13.33%。更多还原

【Abstract】 The inbred lines of diploid and triploid of the head cabbage (zhonggan-11) were used as materials for selecting primary trisomics of cabbage in this paper. By cytological identification and karyotype analysis, a set of primary trisomics (Tri-1~ Tri-9) of the cabbage was selected from progenies of the triploid crossed with the diploid parents. The plant morphological characteristics, meiosis behavior, pollen characters, seed setting, transmission frequency of n+1 female gametes and n+1 male gametes of the different trisomics were observed or studied. Conclusions were as followed:1. Karyotype analysis showed that the karyotype of the normal diploid cabbage (CK) was 2n=2x=18=8m+10sm(2SAT). And with the karyotype of the diploid cabbage as contract, by cytological and morphological identification and karyotype analysis , a whole set of trisomics (Tri-1 ~Tri-9 ) of the cabbage was selected from the 61 2n+l plant clones of 3xx2x, in which the 3 plant clones was Tri-1, 2 clones was tri-2, 5 clones was tri-3, 2 clones was tri-4, 3 clones was tri-5, 1 clones was tri-6, 6 clones was tri-7, 2 clones was tri-8, 3 clones was tri-9, and the rate was 4.92%, 3.28%, 8.19%, 3.28%, 4.92%, 1.64%, 9.84%, 3.28%, 4.92% respectively.2.Some difference in morphological or developmental characters existed between the diploid and the trisomics or among the different trilomics. Such as, Tri-1 with more strong ramification ability, and the flower branches slightness and erection; Tri-2 with incompact plant shape, curly flower branches, and longer branch and knote;Tri-3 with longer style, the anthers bellow the style obviously, the anther empty and shriveled; Tri-4 with four ridge flower buds, longer flower stalk and volute petal; Tri-5 with slighter and curved branches; Tri-6 with dwarf and compact plant shape and sub-veins indistinctly; Tri-7 with high and strong plant shape, late anthesis, bigger and round flower buds; Tri-8 with fewer and thick branches, and the flower buds showing a little purple; Tri-9 with small and thin leaves, and the anthesis showing earlier and relatively simultaneous. 3. Trivalent (III ) was the primary synapses form for the three homologues更多还原