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51.
Cytogenetics of intergeneric hybrids between Brassica species and Orychophragmus violaceus 总被引:3,自引:0,他引:3
In the sexual intergeneric hybrids between the cultivated Brassica species and Orychophragmus violaceus, both complete separation and partial separation of the parental genomes were found to occur during mitosis and meiosis under genetic control. The cytogenetics of these hybrids was species-specific for Brassica parents. The different chromosome behavior of hybrids with three Brassica diploids ( B. campestris , B. nigra and B. oleracea ) might contribute to the different cytogenetics of hybrids with three tetraploids ( B. napus, B. juncea and B. carinata). Owing to the parental genome separation, Brassica homozygous plants and aneuploids with various chromosome constitutions were identifiable in the progenies of these hybrids, which were valuable for the study of the structure and evolution of Brassica genome and for the breeding of Brassica crops. 相似文献
52.
Wenhui Wei Sufeng Zhang Jun Li Lijun Wang Bo Chen Xiaoping Fang Zhuan Wang Lixia Luo 《科学通报(英文版)》2006,51(23):2872-2877
Sterile and semi-fertile F1 plants were obtained by intergeneric sexual hybridization between paternal Brassica oleracea var. alboglabra (genome CC, 2n=18) and maternal Sinapis alba (genome SS, 2n=24), BC1 plants were obtained by backcrossing between paternal B. oleracea and maternal semi-fertile F1 plants. Genomic in situ hybridization (GISH) combined with dual-colour fluorescence in situ hybridization (dcFISH) showed that sterile F1 plants contained 21 chromosomes consisting of one B. oleracea chromosome set and one S. alba chromosome set, belonging to expected hybrids, and semi-fertile F1 plants contained 30 chromosomes consisting of two B. oleracea chromosome sets and one S. alba chromosome set. It is obvious that the semi-fertile F1 plants belong to unexpected hybrids. 1―3 trivalents were detected at meiotic metaphase I of semi-fertile F1 pollen mother cells (PMCs). Different separation ratios of S chromosomes were detected at anaphase I. A monosomic alien addition line (MAAL) was identified by GISH-dcFISH from BC1 plants; it contained 19 chromosomes consisting of 18 C chromosomes and 1 S chromosome. At meiotic metaphase I, 9 divalents from B. oleracea and one univalent from S. alba could be detected. Sometimes, one putative C-S trivalent could also be detected. The achievement of B. oleracea-S. alba monosomic alien addition lines lays a foundation for gene introgression, location and cloning. 相似文献
53.
以7个显性无腺体陆地棉品系和4个常规品种为材料,按NCⅡ设计,对28个组合的F_1及亲本进行了通径分析。结果表明:杂种一代的产量构成与亲本明显不同,其产量构成因素中对皮棉产量贡献的大小依次是单株铃数>铃重>衣分;而亲本中为衣分>铃重>单株铃数。 相似文献
54.
采用溶剂热法在N,N-二甲基甲酰胺溶液中合成了不同摩尔比例的SrCl_2和Bi(NO_3)_3(分别为5%,10%,30%,50%,80%)与对苯二甲酸形成的含Sr~(2+)和Bi~(3+)有机杂化体,并在紫外可见光照射下对其进行了罗丹明B降解活性的评价.结果表明:杂化体在紫外可见光下对RhB降解活性良好,其中SrCl_2摩尔比例10%掺杂的催化剂光降解活性最佳,这归结于其在紫外区域对光有很好的吸收及光生电子和空穴能有效地分离.双金属离子能协同调节有机杂化体的光催化活性. 相似文献
55.
采用不同的聚合方法使苯乙烯进入含双键的酰胺-胺化合物嵌入改性膨润土层间聚合,获得了三种膨润土/聚苯乙烯杂化材料。用XRD、IR、TG、SEM和TEM对其结构进行了表征。SEM测试表明,改性膨润土/苯乙烯的冲击断面形貌比对照的PS有明显的改善,呈现较典型的韧性断裂特征。TEM结果则显示改性膨润土已大部分分散到50nm以下。 相似文献
56.
Summary Species within theD. bipectinata species complex pose problems experimentally because of their morphological similarity. By measuring the number of teeth in each row of the male tarsal sex-comb, an unknown specimen can be allocated to a hybrid or parental group by means of a discriminant function. This paper describes which rows of the sex-comb are the best discriminators for particular comparisons.Acknowledgments. We thank L. Anderson and P. Rowbury for technical and research assistance, Dr I. Bock for providing fly stocks and for his continued interest and helpful discussions, and the Australian Research Grants Scheme for financial assistance. 相似文献
57.
小麦与高冰草体细胞杂种F5代麦谷蛋白及SDS沉降值分析 总被引:10,自引:0,他引:10
通过对普通小麦与高冰草体细胞杂种F5代 175个株系的麦谷蛋白及SDS沉降值分析 ,发现杂种F5代有 10种不同的麦谷蛋白组成 ,并出现了 1Ax1,1Ax2 ,1Bx13,1By16 ,1By8,1Dx5等 6种不存在于亲本小麦中的高分子量麦谷蛋白亚基及 1Bx13 1By16 ,1Bx7 1By8,1Dx5 1Dy12等 3种新亚基组合 ,部分杂种中出现了高冰草的麦谷蛋白特征谱带 ;杂种株系的SDS沉降值表现出较大的差异 ,其中一些杂种的SDS沉降值明显高于亲本普通小麦 .结果表明 ,通过体细胞杂交有可能将野生禾草的优良性状引入普通小麦 ,创造出多种不同组成及组合的新种质 ,为小麦品质育种开辟新途径 相似文献
58.
59.
Jinpeng Yan Xinhong Guo Shaojun Liu Jun Xiao Zhen Liu Yubao Chen Yun Liu 《自然科学进展(英文版)》2009,19(6):693-698
The sequences of the ATPase8/6 genes for the triploid, tetraploid and pentaploid hybrids as well as for their male parent blunt snout bream were determined. In order to examine mitochondrial maternal inheritance, the sequences were subjected to a comparative sequence analysis with the homologous sequences of red crucian carp, their female parent, and zebrafish as the outgroup. Base composition
and variation as well as the divergences based on nucleotide sequences and deduced amino acid sequences were calculated. Phylogenetic trees were also constructed with maximum parsimony (MP), minimum evolution (ME), neighbor joining (NJ) and the unweighted pair group method with arithmetic mean (UPGMA) algorithms in MEGA 3.1. The results showed that most nucleotide substitutions occurred at the third codon position of the two genes and thus represented synonymous mutations. The nucleotide sequence divergences of the ATPase8/6 genes ranged from 0.0% to 21.6% among ingroup samples (three types of polyploids and their parents), and 27.0–28.2% between their ingroup and the outgroup samples. All the polyploids were considerably closer in sequence relationship to the female parent red crucian carp (0.0–3.3%) compared to their male parent blunt snout bream (21.0–21.6%). The phylogenetic trees also showed a similar result. In conclusion, the mitochondrial ATPase8/6 genes of artificial polyploid fish stringently indicated maternal inheritance. Our results also suggested that the ATPase8/6 genes are valuable genetic markers to track genealogies and variations in the progenies of the hybrids. 相似文献
60.
在乙醇-水混合溶剂中采用共沉淀法将非离子型疏水性农药哒螨灵插入镁铝层状双金属氢氧化物(layered double hydroxides,LDHs)层间,制备出哒螨灵-LDHs杂化物。依据哒螨灵分子大小和杂化物的层间通道高度推测,哒螨灵分子是沿长轴方向与层板成一定倾斜角度以单层方式排列于LDHs层间。释放动力学研究表明,释放过程符合准二级动力学方程,LDHs颗粒内扩散是释放控制步骤;哒螨灵-LDHs杂化物具有明显的农药缓释性能,有望成为一种新型农药缓释剂。 相似文献