体细胞杂交技术在马铃薯遗传育种研究中的应用

体细胞杂交技术是打破有性杂交不亲和障碍,将野生种优良性状引入普通栽培种,丰富马铃薯遗传基础,创造新种质的有效手段。本文在原生质体的分离融合、融合体的筛选、杂种的鉴定等方面对马铃薯体细胞杂交技术进行综述的基础上,介绍了近年来马铃薯体细胞杂交技术的研究进展,并就体细胞杂交技术在马铃薯遗传研究育种上的应用进行了阐述。

Cytogenetic comparisons between A and G genomes in Oryza using genomic in situ hybridization

The genomic structures of Oryza sativa （A genome） and O. meyeriana （G genome） were comparatively studied using bicolor genomic in situ hybridization （GISH）. GISH was clearly able to discriminate between the chromosomes of O. sativa and O. meyeriana in the interspecific F1 hybrids without blocking DNA, and co-hybridization was hardly detected. The average mitotic chromosome length of O. meyeriana was found to be 1.69 times that of O. sativa. A comparison of 4,6-diamidino-2-phenylindole staining showed that the chromosomes of O. meyeriana were more extensively labelled, suggesting that the G genome is amplified with more repetitive sequences than the A genome. In interphase nuclei, 9-12 chromocenters were normally detected and nearly all the chromocenters constituted the G genome-specific DNA. More and larger chromocenters formed by chromatin compaction corresponding to the G genome were detected in the hybrid compared with its parents. During pachytene of the F1 hybrid, most chromosomes of A and G did not synapse each other except for 1-2 chromosomes paired at the end of their arms. At meiotic metaphase I, three types of chromosomal associations, i.e.O, sativa-O, sativa （A-A）, O. sativa-O, meyeriana （A-G） and O. meyeriana-O, meyeriana （G-G）, were observed in the F1 hybrid. The A-G chromosome pairing configurations included bivalents and trivalents. The results provided a foundation toward studying genome organization and evolution of O. meyeriana.

我国小麦改良技术取得重要突破

近日，山东省和国家863项目“小麦体细胞杂交技术及其在育种中的应用”，通过了山东省科技厅主持的技术鉴定。其中，利用不对称体细胞杂交技术创建耐盐、抗旱、高产、优质小麦新种质及新品种，是一项重要突破，总体研究达到国际领先水平。