四川牡丹和块根芍药第五号染色体异常的减数分裂证据  

Meiotic abnormalities of the fifth pair of chromosomes in Paeonia decomposita and P. intermedia

作　　者：王士泉[1,2] 张大明[1] 

机构地区：[1]系统与进化植物学国家重点实验室,中国科学院植物研究所,北京l00093 [2]中国科学院研究生院

出　　处：《植物分类学报》2008年第2期155-162,共8页Acta Phytotaxonomica Sinica

基　　金：国家自然科学基金资助项目(30121003,39870055).

摘　　要：四川牡丹Paeonia decomposita和块根芍药Paeonia intermedia具有共同的第五号染色体减数分裂异常:与长臂相比,短臂在遗传距离和物理距离之间存在巨大的背离。短臂的遗传距离约是长臂的1/28(块根芍药)和1/50(四川牡丹),短臂的物理距离约是长臂的1/3,物理距离是遗传距离的9倍以上。在四川牡丹中,五号染色体的环形二价体(两个臂形成交叉)和棒状二价体(仅一个臂形成交叉)的比率是1.94:98.06,而在块根芍药中是3.42:96.58。在这两个种中,棒状二价体大大多于环形二价体。四川牡丹和块根芍药第五号染色体的后期I倒位桥出现频率非常低,而且断片长度是变化的。This study revealed that there were common meiotic abnormalities on the fifth pair of chromosomes in Paeonia decomposita and P. intermedia. Short arms had a tremendous deviation between genetic distance and physical distance, when compared with the long arms. The genetic distance of the short arm was about a twenty-eighth （P. intermedia） and fiftieth （P. decomposita） of the long arm, whereas the physical distance was about one third of the long arm and the physical distance was over nine times longer than the genetic distance. In P. decomposita, the ratio between ring bivalents （both arms formed chiasma） and rod bivalents （only one arm formed chiasma） was 1.94 ： 98.06, whereas in P. intermedia the ratio was 3.42 ： 96.58. In both of the species, rod bivalents were much more than ring bivalents. Occurrence frequency of anaphase Ⅰ bridges was low in P. decomposita and P. intermedia, and the length of fragments varied in a range.

关 键 词：后期Ⅰ桥 第五号染色体 核型 减数分裂 四川牡丹 块根芍药 

分 类 号：S685.11[农业科学—观赏园艺] S682.11[农业科学—园艺学]