栽培稻×大颖野生稻F_2多倍现象的细胞遗传学研究  

Study on Cytogenetics of the Polyploidy in O. sativa × O. grandiglumis F_2 Plants

作　　者：李子先[1] 刘刚[1] 韩思怀[1] 陈学良[1] 

机构地区：[1]中国科学院成都生物研究所,四川成都610041

出　　处：《遗传》1996年第5期11-15,共5页Hereditas（Beijing)

基　　金：国家自然科学基金;四川省应用基础资助

摘　　要：A栽培精（Oryzasativa）×大颖野生稻（Oryzagrandislumis）F_2经细胞学鉴定为2n＝4x＝48，即已由杂种F_1的ACD异源三倍体变成了异源四倍体。研究了从粗线或到本期Ⅱ的染色体行为，结果表明，F_2的染色体构型为异源节段异段类型，且异常染色体频率极高，合计为87．13％．各类异常染色体频率变化按比例大小依次为：单价体，染色体拖曳，落后染色体，多价体，邻接型易位，不均等分离，桥，不分离和松散配对等、邻接型易位是本研究的中心论题。因邻接型易位的存在是F_2花粉不育的一个重要原因，也是产生节段异段染色体构型的重要原因；因邻接型易位带来相互易位，可供有种利用．The chromosome number in F_2 of O. saliva × O.grandlelumis were 2n= 4x= 48. This showed that the allotriploid of hybrid F1 had been changed into allotetraploid in F2. The chromosome constitution of this allotetraploid remained to be determined. The chromosome behavior was studied dur-ing meiosis from pachytene to telophase Ⅱ. Results showed that the chromosome configuration of F2 be-longed to the type of the nodal section-allosection, and possessed very high rate of anomalous chromosome, the total rate of anomalous chromosome accounting for 87. 13%. The frequency of anoma-lous chromosome were ranked as follows f univalent, chromosome straggling, lagging chromosome,polyvalent, adjoin translocation, unequal division, chromosome bridge, non-disjunction and loosc pair-ing in descent order. The adjoin translocation was the topic in this study. With this translocation, no vital-ity gametes were produced in F2. However, this is a mutua1 translocation, hence that is very useful for breeding.

关 键 词：水稻 栽培稻 大颖野生稻 多倍现象 细胞遗传 

分 类 号：S511.032[农业科学—作物学]