我国三个野生稻种粗线期核型的研究

Studies on Pachtyene Karyotype of Three Wild Oryza Species in China

为了探求栽培稻同野生稻种的亲缘关系,采用去壁、低渗和Giemsa染色制片法,比较分析了我国的普通野稻(Oryza rufipogon Gri ff.=O. Perennis Moench)、药用野稻(O.officinalis Wall.)、疣粒野稻(O.meyeriana Baill)和栽培稻(O.sativa L_)的粗线期核型。试验结果表明,最长染色体长度与最短染色体长度的比值,以普通野稻同栽培稻最为接近。根据Levan等的臂比率标准,普通野稻的核型为7M+5SM;药用野稻为6M+5SM+1ST;疣粒野稻为7M+5SM;栽培稻为6M+6SM。普通野稻同栽培稻具有相同类型和编号的染色体数目最多,核型最相似,表明二者的亲缘关系最为密切。本文还就种内核型变异的主要表现及引起变异的可能原因进行了讨论。

In order to elucidate the consanguineous relationship between cultivated rice and wild rice species, by means of wall degradation, hypotonic treatment,flame- drying and stained with Giemsa method, karyotypes of three wild Oryza species (O. rufipogon Grill=O. perennis Moench, O. afficinalis Wall and O. meyeriana Baill) and one cultivated rice species (O. saliva L.), all indigenous to China, were analyzed. Karyotype analysis showed that the ratio of the longest chromosome length/the shortest chromosome length between O. sativa and O. rufipogon was most similar. Based on Levan's arm ratio criterion, karyotypes of O. rufipogon, O. officinalis, O. meyeriana and O. saliva were 7M+5SM, 6M+5 SM+1 ST, 7M-5 5 SM and 6M+6SM respectively. O. rufipogon and O. sativa had the most number of chromosome with the same chromosome type and chromosome number. The results of pachytene karyotypic analysis indicated that O. rufipogon and O. saliva resembled each other in karyotype. It might be inferred that O, sativa is related to O. rufipogon most closely. In addition, main manifestations of intraspecific karyotypic variation and accounts for the variation have also been discussed.