Elymus sibiricus, E. nutans 和 E. burchan-buddae 的形态学鉴定及其染色体组亲缘关系的研究

为了进一步研究Elymus sibiricus L.、E．nutans Griseb．和E．burchan-buddae(Neuski)Tzelev[＝Roegneria nutans(Keng)Keng]的外部形态差异及其系统学关系，本文对这三种植物的6个穗部形态性状进行了观测和比较，并对这三个Elymus种进行了种间杂交及杂种F1的减数分裂染色体配对行为的分析研究。结果表明：这三个Elymus种的穗长及颖长等性状均变异很大，而内稃的长、宽则变异不大并具有明显的种间差异。E. nutans×E．barchan-buddae及E.nutans×E．sibiricus的杂种F1均完全不育，减数分裂不规则。E．nutans×E．burchan-buddae杂种F1的减数分裂构型为：7.70I+13.40Ⅱ+0.06Ⅲ+O.08 Ⅳ，而E．sibiricus×E．nutans杂种F1的构型为11.98 Ⅰ+9.61Ⅱ+O.64Ⅲ+0.39Ⅳ+0.01V。由本实验的形态学和细胞学的研究结果得出以下结论：1．利用内稃形态性状结合穗部其它性状的差异能对这三个物种进行较准确的鉴定；2．E．nutans与E.burchan-buddae的亲缘关系较近，而E．nutans与E．sibiricus的亲缘关系则较远；3. E，burchan-buddae×E．nutans的杂种Fl中存在着染色体配对控制因子。

MORPHOLOGICAL IDENTIFICATION OF ELYMUSSIBIRICUS,E.NUTANS,AND E.BURCHAN-BUDDAE,AND THEIR GENOMIC RELATIONSHIPS

In order to investigate morphological variations of Elymus sibiricus L. , E. nut ans Griseb. , and E. burchan-buddae (Nevski) Tzvelev [=Roegneria nutans (Keng) Keng], and to explore their systematic relationships, six morphological characters were measu red and compared between the Elymus species. Interspecific hybridizations between E. nut ans and E. sibiricus, and E. burchan-buddae were carried out with the aid of embryo resctre. Chromosome pairing behaviour was also analysed at metaphase- I of meiosis in pollen mo th-er cells of F, hybrids. Morphologic characters, such as length of spikes and length of glumes varied considerably between different individuals of each species, whereas length and width of paleas were quite stable and different between species. The interspecific hybrids were completely sterile and their meioses were irregular. Meiotic configuration of E. nutansXE. l,ur-chan-buddae was 7. 70 I 13. 40 I 0. 06 I 0. 08 W , whereas that of E. sibiricusX E. nutans was 11. 98 I 9. 61 I 0. 64 I 0. 39 W 0. 01 V . It is concluded from the morphological and cytological study that (1) it is possible to identify the three Elymus spe;cie;3 using the palea character, in addition to other traditionally applied characters; (2) Elymus nutans and E. burchan-buddae have a comparatively high genomic relationship, while E.. nutans and E. sibiricus have a relatively low genomic affinity to one another; and (3) a ce rtain chromosome pairing regulator was presented in the hybrid between E. burchan-buddai; and E. nutans.