一个小麦-中间偃麦草异代换系的形态学和细胞学鉴定

Morphological and Cytological Identification of Wheat- Elytrigia intermedium Alien Substitution Line Shannong 0095

中间偃麦草含有丰富的优良基因 ,在小麦的遗传改良中具有重要利用价值 .对从中间偃麦草与小麦品种烟农 15杂种后代 BC2 F4 中选育的小麦种质系山农 0 0 95进行形态学和细胞学鉴定 ,结果表明 :山农 0 0 95株高 78cm,穗长 17.3cm,旗叶长 36 .3cm,旗叶宽 3.0 3cm,茎杆粗壮 ,繁茂性好 ,既长又宽的旗叶、长圆锥型穗是其显著的形态学特征 ;其根尖细胞染色体数目为 2 n=4 2 ,花粉母细胞减数分裂中期 PMC M 染色体构型为 2 n=2 1 ;它与普通小麦的杂种 F1 PMC M 绝大多数细胞出现 2个单价体 ,没有观察到多价体 ,平均染色体构型为 2 n=2 0 .0 8 +1.84 .以上结果表明 ,山农 0 0 95是一个小麦 -中间偃麦草的双体异代换系 .

Elytrigia intermedium carries fruitfully valuable genes for wheat genetic improvement.A novel wheat germplasm,Shannong 0095,bred from the progeny (BC_2F_4) of Elytrigia intermedium and wheat cultivar,Yannong 15,was identified by using morphological and cytological analysis.The results were as follow:Shannong 0095 had plant height of 78 cm,spike length of 17.3 cm,mean spike number of 74,flag leaf length of 36.3 cm,flag leaf width of 3.03 cm,and stout haulm,which showed that it was more luxuriant than that of Yannong 15.Long and wide flag leaf and long and conical spike shape were its remarkable morphological marks.The chromosome number of Shannong 0095 in its root tip cell was 2n=42 and its chromosome configuration at PMC MⅠ was 2n=21Ⅱ.Two univalents were always observed in most cells of hybrids F_1 between Shannong 0095 and wheat parent at PMC MⅠ,but no multivalent was found.And the chromosome configuration of hybrids F_1 at PMC MⅠ was 2n=20.08Ⅱ+1.84Ⅰ.These results preliminarily indicated that Shannong 0095 was a wheat-Elytrigia intermedium alien disomic substitution line.