抗白粉病小麦新种质的选育及细胞学鉴定

Breeding of Novel Wheat Germplasm Line SN 996221 with Powdery Mildew Resistance and Its Cytological Identification

利用杂交、回交、自交相结合的方法从小麦烟农15与中间偃麦草(Thinopyrumintermedium(Host)Bark worth andDewey,E1E1E2E2StSt,2 n=6 x=42)杂交后代(BC3F6)中选出抗白粉病种质系SN996221。在对其白粉病抗性等主要农艺性状鉴定的基础上,进行了细胞学分析。结果表明:SN996221高抗小麦白粉病,其抗性可能来源于中间偃麦草;其根尖细胞染色体数目为2 n=42,花粉母细胞减数分裂中期Ⅰ(PMC MⅠ)染色体构型为2 n=21Ⅱ,与普通小麦的杂种F1PMC MⅠ大多数细胞能观察到2个单价体,染色体构型为2 n=1.02Ⅰ+20.49Ⅱ,SN996221可能是一个小麦-中间偃麦草的异代换系。

A novel wheat germplasm with powdery mildew resistance, SN 996221, was produced from the progeny （ BC3F6 ） of Thinopyrum intermedium and wheat variety, YannonglS, by the meaning of hybridization, back-crossing, and self-crossing. On the base of powdery mildew resistant identification, it was characterized by using of morphological and cytological analysis. The results were as follow： SN 996221 was high resistant to powdery mildew, which resistance probably derived from Thinopyrum intermedium. The chromosome number of SN 996221 in root tip cell was 2n =42 and its chromosome configuration at PMC MI was 2n=21Ⅱ. Two univalents can be obseved in most of poll mother cells of hybrids F1 at PMC MI and its chromosome configura-tion was 2n=1.02 I＋20.49Ⅱ, which indicated that SN 996221 was probably a wheat-Thinopyrum intermedium alien substitution line.