【摘要】 1995—1998年对277份西藏半野生小麦的研究表明:西藏半野生小麦形态类型多样、断穗特征稳定,是六倍体小麦中独特的小穗下节位断裂的裸粒型断穗小麦。在性状聚类中,它与栽培小麦各居一群,泾渭分明,明显特点是断穗性强、成熟早、穗密度偏稀,植株较高,千粒重偏低。通过等电聚焦同功酶分析显示,14个生化位点中有10个位点存在遗传多样性;在 RFLP 分子标记中,第3、4、5、6、7同源群表现多态性,但只有在第5、6、7同源群染色体长臂或短臂上与栽培品种存在不同,因而断穗基因可能存在于5S、5L、6L 或7S 染色体之一上。西藏半野生小麦中有4.5%的材料具有中抗和高抗白粉病能力;蛋白质、赖氨酸含量均超过对照2～5个百分点。建议在不同海拔的加查县和察隅县建立西藏半野生小麦的原位保存点。更多还原

【Abstract】 During 1995—1998,a research programme on comparison between Tibetan semi-wild wheat and cultivated wheat were conducted.277 accessions of semi-wild wheat seeds and 74 accessions of cultivated wheat seeds were used for this experiment.The re- sults showed that Tibetan semi-wild wheat is the special bare-grained and spike-fracture hexaploid wheat with great diversity in morphological characters and stable spike-fracture characters.Cluster analysis showed that Tibetan semi-wild wheat was entirely different from cultivated wheat.The significance of Tibetan semi-wild wheat includes high spike fracture rate,early maturity,low spike density,high plant height and low grain weight. Isozyme analysis by isoelectriphic focusing showed that 10 loci of the 14 bio-chemical loci was found to be of genetic diversity.In the RFLP molecule mark,the No.3,No.4,No. 5,No.6 and No.7 homologous groups showed polymorphism.However,only the No.5, No.6 and No.7 chromosome long arm or short arm were different with that of the cultivat- ed wheat.Therefore,the spike fracture genes might exist in 5S,5L,6L or 7S.4.5% of the semi-wild Tibet wheat has medium or high resistance to powdery mildew.The con- tents of protein and lysine were 2%～5% higher than those of the control.It is suggested that the ideal location for in-situ conservation of semi-wild Tibetan wheat are Gyaca Coun- ty and Zayu County in Tibet.更多还原