普通小麦体细胞无性系R_2代变异发生特点  

Characterization of Occurrence of R2 Somaclonal Variation in Common Wheat

作　　者：梁竹青[1] 高明尉[1] 成雄鹰[1] 刘国振[1] 

机构地区：[1]浙江农业大学,浙江杭州310029

出　　处：《作物学报》1995年第1期49-56,共8页Acta Agronomica Sinica

摘　　要：小麦R_2代体细胞无性系变异存在4种发生方式,即全株性稳定变异,全株性分离变异,穗系嵌合稳定变异,穗系嵌合分离变异。其中稳定变异相当普遍、约占总变异的1/3。发生阶段较早的全株性变异多于发生较迟的穗系嵌合变异。不同的变异性状有不同的发生方式。株型、穗型、芒型和叶色变异多为分离变异,熟期为稳定变异,株高、腊质等兼有稳定及分离变异,其中某些性状是显性突变的结果。多数分离性状的分离均属简单分离,且很少见到基因突变的嵌合现象。R_2代的平均单株变异率要比理化诱变的相应突变频率高出一个数量级。Four kinds of occurrence patterns of somaclonal variation of several major traits were found in the R2 generation of common wheat, i.e. R2 family non-segregation or stable variation. R2 family segregating variation, R2 line chimeric stable variation and R2 line chimeric segregating variation. Among these the stable variations occurred more commonly in the R2 population, and amounting to one third of the total variation in this study. Frequency of R2 family variation, which probably had occurred from the single original cell of the callus at an early stage, was higher than that of R2 line chimeric variation, which might have occurred during the process of plantlet regeneration. Different traits had their own distinctive patterns of variation occurrence: plant type, spike type and leaf colour were subject to segregating variation: maturity was liable to stable variation, and plant stature and waxiness had both the pattern of stable variation and that of segregating variation. Part of the variations have proved to be resulted from gene(s) mutation in the dominant direction. Most of the segregating variations displayed simple segregation ratios. Chimerism in R2 segregating lines was rarely seen. The frequency of R2 variant individuals was estimated to be at least 10 times as much as that in the M2 population from radiation and chemical mutation.

关 键 词：小麦 体细胞无性系 全株变异 穗系嵌合变异 

分 类 号：S512.103.5[农业科学—作物学]