小冰麦异附加系的体细胞无性系建立及其变异的研究

从7种小冰麦异附加系的幼叶和成熟胚诱导出愈伤组织,建立了体细胞无性系,获得大量试管苗,并移栽成活。实验设计了适于小冰麦异附加系组织培养的 WG 培养基。愈伤组织诱导采用二次诱导方法。第一诱导培养基为 WG_2附加4mg/1 2,4-D、1mg/1 NAA。第二诱导培养基为 WG_2附加2m//1 2,4-D、0.5mg/1 NAA,和0.25mg/1KT。分化培养基为 WG_3附加0.5mg/1 KT、1mg/1 NAA 和100mg/1 Ad。再生植株的染色体检查表明,异附加系无性系的染色体数变异明显。保持2n=44的再生植株只有34.4%,而且变异植株中回复到2n=42的植株较多。再生植株中约有1/2发生了形态变异。在变异植株的花粉母细胞中观察到染色体的交换、易位等结构变化。特别在愈伤组织细胞中观察到多条染色体融合成多着丝点染色体和体细胞的染色体交叉,说明无性系中发生了染色体的交换和易位。

STUDY ON-THE ESTABLISHMENT AND VARIATION OF SOMACLONES FROM WHEAT.WHEATGRASS ALIEN ADDITIONAL LINES

Calli were induced from the young leaves and mature embryos of seven wheat-wheatgrass alien additional lines,and somaclones were established from the calli.A large number of plantlets were obtained and survived after transplantation. The medium WG used for tissue culture of wheat-wheatgrass alien addition lines was set up in the experiment.The methods induced callus with two kinds of media were used.The first medium WG_2 supplemented with 4mg/l 2,4-D and ling/l NAA was used for callus for- mation.The second medium was WG_2 with 2mg/l 2,4-D,0.5mg/l NAA and 0.25mg/l KT. Differentiation medium used was WG_3 with 0.5mg/l KT,ling/l NAA and 100mg/l adenylic acid. The examination of the chromosomes in regenerated plants indicated that the chromoso- mal number variation was remarkable.The plants maintaining 2n=44 were only 34.4% of the total regenerated plants,and the plants with the chromosomal number returned to 2n=42 ma- de a relatively greater part of the variational plants regenerated.About half of the regenera- ted plants showed morphological variations.The crossover,translocation and other chromo- somal structural changes were found in PMCs of the variational plants regenerated.Mean- while,the polycentric chromosome derived from the fusion of several chromosomes and chias- mata of somatic chromosomes were clearly observed in callus cells,indicating that crossover and translocation occured in somaclones.