小麦幼胚体细胞无性系的POD活性及组织化学研究  

Histo-chemical and POD activity study on somaclone derived from immature embryos of bread wheat(Triticum aestivum L.)

作　　者：王睿辉[1,2] 王璐[1] 刘桂茹[1] 温树敏[3] 谷俊涛[3] 陈耀锋[2] 

机构地区：[1]河北农业大学农学院,陕西杨凌712100 [2]西北农林科技大学农学院,陕西杨凌712100 [3]河北农业大学生命科学学院,河北保定071001

出　　处：《西北农林科技大学学报（自然科学版）》2013年第5期37-42,共6页Journal of Northwest A&F University(Natural Science Edition)

基　　金：国家自然科学基金项目(30600389);国家转基因生物新品种培育项目(2009ZX08002-012B)

摘　　要：【目的】研究小麦幼胚体细胞无性系在继代过程中发生的组织化学变化以及胚性和非胚性无性系的POD活性和组织化学差异。【方法】以小偃22等12个小麦品种(系)幼胚为试材,诱导愈伤组织,测定其POD活性,并采用番红-固绿染色法观察小麦幼胚胚性无性系在继代过程中的组织学变化及其与非胚性无性系的组织结构差异。【结果】与非胚性无性系相比,小麦胚性无性系的POD活性较高。在组织切片上,胚性无性系(胚性愈伤组织)细胞排列有序,体积小,核大,胞质浓厚;个别细胞出现纤维素化的细胞壁,胚性细胞团与周围细胞呈明显的隔离状态,有体细胞胚和纤维素化的环纹导管出现。非胚性无性系的细胞排列松散,组织性差,细胞质稀薄,核小或无,多为薄壁细胞,其细胞壁多木质化,有木质化的导管出现。在继代过程中,以小偃22为代表的小麦品种,其幼胚胚性无性系有胚性细胞团积聚,在组织表面或内部有胚状体分化,个别组织中甚至有环纹导管出现;而非胚性无性系除具有上述非胚性细胞的特征外,不能或很少出现胚性细胞团和胚状体。【结论】与非胚性无性系相比,胚性无性系具有更好的细胞组织性和较高的POD活性,胚性细胞比例更高。小麦幼胚无性系在继代过程中发生的胚性降低与细胞的组织化程度有关。【Objective】 Embryogenic somaclone induced from immature embryos is of great importance in transgenic and traditional breeding of wheat due to its higher totipotency than that of other explants.However,decrease or loss in embryogeny of somaclone during subculture has prevented the further application of such clones.Therefore,the objective of present study is to explore the reason using POD activity measurement and histochemistry methods.【Method】 Histo-and bio-chemistry methods were employed to invstigate the changes of somaclone during subculture,and to compare the differences among embryogenic-（EC）and nonembryogenic calli（NEC）,induced from twelve wheat cultivars（lines）.【Result】 Compared to non-embryogenic calli（NEC）,embryogenic calli（EC）expressed higher peroxidase activity（POD）than that of NEC.Under microscopy observation,cells of EC with small cellular volume,big nuclei and thick cytoplasm,arranged in order,while cells of NEC arranged loosely with big cellular volume,small or no nuclei and thin cytoplasm.Some cells in EC emerged as thickened cell walls and ingrowed,even aggregate to form embryoid or embryoid-like structures.In NEC,cells showed somewhat vacuolization tendency and parenchyma cells occupied most ratio.Also,lignified trachea appeared in NEC.During subculture,cells of embryogenic calli,derived from and represented by wheat cultivar Xiaoyan 22,aggregate to form embryoid or embryoid-like structures from the external or internal of calli.Also,there appeared ring vessels in embryogenic calli during subculture.For non-embryogenic calli,little or no embryogenic cells aggregation and embryoid can be observed during the course of subculture.【Conclusion】 Compared to NEC,cells in EC organized in better order and has higer POD activity and higher ratio of embryogenic cells.During the course of subculture,the decrease of embryogeny in EC was ascribed to the cell organization.

关 键 词：小麦 胚性无性系 POD活性 组织化学 

分 类 号：S512.135.3[农业科学—作物学]