论文部分内容阅读
以扬麦16为材料,在小麦幼苗返青期至颖果成熟期内进行干旱处理,研究小麦颖果组织在干旱胁迫下细胞学结构的变化特征。结果表明:(1)在颖果发育过程中,干旱胁迫能促进前期颖果生长,但抑制后期颖果生长。(2)干旱胁迫在颖果发育早期促进果皮组织发育,而在后期阻碍果皮细胞的程序性死亡,降低果皮中淀粉体的降解速率。(3)干旱胁迫下颖果胚乳组织在早期发育较快,但在后期胚乳细胞的进一步生长受到抑制,胚乳淀粉体的积累减少。(4)干旱胁迫下小麦颖果在发育早期胚组织分化早、发育快,但随着干旱的持续,胚体积的进一步扩张受阻,营养物质积累下降。综合而言,干旱胁迫通过改变颖果各组织结构发育影响颖果生长发育,总体表现为在发育前期促进颖果生长,此后随着干旱的持续,阻碍颖果的进一步发育和成熟。
Yangmai 16 was used as a material to conduct drought treatment during the ripening period of wheat seedling until the ripening stage of caryopsis to study the changes of cytological structure of wheat caryopsis tissue under drought stress. The results showed that: (1) During the development of caryopsis, drought stress could promote the growth of caryopsis, but inhibit the growth of caryopsis. (2) Drought stress promoted the development of pericarp tissue in the early stage of caryopsis development, but blocked the apoptosis of pericarp cells in the late stage and decreased the degradation rate of amylopectin in the pericarp. (3) Caryoplasm endosperm developed rapidly in early stage under drought stress, but the further growth of endosperm cells was inhibited in late stage, and the accumulation of amyloplast in endosperm decreased. (4) The differentiation of wheat caryopsis in early stage of development under drought stress was rapid and early development, but with the prolongation of drought, further expansion of embryo volume was blocked and the accumulation of nutrients decreased. Taken together, drought stress affects the growth and development of caryopsis by changing the structural development of caryopsis. The overall performance is to promote the growth of caryopsis at the early stage of development. Afterwards, the drought continues to hinder the further development and maturation of caryopsis.