虉草种子成熟时构件的主要生理生化变化

Studies on the Changes of Physiology and Biochemistry in Structural Components during Phalaris arundinacca L. Seed Development

通过测定不同成熟期各构件可溶性糖(SS)、蔗糖(SU)、淀粉(ST)含量,呼吸作用中间产物丙酮酸(PA)含量及硝酸还原酶活性(NR),研究虉草种子成熟时灌浆物质在源、流、库器官间转移规律,探讨种子千粒重与构件物质含量的相关性。结果表明:(1)生殖枝中SS、ST、SU和PA含量及NR活性在发育期间和构件间均变化显著;(2)构件中SS、SU含量和NR活性随种子发育进程显著先增后降,ST含量显著增加,PA则显著下降;(3)穗轴中糖分含量、PA含量及NR活性数倍于其他构件,是灌浆物质累积、合成、转化及调控中心;(4)蜡熟期ST含量与灌浆期SS含量、乳熟期ST含量显著正相关(P<0.05),与灌浆期和乳熟期NR活性和ST含量均显著正相关(P<0.05);(5)种子饱满度(千粒重)与叶(源)中SS含量,与茎(流)中SU含量,与穗柄(流)中SS、SU和PA含量,与穗轴(流)中SS、SU、PA含量和NR活性,与种子(库)中NR活性、ST含量呈显著正相关。总之,各构件均参与"源-库"的物质运输,穗轴对源库流起调控作用。

In order to research the transfer rule of filli seed development and to explore the relationship between ng material from the source to the library during 1000-seeds weight and material content of cornponents, some index, including soluble sugars （SS）, sucrose （SU）, starch （ST）, respiration intermediate product pyruvate acid （PA） content and nitrate reductase activity （NR） were measured. The results showed that： （1）there was significant difference in SS, ST.SU and PA content and NR activity during the seed development and among structural components （P〈0.05）. （2） With seed developing, SS and SU content and NR activity of structural component significantly first increase and then decrease （P〈0.05）, but ST content significantly rise, PA content significantly decrease （P〈0.05）. （3） SS, PA content and NR activity in the spike-stalk were several times higher than those of other components. Thus spike-stalk was the center for filling material accumulation, synthesis, transformation and control. （4） During dough stage, SS content had a significantly positive correlation with SS content in filling stage, ST in milk stage, and NR activity and ST content in filling and milk stage（P〈0. 05）. （5） Seed plumpness（1000-seed weight） had a significantly positive correlation with SS content in leaf, SU content in stem, SS, SU and PA content and NR activity in spike-stalk, NR activity and ST content in seed （P〈0.05）. In a word, each component participated in material transportation from source to library during seed development and the spike-stalk had a control function on source-library flow.