杂交粳稻“榆杂29”苗期生理优势研究

Exploration on the Physiologic Preponderance of the Japonica Type Hynbrid Rice Variety Yuza29 in Seedling StageZhao Changling1Ye shanghong1Zhang Shuhua2Shi Chan

“榆杂２９”在苗期具下列生理优势：（１）播种萌发后胚乳中（α＋β）淀粉酶活性最高，胚芽、胚根生长最迅速，形态建成最快．（２）硝酸还原酶活性较高，耐肥性好．（３）游离氨基酸和酰胺含量最低，蛋白质合成最快．（４）还原糖含量较高，碳代谢旺盛．（５）根中（琥珀酸）脱氢酶活性较高，根系活力高；（６）过氧化氢酶活性居中等水平，意味着：①光呼吸较低，光合产物损耗较少，利于干物质积累，且ＣＯ２补偿点低，利于加强光合作用；②消除Ｈ２Ｏ２毒性的能力较强，利于光合作用进行．（７）抗逆性最强．①自由水含量最低，束缚水含量最高，“束缚水／自由水”最大；②离体叶片在空气中的失水速率最小，保水力最强；③阴雨后游离脯氨酸含量较高．

Yuza29 displays the next physiologic preponderance in seedling stage.1After sprouting,the activity of (+)amylase in endosperm is the highest.The supreme growth speed of the plumule and radicle suggests the morphogenesis be the quickest.2The comparatively high activity of the nirtate rductase suggests the ability of fertilizer-resisting be comparatively powerful.3The lowest content of the free amino acids and amide suggests the protein-synthesizing be the rapidest.4The fairly high content of the reduction saccharide suggests the carbohydrate metabolism be fairly vigorous.5The quite high activity of the(succinic acid)dehydrogenase in the root suggests the vitality of the root be quite high.6The moderate activity of the catalase suggests:(1)The relatively low photorespiration and the relatively little wastage of the photosynthesis product benefit the accumulation of the dry substance;The relatively low CO2 compensation point also benefits the intension of the photosynthesis;(2)The relatively strong abi