中国水稻科学

中国水稻科学

• 研究报告 •    下一篇

杂交水稻根系生理优势及其与地上部性状的关联研究

陆定志   

  • 收稿日期:1900-01-01 修回日期:1900-01-01 出版日期:1987-05-28 发布日期:1987-05-28

Relationship Between Physiological Heterosis of Root and Shoot System of Hybrid Rice Shan-You 6

Lu Dingzhi   

  • Received:1900-01-01 Revised:1900-01-01 Online:1987-05-28 Published:1987-05-28

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被引次数

122

摘要： 连晚杂交水稻汕优6号根系的生长、氮吸收、氨基酸合成能力以及根系活力均超过其亲本三系和常规品种。干种子中α-淀粉酶的存在是杂种幼苗根系生长优势的重要生理基础。营养吸收优势表现在单株氮吸收速率上,并与地上部干物质生产有紧密的联系。从杂交水稻伤流液中分离出31种游离氨基酸,而氨基酸种类和浓度则受地上部营养的制约。生育中、后期缺氮和通气不良会导致根系活力降低;适施氮肥和改善通气条件可有效地提高根系活力,并防止早衰。此外,对杂种优势的早期诊断指标和产量预测指标进行了讨论。

关键词: 杂交水稻, 根系生理优势, 根系活力, 叶老化, 游离氨基酸

Abstract: Hybrid rice Shan-You 6 when grown as second crop followed the first rice crop showed superiority over its parental three lines and the conventional rice cultivars in root growth rate,nitrogen uptake and capacity to synthesize amino acids and root activity. Growth vigor of root system occurred at seed germination.α-amylase in the endosperm of the dry seed is the important physiological basis of high diastase activity at early germination,resulting in seedling growth vigor. The hybrid displayed its nitrogen uptake vigor in term of nitrogen uptake rate per plant.Nutrient uptake and dry matter production are closely related. The 31 kinds of free amino acids were separated from the bleeding sap of the hybrid rice,but the kinds and concentration of free amino acids were restricted by nutrition condition of shoot system. The root activity during the mid and late growth stages would be depressed due to nitrogen deficiency and poor aeration.Adequate nitrogen supply and improved aeration by irrigation management were effective to keep the root activity from antimely decline,thus protecting the leaves from pre-mature senescence.Moreover,the early diagnostic indices of heterosis and the indices in forecasting the rice yield are discussed.