【摘要】 以太湖流域粳稻的1440个品种为材料,将三叶期幼苗置于照光低CO₂空气的密闭系统内或照光的高O₂空气的密闭系统内生长,由生长反应检出高净光合的品种。还研究了光合色素在670nm的峰值与净光合强度的关系。明确了这三种技术都可用以检出高净光合的材料。由于高O₂有两种作用—O₂抑光合与O₂促光呼吸,因此它对高净光合特性的筛选比低CO₂筛选更为严格,即在低CO₂筛选下入选的材料,可用高O₂筛选检出净光合速率更高的材料。 研究结果还明确了在太湖流域粳稻中,中熟类型净光合速率高的材料比晚熟类型多,文内对这种特性的形成做了讨论。从筛选出的100个高光合速率的品种,推荐出既具有高净光合速率,同时又具有其它极优的农艺性状的28个品种,为高光效育种的种质资源。更多还原

【Abstract】 Experiments were conducted to search for rice cultivars with high photosynthetic rates by means of growing seedlings in an illuminated hermetic chamber flushed with low CO2 air or high O2 air. Absorbance of photosynthetic pigments at 670 nm was also used as a parameter for screening photosynthetic efficiency. All the three techniques were proved useful, among which high O2 air screening was more effective because it increased direct O2 inhibition of photosynthesis and enhanced photorespiration, thus making only the cultivars with highest photosynthetic rates survived.Out of 1440 cultivars screened 100 cultivars with high photosynthetic rates were sorted out. Most of them were medium maturing varieties. Taking other desirable agronomic traits into account, 28 cultivars were recommended as source material for breeding high yielding varieties with high photosynthetic rates.更多还原