水稻适应广幅光强的光合特性及品种间差异

Identification of Photosynthetic Characteristics Adapted to Wide Range of Light Intensities in Rice Varieties

在自然条件下,水稻总是生活在一个开放变动的环境系统中,而强光和弱光都会使其光合受到抑制。近年来的研究指出,水稻品种间对光强的适应性存在明显差异。有关耐光氧化、耐荫特性及其鉴定技术也有大量报道。另外,还初步研究了水稻品种适应广幅光强的光合特性。在上述基础上,本文比较了籼粳杂交稻和籼型杂交稻的耐光氧化和耐荫特性,探讨了杂种F_1和亲本的关系及适应广幅光强品种的筛选技术和鉴定指标,为杂交稻抗逆稳产育种提供生理依据。

The photosynthetic characteristics of indica-japonica cross combination and indica cross combination were identified under photooxidation and shading Conditions. Results showed that japonica rice 02428 and indica-japonica hybrid rice Yayou2 were with photosynthetic characteristics adapted to wide range of light intensity; indica hybrid rice Shanyou 63 was tolerant to shading and sensitive to photooxidation; indica rice 3037, Minghui 63, Zhenshan 97A were sensitive to photooxidation and shading. The varieties with adaptation to wide rang of light intensity were characterized by less accumulation of toxic superoxide anion radical (O(?)) higher induced activity of superoxide dismutase (SOD), an endogenous O(?) scavenger and relative stability in photosynthetic key enzyme RUBPcase activity. Simultaneously, these varieties also possess relative stability in specific leaf weight and photosynthetic productivity under shading condition (1/5 nature light). At present, it would be necessary to be combined photosynthetic characteristics adapted to wide range of light intensity with improved plant-type for high-yield breeding.