摘要
较为系统地研究了两个超高产杂交稻‘两优培九’、‘华安 3号’和多年来大面积推广的常规杂交稻‘汕优6 3’不同生育期的光合色素含量、净光合速率和水分利用效率。结果表明 ,在苗期 ,3个杂交稻的单位叶面积的叶绿素 (Chl)含量差别不大 ,类胡萝卜素 (Car)的含量以‘汕优 6 3’为最高。然而 ,随着发育阶段的推进 ,到分蘖期 ,尤其是抽穗期剑叶的单位叶面积Chl和Car含量 ,两个超高产杂交稻高于‘汕优 6 3’。从苗期到抽穗期 ,超高产杂交稻‘两优培九’和‘华安 3号’的净光合速率 (Pn)都比‘汕优 6 3’高 ,而在苗期的午间强光条件下和分蘖期的早晨以及抽穗期的早晚相对弱光条件下其Pn的差别尤为显著。在苗期 ,‘汕优 6 3’的水分利用效率 (WUE)略高于‘两优培九’和‘华安 3号’ ;到分蘖期和抽穗期 ,在上午 10时之前和下午 14时以后的时间段 ,则是两个超高产杂交稻明显高于‘汕优 6 3’。这些结果说明 ,超高产杂交稻‘两优培九’和‘华安 3号’不仅有较高的Pn和较强的抗光抑制能力 ,而且还能充分利用早晨和傍晚较弱的光强进行光合作用 ,这些是它们之所以高产的重要生理基础。此外 ,超高产杂交稻在生长发育的中后期 (分蘖期和抽穗期 )具有较高的WUE ,有利于节约农业用水。
In the 1970s', by exploiting the poorly understood phenomenon called heterosis (first generation of hybrid plants is typically more vigorous and productive than either parent) in rice, China had improved the yield of rice in F_1 hybrid 20%-30% more than either parent and has since then played the leading role in hybrid rice research and production. In order to further improve rice yield to feed the increasing population, China had carried out the 'super high-yield rice project' since 1996. Tremendous progress was made during the 'ninth five-year plan' and several new varieties of the rice hybrids with 'super-high' yield released. Liang youpeijiu (Pei-ai64S × 9311) and Hua-an3 (X07S × Zihui100) were two of such varieties, both with a yield of more than 10 500 kg·hm -2, compared with the traditional rice hybrid Shanyou63 (Zhenshan97A × Minghui63) with a yield of about 7 500-8 250 kg·hm -2. The two super high-yield rice hybrids had a 20%-30% higher yield. The photosynthetic characters, pigments content, net photosynthesis rate and water use efficiency of the different developmental stages of Liangyoupeijiu and Hua-an3, and the traditional hybrid rice Shanyou63 were studied. The results showed that at the seedling stage, no significant difference in the content of chlorophyll per leaf area was observed among the three rice hybrids, while the carotenoid content of Shanyou63 was the highest. The chlorophyll content and carotenoid of the two super high-yield rice hybrids were higher than that of Shanyou63 at the tillering stage, especially in the flag leaves of the heading stage. The net photosynthesis rate (Pn) of the two super high-yield rice hybrids were higher than that of Shanyou63 from seedling stage to heading stage, especially under the midday strong sunlight of the seedling stage and under the twilight of tillering and heading stages. The water use efficiency of the Shanyou63 was slightly higher than that of the super high-yield rice hybrids at seedling stage, but was lower at tillering and heading stages. The physiological basis of their higher yield in the super high-yield rice hybrids could be attributed to the fact that they had a higher net photosynthesis rate, higher resistance to photoinhibition, and also used the dim sunlight effectively, as seen in our results. The higher water use efficiency of the super high-yield rice hybrids at tillering and heading stages indicates economical use of water.
出处
《植物生态学报》
CAS
CSCD
北大核心
2002年第6期647-651,共5页
Chinese Journal of Plant Ecology
基金
由国家重点基础研究发展规划项目 (G19980 10 10 0 )
光合作用基础研究开放实验室创新资金资助
关键词
超高产杂交稻
生育期
光合色素含量
净光合速率
水分利用效率
Super high-yield hybrid rice, Photosynthetic pigments, Net photosynthesis rate, Water use efficiency
