水稻光合作用对加富CO_2的响应

Response of Rice Photosynthesis to CO_2 Enrichment

整个生育期经高Co（600μl／L）处理的5种水稻的PSⅡ原初光化学效率（Fv／Fm）与空气CO2（350μl／L）中生长的对照无明显的差异。高CO2下绿黄占3号，特三矮2号和普通野生稻叶片的平均光合放氧速率分别比各自的对照有所提高，而Ⅱ优4480和药用野生稻的光合速率低于对照。高CO2下生长的水稻叶片叶绿素含量和类胡萝卜素含量降低，生长后期的降解加快，并抑制了水稻的暗呼吸。绿黄占3号、特三矮2号和普遍野生稻的干物重在高CO2下较对照均有所增加，而Ⅱ优4480和药用野生稻的则下降。表明水稻不同种之间和种内的光合作用和生物量对高CO2的响应有一定的差异。

For understanding the photosynthetic response of crop Plans to CO2 enrichment, three rice varieties and two wide rice peies were grown in two chambers located outdoors and exposed to naod sunlight during their livesThe CO2 concentaions in the chambers were kept at 350 μl/L (ambient) or 600μl/ L(elevaed) monitortng by an infrared CO2 analyzer with computer Fv/Fm in leaves of rice species and varieties including Oryza satha Luhuangzhan 3,O. sativa Tesanai 2, 0. sativa Ⅱ You 4480, O. officinalis (wild rice species) and O spontanea (wide rice speies ) showed no significan diference between Plants growing under elevated and ambient CO2 As compared with the control at ambient CO2, the average photosynthetic oxygen evolution rates of Luhuangzhan 3, Tesanai 2 and O . spontanea undr elevated CO2 were 9% ～20% higher, while those of cv. Ⅱ You 4480 and O. officinalis were 7% - 12% lower The photosynthetic pigment content and ed respiratary rate of rice leaves decreased under elevated CO2Increases in for weigh by elevated CO2 were observed in Luhanfor 3, Tesanai 2 and O.spontanea, but a decrease was foun in Ⅱ You 4480 and O.officinalis Photosynthetic acclimation was not observed in cv Luhuangzhan 3,Tesanai 2 and O. spontanea in a longterm experent with elevated CO2. There are both intraspecific and specific differnces in the repesponses of photosynthesis and yield to elevated CO2