氮水平对水稻光合特性的影响

Effect of Nitrogen Levels on Photosynthetic Characteristics of Rice

用缺氮(ON)、低氮(LN)、中氮(MN)、高氮(HN)、超高氮(SN)盆栽土培的杂交水稻汕优64和金南风为材料,测定植株和叶片的生长状况、叶片总N含量、光合速率、光呼吸速率、气孔导度和叶肉导度的变化.结果表明:供试两品种随着施N量的增加,植株的分蘖数增多,株高增加,气孔密度减少,叶片总N含量、叶绿素含量、光呼吸速率、叶肉导度等均增加.供试两品种的净光合速率变化存在差异,金南风叶片的净光合速率是随着施N量的增加而增加,但汕优 64在HN和SN的条件下净光合速率反而下降,说明在HN和SN的水平上光合碳代谢的途径发生了变化,即光氧化环增加的幅度大于光合还原环.

Pot culture of lack nitrogen(ON, control),low nitrogen(LN),medium nitrogen (MN), high nitrogen(HN) and super high nitrogen(SN) was conducted and the growth of plants and leaves, total N content of leaves, chlorophyll content, photosynthetic rate,photorespiratory rate, stomatal and mesophyll conductance in hybrid rice Shanyou 64 and Kinmaze were investigated. The results showed the tiller numer and height of plants,total N content of leaves, chlorophyll content, photoresiratory rate, mesophyll conductance raised as increasing nitrogen levels, but stomatal density decreased. Hybrid rice Shanyou 64 and Kinmaze had difference in net photosynthetic rate. Net photosynthetic rate of Kinmaze raised as increasing nitrogen levels, but that of Shanyou 64 decreased under HN and SN. The result showed the pathway of photosynthetic carbon metabolism had been changed under HN and SN. The increase of photosynthetic oxidative cycle was more than that of photosynthetic reduced cycle.