摘要
利用砂培试验研究了不同氮素形态对向日葵生长和光合功能的影响.结果表明:NO3- - N NN 处理的株高、叶面积、干物质重显著高于NH4 + - N AA 处理,施用NO3- - N的植株有较高的净光合速率 Pn 和较低的气孔导度 Cs 、细胞间隙CO2 浓度 Ci .不同处理之间Fv/ Fm没有显著差异,NN处理的植株PS 线性电子传递量子效率ΦPS 、光化学荧光猝灭系数q P和表观光合电子传递效率ETR都显著高于AA处理的植株;而非光化学荧光猝灭系数q N则明显低于AA处理的植株.碳同化受到抑制是NH4 + - N条件下净光合速率下降的重要原因.
The effects of different nitrogen forms on the growth and photosynthesis of sunflower (Helianthus annuus L.) were hydroponically studied. The results showed that plant height,leaf area and dry matter of sunflower with the fertilization of nitrate nitrogen were significantly higher than those with the dertilization of ammonium nitrogen and the plants fertilization with nitrate nitrogen presented a higher net photosynthetic rate,a lower stomatal conductancwe (Cs) and a lower concentration of carbon dioxide in intercellular space (Ci).The fertilizations of different nitrogen forms did not significantly differed in Fv/Fm but the plants fertilized with nitrate nitrogen presented a significantly higher quantum yield of ΦPSⅡ linear electron transport (ΦPSⅡ),a significantly higher photochemical quenching (qp) and a significantly higher qpparent electron transport rate (ETR) but a lower non-photochemical fluorescence quenching (qp) than the plants fertilized with ammonium nitrogen.Inhibited carbon assimilation was the important reason for lowered net photosynthetic rate.
出处
《西北植物学报》
CAS
CSCD
北大核心
2005年第6期1191-1194,共4页
Acta Botanica Boreali-Occidentalia Sinica
基金
国家自然科学基金项目 40 0 0 10 10 资助
