Division of Plant Physiology, Indian Agricultural Research Institute, 110 012, New Delhi, India.
Photosynth Res. 1987 Jan;12(3):265-72. doi: 10.1007/BF00055126.
Photosynthetic(14)CO2 assimilation, ribulose 1, 5-bisphosphate carboxylase (RuBPC), phosphoenol pyruvate carboxylase (PEPC) and dry matter (DM) production were examined in wheat under varying levels and forms of nitrogen.(14)CO2 assimilation increased gradually after germination reaching a peak value at anthesis, followed by a sharp decline. A similar pattern was observed for both the carboxylases, RuBPC and PEPC activities. Increase in nitrogen levels, in general, brought about a significant increase over the control (zero-nitrogen) in(14)CO2 assimilation, RuBPC, PEPC activities and DM production. There were no significant differences in RuBPC activity and(14)CO2 assimilation with respect to the forms of nitrogen. Significantly higher PEPC activity and DM was observed in plants supplied with nitrate-nitrogen (NO3-N), as compared to those supplied with ammonium-nitrogen (NH4-N). The significance of PEPC activity in C3 photosynthesis is discussed in relation to DM distribution.
在不同氮水平和形式下，对小麦的光合（14）CO2 同化、核酮糖 1,5-二磷酸羧化酶（RuBPC）、磷酸烯醇丙酮酸羧化酶（PEPC）和干物质（DM）生产进行了研究。（14）CO2 同化在萌发后逐渐增加，在开花期达到峰值，随后急剧下降。两种羧化酶的活性都表现出类似的模式。氮水平的增加通常会使（14）CO2 同化、RuBPC、PEPC 活性和 DM 生产比对照（零氮）显著增加。氮的形式对 RuBPC 活性和（14）CO2 同化没有显著影响。与供应铵态氮（NH4-N）的植物相比，供应硝态氮（NO3-N）的植物的 PEPC 活性和 DM 明显更高。PEPC 活性在 C3 光合作用中的重要性与 DM 分布有关进行了讨论。
