为了研究气孔的动力学,蒸腾作用,以及叶片发育过程中不同光照强度和CO2条件下的光合作用,气孔导度的光响应和CO2响应(gsw),蒸腾速率(Tr),在出叶后(DAE)的不同天数观察到水稻叶片的净光合速率(Pn)。结果表明:(1)随着光合有效辐射(PAR)的增加,叶gsw,Tr,Pn最初迅速线性增加,然后逐渐上升到最大值,然后稳定或呈现下降趋势。最大gsw,Tr,和Pn较小,并且老叶比幼叶发生得更早。gsw,Tr,随着DAE的增加,Pn均呈线性下降趋势,下降速度随着PAR的降低而减慢;(2)随着CO2浓度(Ca)的增加,Gsw和Tr逐渐下降到稳定的最小值,而Pn线性缓慢增加,直至最大,然后保持稳定或下降。gsw,Tr,和Pn值最初保持较高,然后随着DAE的增加而降低。这些结果有助于理解gsw中的动力学,Tr,水稻叶片生长过程中的Pn及其对不同光照和CO2浓度条件的响应,并通过提高叶片水平的气孔导度,为在田间和更大范围内估算稻田生态系统的动态蒸散量和净生态系统生产力提供了机械支持,蒸腾作用,和光合作用。
To investigate the dynamics of stomata, transpiration, and photosynthesis under varying light intensities and CO2 conditions during leaf development, the light response and CO2 response of stomatal conductance (g sw), transpiration rate (T r), and net photosynthetic rate (P n) were observed for rice leaves at different days after leaf emergence (DAE). The results showed that (1) as photosynthetically active radiation (PAR) increased, leaf g sw, T r, and P n initially increased rapidly and linearly, followed by a more gradual rise to maximum values, and then either stabilized or showed a declining trend. The maximum g sw, T r, and P n were smaller and occurred earlier for old leaves than for young leaves. The g sw, T r, and P n all exhibited a linear decreasing trend with increasing DAE, and the rate of decrease slowed down with the reduction in PAR; (2) as the CO2 concentration (C a) increased, g sw and T r decreased gradually to a stable minimum value, while P n increased linearly and slowly up to the maximum and then kept stable or decreased. The g sw, T r, and P n values initially kept high and then decreased with the increase of DAE. These results contribute to understanding the dynamics in g sw, T r, and P n during rice leaf growth and their response to varied light and CO2 concentration conditions and provide mechanistic support to estimate dynamic evapotranspiration and net ecosystem productivity at field-scale and a larger scale in paddy field ecosystems through the upscaling of leaf-level stomatal conductance, transpiration, and photosynthesis.