Fig. 3

The relationship between the net CO₂ assimilation rate (A) and each of the chlorophyll fluorescence parameters obtained by rapid light curves for control and drought stressed maize plants. a F, fluorescence yield; b Y(NO), quantum yield of nonregulated energy dissipation; c Fm’, maximum fluorescence yield on light-adapted leaf; d Y(II), effective PSII quantum yield; e qN, coefficient of non-photochemical quenching (lake model); f Y(NPQ), quantum yield of regulated energy dissipation; g NPQ, non-photochemical quenching; h qP, coefficient of photochemical quenching (puddle model); i qL, coefficient of photochemical quenching (lake model); j PS/50, apparent rate of photosynthesis. All chlorophyll fluorescence parameters were obtained from RLC’s in the light step at 280 µmol m⁻² s⁻¹ of actinic lighting. The data used for correlation were obtained from ten measurements over the experimental period