Response of Bean (Phaseolus vulgaris L.) to Elevated $[\mathbf{CO_{2}}]$ in Yield, Biomass and Chlorophyll Fluorescence

The impact of elevated
$[\text{CO}_{2}](\mathrm{e}[\text{CO}_{2}])$
in on yield, biomass (BM) and chlorophyll fluorescence (ChlF) was analyzed in three genotypes of common beans (Phaseolus vulgaris L.), a key food-security crop. Active- and passive-sensed ChlF traits acquired by the Light-Induced-Fluorescence-Transient (LIFT), Moni-Pulse-Amplitude-Modulation (MoniPAM), and Fluorescence Box
$(\text{FloX})$
instruments were compared. Total biomass increased for all genotypes under
$\mathrm{e}[\text{CO}_{2}]$
, but their biomass partitioning significantly differed. The highest yielding genotype under
$\mathrm{e}[\text{CO}_{2}]$
also showed the highest photosynthetic activity according to different active-sensed ChlF methods. Furthermore,
$\mathrm{e}[\text{CO}_{2}]$
resulted in earlier senescence, which was detected by either satellite- or FloXderived Normalized Difference Vegetation Index (NDVI). Moreover, we observed a significant agreement between MoniPAM- and LIFT-measured ChlF data
$(\mathrm{R}^{2}=0.89, p= 0.02)$
, as well as between SIF and FloX measurements
$(\mathrm{R}^{2}= 0.62,p=0.03)$
.