Tolerance to low leaf water potential in soybean genotypes

Photosynthetic activity of water stressed plants could be used to assess drought tolerance in soybean (Glycine max L. Merr.). Changes in Photosystem II (PS II) activity during stress integrates the direct effect on PS II activity, analyzed by chlorophyll fluorescence, and responses to decreased CO2 fixation activity due to stomatal closure and photoprotective energy dissipation within the photochemical apparatus. This study analyzed genotypic variation for drought tolerance at low leaf water potentials.