(Sengar and Pandey, 1996; Haider et al., 2006; Akinci et al.,
2010). Azmat et al. (2009b) reported that Phaseolus mungo
and L. culinaris plants undertake adaptative mechanisms
aimed to protect photosynthesis against the damaging effects
of lead; foliar morphological modifications were induced by
exposure to 1.2 mM Pb, which resulted in an increased number
of trichomes and stomata, thus allowing these species to maintain
photosystem II efficiency and reduce water evaporation
from the leaves during stress.