Growth and gas exchange response to water shortage of a maize crop on different soil types

The effect of water shortage on growth and gas
exchange of maize grown on sandy soil (SS) and clay soil
was studied. The lower soil water content in the SS during
vegetative growth stages did not affect plant height, aboveground
biomass, and leaf area index (LAI). LAI reduction
was observed on the SS during the reproductive stage due
to early leaf senescence. Canopy and leaf gas exchanges,
measured by eddy correlation technique and by a portable
photosynthetic system, respectively, were affected by
water stress and a greater reduction in net photosynthetic
rate (AN) and stomatal conductance (gs) was observed on
SS. Chlorophyll and carotenoids content was not affected
by water shortage in either condition. Results support two
main conclusions: (1) leaf photosynthetic capacity was
unaffected by water stress, and (2) maize effectively
endured water shortage during the vegetative growth stage.