Efectos fisiológicos del estrés hídrico sobre varias especies vegetales. II. Naranja y plátano

The effects produced by water stress and three relative humidity (R.H) levels (3q-53%, 5461% & 62-82%) were measured on photosynthesis, stomatal conductance and transpiration rate. Stomatal opening and density were measured in stressed and non stressed plants of plantain (Dominico-Harton) and orange (variety Valencia). Photosynthetic rate of plantain was reduced significantly under water stress, but reduction of stomatal conductance and transpiration rate were not significantly. Gas exchange rate showed great responses to changes in R.H levels. Stomatal density were higher on the lower surface of plantain leaves. Stomatal opening was reduced significantly in both upper and lower surfaces under water stress conditions. Photosynthetic rate in orange plants was reduced significantly under water stress; this reduction was not significantly in both stomatal conductance and transpiration rate. Gas exchange rate is highly reduced under high R.H. Stomatal opening was strongly affected in plants under water stress condition.