XVI International Botanical Congess

The Acanthaceae Barleria lupulina, introduced to Venezuela from Africa is distributed in Zulia and Bolivar States, and was used in this study to determine its response to water limited conditions, since this information is lacking in the literature. The plants were irrigated every 2(RI), 5(RII) and 15 days (RIII). The relative water content, and leaf water potentials were measured. Leaf area decreased 71% and 96%, and leaf biomass 39% and 85% in RII and RIII, with decreasing water potentials. Inflorescens and seeds were greatest in RII. The less frequent watering regime affected assimilate distribution because R/S, LAR, LWR and SLW decreased 20%, 88%, 88% and 73%. From preliminary work, it appears that Barleria lupulina does not have osmotic adjustment.