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Drought tolerance is important for the survival and productivity of plants in environments where drought periods are increasing as a result of climate variability attributable to natural causes and climate change caused by human activities. The objective of this study was to evaluate the dynamics of photosynthesis (A), stomatal conductance (gs) and intrinsic water-use efficiency (WUE=A/gs) as a function of soil moisture content over a period of drought and the post-stress recovery of 14 cowpea genotypes. The studied genotypes tolerated soil moisture tensions close to -2 Mpa with no permanent wilting. Starting at a soil hydric potential of -0.7 MP a, decreases in photosynthesis (A), stomatal conductance (gs) and transpiration (E) were evident, as well as an increase in A/gs, which varied by genotype. Estimating with regression models allowed for the discrimination of the degrees of drought tolerance between the cultivars. At 4 days after resuming hydration, no significant differences were found between the means of A, gs, A/gs and E, suggesting drought tolerance in all genotypes. The genotypes: L-047 and L-034 conserved between 4 and 6 leaves, displaying the highest delayed leaf senescence during drought. Furthermore, they presented the highest biomass at 16 days post-stress recovery

En el Centro de Investigaciones Turipaná de la Corporación Colombiana de Investigaciones (Corpoica) (Cereté, Córdoba, Colombia –8° 31' N y 75° 58' O, a 13 m.s.n.m) se estudiaron las correlaciones, ambientales y genéticas entre seis caracteres de 24 cultivares de berenjena (Solanum melongena). Para el efecto se utilizó un diseño de bloques completamente al azar con tres repeticiones y unidades experimentales de 10 m2. Los resultados mostraron que las correlaciones fueron de mayor o igual magnitud que las fenotípicas, mientras que las ambientales fueron de escaso valor. El número de frutos y el rendimiento estuvieron genéticamente correlacionados (r = 0.56, P < 0.01), la longitud y la resistencia del fruto mostraron correlación genética negativa (r = -0.68, P < 0.01) y entre el rendimiento y peso de fruto la correlación fue muy baja (r = 0.04). El número de frutos y su peso de frutos se correlacionaron de manera negativa (r =-0.63, P < 0.01). El número de frutos por planta puede ser utilizado como criterio de selección para la obtención de cultivares de berenjena de altos rendimientos.