S16 - Session P2 - II - tree architecture and modeling - Photosynthetic response of Plukenetia Volubilis L. to light intensity and soil water availability in young plants

Authors: Jaime Barrera *, Bernardo Giraldo, Maria Hernandez, Orlando Martinez, J Vitar

The development of Plukenetia Volubilis L. depends on its physiology and its relationship with the environment; therefore, this study aimed to determine the response to changes in light intensity and the effect of water availability in the soil on the rate of photosynthesis in P. volubilis . Seedlings were propagated with seeds and grown in bags under normal environmental conditions. The plants were subjected to two water treatments: half of the plants had irrigation with normal environmental conditions and the other half was irrigated every five days for six weeks. The available water was calculated with volumetric humidity values obtained with an ECH2O EC-5 sensor. The photosynthetic light response curve showed that this species has a high capacity for light incidence since there was no photoinhibition. There was also a tolerance to drought that allows this species to subsist for several weeks with a reduced water level (0.033 m3/m3), as indicated by significant differences in the PSII and the Fv/Fm ratio, which is understood as photoinhibition until the sixth week of water stress under normal environmental conditions. The results showed that this species is adaptable to drought, is resistant to water deficits, and has an opportune photoinhibition mechanism reaction that prevents the photosynthetic apparatus from being damaged. This preliminary results support the species inclusion in agroforest model to provide productive solutions in the reconversion areas of the Amazonian Colombian region.