Abstract

FERNANDEZ M., Ginna Esperanza; MELGAREJO, Luz Marina  and  RODRIGUEZ C., Natalia Alejandra. Some aspects of the photosynthesis and water potentials in the reproductive phase of sweet granadilla (Passiflora ligularis Juss.) in Huila, Colombia. rev.colomb.cienc.hortic. [online]. 2014, vol.8, n.2, pp.206-216. ISSN 2011-2173.

The sweet granadilla fruit is appreciated in the national and international markets for its organoleptic and nutritional characteristics. However, very few studies have been done on its ecophysiology in the high-production areas of Colombia. Therefore, the aim of this study was to describe and analyze some aspects of the photosynthesis and water potentials of sweet granadilla in the production phase on two farms located in the municipality of Santa María (Huila, Colombia): La Ceiba (2,060 m a.s.l.) and La Yerbabuena (2,270 m a.s.l.). The climatic variables were monitored and the parameters of gas exchange, chlorophyll a fluorescence and water potentials were measured. The average temperature in La Yerbabuena was 16.24°C and, in La Ceiba, it was 17.15°C, with a PAR of 470.9 and 1,186.2 mmol photons m^-2 s^-1, respectively. The values A_max, R_D and I_c for La Ceiba (23.6, 2.24 and 34.6 mmol m^-2 s^-1) were higher when compared to La Yerbabuena (17.5, 1.34 and 21 mmol m^-2 s^-1); the latter showed a high capacity to use available light to ensure a greater photosynthetic efficiency (F) of 0.0457 at low values of radiation. The water potential in the leaves (close to -0.2 MPa) and soil (near -0.01 MPa) and the Fv/Fm value (above 0.86) during the predawn indicated the absence of stress in the plants. In conclusion, both environments were favorable for the development of sweet granadilla because, despite the environmental characteristics and the different light intensities, a highly efficient photosynthesis (F) was maintained.

Keywords : photosynthetic rate (A); photosynthetically active radiation (PAR); efficient use of extrinsic water (WUEe); stomatal conductance (g_s).

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )