Water stress and morphogenesis in mango.
Pire R., Rojas E.
Author Affiliation: Universidad Centroccidental Lisandro Alvarado, Apartado 400, Barquisimento, Lara, Venezuela.
Proceedings of the Interamerican Society for Tropical Horticulture 39 : 145-150
Abstract : In trials carried out in 1994 and 1995, 2- and 3-year-old mango cv. Haden trees were cultivated in 20-litre containers at 4 different drought stress levels. Watering frequency varied from every 2-3 days in the wettest treatment to every 14-20 days in the driest. After 5 weeks, all plants were irrigated on alternate days with 3 litres of water each. Substrate humidity, plant water status, leaf area, plant height and gas exchange were measured just before restarting watering, while vegetative and floral shoot production were monitored during the next 3 weeks or so. In the 2-year-old plants there was no flowering even 20 days after watering restarted, possibly due to juvenility, but buds were formed, increasing in number from 0.13 to 0.62 per branch as the level of drought stress decreased. In the 3-year-old plants, where the daytime water potential varied on average between -1.90 and -2.56 MPa, the same tendencies were found with respect to the formation of buds. Flowering occurred in 25% of the plants, but without a definite tendency with respect to water stress level. The results seem to confirm the fact that water stress is not a mechanism encouraging the formation of mango flowering but it does affect vegetative growth.