Effect of supplementary irrigation on the transpiration and reproductive development of oil palm trees during the dry season in Tabasco, Mexico

Some oil palm production zones have periods of low rainfall, eliciting to water stress and impacting yields. The objective of this study was to evaluate the effect of the supplementary irrigation application during the dry season, on the water use and the transpiration of oil palm trees, and on morphological changes that occur during the different phenological stages. The monitored site was an oil palm plantation in Jalapa, Tabasco, Mexico (17° 38 N; 92° 56 W; altitude 20 m). There, the plant density is 143 palms ha−1. Two areas of palm trees with ages of 6 and 11 years were located. The soil type was classified as Gleysol. A weather station was placed in a pasture adjacent (1 km) to the plantation. The variables, evaluated from April 1 to June 23, 2017, included the structural characteristics of the plantation, sap flow, transpiration, and the morphological changes at the different phenological stages, which were assessed based on the BBCH scale. The results showed that the water use per palm tree (102–140 kg day−1) and the transpiration (1.59–2.11 mm day−1) were not significantly different among palm trees ages. The application of irrigation during the dry season maintained transpiration in palms of both ages and favoured inflorescence development and fruit formation by shortening the number of days it took the palm plants to reach fruit formation stage (stages 503-700), but increased the number of days required by the bunches to reach maturation (stages 709 to harvest). This study conducted during few months needs to be confirmed by longer term monitoring.