Physiological and agronomic behavior of commercial cultivars of oil palm (Elaeis guineensis) and OxG hybrids (Elaeis oleifera x Elaeis guineensis) at rainy and dry seasons

Abstract

Oil palm is the most productive and efficient oilseed crop in the world. Oil palm is planted in various geographical areas, where the frequency of extreme weather events is expected to increase because of climate change. The characterization of the response of oil palm cultivars to climatic conditions will allow identifying sources of tolerance to different types of stress caused by climate change, leading to the determination of the best genotype x environment relationships. The physiological responses, oil quality and yield of 11, six-year-old commercial oil palm cultivars with different origins were evaluated in two periods of contrasting climate conditions (rainy and dry seasons between the years 2008 and 2010). We found that the first impact of a period with water deficit was the reduction on gas exchange of all cultivars. Photosynthesis fell between 25% to 40% and transpiration decreased between 10% and 50%. During the dry season, leaf sugar concentration increased respect to the rainy season between 14% to 114%, and certain cultivars showed up to 27% higher photosynthetic water use efficiency. This variation could be due to the genetics of different cultivars. No significant differences were observed between the seasons in terms of oil quality. In general, changes in oil palm physiology observed in response to water deficit were related to the ability of the palm to adapt and survive periods of drought stress. The cultivars evaluated showed a good response to dry periods, with the IRHO being the most outstanding at each evaluated season .