The Impact of Climatic Variability on Phenological Change, Yield and Fruit Quality of Mangosteen in Phatthalung Province, Southern Thailand

Abstract

Southern Thailand is a traditional area for tropical fruit plantations. Recently, the phenology in many fruit trees, including mangosteen, has been changed due to climatic variability. Therefore, the impact of climatic variability on phenological change, yield and quality of mangosteen needs to be investigated. In 2008, a study was established in an orchard in Phatthalung province, southern Thailand. Eighteen-year old mangosteen trees with 8 × 8 m spacing were used to investigate fl owering during the in-season, off-season and even, alternate bearing during three consecutive years (2008–2010). The 30year weather data from 1981 to 2010 showed trends of change in the annual rainfall, the number of rainy days, and the maximum and minimum temperature. A marked change in rainfall distribution affected the phenological change in fl owering, productivity and fruit quality. In 2008 and 2009, the mangosteen trees experienced the required dry period that regulates fl oral induction before fl owering. Thus, fl owering was found in both the in-season and off-season. However, in 2010, a prolonged drought in summer followed by rain during July–August caused leaf fl ushing instead of fl owering and this resulted in no off-season fruit production. This indicated that climatic variability resulted in a phenological change of mangosteen in Phatthalung province, southern Thailand where there is usually off-season production. In addition, climatic variability affected the fruit yield and fruit quality of mangosteen.