Observation on Growth and Phenology of Eurycoma longifolia in Hainan

In December 2017, purchased Eurycoma longifolia seeds were sewed in Haikou, Hainan province in non-woven containers. From February 2019 to March 2020, observations were carried out on phenology, seedling height and ground diameter of the above seedlings. The results showed that E. longifolia could grow in Haikou all year round and shoot 2-5 times, and the sprouting period was mainly from March to November. The inflorescence was terminal panicle, the flowering time was from May to July. The annual increment of seedling height was 48.72 cm, and that of ground diameter was 11.61 mm. The growth of seedling height was slow-fast-slow with one peak in November, when the net growth accounted for 21.63% of the whole year growth. The ground diameter also had one growth peak in December with the net growth accounted for 18.70% of the whole year. The seedling height and ground diameter growth had evidently negative correlation with the average monthly light intensity (P< 0.05).