Phenological patterns of six Xylopia (Annonaceae) species in Central Amazonia

The phenological patterns of six Xylopia species occurring in different vegetation types in the vicinity of Manaus, Central Amazonia, were studied. The observation period extended from August 1992 to July 1994. The data were recorded at biweekly intervals or at shorter intervals during the flowering season. Phenological parameters registered were flower buds, flowers, fruits, and young leaves. X. aromatica showed continuous flowering, at least at the population level. Individuals with flower buds, flowers, young and ripe fruits were found all the year round. Young leaves were also produced continually. X. amazonica showed only a three-months flowering period in the year, which coincided with the low rainfall season. The fruits ripened synchronously about six or seven months after flowering. Young leaves flushed around the year. X. benthamii flowered once a year, also within the low rainfall period. Flowering lasted around five months, beginning at the end of June and finishing at the end of October; fruits could be observed from October to February. X. crinita had an annual period of flowering that began when rainfall diminished. Flowering lasted about three months, starting in March and ending in May. The fruits of a season were ripe only in the next flowering season. X. excellens flowered once a year In the rainy season. The flowering period lasted for about three months, beginning at the end of September and ending in December. Fruits were found up to April and occasionally up to May in some of the individuals. X. emarginata was observed flowering only once in a three-year period; flowering lasted about two months showing a supra-annual pattern.