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

The phenological patterns of six Xylopia species occurring in different veg etation types in the vicinity of Manaus, Central Amazonia, were studied. Th e 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, frui ts, and young leaves. X. aromatica showed continuous flowering, at least at the population level. Individuals with flower buds, flowers, young and rip e fruits were found all the year round. Young leaves were also produced con tinually. X. amazonica showed only a three-months flowering period in the y ear, which coincided with the low rainfall season. The fruits ripened synch ronously about six or seven months after flowering. Young leaves flushed ar ound the year. X. benthamii flowered once a year, also within the low rainf all period. Flowering lasted around five months, beginning at the end of Ju ne and finishing at the end of October; fruits could be observed from Octob er to February. X. crinita had an annual period of flowering that began whe n rainfall diminished. Flowering lasted about three months, starting in Mar ch and ending in May. The fruits of a season were ripe only in the next flo wering season. X. excellens flowered once a year In the rainy season. The f lowering period lasted for about three months, beginning at the end of Sept ember and ending in December. Fruits were found up to April and occasionall y up to May in some of the individuals. X. emarginata was observed flowerin g only once in a three-year period; flowering lasted about two months showi ng a supra-annual pattern.