Flowering and fruiting phenology of Normanbya normanbyi (W. Hill) L. H. Bailey (Arecaceae), a palm endemic to the lowland tropical rainforest of north-eastern Australia

Morphoanatomy of the flower of Syagrus inajai (SPRUCE) Becc. (Arecaceae- Arecoideae- Attaleinae), Amazon

The occurrence of Syagrus inajai (Spruce) Becc., popularly known as pupunha palm, among other names, has been registered in the Guianas and in the North of Brazil in areas of terra firme (non-flooding) and gallery forests. In order to characterize the inflorescence and further knowledge of this family, a morphoanatomical study was carried out of the palm S. inajai in a green area of the Campus of the Federal University of Amazonas--UFAM, Manaus, Amazonas. The inflorescences are branched to one order, pedunculate, and interfoliar, measuring 62-82 cm in length, with woody bracts with longitudinal grooves on the external surface, and flowers in triads. The number of flowers to each inflorescence varies from 5,904 to 17,316 for staminate flowers, and from 180 to 3,528 for pistillate flowers. Staminate flowers with six anthers and one vascular bundle each; three-lobed pistillodium, vascularized pistillodium. Its pistillate flowers have six staminodia joined to form a circle, syncarpic, tricarpellary, trilocular gynoecium, one ovule to each locule, synascidiate in the ovary, and plicated above. Tripartite stigma, apical and sessile, with epidermis composed of elongated papillary cells, pattern of epidermis that is maintained throughout the stylar canal. Bitegmented, anatrope, pachychalazal ovule.

Analysis of a supra-annual cycle: reproductive phenology of the palm Oenocarpus bataua in a forest of the Colombian Andes

During a 4-y study of the palm Oenocarpus bataua, 368 reproductive structures on 102 palms were monitored. A reproductive structure required nearly 2 y for successful completion, from bud to ripe fruit. We found correlations with summed rainfall and averaged relative humidity and/or solar radiation for initiation of bud appearance, flowering and fruit maturation over 0–4 mo prior to the events, and another set of correlations over longer periods up to 11–12 mo before. Climatic variables showing short-term correlations (apparently triggering an event) often differed from those showing long-term correlations (which presumably initiated developmental processes culminating in the event itself). A high degree of asynchrony occurred in production of reproductive structures both within and between individual palms even within major reproductive peaks, and there were pronounced differences between individuals in total reproductive effort. Nearly all palms passed 1–3 y with little or no reproduction despite similar environmental conditions between years. We conclude that the supra-annual cycle of this palm is not the result of inadequate environmental cues in some years. There appear to be at least two different types of supra-annual cycles in tropical plants, differing in the relative importance of extrinsic cues vs. intrinsic physiological rhythms and in intrapopulation synchrony.