A knowledge of pollen characters in early-diverging angiosperm lineages is essential for understanding pollen evolution and the role of pollen in angiosperm diversification. In this paper, we report and synthesize data on mature pollen and pollen ontogeny from all genera of Nymphaeales within a comparative, phylogenetic context and consider pollen evolution in this early-diverging angiosperm lineage. We describe mature pollen characters for Euryale, Barclaya, and Nymphaea ondinea, taxa for which little to no structural data exist.
Oil palm is one of the most productive oil-producing crops and can store up to 90% oil in its fruit mesocarp. Oil palm fruit is a sessile drupe consisting of a fleshy mesocarp from which palm oil is extracted. Biochemical changes in the mesocarp cell walls, polyamines, and hormones at different ripening stages of oil palm fruits were studied, and the relationship between the structural and the biochemical metabolism of oil palm fruits during ripening is discussed. Time-course analysis of the changes in expression of polyamines, hormones, and cell-wall-related genes and metabolites provided insights into the complex processes and interactions involved in fruit development. Overall, a strong reduction in auxin-responsive gene expression was observed from 18 to 22 weeks after pollination. High polyamine concentrations coincided with fruit enlargement during lipid accumulation and latter stages of maturation. The trend of abscisic acid (ABA) concentration was concordant with GA₄ but opposite to the GA₃ profile such that as ABA levels increase the resulting elevated ABA/GA₃ ratio clearly coincides with maturation. Polygalacturonase, expansin, and actin gene expressions were also observed to increase during fruit maturation. The identification of the master regulators of these coordinated processes may allow screening for oil palm variants with altered ripening profiles.