Early leaf development in Euterpe oleracea Mart. (Arecaceae, Arecoideae): Leaflets, pinnae or segments?.

Autor: Pinedo, André Silva, Gomes, Sueli Maria
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Zdroj: Journal of the Torrey Botanical Society; Jul-Sep2022, Vol. 149 Issue 3, p219-229, 11p
Abstrakt: Euterpe oleracea presents long leaves with divisions in the blade frequently referred to as leaflets or pinnae, as if they were compound. The purpose of this article is to present the first leaf ontogeny study for this species. Buds of dissected E. oleracea were classified according to their size and morphology and examined under scanning electron and light microscopy. The youngest leaf primordia are conical. The first foldings in the leaf blade appear in primordia ca. 0.8 mm in length and already have procambium. When young leaves reach 1.5 mm long, these plications separate from one another. Segments change their orientation throughout leaf development. Leaf blade in E. oleracea is initially entire (nonplicate), becoming plicate at a later stage, and plications separate from each other as a final step. This developmental process has some similarities with what is observed in other palm species. According to early stages of the leaf ontogeny, these plants have simple pinnatisect and not compound pinnate leaves. The use of terminology such as "leaflets" or "pinnae" is incongruent with simple leaves, and we recommend that adult leaf blade subdivisions of Arecaceae should be called "leaf segments" instead. This work contributed to the understanding of histological changes during palm leaf development, being a contemporary report on both histological and micromorphological study on palm leaf ontogeny. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index