Tropentag 2021, September 15 - 17, hybrid conference, Germany "Towards shifting paradigms in agriculture for a healthy and sustainable future"

Ecotypical Flower Biometry in the Neotropical Oilseed Palm Acrocomia

¹University of Hohenheim, Inst. of Agric. Sci. in the Tropics (Hans-Ruthenberg-Institute), Germany
²Federal University of Viçosa, Department of Forestry, Brazil
³Federal Univerity of Viçosa, Department of Plant Science, Brazil

Abstract

The neotropical oilseed palm Acrocomia is considered a sustainable alternative to African oil palm in sub-humid tropical regions due to its high oil yield and adaptation to many diverse environments.
The inflorescences of Acrocomia are panicles with several hundred rachillae bearing female and male flowers. The female flowers are globose, sessile and spirally arranged at the basal end of the rachillae. The apical two thirds of the rachillae bear dense spirals of solitary male flowers. The inflorescences are surrounded by a bract leaf before anthesis. Acrocomia is protogynous and upon bract opening, female flowers are receptive for around 24-48 hours. Anthesis of male flowers starts 24 hours after bract opening and their abscission is initiated on the fourth day. General morpho-anatomic and biometric studies on Acrocomia flowers already provided relevant information on the reproductive biology of Acrocomia; however, differences between ecotypes were not assessed up to now. This study aimed to gain detailed knowledge on flower biometry in ecotypes of A. totai and A. aculeata originating from different climatic regions in Brazil.
The study was conducted at the Acrocomia Active Germplasm Bank of the Universidade Federal de Viçosa in Araponga, MG, Brazil. Nine rachillae from each inflorescences of five ecotypes were sampled in the flowering season of 2019. The length of the rachillae, and the number of female and male flowers were recorded. Their fresh and dry weight were measured. The height and diameters of female flowers were determined.
Acrocomia totai ecotypes showed higher numbers of small, light weighted female flowers per rachillae. A. aculeata tended to bigger and heavier female flowers but fewer in numbers per rachillae. In all ecotypes the number of female and male flowers decreased on the rachillae from the basal to the apical end of the inflorescence. However, only 17% of the rachillae had 6-8 female flowers, considered optimal for a good yield formation. Acrocomia shows a requirement for genetic improvement but also a high capacity due to a wide genotypical and ecotypical variability important for the selection of superior breeding material.

Keywords: Acrocomia aculeata, Acrocomia totai, Brazil, diversity, flower biometry, oilseed palms

Contact Address: Catherine Meyer, University of Hohenheim, Inst. of Agric. Sci. in the Tropics (Hans-Ruthenberg-Institute), Garbenstrasse 13, 70593 Stuttgart, Germany, e-mail: catherine.meyeruni-hohenheim.de