Biometria de sementes, morfologia da germinação e crescimento inicial de cinco Arecaceae

Abstract

Palm trees represent the third most important family for human use, after Poaceae and Fabaceae. However, some species present slow and uneven germination, hindering the production of seedlings. There are few reports on the morphological aspects of seeds, seedlings and conditions necessary to obtain high quality seedlings. The objective of this work was to obtain information on seed biometry, seedling morphology and initial growth in distinct environments of five palm species (Euterpe oleracea, Oenocarpus mapora, Carpentaria acuminata, Sabal palmetto and Sabal maritima). For seed biometry a sample of 100 seeds was used for each species, measuring the length and diameter and later histograms, frequency polygons and boxplots of these characteristics were generated. For the study of germination morphology, 100 pre-germinated seeds of each species were seeded in 288 cm³ tubes filled with vermiculite and composed in the volumetric ratio of 2:1. The events of the germination process and seedling formation were recorded through digital photos and arranged sequentially over time. For initial growth analysis the seeds were pre-treated to accelerate the germination process, where they were later sown in 12x26 cm bags. The experiment was conducted in a completely randomized design (DIC), and the factors were arranged in a plot arrangement subdivided in time with six replications (4 replicate-1 plants). The variables measured were: number of leaves, plant height, collection diameter, root length, fresh and dry weight of shoot and root and Dickson quality index. However, the respective length and mean diameter of E. oleracea seeds were 11.93 mm and 9.69 mm, O. mapora was 17.6 mm and 15.28 mm, C. acuminata was 10.02 mm and 8.29 mm, S. palmetto of 5.55 mm and 7.16 mm and S. maritima of 6.68 mm and 9.04 mm. The formats found were ovoid, globose and oblate. The germination of E. oleracea, O. mapora and C. acuminata were of the adjacent limestone type, S. palmetto and S. maritima were of the remote ligated type. The species E. oleracea and C. acuminata presented better results in the agricultural greenhouse, O. mapora and S. palmetto developed better in full sun, whereas S. maritima is indicated for both the protected environment and the full sun.