MORFOLOGIA DE FRUTO, SEMENTE E PLÂNTULA, E GERMINAÇÃO DE SEMENTES DE Myrceugenia euosma (O. BERG) D. LEGRAND (MYRTACEAE)

Abstract

ResumoMyrceugenia euosma (O. Berg) D. Legrand (Myrtaceae) tem porte arbóreo ou arbustivo, com ocorrência na América do Sul, principalmente no Chile e no sul do Brasil. Objetivou-se estudar a morfologia de fruto, semente e plântula, e a germinação de sementes desta espécie. Os frutos foram coletados de cinco matrizes em remanescente de Floresta Ombrófila Mista Aluvial em Araucária -PR. Foi testada a influência de diferentes substratos (papel, rolo de papel e areia), temperaturas (20 ºC, 25 ºC e 30 ºC) e condições de luz (presença e ausência) sobre a germinação das sementes. M. euosma tem fruto do tipo baga, contendo de 2 a 13 sementes, envolvidas por tegumento membranáceo, com endosperma mucilaginoso, evidente apenas na germinação. O embrião é mircióide, típico da subtribo Myrciinae, e a plântula é epígea, fanerocotiledonar. A germinação tem início entre três e cinco dias e, com exceção do substrato rolo de papel na temperatura 30ºC, os demais tratamentos apresentaram percentuais relativamente altos de germinação (≈ 72%). As sementes são fotoblásticas neutras. Os resultados indicam que M. euosma tem poucas restrições em termos reprodutivos quanto à germinação. Palavras-chave: Myrciinae; Floresta Ombrófila Mista; Floresta com Araucária. Abstract Morphology of fruit, seed and seedling and seed germination of Myrceugenia euosma (O. Berg) D. Legrand (Myrtaceae). Myrceugenia euosma is a tree or shruby species that occurs in South America in two major centers: Chile and south of Brazil. The objective of this work was to study the morphology of the fruit, seed and seedling and the seed germination of this species. Fruit, seed and seedling were illustrated and described. The influence of three substrates (paper towels, paper roll and sand), temperatures (20 ºC, 25 ºC and 30 ºC) and conditions of light (presence and absence) over the seed germination were evaluated. The fruit of M. euosma is a berry, containing 2 to 13 seeds. The seed has membranaceous tegument, small amount of mucilaginous endosperm, evident only in germination, and embryo typical of the subtribe Myrciinae. The seedling is epigea, phanerocotylar, with paracotyledons and eophylls simple, opposites. Germination started three to five days after the test installation. Almost all treatments resulted in relatively high germination percentage (≈72%), except in paper roll at 30ºC (43%). The species germinates in the absence of light. The results indicate that M. euosma has few reproductive restrictions with regard to germination.

Production of 'Cortibel' Group Guava Seedlings on Different Substrates

“…It was verified that the use of the Bioplant ® substrate did not favor the germination of guava seeds, even though it contained several materials in its composition. This is probably due to the high-water retention capacity, together with deficient aeration in the substrate, as the triggering of the germ process of a viable seed requires adequate environmental conditions of humidity, temperature, oxygen and, in some cases, light (Cosmo et al, 2017).…”

MORPHOLOGY, BIOMETRICS AND GERMINATIVE POTENTIAL OF Mollinedia clavigera Tul.

“…In the morphological description of seeds and seedlings, the structures are differentiated, making it possible to obtain information on germination, in addition to an understanding of the functionality of these structures in ecosystems, evidencing the potential for ecological use in conservation, environmental restoration (COSMO et al, 2017;GOMES et al, 2015) and identification of the successional stage, (GOGOSZ et al, 2015) dispersion and regeneration.…”

Seedling production of Bertholletia excelsa in response to seed origin and position inside fruit

“…To attain the minimum values of these indexes in each tree species, it is necessary to know the recipient size and volume, the correct matter management, fertilizing, and the solar radiation control (Marana et al, 2015). One of the most important ways of tree seedling production is through sexual reproduction, where germination represents a crucial phase influenced by temperature, substrate, wetness, luminosity, seed position on the seedbed, and sowing depth (Cosmo et al, 2017). Moreover, B. excelsa seeds present physiological dormancy, which results in slow, irregular, and low percentages of germination (Kainer et al, 1999a;Auca et al, 2018).…”