Storage and in vitro germination of orchids (Orchidaceae) seeds from Atlantic Forest – Brazil

Abstract

The orchid seed banks of Atlantic Forest may be considered a key strategy for the conservation of species threatened with extinction by indiscriminate collection or habitat destruction. The aim of this study was to evaluate the seed viability, to choose the best culture medium for the asymbiotic germination and evaluate germination, after storage for different periods and temperatures for the Brazilian native orchids: Gomesa praetexta (rchb.f.) M.W.Chase & N.H.Williams, Gomesa forbesii (Hook.) M.W.Chase & N.H.Williams, Gomesa recurva r.Br. and Grandiphyllum divaricatum (Lindl.) Docha Neto. Knudson C (KC), Murashige & Skoog (MS), half-strength MS (1/2 MS macro-and micro-nutrients) and Woody Plant Medium (WPM) culture media were tested for germination. The WPM culture medium was the best for asymbiotic germination of all species evaluated, with high germination percentages and improved seedling development. Seeds of G. divaricatum, G. praetexta, G. recurva and G. forbesii indicated orthodox behavior, with high viability rates after 12 months of storage, being recommended the storage temperature of-80°C for the first three species and-20°C for G. forbesii. The protocol developed in the present study was efficient for seed bank storage, in vitro germination and seedling production of G. divaricatum and G. praetexta, contributing to conservation strategies of these species.

Impact of Germination on the Microstructural and Physicochemical Properties of Different Legume Types

“…The use of the stereo microscope made it possible to highlight the changes in legume profiles: increase in volume due to water absorption, degradation of the outer layer, the appearance of the radicle, root and plumule depending on legume type. The determinations were made taking into account the procedure described in the literature [89,90]. All these transformations were correlated with the determination of the size of the constituent parts of the germs (radicle and plumule), using a Modelcraft Vernier Caliper of 125 mm.…”

Establishment of a Rapid Breeding System for Bletilla Striata

“…The basic ingredients of the growth media can provide plants with the nutrients they require for survival; however, the plants grow robustly only when these nutrients work in conjunction with the appropriate plant hormones (Franceschi et al 2019). Therefore, the selection of hormones and the combination of appropriate concentrations were key factors for the success of plant tissue culturing, and also an important breakthrough for the rapid proliferation of plants (Nie et al 2016).…”

Avaliação Da Resistência Do Solo a Penetração Sob Mata Nativa Em Um Latossolo Amarelo Distrófico No Estado Do Piauí

“…Cattleya walkeriana Gardner é uma orquídea endêmica do Brasil, representando umas das espécies ameaçadas de extinção na natureza (CNCFLORA, 2012). O elevado valor ornamental da espécie a torna alvo de coletas irregulares, o que aliado à redução de seu habitat e consequentemente de seus hospedeiros, contribui para a redução das populações naturais (FRANCESCHI et al, 2019;MENEZES, 2011).…”

“…Dentre os meios tradicionais e mundialmente utilizados na propagação in vitro de espécies de orquídeas destacam-se os meios Knudson C (KNUDSON, 1946), meio MS (MURASHIGE e SKOOG, 1962) e o meio Vacin e Went (VACIN e WENT, 1949) (FRANCESCHI et al, 2019FERREIRA et al, 2016).…”