Asymbiotic culture of Cattleya intermedia Graham (Orchidaceae): the influence of macronutrient salts and sucrose concentrations on survival and development of plantlets

Abstract

Cattleya intermedia is an Atlantic Forest species endemic to Brazil that is classed as vulnerable on the list of threatened species. In this study, C. intermedia plantlets were micropropagated in an asymbiotic culture and the influence of different concentrations of sucrose (15, 30, 45 and 60 g L -1 , plus a zero sucrose medium) and macronutrient salts (complete Murashige and Skoog (MS) medium and half MS medium (with half-strength macronutrients)) on survival and development of the plantlets was evaluated. In all treatments 100% plantlet survival was achieved. The integrated analysis of height of aerial part, number of leaves per plantlet, fresh mass, number of roots per plantlet and length of the longest root showed that the plantlets exhibited greatest development at the half-strength macronutrient concentrations with 45 or 60 g L -1 of sucrose, as well as at the complete macronutrient concentration with 60 g L -1 of sucrose. Plantlets acclimatized and reintroduced to an environment in which the species occurs naturally exhibited 98.6% survival. The results obtained in this study allowed the establishment of optimal conditions for asymbiotic micropropagation, which is a requisite for future studies focused on conservation of C. intermedia.

Survival and development of reintroduced Cattleya intermedia plants related to abiotic factors and herbivory at the edge and in the interior of a forest fragment in South Brazil

“…Each germinated seed gave rise to a plant. After three months, the plants were transferred into fresh medium as described by Sasamori et al (2015). At the end of six months of in vitro culture, the plants were 4.0 ± 0.2 centimeters individual recorded during the identification of species present in areas of the Sinos River basin (A); capsule (arrow) at the end of summer (March), the period of the year in which it ripens and releases the seeds (B); plants grown in vitro after six months (C); tray for plant acclimatization and substrate fixation (D); individuals reintroduced at the forest edge that experienced leaf abscission (of leaves formed prior to reintroduction) and the formation of new shoots (E); individuals reintroduced at the forest edge wich maintained leaves formed before reintroduction (LBR), and had continuous growth and increment of the morphometric parameters from new larger shoots (LAR) (F); reintroduced plants in the forest interior, exhibiting little growth (LAR), besides being slightly shorter than those that already existed (LBR) when reintroduced (G).…”

Conservation of Vriesea flammea L.B.Sm., an endemic Brazilian bromeliad: effects of nutrients and carbon source on plant development

“…Despite the success in germination rate, the use of sterile capsules to obtain plants from seeds germinated in vitro was not very feasible since it led to a high degree of contamination of seeds by fungi and bacteria. The use of both methodologies is quite common for obtaining bromeliad or orchid plants by means of seeds (Droste et al, 2005;Pedroso et al, 2010;Suzuki et al, 2010;Soares et al, 2012;Endres Júnior et al, 2014;Sasamori et al, 2015;. Vriesea gigantea Gaudich., V. philippocoburgii Wawra and V. incurvata Gaudich.…”

“…The results recorded for V. flammea corroborate the findings made for other species of bromeliads such as Aechmea blanchetiana (Baker) L.B.Sm., A. bromeliifolia (Rudge) Baker, Alcantarea imperialis (Carrière) Harms, Nidularium minutum Mez and Vriesea incurvata, which also showed higher development of morphometric parameters when grown with low concentrations of nutrients in the culture medium (Fráguas et al, 2002;Kanashiro et al, 2007;Sasamori et al, 2016). Because it contains higher amounts of mineral nutrients than other culture media, dilutions of the original formulation of MS medium (Murashige and Skoog, 1962) have been widely used for the propagation of various plant species (Fráguas et al, 2002;Endres Júnior et al, 2014;Sasamori et al, 2015Sasamori et al, , 2016.…”

“…M.W. Chase & N.H. Williams also showed higher averages for fresh mass and aerial and root systems in treatments with higher sucrose concentration (Rego-Oliveira et al, 2003;Sasamori et al, 2015Sasamori et al, , 2018.…”

Host tree bark traits and development of reintroduced Cattleya intermedia (Orchidaceae) plants in Southern Brazil

“…Cattleya intermedia is an epiphytic Orchidaceae endemic in Atlantic Forest and is endangered at national level in Brazil and regional level in the state of Rio Grande do Sul (Martinelli & Moraes 2013;Rio Grande do Sul 2014). In vitro propagation, acclimatization, reintroduction and monitoring of populations were performed in the last decade, which provided the initial information so that the individuals used in this study could be obtained and its initial stages of development (Sasamori et al 2014(Sasamori et al , 2015Endres Júnior et al 2015).…”