Alternative substrates to fern tree fiber in the production of ornamental bromeliad

O objetivo deste trabalho foi avaliar substratos alternativos para o cultivo da bromélia Aechmea fasciata (Lindley) Baker, para substituir com efi ciência as misturas formuladas com o xaxim Dicksoniasellowiana (Presl.) Hook. Foram testados os substratos: casca de Pinus, casca de Eucalyptus, coxim, fi bra de coco e xaxim, misturados com turfa e perlita, nas proporções 2:7:1, 5:4:1 e 8:1:1. O experimento foi realizado em condições de estufa com cobertura de polietileno, sombreada com tela a 70%. As bromélias foram cultivadasdurante 435 dias, até o início do fl orescimento – estádio de comercialização. As variáveis analisadas foram as massas de matéria seca de: folhas, raiz, infl orescência, escapo fl oral e caule; além da massa de matéria seca total e a qualidade comercial. Os substratos formulados com xaxim ou casca de Pinus, nas proporções 2:7:1,5:4:1 e 8:1:1, e com casca de Eucalyptus, fi bra de coco ou coxim, na proporção 2:7:1, foram as misturas que apresentaram os melhores resultados. Os substratos formulados com casca de Eucalyptus, fi bra de coco ou coxim, com 10% de turfa e 10% de perlita, na proporção 8:1:1, apresentaram os piores resultados.The objective of this study was to evaluate alternative substrates for the cultivation of the bromeliad Aechmea fasciata (Lindley) Baker, to substitute the formulated mixtures with fern tree fi ber from Dicksoniasellowiana (Presl.) Hook. Tested substrates were: Pinus bark, Eucalyptus bark, coxim (made of coconut fi ber), coir or fern tree fi ber, mixed with peat and perlite, in the proportions 2:7:1, 5:4:1 and 8:1:1. The experiment was conducted in a greenhouse covered with polyethylene and shaded with shade cloth 70%. The bromeliads werecultivated during 435 days, until the beginning of the fl owering, when they were suitable for commercialization. The evaluated parameters were dry masses of leaf, root, infl orescence, fl oral scape, and stem, besides total dry mass and the commercial quality. The substrates formulated with fern tree fi ber or Pinus bark, in the proportions 2:7:1, 5:4:1 and 8:1:1, and with Eucalyptus bark, coir or coxim, in the proportion 2:7:1, showed the best results. The substrates formulated with Eucalyptus bark, coir or coxim in the proportion 8:1:1 presentedthe poorest results

Nitrogen use efficiency as a tool to evaluate the development of ornamental cacti species

Nitrogen efficiency, along with associated indexes, is a widely used tool for assessing nutritional status in agricultural species. However, this parameter is not used in studies with ornamental plants, especially epiphytic cacti species. In particular, we know very little about the potential response of ornamental cacti to N absorption and use. Therefore, this study aimed to evaluate N use efficiency (NUE), along with its associated parameters, in three species of ornamental cacti under nitrogen nutrition. To accomplish this, Rhipsalis baccifera, Rhipsalis paradoxa and Hatiora salicornioides were fertilized by Hogland and Arnon nutrition solution modified and enriched with urea in the concentrations of 0, 33.3 or 66.6 mM N during 180 days. At the end of the experiment, efficiency indexes were calculated. Efficiency parameters varied according to species. R. baccifera presented the greatest dissimilarity among the species, with highest uptake efficiency (NUpE), but lowest use efficiency (NUtE) and biomass conversion (BCE). R. paradoxa presented high values for NUE, NUtE, BCE and physiological efficiency (NPE) at concentrations of 33.3 mM N, suggesting greater investment in biological processes with lower supply of N. H. salicornioides had the highest averages in most parameters measured. Our results show that these indexes provided important comparative baseline information on nutritional status and investment strategy, thus serving as a suitable analytical tool to increase knowledge about this group of ornamental plants

Efeitos de diferentes concentrações de nitrogênio no crescimento de Aechmea blanchetiana (Baker) L.B. Sm. cultivada in vitro

O presente trabalho teve como objetivo avaliar os efeitos nutricionais de diferentes concentrações de nitrogênio (7,5; 15; 30; 60 e 120 mM) no crescimento de plântulas de A. blanchetiana cultivadas in vitro. Concluiu-se que 7,5 mM de nitrogênio no meio líquido de Murashige & Skoog (MS) modificado foi a concentração ótima para a maior produção de massa fresca e seca