Acclimatization of micropropagated Heliconia bihai (Heliconiaceae) plants

Abstract

To evaluate the behavior of micropropagated heliconia seedlings during the acclimatization process using different substrates and shade levels, seedlings of H. bihai (Lobster Claw I) were planted in plastic trays using the substrates: washed sand, vermiculite (medium texture), and PlantMax ® Horticultura, and shade cloths with percentages of 0% (full sun), 30%, 40%, 50%, 60%, 70%, and 80% of shade in relation to full sun. Best results were obtained for washed sand and PlantMax substrates at shade conditions starting from 50%, especially at 70% and 80%. Pre-existing roots from in vitro rootings were not functional, not presenting secondary roots, and showing root tissue necrosis. Acclimatized seedlings developed new roots. This finding suggests that this plant can be acclimatized without going through a laboratory rooting stage. Key words: Heliconia, ex vitro culture, rooting ACLIMATIZAÇÃO DE MUDAS MICROPROPAGADAS DE Heliconia bihai (HELICONIACEAE)RESUMO: A cultura da helicônia é a que apresenta maior crescimento entre o cultivo de flores tropicais para a exportação. Avaliou-se o comportamento de mudas de helicônias micropropagadas no processo de aclimatização, em diferentes substratos e níveis de sombreamento. Foram plantadas mudas de H. bihai (Lobster Claw I) em bandejas plásticas contendo os diferentes substratos: areia lavada, vermiculita (textura média) e PlantMax ® Horticultura. Na avaliação de níveis de sombreamento foi utilizado o telado (sombrite), com ordem de sombreamento 0% (pleno sol), 30%, 40%, 50%, 60%, 70% e 80%. O desempenho foi superior nos substratos areia lavada e PlantMax ® Horticultura e nas condições de sombreamento a partir de 50 %, em especial 70% e 80%. As raízes pré-existentes, oriundas do enraizamento in vitro, mostraram-se não funcionais, sem a emissão de raízes secundárias e apresentando necrose do tecido radicular. As mudas aclimatizadas desenvolveram novas raízes, o que sugere que esta cultura pode ser aclimatizada sem que as plântulas passem pela fase de enraizamento em laboratório. Palavras-chave: Helicônia, cultura ex vitro, enraizamento

Slow-grown in vitro conservation of Heliconia champneiana cv. Splash under different light spectra

“…In the acclimatization of Heliconia bihai cv. Lobster Claw, explants propagated in vitro, Rodrigues et al (2005) reported greater efficiency in the process of acclimatization in a greenhouse with shade as beginning at 50 %, attaining a peak in efficiency of 80 %. The results obtained in the acclimatization trial from all the plants of all the treatments evaluated were 100 % of the plants acclimatized in the conditions proposed in P1.…”

“…The data obtained were submitted to an analysis of variance in the split-plot arrangement, and the mean values were compared by Tukey test at a 5 % level of significance (Statistical Analysis System) between the treatments proposed and between each time period evaluated. After the evaluations of each time period, the plants were acclimatized in 24-cell trays, using the commercial substrate "BASE Horticultura", and were maintained in the greenhouse with 80 % shade (Aluminet) and relative humidity of 90 % for seven days (Rodrigues et al, 2005), to evaluate the plant survival, expressed in percentage terms.…”

Cloning: Plants – Micropropagation/Tissue Culture

“…In separate studies, when different levels of shade or light were tested, survival of Heliconia bihai (lobster claw) was highest (490%) under the highest levels of 70% or 80% shade (Rodrigues et al, 2005). In vitro leaves are shade leaves because they develop under approximately 35-80 mmol m −2 s −1 and are therefore poorly adapted to sunlight.…”

Influence of Plantlet Age and Different Soilless Culture on Acclimatization of Stemona curtisii Hook.f.

“…This result indicated that the survival rate and growth of plantlets were affected by the different soilless cultures or growing media, which was in accordance with the report by Albaho et al (2009) and Kurtar et al (2010). In Heliconia bihai, the high survival rate of plantlets was found in sand and PlantMax substrates but low in vermiculite (Rodrigues et al, 2005). Nhut et al (2004) reported that the survival rate, plant height and leaves number of Colocasia esculenta plantlets cultivated in hydroponic were higher than those in soil culture.…”

“…However, there are many factors which could affect the plantlets under greenhouse e.g. planting bed or substrate, plantlet age and shading level (Rodrigues et al, 2005;Hassanpanah and Khodadadi, 2009). Padilla et al (2003) reported that the survival rate of Prunus domestica plantlets was affected by the shoot height rather than the number and length of roots.…”