This study has aimed to carry out the description of fruits and seeds and germination process of desert rose, from two years of observations. The fruits and seeds were characterized based on length, diameter and number of seeds per fruit. The seeds internal structure and germinating process were also described. Germination test was performed at 25 and 30 °C temperatures, determining the germination percentage and germination speed index. Seeds harvested in 2013 were stored for 12 months and submitted to a new germination test. Parallel to these tests, the seeds imbibition curve was determined in substrates over and between sheets of paper at 15, 20, 25 and 30 °C temperatures. The fruits and seeds had similar lengths and diameters in both years of observations. The seeds can be stored for up to 12 months without loss in viability and temperatures of 25 and 30 °C are suitable for performing the germination test of this species. The water absorption curve of desert rose seeds follows a triphasic pattern of soaking.

ResumoAs temperaturas ótimas para a germinação de sementes de cactos variam com a espécie. AbstractThe optimum temperature for germination of cacti vary with the species. With this work, we aimed to evaluate the seeds germination of pitaya genotypes under different temperatures. The used genotypes were: Hylocereus undatus (PB), H. polyrhizus (PV), Selenicereus megalanthus (PA), H. undatus x H. costaricensis (PH1) and H. costaricensis x H. undatus (PH2). For each genotype we used four replicates of 50 seeds, in a completely randomized design. The sowing was carried out on blotter paper in boxes type Gerbox ®, maintained at temperatures of 15, 20, 25, 30 and 35 o C constant and 15-25, 20-30 and 25-35 o C alternating with photoperiod 12 hours. The test lasted 30 days which were appraised the

Over the past decade the desert rose received fame in the flower market due to its striking and sculptural forms; however, the commercial production of these species is quite recent and little is known about its crop management, including substrates recommendation. The objectives of this study were to investigate the effect of different substrates on desert rose seed germination and production of its seedlings. Experiment I: freshly harvested seeds of desert rose were sown in different substrates e.g. sand, coconut fiber, semi-composted pine bark, sand + coconut fiber, semi-composted pine bark + sand and coconut fiber + semicomposted pine bark. These substrates were evaluated to study the emergence percentage of seeds, initial growth of seedlings and seedling emergence speed index (ESI). Experiment II: desert rose from the experiment I were transferred to plastic pots filled with the same substrates as in experiment I. The pH and electrical conductivity (EC) of the substrates were noted every 30 days while the growth parameters of seedlings were recorded after 240 days. Results from experiment I showed higher germination rate and seedling growth in substrates containing semi-composted pine bark. Similarly, in experiment II, better quality seedlings were observed in substrates containing semi-composted pine bark. Thus, for desert rose seed germination and seedling growth, it is recommended to use substrates containing semi-composted pine bark.

In the past decades, desert rose has become a very popular ornamental plant, especially among collectors, due to its exotic and sculptural forms. However, it has been grown on a commercial scale only recently, and little is known about how to best manage it as a container-grown plant, or even which potting medium (substrate) to recommend. Therefore, the aim of this study was to investigate the interactions between potting media and irrigation levels for growing desert rose as a potted ornamental plant. The experiment was conducted in a greenhouse using a 6 x 2 factorial arrangement with six replications, six potting media and two irrigation levels. The mixes were characterized by measuring their physical properties, specifically the density and water retention capacity (WRC), as well as chemical properties, such as the pH and electrical conductivity (EC). After 210 days, plant growth and plant water consumption were evaluated and measured. A lower dry density for the vermiculite mixes was observed in comparison to that for the sand mixes. However, WRC ranged from 428 to 528 mL L-1 among the mixes, values considered close to ideal. In general, plant growth exhibited higher increases in mixes consisting of coconut fiber + sand or vermiculite, regardless of the irrigation level. Mixes of vermiculite + coconut fiber and sand + coconut fiber can be used to grow desert rose in pots, as long as irrigation is used to maintain the moisture content of the potting medium (mix) between 60-70% and 80-90% of the WRC.

RESUMO:As orquídeas do gênero Vanda são apreciadas pela exuberância de suas floradas e, diferentemente de outras orquídeas, essas plantas, de crescimento lento e monopodial, não apresentam brotações laterais que dão origem a novas mudas, características estas que lhes conferem alto valor de mercado. Então, para produzi-las em escala comercial, é preciso recorrer às técnicas de propagação in vitro, em que o meio de cultura adequado é um dos fatores mais importantes para o desenvolvimento das plântulas. Plântulas de Vanda tricolor, aos 150 dias de idade, foram subcultivadas em meio MS e meios de cultura à base de fertilizantes comerciais, com e sem adição de polpa de banana 'Nanica' (100 g L -1 ). O delineamento experimental adotado foi o inteiramente casualizado, composto por 12 tratamentos e seis repetições, com sete plântulas. Aos 180 dias, avaliaram-se as variáveis: área foliar; número de folhas e raízes; comprimento médio do sistema radicular e a matéria seca das folhas, raízes e total. Conclui-se que é possível utilizar o meio simplificado à base de fertilizante Biofert ® (08-09-09) acrescido de polpa de banana em substituição ao meio MS para o desenvolvimento in vitro de V. tricolor.

-Addition of Silicon (Si) to culture media has been shown to improve the development of seedlings grown in vitro, and to reduce losses during the acclimatization phase. The objective of this study was to evaluate the in vitro growth of Cattleya forbesii (Orchidaceae) in MS medium containing five different concentrations of SiO 2 (0.0, 0.5, 1.0, 1.5, and 2.0 g·L −1 ). At day 200, the following variables were measured: number of roots, average length of the root system, leaf area, number of leaves and shoots, shoot height, fresh and dry masses of roots and shoots, water content of roots and shoots, and pH of the culture medium. Most variables decreased as the concentration of Si increased, reducing the in vitro vegetative growth of C. forbesii. Accumulation of Si in leaf tissues was detected by scanning electron microscopy, confirming uptake by plants.The Si source and concentrations tested showed no beneficial effect on in vitro growth of C. forbesii.Keywords: Micropropagation, Culture medium, Amorphous silica. SILÍCIO NO DESENVOLVIMENTO IN VITRO DA ORQUÍDEA Cattleya forbesiiRESUMO -A adição de silício (Si) aos meios de cultura tem apontado melhor desenvolvimento das plântulas cultivadas in vitro e redução das perdas durante a fase de aclimatização. Objetivou-se avaliar cinco concentrações de SiO 2 (0,0; 0,5; 1,0; 1,5 e 2,0 g·L −1 ) em meio de cultura MS sobre o crescimento in vitro da orquídea Cattleya forbesii. Aos 200 dias, avaliou-se as variáveis: número de raízes, comprimento médio do sistema radicular, área foliar, número de folhas e de brotos, altura da parte aérea, massa fresca e seca de raízes e de parte aérea, conteúdo de água das raízes e da parte aérea, e pH final dos meios de cultura. Para a maioria das variáveis avaliadas observou-se decréscimo em função do aumento da concentração de Si, reduzindo o desenvolvimento vegetativo in vitro da C. forbesii. Além disso, detectou-se acúmulo de Si nos tecidos foliares por meio da microscopia eletrônica de varredura, confirmando a absorção deste pelas plântulas. Para o crescimento in vitro da espécie estudada, a fonte e concentrações de Si testadas, não apresentaram efeito benéfico.Palavras-chave: Micropropagação. Meio de cultura. Sílica amorfa. ________________ *

Commercial fertilizers and banana pulp for in vitro cultivation of a Phalaenopsis hybridThe in vitro propagation of orchids is a largely used procedure for the production of seedlings. The search for alternative culture media with this purpose has been widely studied due to the complexity of the commonly used media, e.g. the MS medium. The hybrids of Phalaenopsis are among the most commercialized orchids in the world due to the longevity and distinct beauty of its flowers. The objective of this study was to evaluate the effect of commercial fertilizers' formulations and the addition of 'Nanica' banana pulp in a culture medium for in vitro cultivation of a hybrid of Phalaenopsis. Seedlings germinated in vitro, in MS medium, were subcultivated in culture media with a basis of commercial fertilizers and MS medium modified with half the concentration of macronutrients. The culture media were evaluated with and without the addition of the banana pulp (100g L -1 ) during the stage of maturation 4. The basis of these culture media was composed of sucrose (30g L -1 ), activated charcoal (1g L -1 ) and agar (9g L -1 ). After 180 days the following variables were analyzed: leaf area, number of leaves and roots, root length and dry weight of leaves and roots. We were able to conclude that the treatment composed by Biofert® supplemented with banana pulp presented the best results for the hybrid development in vitro, and actually presented statistically superior results in relation to MS without banana.

The in vitro propagation techniques are commonly used to produce ornamental pineapple seedlings in commercial scale, aiming to attend the growers with genetic and sanitary quality seedlings. However, the choice of the ideal substrate is essential for the acclimatization and growth stage of the seedlings propagated by this technique, since some substrates can increase the seedling mortality and/or limit the seedling growth due to its physical and chemical characteristics. Thus, the aim of this study was to evaluate the acclimatization of ornamental pineapple [Ananas comosus (L.) Merr. var. ananassoides (Baker) Coppens & Leal] on different substrates. Seedlings with approximately seven centimeters, obtained from in vitro culture, were transplanted into styrofoam trays filled with the following substrates: sphagnum; semi-composed pine bark; carbonized rice husk; sphagnum + semicomposed pine bark; sphagnum + carbonized rice husk; and semi-composed pine bark + carbonized rice husk. Each treatment was replicated five times using 10 plants. At 180 days, there were evaluated the following variables: survival percentage, plant height, number of leaves, leaf area, largest root length, and shoot and root dry matter. The substrate semi-composed pine bark + carbonized rice husk presented the lowest mean (62%) for survival percentage. The semi-composed pine bark and semi-composed pine bark + carbonized rice husk treatments presented significant increments in some evaluated biometric characteristics. The semi-composed pine bark is the most favorable substrate for the A. comosus var. ananassoids acclimatization. Keywords: Ananas comosus var. ananassoides, Bromeliaceae, propagation, potting media. RESUMO Aclimatização e crescimento de mudas de abacaxi ornamental em substratos orgânicosTécnicas de propagação in vitro são utilizadas visando produzir mudas de abacaxi ornamental em escala comercial, a fim de atender os produtores com mudas de qualidade genética e sanitária. Porém, a escolha do substrato ideal é essencial na etapa de aclimatização e crescimento das mudas propagadas in vitro, visto que alguns substratos podem proporcionar a mortalidade das plântulas ou limitar o crescimento das mudas, devido às suas características físicas e químicas. Assim, objetivou-se avaliar a aclimatização do abacaxi ornamental [Ananas comosus (L.) Merr. var. ananassoides (Baker) Coppens & Leal] em diferentes substratos. Plântulas com aproximadamente 7 cm, oriundas de cultivo in vitro, foram transplantadas em bandejas de isopor contendo os seguintes substratos: esfagno, casca de pinus semi-compostada, casca de arroz carbonizada, esfagno + casca de pinus semi-compostada, esfagno + casca de arroz carbonizada e casca de pinus semi-compostada + casca de arroz carbonizada. Cada tratamento foi constituído de cinco repetições contendo dez plantas cada. Aos 180 dias avaliou-se as variáveis: porcentagem de sobrevivência, altura da planta, número de folhas, área foliar, comprimento da maior raiz, e massa seca da parte aérea e raízes. O substrato ca...