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The aim of the work was to evaluate the use of substrates as support agents in substitution of agar in the medium and concentrations of 6-benzylaminopurine (BAP) in the in vitro multiplication of Oncidium baueri. Two factors were evaluated: types of substrates (rice husk, carbonized rice husk and agar) and BAP concentrations (0, 1, 2 e 3 mg L-1). After four months, it was evaluated the survival percentage; average leaves number; average sprout number; fresh and dry mass aerial part of the explants. Regarding the percentage of survival and the number of leaves, the agar showed the highest averages. For the number of shoots, the carbonized rice husk and the agar did not differ statistically. The highest fresh mass was obtained using 1 mg L-1 BAP and agar. For the dry mass, agar showed the highest average when associated to 1 mg L-1 of BAP, however, no significant difference was observed at 0 and 3 mg L-1. Thus, the use of agar and 1 mg L-1 of BAP is recommended. However, as an alternative to agar carbonized rice husk without the growth regulator, but a reduction of up to 35.8% in the survival rate and 53.8% in the number of in in vitro multiplication of O. baueri.

The objective of the research was to evaluate cytokinin concentrations and agricultural residues as physical structuring agents of the culture medium in the in vitro propagation of highbush blueberry (Vaccinium corymbosum ‘Duke’). To that end, three different concentrations of 2-isopentenyladenine (2iP) (0, 5, and 10 mg L-1)in woody plant medium (WPM) and five structuring agents (in natura rice husks, carbonized rice husks, coconut fiber, S-10 Beifort®, and agar)were tested. After 60days of culture, the following parameters were evaluated: survival (%),sprout and shoot lengths (cm),propagation rate, number of sprouts, and shoot dry mass (g). The substrates used as structuring agents were analyzed in terms of pH and electrical conductivity. The in natura rice husk, S-10 Beifort®, and carbonized rice husk did not differ from the agar in terms of the sprout length. The shoots were longer (1.64 cm) in cultures within natura rice husk than in other treatments. In the absence of 2iP, S-10 Beifort® resulted in the highest propagation rate (2.97). Concerning the number of sprouts, S-10 Beifort®, in natura rice husks, and carbonized rice husks did not differ from agar. However, when the regulator was added, the agar performed better in comparison to the other residues. Thus, in natura rice husks, carbonized rice husks, and S-10 Beifort®are potential physical structuring agents of the culture medium that can be used without 2iP. RESUMO: O objetivo deste trabalho foi avaliar concentrações de citocinina e resíduos agrícolas como agentes físicos de estruturação do meio na multiplicação in vitro de mirtileiro (Vaccinium corymbosum) ‘Duke’. Para isso, foram testadas três concentrações de 2-isopenteniladenina (2iP) (0; 5 e 10 mg L-1) no meio WPM (Wood Plant Media); e cinco agentes estruturantes (casca de arroz in natura, casca de arroz carbonizada, fibra de coco, S-10 Beifort® e ágar). Após 60 dias foram avaliados: sobrevivência (%); comprimento de brotações e de parte aérea (cm); taxa de multiplicação; número de brotações e massa seca de parte aérea (g). Analisou-se os substratos utilizados como agentes estruturantes quanto ao pH e condutividade elétrica. A casca de arroz in natura, o S-10 Beifort®, e a casca de arroz carbonizada não diferiram do ágar quanto ao comprimento de brotações. Na casca de arroz in natura obteve-se o maior comprimento de parte aérea (1,64 cm), diferindo dos demais tratamentos. Na ausência de 2iP o S-10 Beifort® apresentou a maior taxa de multiplicação (2,97). Para o número de brotações o S-10 Beifort®, a casca de arroz in natura e carbonizada não diferiram do ágar. Entretanto, quando acrescido de regulador, o ágar apresenta um desempenho maior em relação aos resíduos. Sendo assim, a casca de arroz in natura, a casca de arroz carbonizada, e o S-10 Beifort® apresentam-se como potencias estruturadores físicos do meio de cultura, podendo ser utilizados sem o uso de 2iP.

The association of different species of endophytic bacteria with the rhizosphere of the host plants can stimulate growth, development and acclimatization, offering a greater quantity of seedlings, in addition to reducing the cycle, providing economic return to the producer. The objective of this study was to evaluate the effect of introduction four bacterial isolates through inoculation into the root system in three banana cultivars (Prata Anã, Grande Naine and BRS Princesa) in the acclimatization phase. The evaluated treatments were: control (nutrient broth without bacteria); Bacillus cereus strain 1 (BC1); Bacillus cereus strain 2 (BC2); Bacillus thuringiensis (BT); Buttiauxella agrestis (BA). The morphological characteristics related to the development of the plants (total height and pseudostem diameter) were evaluated throughout the acclimatization period. After 90 days of transplanting and acclimatization, root length, leaf number, dry root weight, pseudostem and leaf, leaf area, internal carbon concentration, stomatal conductance, photosynthesis rate, transpiration rate, leaf temperature and chlorophyll were evaluated. The bacteria showed different results in relation to the studied cultivars. Considering the morphological and physiological characteristics observed in this study, B. thuringiensis for the cultivars Prata Anã and Grande Naine and the B. agrestis for the cultivar BRS Princesa are recommended for the process of acclimatization of banana seedlings, as they stimulated growth of the plant, increasing the dry mass, besides promoting the growth of roots. In this way, they improved the physiological aspects of the plants and reduced the period of acclimatization of the banana.

the aim of this study was to evaluate the chemical characteristics and sensory acceptance of juices and cuts of ‘Bordô’ and ‘Niágara Rosada’ grapes. The experimental design was in a one-factor scheme, with five levels. Treatments were: T1 – ‘Bordô’ (100%); T2 – ‘Bordô’ (70%) + ‘Niágara Rosada’ (30%); T3 – ‘Bordô’ (50%) + ‘Niágara Rosada’ (50%); T4 – ‘Bordô’ (30%) + ‘Niágara Rosada’ (70%); T5 – ‘Niágara Rosada’ (100%). Chemical analyses were: content of soluble solids, pH and titratable acidity, and sensory analyses were: color, aroma, flavor, body and global acceptance. For the soluble solids content, the highest averages were verified in T1, T2 and T3 treatments. As for pH, the highest value was recorded in T3, T4 and T5 treatments, while the highest titratable acidity was recorded in T4 and T5 treatments. In the sensory analysis, in juice with the highest percentage of ‘Bordô’ grape (T1 and T2) or with the same proportion of ‘Bordô’ and ‘Niágara Rosada’ (T3), the highest mean acceptance values were found. Thus, it could be concluded that the use of 100% ‘Bordô’ grape and ‘Bordô’ juice cut with up to 50% ‘Niágara Rosada’ are presented as alternatives for juice production.

Blueberry (Vaccinium spp.), much appreciated for its exotic flavor and nutraceutical properties, can be consumed in natura and in beverages such as nectar and juice. The aim of this study was to evaluate the chemical characteristics and the acceptance of commercial nectar and blueberry juice elaborated by the steam dragging method. The work was carried out in August of 2016, at the Universidade Federal de Pelotas, Pelotas (RS). The experimental design was in a uniform scheme, with two levels: commercial nectar and juice elaborated with the combination of fruits of cultivars Bluegem and Powderblue. Soluble solids content, titratable acidity and the pH of the samples were evaluated. For the sensorial analysis, a panel of fifty-five judges evaluated attributes such as color, aroma, flavor, body and global acceptance, using a nine-point hedonic scale. Regarding the chemical analyzes, there was a statistical difference for total soluble solids content and the nectar showed the highest content. In the sensory analysis, the juice elaborated with ‘Bluegem’ and ‘Powderblue’ obtained the highest mean for color, while for the flavor and body attributes, the preference of the judges for the nectar was verified. However, both had good overall acceptance, with scores between 7.52 and 7.62. Thus, acceptance of both nectar and juice was considered satisfactory by the evaluators.

Na micropropagacao de orquideas, a concentracao adequada de reguladores de crescimento, bem como a substituicao do agar por substratos alternativos no meio de cultura podem ser promissoras do ponto de vista da praticidade e da economia financeira para a obtencao de mudas. Assim, o objetivo do trabalho foi avaliar diferentes concentracoes de reguladores de crescimento e substratos alternativos em substituicao ao agar no meio de cultura para a multiplicacao e o enraizamento in vitro de Oncidium baueri. Na fase de multiplicacao dos explantes, foram avaliados dois fatores: concentracao de benzilaminopurina (BAP) (0,0; 1,0; 2,0 e 3,0 mg L-1) e substrato (agar, vermiculita e fibra de coco) no meio de cultura MS e, no periodo de enraizamento, foram testadas concentracoes de acido indolbutirico (AIB) (0,0; 0,5; 1,0 e 1,5 mg L-1) nos mesmos substratos e meio de cultura. Apos seis meses da instalacao dos experimentos, foram avaliadas as variaveis: porcentagem de sobrevivencia; numero medio de folhas, brotacoes e raizes; comprimento da parte aerea e da maior raiz. Para a fase de multiplicacao in vitro e necessario a utilizacao de BAP na concentracao de 1,0 mg L-1; porem, para a fase de enraizamento a utilizacao do regulador de crescimento AIB e dispensavel. Quanto aos substratos, a vermiculita nao e indicada para substituir o agar; entretanto, a fibra de coco pode ser usada, tanto na fase de multiplicacao, quanto no enraizamento in vitro de Oncidium baueri.