No abstract

ResumoO aprimoramento das técnicas experimentais do cultivo in vitro pode auxiliar em melhor identificação e multiplicação de materiais mais promissores. O objetivo desse trabalho foi a estimação do tamanho de parcelas (número de explantes) para micropropagação de videira in vitro. Foram conduzidos 15 ensaios de uniformidade formados pelas combinações de três porta-enxertos de videira com cinco diferentes meios de cultivo. Foram usados segmentos nodais com cerca 2,5 cm que foram excisados e inoculados. Após 90 dias de inoculação, foram feitas avaliações das variáveis: número de brotos, comprimento da parte aérea, a massa fresca da parte aérea e massa fresca de calos. Para cada ensaio, foram formados diversos tamanhos de parcelas, em que cada tubo, contendo um explante, foi considerado como uma unidade básica. Para a estimação do tamanho ótimo de parcela empregou-se o método da máxima curvatura modificado e as diferenças mínimas significativas entre médias foram obtidas pelo método de Hatheway. Os resultados mostraram que as estimativas do tamanho de parcela variaram de cinco (5) a 12 explantes (tubos) em acordo com a variável utilizada. Para as variáveis estudadas, o tamanho de parcela ótimo deve ser formado por 12 explantes. Palavras-chave: Vitis sp., Coeficiente de variação, tamanho de amostra, precisão experimental, ensaio de uniformidade, planejamento experimental AbstractThe improvement of experimental techniques of in vitro culture may provide better identification and multiplication of most promising materials. The aim of this study was to estimate the plot size (explants numbers) for in vitro micropropagation grape. 15 tests were conducted uniformity formed by combinations of three rootstock vine with five different culture media. Nodes segments were used with about 2.5 cm, were excised and inoculated. After 90 days of inoculation, the variables shoot number, shoot length, shoot fresh weight, and fresh weight of callus were evaluated. For each assay, was simulated plots of differents sizes, with each tube containing one explant was considered as a basic unit. For estimation the optimum plot size we used the modified maximum curvature method and the least significant difference between means was obtained by the method of Hatheway. The results showed that the estimates of the plot size ranged from five (5) to 12 explants (tubes) in accordance with the variable used. For these variables, the optimal plot size should be formed by 12 explants.

The aim of this study was to evaluate the effects of silver nitrate in the in vitro development and conservation of passion fruit plants. Experiments were carried out at the Laboratory of Culture and Tissues, in the National Cassava and Fruits Research Center (EMBRAPA), using microcuttings of Passiflora gibertii N. E. Br., previously cultivated in vitro. The microcuttings were placed in MS media supplemented with silver nitrate at concentrations of 0, 1, 2, 4 and 8 mg·L −1 , and, during 30, 60 and 90 days, the following variables were identified: Shooting length (cm), number of roots, number and coloration of leaves. A completely randomized design with 30 replications in a split-plot scheme was employed. Polynomial regression equations were adjusted in analysis of variance to compare averages of treatments. The obtained results support the assumption of high sensitivity of passion fruit tissues to ethylene, which reflects in the lost of vigor and in the induction of culture senescence by its accumulation. Based on obtained results, and in order to mitigate this problem, it is possible to indicate an addition of 2 mg·L −1 of silver nitrate in culture media, for the micropropagation of passion fruit plant, allowing the controlling of the atmosphere inside the culture test tubes, during the establishment of explants and other steps of the process.How to cite this paper: Faria, G.A., Felizardo, L

No abstract

The determination of the plot size is a practical matter pertinent to the experimental planning, and its optimal characterization allows to obtain higher precision and better quality in the results. Therefore, in this study, the main goal was to determine the plot size in experiments of passion fruit in two uniformity tests with Passiflora setacea and Passiflora alata. The experiment was constituted of a substrate at planting with 3 thirds of soil and 1 of barnyard manure. The soil was fertilizer with 3 kg of simple superphosphate and 0.5 kg of KCl by 1m³. Each species of Passiflora was considered a uniformity test with 40 basic units (BU). The evaluations of the experiments were done on 60 days after the transplant, noticing the tree's height, stem's diameter, number of leaves, number of buds, number of meristems and chlorophyll. Several plot sizes were simulated, in which each plant was first considered as a basic unit up to 40 plants per unit basic. For the estimation of optimum plot size, the maximum modified curvature method was used. The plot sizes varied with the specie, founding values as three to seven BU for Passiflora setacea and four BU to five for Passiflora alata.