Revista Ciência Agronômica
URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/10361
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Item Growth and physiological quality in clonal seedlings of Robusta coffee(Universidade Federal do Ceará, 2020) Giuriatto Júnior, Jurandyr José Ton; Espindula, Marcelo Curitiba; Araújo, Larissa Fatarelli Bento de; Vasconcelos, Jaqueline Martins; Campanharo, MarcelaThe intrinsic characteristics of the vegetative propagule may influence the rooting speed and shoot growth, as well as the final physiological quality of clonal seedlings of Coffea canephora. The aim of this study was to evaluate the growth and physiological quality of ‘Robusta’ coffee seedlings produced from propagules (stem cuttings) with different cutting ages. The study was conducted in a greenhouse, in the district of Ouro Preto do Oeste, in Rondônia, Brazil (10˚45’43” S and 62˚15’10” W). The ages of the cuttings were 30, 60, 90, 120 and 150 days, corresponding to five positions on the secondary orthotropic stem (sprout), from the apex to the base. Dry matter accumulation, and relative and absolute growth rates were evaluated for 188 days after cutting, as well as the vegetative characteristics of the seedlings at 125 days after cutting. It appears that growth can be divided into three phases: 1) Initial: slow growth, lasting approximately 83 days; 2) Intermediate: fast growth, lasting approximately 40 days; and 3) Final: slow growth, starting approximately 125 days after cutting. With physiological quality, although all the cuttings showed similar growth curves, those of 60, 90 and 120 days produced, 125 days after cutting, the best vegetative performance in the seedlings.Item Alternative for the evaluation of coffee seedlings using Fisher’s discriminant analysis(Universidade Federal do Ceará, 2016-04) Campos, Katia Alves; Morais, Augusto Ramalho de; Paixão, Crysttian ArantesOne of the applications of Fisher’s linear discriminant function (FDF) is its use in transforming multivariate data into a new univariate variable. This then makes possible a new option for the variance analysis of multivariate data, in addition to the multivariate analysis of variance (MANOVA). The aim of this work was to select groups of seven characteristics of quality in coffee seedlings using six criteria for selection, to use the FDF to transform such groupings of characteristics into a new variable, and then to compare interpretation of the results obtained from the univariate and multivariate analyses of variance of the characteristics and this new variable, with a view to its use in evaluating coffee seedlings. A randomised block design was used to assess the effect of organic fertiliser on the formation of seedlings in coffee cv. Catuaí Vermelho IAC- 44, evaluating the following characteristics: seedling height, diameter, root length, dry weight of shoots and roots, leaf area, number of leaves and total dry weight. According to the selection criteria used, different subsets of the selected characteristics are possible. The use of the FDF is shown to be viable in discriminating between treatments. Univariate analysis of the new variable obtained with the FDF and multivariate analysis (MANOVA) was able to detect differences between the treatments, however, it is simpler to apply FDF methodology.