Scientia Agrícola
URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/12094
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Item Growth, development, and fertilizer-15N recovery by the coffee plant(Escola Superior de Agricultura "Luiz de Queiroz", 2007-09) Fenilli, Tatiele Anete Bergamo; Dourado-Neto, Durval; Trivelin, Paulo César Ocheuze; Favarin, José Laercio; Costa, Flávio Murilo Pereira da; Bacchi, Osny Oliveira SantosThe relationship between growth and fertilizer nitrogen recovery by perenial crops such as coffee is poorly understood and improved understanding of such relations is important for the establishment of rational crop management practices. In order to characterize the growth of a typical coffee crop in Brazil and quantify the recovery of 15 N labeled ammonium sulfate, and improve information for fertilizer management practices this study presents results for two consecutive cropping years, fertilized with 280 and 350 kg ha -1 of N, respectively, applied in four splittings, using five replicates. Shoot dry matter accumulation was evaluated every 60 days, separating plants into branches, leaves and fruits. Labeled sub-plots were used to evaluate N-total and 15 N abundance by mass spectrometry. During the first year the aerial part reached a recovery of 71% of the fertilizer N applied up to February, but this value was reduced to 34% at harvest and 19% at the beginning of the next flowering period due to leaf fall and fruit export. For the second year the aerial part absorbed 36% of the fertilizer N up to March, 47% up to harvest and 19% up to the beginning of the next flowering period. The splitting into four applications of the used fertilizer rates was adequate for the requirements of the crop at these growth stages of the coffee crop.Item Comparison between climatological and field water balances for a coffee crop(Escola Superior de Agricultura "Luiz de Queiroz", 2007-05) Bruno, Isabeli Pereira; Silva, Adriana Lúcia da; Reichardt, Klaus; Dourado-Neto, Durval; Bacchi, Osny Oliveira Santos; Volpe, Clóvis AlbertoThe use of climatological water balances in substitution to complete water balances directly measured in the field allows a more practical crop management, since the climatological water balances are based on data monitored as a routine. This study makes a comparison between these methods in terms of estimatives of evapotranspiration, soil water storage, soil available water, runoff losses, and drainage below root zone, during a two year period, taking as an example a coffee crop of the variety Catuaí, three to five years old. Climatological water balances based on the estimation of the evapotranspiration through the methods of Thornthwaite and Penman-Monteith, can reasonably substitute field measured balances, however underestimating the above mentioned variables.