Coffee-tree floral analysis as a mean of nutritional diagnosis

Plant part analysis for evaluating the nutritional state of the crops is a practice commonly used. The analysis of flowers can allow an earlier diagnosis of nutritional deficiencies, excesses or unbalances, which facilitates its correction before the occurrence of irreversible losses in productivity and quality. The objective of this study were to determine the coffee tree (Coffea arabica L.) flower nutrients sufficiency ranges, to compare and correlate concentrations of nutrients observed in flowers and leaves collected 90 days after bloom, and to correlate the concentrations of nutrients in flowers and leaves with fruit yield. Samples of 26 experimental plots were collected. The plots were set up in nine different orchards five to nine years old and with 3000-5000 plants/ha, in the region of Viçosa, Minas Gerais State, Brazil. Eleven experimental plots were selected with mean yield greater than 7.0 kg/plant of coffee berry for the calculation of the nutrients sufficiency ranges. The concentrations of nitrogen (N), potassium (K), boron (B), iron (Fe), and zinc (Zn) were similar in flowers and leaves, whereas those of phosphorus (P), calcium (Ca), magnesium (Mg), sulfur (S), copper (Cu), and manganese (Mn) differed among the parts. There was correlation among the contents of N, Mg, Fe, Mn, Zn, and Cu in flowers and in leaves. For flowers a model of six variables and for leaves a model of eight variables explained 80% of the variation in the mean yield of the coffee tree plants. It is concluded that, flowers permit earlier diagnosis and greater precision in the diagnosis of the nutritional state of the coffee tree.Peer Reviewe

Coffee-tree floral analysis as a means of nutritional diagnosis

ABSTRACT Plant part analysis for evaluating the nutritional state of the crops is a practice commonly used. The analysis of flowers can allow an earlier diagnosis of nutritional deficiencies, excesses or unbalances, which facilitates its correction before the occurrence of irreversible losses in productivity and quality. The objective of this study were to determine the coffee tree (Coffea arabica L.) flower nutrients sufficiency ranges, to compare and correlate concentrations of nutrients observed in flowers and leaves collected 90 days after bloom, and to correlate the concentrations of nutrients in flowers and leaves with fruit yield. Samples of 26 experimental plots were collected. The plots were set up in nine different orchards five to nine years old and with 3000-5000 plants=ha, in the region of Viçosa, Minas Gerais State, Brazil. Eleven experimental plots were selected with mean yield greater than 7.0 kg=plant of coffee berry for the calculation of the nutrients sufficiency ranges. The concentrations of nitrogen (N), potassium (K), boron (B), iron (Fe), and zinc (Zn) were similar in flowers and leaves, whereas those of phosphorus (P), calcium (Ca), magnesium (Mg), sulfur (S), copper (Cu), and manganese (Mn) differed among the parts. There was correlation among the contents of N, Mg, Fe, Mn, Zn, and Cu in flowers and in leaves. For flowers a model of six variables and for leaves a model of eight variables explained 80% of the variation in the mean yield of the coffee tree plants. It is concluded that, flowers permit earlier diagnosis and greater precision in the diagnosis of the nutritional state of the coffee tree

Evaluation of sources, doeses and application sehedules of nitrogen on drip-irrigated tomato.

O objetivo deste trabalho foi estabelecer critérios para a fertilização nitrogenada do tomateiro de crescimento determinado irrigado por gotejamento, nas condições do Cerrado do Brasil Central.201