Definição de recomendações de adubação orgânica e fosfatada para a cultura do pinhão-manso em condições irrigadas.

Abstract

The jatropha (Jatropha curcas L.) is an oilseed that is presented as a new alternative for the supply of oil, yet they are still necessary scientific technical information regarding disability of organic and phosphate fertilizer recommendations. The objective of the research was to evaluate the feasibility of different suggestions of organic and phosphate fertilization on vegetative growth and jatropha plants produce components. In this sense an experimental unit with factorial combination of treatments 4 x 4 will be conducted, and the factors consisting of 4 recommendations of organic fertilizer: without fertilization (0 t ha- 1), recommended dose (4 t ha-1), since and half the recommended dose (6 t ha-1) and twice the recommended dose (8 t ha-1), and 4 phosphate fertilizer recommendations (absence of phosphate fertilizer (0), recommended dose (90 kg ha-1) , one and a half times the recommended dose (135 kg ha-1) and twice the recommended dose (180 kg ha-1). We evaluated the growth at 60, 90, 120, 150, 180 and 210 days after transplanting (DAT) for containers, by measuring the plant-1 height, stem diameter, number of leaves plant-1, leaf area plant-1 and the number of plant-1 total branches and one hundred and eighty DAT seedlings to pots were measured growth variables and yield components, including: plant height, number of branches, stem diameter, leaf area, number of inflorescences, number of fruits, number of clusters, number of fruits per cluster, fruit weight, number of seed per fruit, number of seeds per plant and total weight of seeds per plant were affected by fertilizer recommendations. The recommendation of organic and phosphate fertilizer suggested by soil analysis laboratory (4 t ha-1 of organic matter and 90 kg phosphorus ha- 1) was insufficient to obtain productive plants. The isolated use of organic matter in jatropha crop fertilization promotes positive effects on growth variables and yield components. Applying a fertilizer and a half of the dose recommended by laboratory soil organic matter analysis, corresponding to 6 t ha-1 cattle manure, isolated or associated to 135 kg ha-1 P, it is sufficient to provide nutrient demand as N and P in the first year of cultivation. The phosphorus fertilization associated to organic fertilization significantly influenced plant height, number of branches, the stem diameter, leaf area, seed production per plant and the total mass of seeds of Jatropha plants.