Produtividade, morfometria e acúmulo de nutrientes da palma forrageira sob doses de adubação orgânica e densidades de plantio

Abstract

The cactus is an important forage resource for semiarid regions. Two experiments were conducted during the years 2009 to 2011, at the Experimental Station Caruaru belonging to the Agronomic Institute of Pernambuco-IPA. The objective of the first experiment was to evaluate the effect of different doses of organic manure (20, 40 and 80 t / ha of manure / 2 years) and population densities (20, 40, 80 and 160 thousand plants / ha) on morphology, productive, cladode plant and root system of a palmal IPA Clone-20 with two years of regrowth. The second experiment was to monitor the dynamic composition of N, P and K of cactus pear in different densities (40, 80 and 160 thousand plants / ha) and doses of organic manure (20, 40 and 80 t / ha of manure / 2 years), as well as evaluate the dynamics of N, P and K soluble in manure applied by using bags "nylon" at different times (0, 4, 8, 16, 32, 64.128, 256, 512 and 678 days) of incubation in the soil. For the dry matter yield was found with behaviors quadratic curves, linear and exponential positive for doses of 20, 40 and 80 t of manure / ha / two years respectively. We observed higher yields with increased population density and application of 80 tons of manure. The morphological characteristics of the palm were influenced by the levels of organic manure, tending the major measures with the use of 80 tons of manure / ha / two years. The dry weight of the plant and root system cladodes were influenced by population densities, with exponential curves with positive behavior, trending higher weight per area with increasing population density. The release of N, P and K from manure on populations of 20, 40, 80 and 160 thousand plants / ha ceased to 128 days after fertilizer application. Moreover, it was found that the palm accumulated nutrient probably from other sources. The accumulation rate per area of N, P and K in the populations of 20, 40, 80 and 160 thousand plants / ha increased over the days of growth regardless of doses of organic fertilizer used. Farmers, who want to cultivate cactus using cattle manure will fertilize the palmal more often.