Utilização de águas marginais e fósforo no cultivo do pinhão-manso.

Abstract

The cultivation of physic nut in recent years has received special attention, being considered a altemative energy source universally accepted. The objective of this work to analyze the feasibility of using lower quality water for irrigation and phosphorus leveis on yields of physic nut during the 3rd and 4th year of production. Growth variables were influenced by the blades of fluid consumption of the physic nut from 30 days after pruning. The number of leaves and stem diameter were influenced by phosphorus at 30 and 90 days after pruning, respectively. Variables, plant height and leaf area were affected by the interaction of 30 and 30, 60 and 90 days after pruning, respectively. The weight of the fruit and water use effíciency were influenced by the depth of fluid consumption of the physic nut, however, were not affected by phosphorus. The stem diameter, number of leaves and water consumption are linear and negatively affected by salinity of irrigation water. Leaf area was the only variable influenced by the growth rates of phosphorus in the three evaluations and the number of leaves was affected at 30 DAP. The salinity of irrigation water from 1.6 dS m"1 negatively interferes with the accumulation of dry leaves of physic nut. The average water consumption of the physic nut decreased 22.5% per unit increase in salinity of irrigation water for 180 days. The physic nut demonstrates sensitivity to salinity of irrigation water with electrical conductivity higher than 1.6 dS m"'. The increase in hydration with wastewater resulted increase in leaf gas exchange, notably in the rate of carbon assimilation. The content of the elements the following order of decreasing leaf: N> K> Mg> Ca> P> Na> S> Fe> Mn> Zn> Cl> Cu. With increasing hydration leveis of P, Zn, and Cu increased while the leveis of Cl, Mn and Na decreased their concentrations in the leaves. P2O5 doses applied did not influence the content of any of the elements studied. The salinity of irrigation water led to reductions in stomatal conductance, leading to declines in rates of transpiration and photosynthesis, and increased leaf temperature. The nutrient content of the leaves the following order: K> N> Ca> Mg> P> S and Cl> Na> Fe> Mn> Zn> Cu, for macro and micronutrients, respectively. Aside from covering ali aspects evaluated increased with increasing salinity of irrigation water. The maximum N and K in leaves of physic nut was obtained with an ECw of 2.2 dS m"1. The irrigation leveis influenced the yield components such as issuance of inflorescence, number of bunches, fruit number and weight of 100 seeds. The oil content was significantly influenced by the levei of fluid there was an increase of 11.51% at 1.25 levei of fluid. The increase of phosphorus leveis influence among the variables studied, only the number of clusters. The number of days to issue the inflorescence, number of clusters per plant, grain yield and oil content of seeds of physic nut were negatively affected by increasing salinity of irrigation water. Acculturate of physic nut irrigated with electrical conductivity of 1.3 dS m"1 reaches an average 10% loss of mass and therefore the oil content in seeds. Only the number of days to inflorescence emission was affected by phosphorus. There was a positive correlation between 100 seed weight and oil content of seeds of physic nut. Physic nut plants irrigated with 100% of field capacity with wastewater show a reduction in mass production and leaf area compared with plants irrigated with water supply. This species has the ability to adjust osmotic from the synthesis of glycine betaine. However, demonstrates that the accumulation of proline in the tissue is not effective for osmotic adjustment due to its low leveis accumulated in the tissue. The application of layers of fluid replacement with domestic wastewater in the soil caused an increase in pH with increasing water availability, however, the effect on potassium was reversed. With respect to the P2O5 leveis in the soil profile, there was no efTect on the elements in the study.