Morfologia, massa seca e teores de nutrientes em milho de pipoca e em girassol sob doses de composto orgânico com Zeólita

Abstract

During the composting process the leaching of K and the volatilization of N can occur, causing the loss of quality of the same. The addition of conditioners such as zeolites can promote the slow retention and release of these nutrients, reducing their losses and, consequently, benefiting the plants. Therefore, the objective of this study was to evaluate the morphology, dry mass and nutrient content in the plant material of popcorn and sunflower corn under doses of organic compound with zeolite. Therefore, two experiments were carried out in a greenhouse using a completely randomized experimental design. Four treatments and five replicates were tested, totaling 20 experimental units. The treatments consisted of organic compounds plus zeolite (20, 40, 60 and 80%) and the control (soil only of the arable layer). The soil mixtures with organic compound enriched with zeolite were incubated for 30 days, then characterized. Each mixture (treatment) was distributed in a pot of 2.74 dm³ for later sowing. A nitrogen fertilization of 20 kg of N.ha-1 was made in the planting of popcorn maize. At 30 days, nitrogen fertilization was performed with 100 kg of N. ha-1. For the sunflower, 20 kg of N.ha-1 and 40 kg of N.ha-1 were fertilized in the plantation with ammonium sulfate as the source. At 60 days after sowing, the morphological variables for the two species were evaluated. For both maize and sunflower, measurements were made of shoot height, corn stalk diameter, sunflower harvest diameter and harvested plant material for determination of dry mass and nutrient contents. The dose of 47.70% of the compound plus zeolite mixed to the soil promoted a greater accumulation of dry mass (13.19 g / pot) in the corn of popcorn. The doses of 35.93 and 35.66% of the compound plus zeolite promoted the highest shoot diameter and shoot height, respectively, for popcorn corn. The levels of N, P and K were higher for popcorn at doses with higher amounts of compound. Ca and Mg contents were higher at 49.56% and 40.50%, respectively, in corn popcorn. For the sunflower, the dose of 46.12% of the compound plus zeolite promoted greater accumulation of dry mass (11.40 g / pot). The doses of 58.3 and 53.89% of the compound plus zeolite promoted the highest collection diameter and shoot height simultaneously in the sunflower. N content was higher at 48.20%. The contents of P and K increased with the amount of compound plus zeolite; Ca and Mg reduced with the highest amount of sunflower.