Two rice cultivars response to nitrogen fertilization and leaf fungicide treatment

Abstract

After potassium, nitrogen is the nutrient most easily undertaken by rice. Its effects on plant physiology are observed by increasing yield. The objective of this work was to evaluate the response of two rice cultivars (IAC 201 e IAC 202) under four nitrogen rates (0, 50, 100 e 150 kg ha^-1) with and without fungicide treatment. The research was carried out on a clayey soil with sprinkler irrigation at the Experimental Station of Unesp, Selvíria- State of Mato Grosso do Sul, Brazil. The experiment was a randomized block design with four replicates. The nitrogen was applied to top dressing, 40 days after germination. The fungicide was applied 30 and 50 days after cropping. The number of panicle per m² did not change by nitrogen use. The IAC 202 cultivar provided greater number of grains per panicle and higher 100 grains mass, resulting in higher grain yield. The IAC 202 presented 4,512 kg ha^-1 of grains and the IAC 201 cultivar 3,800 kg ha^-1. Adequate rate of N was 90 kg ha^-1, adjusted to quadratic function. The fungicide application did not influence any of the productivity components.