Efeito da aplicação de Herbaspirillum sp. sobre a produtividade de arroz irrigado

Abstract

Alternative forms in nutritional management of plants have been studied in recent years, with the objective of reducing production costs and reducing the environmental impacts caused by the misuse of inputs. Among the materials studied, the use of diazotrophic nitrogen-fixing bacteria stands out. The objective of this work was to evaluate the effect of seed treatment and foliar application of Herbaspirillum sp. in irrigated rice yield with and without N application. The work was conducted in the experimental area of the Federal University of pampa - Itaqui campus. The experimental design was in randomized blocks, with eight treatments and four replications, where each plot totaled 6.9 m².The treatments were: seed treatment with Herbaspirillum sp., Seed treatment with Herbaspirillum sp. plus a foliar application in the dosage of 1L ha-¹, seed treatment with Herbaspirillum sp. plus a foliar application in the dosage of 2L ha-¹, control without seed treatment, combined or not with urea application. Seed treatment was performed according to the manufacturer's indication in the dosage of 1.2 L for each 100 kg of seeds and 250 mL of the protector, Seeding was carried out on November 9, 2017 at the density of 100 kg ha-¹ of seeds. The fertilization was done together with the sowing, at the dose of 310 kg ha-¹ of NPK in the formulation 05-20-20. Cover fertilization was carried out when the crop was in the v3 / v4 and v7 / v8 stages, at a dose of 55 kg ha-¹ of N in the urea form, and the foliar applications of the bacterium occurred when the crop was in stage v3 / v4 together with the first application of urea coverage. The application of Herbaspirillum sp. more urea, both in seed treatment (TS) and TS, plus leaf application of Herbaspirillum sp. at doses of one and two liters per hectare showed an increase in irrigated rice yield and 20 panicle weight. The application of Herbaspirillum sp. in the irrigated rice crop, associated with nitrogen fertilization, increases rice yield, showing potential for use.