Azospirillum brasilense no cultivo de arroz irrigado com tratamento de sementes com insumos químicos e biológicos

Abstract

Rice is grown and consumed throughout the world, being a cereal greater economic and social importance in the world. To achieve high productivity of this culture, the availability of essential nutrients is mainly nitrogen (N). The biological fixation by bacteria of the genus Azospirillum proven capable of helping to supply this nutrient. Moreover, microorganisms are used in the treatment of seeds in order to promote plant growth. The objective of this study was to evaluate the use of urea or Azospirillumbrasilense in the production of rice, associated with the seed treatment with chemical and biological products. The study was conducted in the experimental area of the Rio Grande Rice Institute (IRGA 19 ° Nate) in Itaqui - RS. The experimental design was completely randomized with factorial 2 (Urea / Azospirillum) x 4 (seed treatment), with four replications. Seed treatments for IRGA 430 were: (T1) fungicide + insecticide (control); (T2)chemical + formulated liquid base Trichodermaspp.; (T3)chemical + formulated liquid A. brasilense; and (T4) chemical +formulated liquid the basis of Trichoderma spp. + Formulated liquid A. brasilense. We used foliar application of A. brasilense and application of urea in two stages of plant development. At the end of the cycle evaluated the number of panicles per meter, the number of grains per panicle, weight of panicles, and productivity. For the assessed data there was no interaction between the management factors and seed treatments and significant difference between seed treatments, only for the variable number of panicles per meter. So the management with urea or A. brasilense not interfere with productivity variables for rice cultivar IRGA 430. However, there is increase in rice productivity to manage with use of A. brasilense. Seed treatment with Trichoderma spp. presents increase in the number of panicles per meter, compared to the others.