Regulador de crescimento modificando a arquitetura de plantas de soja

Abstract

The use of plant growth regulators can be an important alternative to modify the architecture of soybean plants in order to increase grain yield. The objective was to evaluate the effects of cytokinin application, via foliar, on nutrition, growth, production components and productivity of soybeans. The experiment was installed in the 2020/21 crop, under field conditions, at the Research and Technology Diffusion Center - CPDT 2 - Paraíso das Águas Unit, MS. The experimental design was in randomized blocks, in a 5x2 factorial scheme, with four replications. The treatments consisted of foliar application of five doses of synthetic cytokinin (0.0; 0.30; 0.60; 1.20 and 2.40 g ha-1), corresponding to 0, 25%, 50%, 100% and 200% of the dose of 1.20 g ha-1 of cytokinin in two application times (V6 and R1). At full flowering (R2) diagnostic leaf sampling was performed for leaf chemical analysis and pigment content. The height of plants and insertion of the first pod (AIV), number of nodes (NNO), number of pods per plant (NVP), number of grains per pod (NGV), mass of one hundred grains (MCG) and yield were evaluated. of grain (PROD). Foliar application of cytokinin at doses of (0.60 g ha-1) in the vegetative phase and at a dose of (0.30 g ha-1) in the reproductive phase, favored the characteristics of chlorophyll a (Ca), chlorophyll b (Cb), total chlorophyll (Cx), carotenoids (c) and nitrogen contents. The application of foliar cytokinin at doses of (1.20 and 2.40 g ha-1), during the reproductive stage of soybean (R1), provides a significant increase, the cultivar (ST 797 IPRO), presents MCG of 14.06 grams and productivity of 3,068 Kg ha-1, respectively, when we apply the growth regulator.

Keywords: Glycine max L., bioregulator, cytokinin, chlorophyll, multivariate