Biometria de Sorgo granífero (Sorghum bicolor (L.) Moench) sob influência de crescimento e adubação.

Abstract

Grain sorghum (Sorghum bicolor (L.) Moench) is the fifth most cultivated cereal worldwide, being cultivated in several tropical and subtropical regions, from 2016 to 2020 sorghum occupies the fourth position in the national production of cereal grains. Soil fertility is the characteristic that most corroborates the agronomic value of the area. It defines the soil's ability to provide nutrients to plants in appropriate amounts and proportions to obtain high yields. Fertilization is the agricultural practice that consists of adding to the soil the amount of nutrients that fills the space between what the plant requires and what the soil can provide, also adding the amount lost. Trichoderma spp. changed the scenario of biological control of plant diseases in Brazil. The first product made available on the market for use in Brazil was in 1987. In several situations, products based on T. asperellum are used to promote growth, and can contribute in several fundamental aspects, such as increasing the efficiency in the use of nitrogen, promoting the plant development, as well as productivity and mitigate the impacts of saline stresses. The objective of this experiment was to evaluate the agronomic characteristics of grain sorghum plant under application of growth promoters, associated with fertilization percentiles. The work was carried out in a greenhouse located at the Universidade Federal Rural da Amazônia-UFRA, municipality of Belém-Pará. The experimental design used was completely randomized, adopting a 5x2 factorial arrangement, distributed in four replications, totaling 40 experimental units. The treatments were elaborated with percentages of the recommended fertilization (0, 25, 50, 75, 100%) and Trichoderma asperellum (Without and With). The variables A30, A45, A60, DC30, DC60, Comp30, Comp45, Comp60, MSPA, MP, were significantly influenced by treatments with fertilization, presenting for most of these variables the maximum peak before the maximum recommended dosage. The Comp30 variable was significantly influenced by the interaction between treatments. In Comp45, the influence of treatments was observed in isolation. The DC45 was the only variable that did not show any influence for the treatments used alone or in interaction. Fertilization positively influenced the agronomic characteristics of grain sorghum, from the vegetative stages to production.