Sorghum Densification with Changes in Plant Spacing Arrangement: Productivity and Qualitative Characteristics of Silage Material

The aim of this study was to evaluate the agronomic performance of sorghum grown in different combinations of row spacing and plant density, as well as possible interferences on silage quality. No other study dedicated to identifying the interference of plant spatial arrangement on the cultivation of silage material has been developed in the productive context of the Amazon Biome, making it necessary to understand the behavior of the studied factors. The treatments were arranged in a split-plot scheme: the plots corresponded to three row spacings (0.45 m, 0.60 m, and 0.75 m) and subplots at four densities (105,000, 120,000, 135,000, and 150,000 plants ha-1). The agronomic and productivity characteristics of sorghum and the fermentative and bromatological characteristics of forage and silage were evaluated. The sorghum plants showed an increase in plant height and green and dry mass yield when using higher densities (p < 0.05). For the culm diameter variable, an isolated effect of the factors was observed, with reduced diameter when grown closer to inter-row spacing or using higher plant densities. No effect of the factors was found (p > 0.05) for morphological plant components. In silage, wider spacing promoted higher dry matter content. Regarding crude protein in the silage, higher percentages were obtained at closer spacing and higher plant density. The sorghum growing in dense conditions is indicated, given the positive performance in productivity and bromatological composition.