Desenvolvimento do milheto forrageiro e sorgo sudão cultivados em solo em função da aplicação de soro de leite

Abstract

Whey is a byproduct of cheese production, and it accounts for 85-95% of the volume of the milk used and retains 55% of the nutrients. Being rich in minerals it can be used in the soil as a source of nutrients for plants and soil microbiota. The objective of this study was to evaluate the chemical characteristics of the soil under cultivation with millet and sudan sorghum , as well as the development and content of macronutrients present in millet and sudan sorghum in response to fertilization of the soil using whey . The experiment was conducted in pots with a capacity of 8 dm3 in a protected environment. The doses were equivalent to 0, 167, 333, 667 and 1000 m3 ha-1 of whey, determined by the amount of K present in the whey. A factorial was established based on two forage species, two different applications: single dose and dual doses (20 days after emergence of the plants) with four replications, totaling 80 experimental units: 40 of the millet and 40 of the sorghum. The plants were harvested after 42 days. The fresh weight, dry weight and height of the plants were determined. The dry mass was ground to prepare extracts for specific analytical determinations of the following nutrients: N, P, Na, K, Ca and Mg. Soil samples were collected from the vases and the available P, Ca, Mg, K, exchangeable. Na organic matter and also CEes and pH in the saturated extract paste were analyzed. There was a decrease in the production of ADM in both cultures with the single dose application starting from the 667 m3 ha-1 dose in both the millet and the sorghum. For the doses equivalent to 667 m3 ha-1, the single application promoted a higher accumulation of fresh weight for both crops. However, with the dual application the effect occurred at a dose equivalent to 333 m3 ha-1. With the increase in doses, there were increases in all of the ions analyzed, as well as CEes and pH. The dual doses contributed the most to both cultures.