Physical Attributes of Soil and Wheat Productivity as a Function of Covering Plants and Mechanical Chiseling

Abstract

Soil compaction is a main physical problem in many growing areas. The use of ground cover crops for soil decompaction has been a subject of many studies. That has promising results both used alone and in association with mechanical chiseling. The objective of this study was to evaluate the influence of cover crops associated or not with mechanical chiseling, for that, on the physical attributes of the soil, and the wheat grain yield, in an Ultisol from the Central Depression of RS. The experimental design used was randomized blocks with 3 replications in each block, in a 2 x 5 factorial scheme. Where the factor A: soil chiseling - chiseled and non-chiseled, and P fator: cover crops – pigeon pea (Cajanus cajan), Crotalaria juncea (Crotalaria juncea), pearl millet (Pennisetum americanum) and velvet bean (Mucuna aterrima). The chiseling was adjusted to a depth of 0.30m, with 5 rods spaced 0.3m apart. The determinations carried out were: macroporosity, microporosity, total soil porosity, bulk density (BD), penetration resistance (RP), and grain yield. The physical attributes of the soil showed improvements in the second year evaluated, highlighting the treatments with pearl millet and velvet bean that showed higher differences. The maximum RP of the Soil was observed at a depth of 0.25m with 1.64 Mpa. There was a significant difference in the RP of the soil between the treatments of factor A at depths of 0.15 - 0.20 and 0.25m. Mechanical chiseling provided a 15% increase in wheat grain yield compared to non-chiseling treatment, while P factor treatments did not provide any gain.