Rice (Oryza sativa L.) yield evaluation comparing two soil preparation methods

Abstract

Contextualization: Rice (Oryza sativa L.) cultivation, throughout its vegetative process, generates an increase in bulk density and penetration resistance in soil. The most representative component of production costs is management, even so, land preparation and adaptation reach, and exceed, 20% of the costs. Knowledge gap: As it is a high economic yield crop and little technified in the region, the conservation plows implementation that provide economic and environmental benefits to the community is sought. Purpose: With the aim of promoting a more sustainable production and agriculture, it was proposed to evaluate the soil’s physical properties and the rice crop yield, modifying the conventional preparation with plow to the chisel use. Methodology: The experimental area made up of one hectare was divided into experimental plots, T1: One pass with a vibratory chisel, and T2: Two passes with conventional tillage (plow), in which the soil’s physical properties were evaluated (Real Density, Apparent Density, Porosity and Texture) and the phenological follow-up to the crop development (Germination, Maximum Tillering, Maximum Engrossed, Maturity and Harvest). Soil tests were carried out before and after tillage between 15 and 20 cm depth. The statistical analysis was carried out by means of Analysis of Variance (ANOVA) and graphically, and the techno-economic analysis was carried out based on the production and operation costs comparing between the two types of tillage. Results and conclusions: The results showed that after soil preparation the bulk density decreased by 5,0% for T1 and 13,5% for T2; Likewise, these effects led to an increase in porosity of 13,6% and 29,34%, respectively, and production costs to be $1159,9 USD for T1 and 5,37% higher for T2. At the end, it is concluded that, when evaluating the yield at harvest, there were no significant differences in production because of machining, but a statistical difference was observed between the cost of conventional and reduced tillage, the latter being 148,9% cheaper and less aggressive for the soil.