Evolution of crop yields in different tillage and cropping systems over two decades in southern Brazil

Abstract

In the last three decades, the no-tillage system (NT) has provided environmental and economic advantages for farming in southern Brazil, especially when associated with crop rotation. The objective of this study was to evaluate the effects of different tillage and cropping systems on the grain yields of soybean, maize and wheat, in a 23-year experiment established on an Oxisol in the southern region of Brazil. The experiment was carried out in randomized block experimental design with four replications. The treatments consisted of three tillage systems [NT, NT with chiseling every three years (NTC), and conventional tillage (CT)] and two cropping systems [an annual crop sequence with wheat in the winter and soybean in the summer, designated as crop succession (CS), and a 4-year crop rotation with the following species in winter-summer, respectively: white lupine-maize; black oat-soybean; wheat-soybean; and wheat-soybean (CR)]. Soybean yields were correlated to the water requirement satisfaction index (WRSI) estimated for the soybean reproductive period. With few exceptions, the NT showed higher soybean yields in relation to CT from the 7th year of the experiment onwards, especially under crop rotation and in growing seasons with lower water availability expressed by lower WRSI values. The percentage of NT soybean yield advantage over CT increased consistently over the time, and this increase was greater in CR than in CS, reaching on average 23%. The yields of wheat and maize were not influenced by the tillage systems, but the wheat yields were increased by crop rotation. In the most of the growing seasons, the soil chiseling, at every three years, did not increase significantly the yields of soybean, maize and wheat. Crop rotation and NT, allowed high and stable crop yields, especially under water-stress conditions. Results indicate the need of minimizing soil disturbance and diversifying cropping system for sustainable grain production in southern Brazil.

Intercropping of soybean cultivars with Urochloa

“…These findings may contribute to the optimization of the land use for CLS, and also suggest the potential for a high biomass production, when these fodder grasses are used as cover crops. According to Franchini et al (2012), the use of cropping systems that enable a high amount of biomass production is important for the appropriate management of NTS. In CLS, the availability of pasture in the off-season of summer crops is important for maintaining an adequate supply of forage to cattle (Balbinot Junior et al 2009, Balbino et al 2011.…”

“…The use of NTS increases the stability of crop production, with minimal environmental disturbance (Franchini et al 2012). However, the long-term sustainability of NTS requires the implementation of crop rotations, minimum soil disturbance, and the cultivation of species with high longevity of straw, such as those of the Urochloa genus (Silva et al 2004).…”

Effect of Soil Tillage and Adaptability of Argomulyo and Burangrang Varieties in Madagascar Dry Season with Cold Temperature

“…Higher porosity means higher air capacity but lower soil moisture. Franchini et al (2012) reported higher soybean yields in no tillage from the 7th year of the experiments, especially in planting seasons with lower water availability. No tillage is capable to increase some soil nutrients that can improve these nutrients availability in the soil.…”

Weed Incidence After Soybean Harvest in No-Till and Conventional Tillage Croprotation Systems in Roraima’s Cerrado

“…The no-till system is considered to the most important for the sustainability of Brazilian agro-ecosystems (Crusciol et al, 2010;Franchini et al, 2012;Nascente et al, 2013). Currently, it is estimated that this system in used in 75% of the area occupied by annual grain cultivations in Brazil (Embrapa, 2015).…”