Duration of the effects of scarification and raised bed associated with vegetation cover on soybean yield on an Alfisol

Abstract

The objective of this work was to determine the duration of the effects of the mechanical interventions scarification and raised bed on soybean (Glycine max) grain yield on an Alfisol, as well as to evaluate, through physical indicators, if the use of cover plants during winter increases the duration of these effects. The experimental design was a complete randomized block with four replicates. Two factors were evaluated. The first consisted of types of soil preparation systems: SC14, scarification in November 2014; SC15, scarification in November 2015; RB14, raised bed built in November 2014; and RB15, raised bed built in November 2015. The second consisted of the type of cover crop used: winter fallow, oat, ryegrass, and wheat. From November 2015 to April 2016, soybean was cultivated under the different soil preparation systems. Soil density, total porosity, macroporosity, microporosity, soil saturated hydraulic conductivity, soil resistance to mechanical penetration, and soybean grain yield were evaluated. There was no effect of cover plants after one crop season on the maintenance of soil physical attributes. Changes in soil density, total porosity, and resistance to mechanical penetration, promoted by scarification, are noticeable up to at least 18 months. The continuance of these modifications reflects in soybean grain yield in the second harvest.

Irrigation Water Management Techniques for Lowland Furrow-Irrigated Soybean in Southern Brazil

“…Although the cutback technique showed an increase in θ above field capacity in the initial and middle sections, only this technique provided adequate supply in the final section of the furrows, as the wetting phase supplied the water up to field capacity. The raised seedbeds were also efficient in draining the water excess, from both irrigation and rainfall, from the field throughout the crop season, corroborating the results of Gollo et al (2020) and Fin et al (2018). In addition to water supply characteristics of the irrigation techniques, the raised seedbeds were essential to ensure the correct growth and development of the soybean crop in lowlands.…”

“…Compared with the results obtained by (3,565 kg ha -1 in the 2014/15 growing season) and Fin et al (2018) (over 4,000 kg ha -1 in the 2015/16 growing season), who also used raised seedbeds in lowlands, however, both seasons without water deficit due to regular rainfall distribution, the grain yield (3,361.3 kg ha -1 ) obtained in this study with non-irrigated soybean indicates the risk of grain yield losses in years with irregular or insufficient rainfall, without an irrigation system. Rocha et al (2017) attribute the highest risk of water stress in lowlands to the low water storage capacity of these soils.…”

Urban Gardens’ Potential to Improve Stormwater Management: A Comparative Analysis among Urban Soils in Sorocaba, São Paulo, Brazil

“…Our results presented higher values of density than those observed in other studies [65][66][67][68][69]. Nevertheless, there are few studies of bulk density in urban areas, since forest or rural soils used for agriculture and pasture are more explored [70][71][72][73][74]. In general, medium-textured Brazilian soils may vary from 1.20 g cm −3 to 1.80 g cm −3 [51], so the means between 1.7 g cm −3 and 1.9 g cm −3 are within the expected.…”

Improving irrigation, crop, and soil management for sustainable soybean production in Southern Brazilian lowlands

“…Little increase in grain yield in flooded rice lately, along with weed resistance to the major herbicides available for rice production (Rao et al, 2007), seems to contribute to yield stabilization of about 7.5 Mg ha -1 (Conab, 2020). Rotating rice with soybean or corn crops can control weed (Fin et al, 2018;Giacomeli et al, 2017); nevertheless, less than 33 % of the lowlands have been rotated with other grain crops (Theisen et al, 2017).…”