Coverage mobilization in the sowing line and its influence on temperature and water content and on maize emergence

Evandro M Brandelero,Ricardo Ralisch,Augusto G De Araújo

doi:10.1590/1809-4430-eng.agric.v35n1p98-108/2015

Evandro M Brandelero, Ricardo Ralisch + Show 1 more

Open Access

https://doi.org/10.1590/1809-4430-eng.agric.v35n1p98-108/2015

Copy DOI

Abstract

Straw on sowing line modifies seed germination environment regarding temperature and water content. Given these considerations, the aim of this study was to evaluate different mechanisms for coverage mobilization on the sowing line and their effect on germination environment of maize seeds, mainly in relation to the dynamics of straw in the seedbed, water content and soil temperature. Treatments consisted on the combination of two mechanisms at front of furrow opener, composed of cutting disc and row cleaners, with three mechanisms behind the seed furrower for returning the soil, consisting of three covering mechanisms, commercial and prototype models. It was found that straw presence on the surface of sowing line contributed to germination of maize seeds, maintenance of temperature and soil water content. The cutting disc treatment, associated with prototype, introduced percentages of water content near the ones in bottom layer, and this soil water content was 29.7% with 93.75% of straw coverage and deeper seeding depth, granting better conditions for seed germination. However, the straw coverage removal on soil by the row cleaners and its low sowing depth caused water loss in the lines resulting in great reduction of the emergence speed index in maize seedlings.

Highlights

Straw on soil surface is a technical recommendation to reduce erosive processes by rainwater and wind, assisting in the sustainability of agricultural cultivation (VEIGA et al, 2010)
Straw mobilization in No-tillage system (NTS) requires seeders with adapted furrowers for the cutting (CEPIK et al, 2010) or side dislocation, as well as for its return on sowing line (BRANDELERO et al, 2012a) which can contribute for the finishing quality of sowing
The study of the relationship soil- machine-plant contributes to a great initial establishment of plants (ROSA, 2009), as the intensification of machine traffic acts on the increase of soil compaction and reduction of root growth (ROSA et al, 2008)

Summary

Introduction

Straw on soil surface is a technical recommendation to reduce erosive processes by rainwater and wind, assisting in the sustainability of agricultural cultivation (VEIGA et al, 2010). No-tillage is carried out with seeders- fertilizers that prepare the soil on sowing line, using furrower mechanisms for straw mobilization and deposition of fertilizers and seeds on soil (ARATANI et al, 2006), as well as landing mechanisms to improve coverage and contact soil-seed (BRANDELERO et al, 2012b). These furrowers provide an effect on sowing line, modifying soil physical environment concerning mobilized area and sowing dept (FALLAHI & RAOUFAT, 2008). It is most frequently employed the plane cutting discs at the front of a shank type furrower (SANTOS et al, 2008)

Objectives

Methods

Results

Conclusion