Realizing No-till System in the subtropical regions of Brazil

#SDGAction42889

Description

Intro

In subtropical regions of Brazil, the main grain production model is soybean/winter cereal under No-till, fulfilling two precepts of conservation agriculture: soil minimum tillage and crop residues in soil surface. These precepts are insufficient to promote sustainability. The high decomposition rate of crop residues makes ephemeral both soil aggregate stability and soil cover. Thus, in subtropical regions, No-till needs to be understood as a management system (No-till System), with adoption of others conservationist precepts: crop diversification; addition of biomass to the soil to attend the biological demand of the soil; harvesting/sowing process; agriculture terraces; and sowing in contour.

Objective of the practice

Training researchers, teachers and students of agricultural sciences, as well as technical assistants, extension agents and farmers to convert ‘No-till’ to ‘No-tillage System’. Converting the ‘No-till’ practice into ‘No-till System’ crop diversification is essential in the adopted production models, including summer grasses cultivation (maize, sorghum, millet, Urochloa…) at least once every three years. Summer grasses have potential to produce crop residues (straw and, most import, root) in quantity (at least 12 t/ha/year), quality (high C/N), and frequency to meet the biological demands of the soil in subtropical regions. Thus, planning production models with the required crop diversification is the essential factor to be observed when converting ‘No-till’ into ‘No-till System’, so that high technical and economic benefits would be generated. Minimizing the time interval between harvesting and sowing the subsequent crop (harvesting/seeding process) facilitates the crop diversification in different production systems, promotes greater number of harvest per year, increases the organic material input to the soil, promotes stability of soil aggregates, and maintains permanent soil cover. Agricultural terraces and sowing in contour are essential to retain the rainwater where it falls, avoiding losses of water, soil, organic matter, and fertilizers, as well contamination of the surrounding systems.

Partners

Partnerships - Brazilian Agricultural Research Corporation; Passo Fundo University; National Cooperativism Learning Service (SESCOOP); Governments of the States of Rio Grande do Sul, Santa Catarina e Paraná; Rio Grande do Sul State Program for Management and Conservation of Soil and Water; Agronomy Society of the State of Rio Grande do Sul; Riograndense Association of Technical Assistance and Rural Extension Projects (EMATER/RS); Agricultural Research and Rural Extension Company of the State of Santa Catarina (EPAGRI); Institute of Technical Assistance and Rural Extension of the State of Paraná (EMATER/PR); and Syngenta-Brazil.

Implementation of the Project/Activity

conducting training events focused on ‘Agronomic Update in Conservation Agriculture’, aiming researchers, teachers, and students of agricultural sciences and, most important, at technical assistants, extension agents, and farmers; presenting lectures on Conservation Agriculture; promoting Field Days; implementing Technological Reference Units and Demonstration Units; and participating in Exhibition-Agricultural Trade Shows, demonstrating features of ‘No-Till’ x ‘No-Till System’.

Results/Outputs/Impacts

Activities developed from March 2015 to February 2019: 31 trainings, involving 784 class hours and 780 attendants; 428 lectures, involving 783 class hours and 17,920 attendants; 95 Field Days, involving 450 class hours and 24,132 people; two Technological Reference Units, involving 78 class hours and 1,606 people; 16 Demonstration Units, involving 16 people; and 17 Exhibition-Agricultural Trade Shows, involving 184 class hours and 17,540 people. In 2017, the water infiltration rate in the soil was 15 mm/h under ‘No-till´ and 92 mm/h in the ´No-till System´. From 2010 to 2018, soybean cultivation under ‘No-till’ and ‘No-till System’ resulted in average 599 kg/ha more grain yield adopting the ‘No-till System’, ranging from 424 kg/ha in 2016 to 986 kg/ha in 2014. Under drought conditions, observed in the year 2014, soybean yield cultivated under ‘No-till System’ was 3,420 kg/ha and under ‘No-till’ was only 1,500 kg/ha (44 %).

Enabling factors and constraints

The favourable conditions for the success of the activities were: the State Program for the Management and Conservation of Soil and Water was transformed into Public Policy in the State of Rio Grande do Sul and the National Cooperativism Learning Service (SESCOOP), public institutions of technical assistance and rural extension, the Agronomy Society of the State of Rio Grande do Sul, several regional associations of agronomic engineers in Rio Grande do Sul, Santa Catarina and Paraná, and some agricultural consulting companies defined this program as a reference source for soil and water conservation management in the subtropical regions of Brazil. No constraint condition was found and that needed to be overcome.

Sustainability and replicability

Stabilization of soil structure; Reduction of dispersed clay content in the soil surface layer: Elevation of water infiltration rate in the soil; Minimization of water, soil, organic material and fertilizer losses due to erosion: Minimization of contamination of surrounding crop systems; Reduction of the risk of yield losses due to water deficit; Reduction of production costs; Increase productivity and profitability of crop systems.

Conclusions

The activities carried out promoted, within the global scope of agricultural commodities production chains, the emergence of an environment responsive to the fundamentals of the No-till System, due to the economic, social and environmental benefits it produces.

Other sources of information

https://www.embrapa.br/international

SDGS & Targets

Goal 15

Protect, restore and promote sustainable use of terrestrial ecosystems, sustainably manage forests, combat desertification, and halt and reverse land degradation and halt biodiversity loss