Conservation Agriculture: Gateway for Sustainable Intensification of Smallholder Systems

The Conservation Agriculture (CA) practices with increased acceptance across the globe are being considered as harbinger for sustainable intensification of smallholder production systems. Its positive impact on natural resources, and adaptation to and mitigation of climate change effects are widely acknowledged. In developing world specially Asia and Africa, CA is a relatively new introduction and hence capacity development is vital for development, adaptation and scaling CA based technologies for impact at scale on smallholder farmers in these regions. The training objectives were centered on understanding Conservation Agriculture (CA) and its applications in Asia and Africa. The key findings from the training were that participants need more collaboration with educational institutions and stakeholders when it comes to new knowledge and information, that they would need to re-visit the research, education, and extension linkages vis-à-vis the CA practices, and that the information gained during the course had to cascade to students and the farming community. The participants were pleased that the CA practices was out and that they could begin to explore different areas they could implement on-site in their contexts. Furthermore, participants noted that the CA practices was a useful technology to their work situations. Finally, the participants stated that the partnerships they had with the different experts represented by the different institutions was paramount to the subsequent programs and activities, that would follow the CA practices

Conservation Agriculture and Scale of Appropriate Agricultural Mechanization in Smallholder Systems

This manual has focused on the need to amplify and accelerate adoption of conservation agriculture (CA) practices that enable productivity increases on a sustainable basis. The development of the training manual on ‘Conservation Agriculture and Scale Appropriate Agricultural Mechanization in Smallholder Systems’ is an outcome of the series of advanced training programs on Conservation Agriculture over past one decade. The objectives of this training manual are; (1) To foster capacity building of researchers, extension workers, farmers and machinery manufacturers to promote CA in Asia and Africa; and (2) To raise the awareness of policy planners and decision makers to develop a strategic plan for the development of CA and agricultural mechanization in the developing world. There are several initiatives in South Asia and Africa to promote CA practices as environment-friendly and alternative to conventional agriculture. However, little has been done to document the CA practices or even lessons learnt from these initiatives. Farmers today still lack access to information on CA practices. This is a comprehensive manual that explains in a step by step easy to follow manner on how to implement CA by smallholders in Asia and Africa. It explains what CA is, and why it is important, how to use CA principles in the field and highlights the issues and challenges that researchers, farmers, machinery manufacturers and service providers may encounter when they adopt and adapt CA practices. This manual aims to be a valuable reference and is intended for use by researchers, agricultural extension officers/workers, farmers, machinery manufacturers and service providers to promote CA in Asia and Africa for increasing productivity and reducing poverty. It is written in clear, easy-to-understand language, and is illustrated with numerous figures and tables. It is not intended to cover the subject of conservation agriculture comprehensively but to provide an overview of the principles and practices. Indeed, as the training draws from many distinct disciplines, it is unlikely that any one person will have the necessary technical skills to cover the complete course content. Manual also focuses on two crucial aspects: the provision of farm mechanization services as a viable business opportunity for entrepreneurs, and the essential criteria of raising productivity in an environmentally sensitive and responsible way. This manual is also designed to serve as source of information for custom hire service providers – whether already in the business or intending to start their own hire service business – with skills and competencies in both the technical and the management aspects of the small-scale mechanization business. CA to reach smallholder farmers needed the publication of simplified technical manual. This manual contains useful technical information on CA practices that offer practical answers to questions normally asked by farmers of what, why, how

A Compendium of Key Climate Smart Agriculture Practices in Intensive Cereal Based Systems of South Asia

CSA initially proposed by FAO in 2010 at “The Hague Conference on Agriculture, Food Security and Climate Change (CC)”, to address the need for a strategy to manage agriculture and food systems, under climate change. The CSA by its original proponents describes the three objectives; i) sustainably increasing agricultural productivity to support equitable increases in incomes, food security and development; ii) adapting and building resilience to climate change from the farm to national levels; and iii) developing opportunities to reduce GHG emissions from agriculture compared with past trends. Since then, these three objectives (in short food security, adaptation and mitigation) are designated as the three “pillars” (or criteria) of CSA within the agricultural science and development communities. Climate Smart (Sustainable Management of Agricultural Resources and Techniques) Agriculture is an approach of crop production, which deals with the management of available agricultural resources with latest management practices and farm machinery, under a particular set of edaphic and environmental conditions. It works to enhance the achievement of national food security and Sustainable Development Goals (SDGs). CSA is location specific and tailored to fit the agro-ecological and socio-economic conditions of a location. CSA may be defined as “agriculture that sustainably increases productivity, resilience (adaptation), reduces/removes greenhouse gases (mitigation), and enhances achievement of national food security and development goals.” Therefore, if CSA implemented at right time with required resources, techniques and knowledge in a particular typological domain, will lead towards food security while improving adaptive capacity and mitigating potential for sustainable agriculture production

Harnessing genetic potential of wheat germplasm banks through impact-oriented-prebreeding for future food and nutritional security

The value of exotic wheat genetic resources for accelerating grain yield gains is largely unproven and unrealized. We used next-generation sequencing, together with multi-environment phenotyping, to study the contribution of exotic genomes to 984 three-way-cross-derived (exotic/elite1//elite2) pre-breeding lines (PBLs). Genomic characterization of these lines with haplotype map-based and SNP marker approaches revealed exotic specific imprints of 16.1 to 25.1%, which compares to theoretical expectation of 25%. A rare and favorable haplotype (GT) with 0.4% frequency in gene bank identified on chromosome 6D minimized grain yield (GY) loss under heat stress without GY penalty under irrigated conditions. More specifically, the ‘T’ allele of the haplotype GT originated in Aegilops tauschii and was absent in all elite lines used in study. In silico analysis of the SNP showed hits with a candidate gene coding for isoflavone reductase IRL-like protein in Ae. tauschii. Rare haplotypes were also identified on chromosomes 1A, 6A and 2B effective against abiotic/biotic stresses. Results demonstrate positive contributions of exotic germplasm to PBLs derived from crosses of exotics with CIMMYT’s best elite lines. This is a major impact-oriented pre-breeding effort at CIMMYT, resulting in large-scale development of PBLs for deployment in breeding programs addressing food security under climate change scenarios

Changing agricultural stubble burning practices in the Indo-Gangetic plains: is the Happy Seeder a profitable alternative?

Every year after the rice harvest, some 2.5 million farmers in northwest India burn the remaining stubble to prepare their fields for the subsequent wheat crop. Crop residue burning causes massive air pollution affecting millions of people across the Indo-Gangetic Plains. We examine different tillage practices to provide urgently needed empirical evidence on how profitable it is for farmers to adopt no-burn technologies, especially the ‘Happy Seeder’ (HS) which is capable of sowing wheat directly into large amounts of crop residue. Apart from analysing the cost of rice residue management and wheat sowing under conventional-tillage and zero-tillage, we identify factors influencing the adoption of the HS and quantify its impact on wheat yields and –production costs. While we do not find any evidence of a yield penalty, our analysis reveals significant savings in wheat production costs, amounting to 136 USD ha–1. In addition, our analysis shows that the HS saves water and facilitates timely wheat sowing. We conclude that the private benefits of HS use combined with its societal benefits of reducing air pollution and enhancing agricultural sustainability justify particular policy support for its large-scale diffusion, to be supplemented by a stricter enforcement of the ban on residue burning

Precise irrigation water and nitrogen management improve water and nitrogen use efficiencies under conservation agriculture in the maize-wheat systems

Abstract A 3-year field experiment was setup to address the threat of underground water depletion and sustainability of agrifood systems. Subsurface drip irrigation (SDI) system combined with nitrogen management under conservation agriculture-based (CA) maize-wheat system (MWS) effects on crop yields, irrigation water productivity (WPi), nitrogen use efficiency (NUE) and profitability. Grain yields of maize, wheat, and MWS in the SDI with 100% recommended N were significantly higher by 15.8%, 5.2% and 11.2%, respectively, than conventional furrow/flood irrigation (CT-FI) system. System irrigation water savings (~ 55%) and the mean WPi were higher in maize, wheat, and MWS under the SDI than CT-FI system. There was saving of 25% of fertilizer N in maize and MWS whereas no saving of N was observed in wheat. Net returns from MWS were significantly higher (USD 265) under SDI with 100% N (with no subsidy) than CT-FI system despite with higher cost of production. The net returns were increased by 47% when considering a subsidy of 80% on laying SDI system. Our results showed a great potential of complementing CA with SDI and N management to maximize productivity, NUE, and WPi, which may be economically beneficial and environmentally sound in MWS in Trans-IGP of South Asia

Re-designing irrigated intensive cereal systems through bundling precision agronomic innovations for transitioning towards agricultural sustainability in North-West India

A study was conducted to design productive, profitable, irrigation water¸ nitrogen and energy use efficient intensive cereal systems (rice-wheat; RW and maize-wheat; MW) in North-West India. Bundling of conservation agriculture (CA) with sub-surface drip irrigation termed as CA+ were compared with CA alone and conventional tillage based and flood irrigated RW rotation (farmer’s practice; ScI). In contrast to conventional till RW rotation which consumed 1889 mm ha−1 irrigation water (2-yr mean), CA+ system saved 58.4 and 95.5% irrigation water in RW and MW rotations, respectively. CA+ practices saved 45.8 and 22.7% of irrigation water in rice and maize, respectively compared to CA with flood irrigation. On a system basis, CA+ practices saved 46.7 and 44.7% irrigation water under RW (ScV) and MW (ScVI) systems compared to their respective CA-based systems with flood irrigation (ScIII and ScIV). CA+ in RW system recorded 11.2% higher crop productivity and improved irrigation water productivity by 145% and profitability by 29.2% compared to farmers’ practice. Substitution of rice with maize (MW system; ScVI) recorded 19.7% higher productivity, saved 84.5% of irrigation water and increased net returns by 48.9% compared to farmer’s practice. CA+ RW and MW system improved energy productivity by 75 and 169% and partial factor productivity of N by 44.6 and 49.6%, respectively compared to ScI. The sub-surface drip irrigation system saved the fertilizer N by 20% under CA systems. CA+ in RW and MW systems recorded ~13 and 5% (2-yr mean) higher profitability with 80% subsidy on installing subsurface drip irrigation system and similar profitability without subsidy scenario compared with their respective flood irrigated CA-based systems

Water budgeting in conservation agriculture-based sub-surface drip irrigation in tropical maize using HYDRUS-2D in South Asia

In water scarce regions of South Asia, diversification of rice with maize is being advocated towards sustainability of cereal-based cropping systems. Adoption of innovative agronomic management practices, i.e., conservation agriculture (CA) and sub-surface drip irrigation (SSDI) are considered as key strategies for much needed interventions to address the challenges of water scarcity under projected climate change. Benefits from CA and SSDI concerning water economy are well-established, however, information about their complementarity and water budgeting in cereal-based systems are lacking. A field study was conducted with process-based model (HYDRUS-2D) to understand water transport, root water uptake and components of soil water balance in maize grown in rotation with wheat after five years of continuous adoption of conservation agriculture. In this study, altogether eight treatments comprising of 6 CA+ treatments (CA coupled with SSDI); permanent beds using sub-surface drip (PB-SSD) with (WR) and without (WOR) crop residue at different N rates, 0, 120 and 150 kg N ha−1 were compared with CA (PB using furrow irrigation-FI with crop residue-120 kg N ha−1) and conventional tillage practices (CT) (CT using FI without crop residue-120 kg N ha−1). Results showed that the model could simulate the daily changes in profile soil water content with reasonable accuracy in all the treatments. Simulated soil water balance indicated higher cumulative root water uptake (CRWU), lower cumulative evaporation (CE) and higher soil water retention in CA+ (PB-SSD+ crop residue at 150 and 120 kg N ha−1) than CA and CT plots. Hydrus-2D model efficiency > 0, RMSE between 0.009–0.026 and R2 value between 0.80–0.92 at P < 0.01 indicates that the model is performing efficiently. The mean evaporation from CA+ treatments was 10 and 36% less than CA and CT treatments, respectively. On average, CRWU under CA+ treatments were 14–48% higher than FI treatments. The mean cumulative deep drainage in CA+ plots was 80–100 mm less than CA and CT plots. In CA+ based plots significantly higher biomass production and radiation use efficiency were observed with reduced water use than CA and CT. Therefore, the study justifies the water-saving nature of CA+, while maintaining higher productivity and meeting the transpiration demand of crops and halting unnecessary evaporation and deep drainage losses