THIERFELDER C.,CIMMYT |
BUNDERSON W.T.,Total LandCare |
JERE Z.D.,Total LandCare |
MUTENJE M.,CIMMYT |
NGWIRA A.,Chitedze Research Station
Experimental Agriculture | Year: 2015
Conservation agriculture (CA) was introduced to farmers in Malawi to address soil degradation, declining crop productivity and the need to adapt to climate variability and change. This research from 2005 to 2014 aimed at analysing the effects of CA on longer-term productivity and profitability compared with conventional systems as practiced in two communities of Central Malawi. CA treatments outyielded conventional ridge tilled control plots in Mwansambo and Zidyana on average by between 22 and 31%, respectively. An economic analysis from 2011 to 2014 found that, on average, income was 50 and 83% greater in CA systems than in conventional systems. The crops were produced with 28 -39 less labour days ha−1 compared with the conventional practice, leading to greater net benefits. Despite the higher returns with CA, there are still challenges with residue retention, weed control, adequate rotations, management of pests and diseases as well as other socio-economic constraints. At the same time, there are opportunities to address these challenges through site-specific and adaptive research using innovation systems approaches. Copyright © Cambridge University Press 2015
Thierfelder C.,CIMMYT |
Chisui J.L.,Total LandCare |
Gama M.,Machinga ADD |
Cheesman S.,CIMMYT |
And 4 more authors.
Field Crops Research | Year: 2013
In Malawi and throughout much of Africa, maize yields have declined over the past several decades due to continuous cultivation, often in monocropping with little or no inputs. As a result, soil degradation has been aggravated by the loss of valuable top soil caused by rainwater runoff due to the absence of effective conservation practices. To combat this trend, Conservation Agriculture (CA) systems were introduced using a pointed stick or hand hoe to plant directly into untilled soil with crop residues as surface mulch. The objective of this study was to compare the effects of different cropping systems (CA and conventional) on soil physical and chemical parameters and long-term maize productivity in target communities of the southern and central regions of Malawi. This study analysed the effects of CA on soil parameters and maize yield over eight cropping seasons. The biophysical variability of the communities was explored through principal component analysis. Results showed that maize yields in CA systems were strongly affected by rainfall infiltration, which was 24-40% greater compared with the conventional ridge and furrow system. In some cases, maize yields in CA plots were double that of conventional tillage plots. The larger water infiltration observed in CA plots relative to conventional tillage indicated that CA systems may increase access to soil water by the crop and offset the negative effects of seasonal dry spells. Yield benefits of CA over conventional tillage systems were greater especially from the 5th season although, in some instances, greater yields on CA were recorded almost immediately. CA can be practiced in diverse environments from sandy to clay soils, nutrient rich to infertile soils and from low to high rainfall areas as long as adequate inputs (fertilizer, herbicides and labour) are available with good extension support to farmers, especially in the initial years. © 2012 Elsevier B.V..
Thierfelder C.,CIMMYT |
Matemba-Mutasa R.,CIMMYT |
Bunderson W.T.,Total LandCare |
Mutenje M.,CIMMYT |
And 2 more authors.
Agriculture, Ecosystems and Environment | Year: 2016
Future threats of climate variability and change and accelerated soil degradation in southern Africa have increased the need for more sustainable and "climate-smart" agriculture practices. Manual systems of conservation agriculture (CA) based on seeding into planting basins or direct seeding techniques have received increased attention over the last decade. However, a critical review of the pros and cons of the different manual seeding systems under different agro-ecologies has been lacking. This paper aims at analysing different manual seeding systems in areas extending from central Mozambique to central Malawi. Results show that CA systems perform differently in contrasting agro-ecological environments. Direct seeded treatments had greater maize yields than conventional tillage practices by an average of 12-27% and outperformed the conventional practice in nine out of fourteen yield comparisons. Basin planted treatments performed well only in Sofala and Manica (15%) with yield penalties of -9% in Tete. The strongest factor influencing maize grain yields in the more variable areas of Manica and Sofala was the quality of season and the location, whereas tillage treatment and location were more important in the higher rainfall areas of Tete. Direct seeding systems out-yielded other treatments in areas of higher rainfall and responded better to a favourable environment than conventional tillage practices. CA systems, especially direct seeding in Malawi, Manica and Sofala, showed greater financial returns to investments and labour productivity due to reduced labour costs and higher yields. Labour savings of up to 43 labour days ha-1 could be achieved with direct seeded treatments in Malawi. The results of this research clearly highlight the need for site-specific recommendations and adaptation of CA systems to different agro-ecological environments. Blanket recommendations of one CA system across many agro-ecologies, as has often been done in the past, will only lead to underperformance of CA in some areas and rejection by smallholder farmers if yield benefits are not achieved. © 2016 Elsevier B.V.