Posts Tagged ‘Conservation agriculture’

Penetration resistance: A practical guide for comparing crop management practices

Posted by Carelia Juarez on , in CIMMYT Publications

Penetration resistance: A practical guide for comparing crop management practices. 2013Verhulst, N.;Cox, R.Govaerts, B. Mexico, DF (Mexico)CIMMYT 4 p. 

98382This material was developed under the CGIAR Research Program on Climate  Change, Agriculture and Food Security (CCAFS) and partly funded by ‘Desarrollo sustentable con el productor’, part of ‘Modernización Sustentable  de la Agricultura Tradicional’, supported by SAGARPA.

Soil water content: A practical guide for comparing crop management practices

Posted by Carelia Juarez on , in CIMMYT Publications

Soil water content: A practical guide for comparing crop management practices2013Verhulst, N.Cox, R.;Govaerts, B. Mexico, DF (Mexico)CIMMYT 4 p. 

98381This material was developed under the CGIAR Research Program on Climate  Change, Agriculture and Food Security (CCAFS) and partly funded by ‘Desarrollo sustentable con el productor’, part of ‘Modernización Sustentable  de la Agricultura Tradicional’, supported by SAGARPA.

Improved wheat performance with seed treatments under dry sowing on permanent raised beds

Posted by Carelia Juarez on , in Journal Articles

Published in Field Crops Research, 2014

Mulvaney, M.J.Verhulst, N.Herrera, J.M.Mezzalama, M.Govaerts, B. 

Two strategies for seeding irrigation are used for irrigated wheat. Wet sowing utilizes pre-sowing irrigation to germinate weed seeds and thus control weeds, followed by sowing. Dry sowing plants into dry soil that is irrigated soon afterward, resulting in higher soil moisture during germination and emergence than wet sowing. Field observations have indicated reduced emergence, plant stands and yield in dry compared to wet sowing on a Vertisol in northwestern Mexico. This disadvantage is more acute when dry sowing is conducted in permanent beds with residue retention (conservation agriculture) compared to the conventional system involving tillage with residue incorporation. To identify the causes of reduced plant stand and yield and examine control options, chemical seed treatment effects on durum wheat (Triticum durum Desf.) and bread wheat (Triticum aestivum L.) performance under wet and dry sowing were investigated over three seasons in a permanent bed system. Four seed treatments were applied: Control (no seed treatment); Carboxin + thiram + chlorothalonil (Vit-Dac; fungicides); Difenoconazole + mefenoxam (Dif-Mef; fungicides); and Thiamethoxam + difenoconazole + mefenoxam (TMX-Dif-Mef; insecticide and fungicides). Plant stands, root rot scores, normalized difference vegetative index (NDVI), and grain yield were determined. Under dry sowing, Dif-Mef and TMX-Dif-Mef increased plant stands by 87% and 104%, respectively, compared to Vit-Dac, and by 152% and 172%, respectively, compared to the control. Under dry sowing, TMX-Dif-Mef increased yield by 9.76% and 17.7% compared to Vit-Dac and the control, respectively. Bread and durum wheat were significantly different for both emergence and yield every growing season. Seed treatments effects were not significant under wet sowing. Treatment differences were not linked with root rot incidence later in the season. Several mechanistic hypotheses to explain the results were explored. TMX has been reported to alter genetic expression to enhance response to early season abiotic stresses, but this has not been reported for Dif-Mef. The different physical conditions during stand establishment, i.e. increased moisture and reduced temperature, under dry sowing compared to wet sowing, could have affected microbial populations which induced biological suppression of germination and/or emergence. Although more research is required to explain the underlying mechanism, wheat producers transitioning to a dry sowing system under conservation agriculture with permanent raised beds may avoid yield loss by utilization of a Dif-Mef or TMX-Dif-Mef seed treatment.

Informe Anual del CIMMYT 2012: La investigacion agricola para el desarrollo mejora la seguridad

Posted by Carelia Juarez on , in CIMMYT Publications

Informe Anual del CIMMYT 2012: La investigacion agricola para el desarrollo mejora la seguridad2013.Mexico, DF (Mexico)CIMMYT 28 p. Series: CIMMYT Informe Anual. 

98963El trabajo del CIMMYT y sus numerosos y valiosos colaboradores de los sistemas de producción de  maíz y trigo es más importante que nunca en la historia del centro. La creciente población de nuestro planeta, el cambio en la dieta de las personas, los limitados recursos de que disponemos, la demanda de biocombustibles y una creciente variabilidad climática, son factores que en conjunto ejercen una extraordinaria presión en el sistema alimentario global. Existen pruebas de esto en todo nuestro entorno.

En 2012, por tercera vez en menos de seis años, padecimos los efectos de una crisis mundial ocasionada por el aumento en el precio de los alimentos, un fenómeno que propició que los precios se duplicaran en comparación con los precios de solo dos años antes. En el despertar de la Primavera Árabe, dos de las principales zonas productoras de trigo e importadoras de cereales, el Norte de África y el Oriente Medio, siguen siendo fuertemente afectadas por el alza del precio del trigo. En años recientes el promedio de importaciones de trigo de todo el continente africano ha sido de más de 35 millones de toneladas anuales, cuyo costo para las naciones de ese continente asciende a más de 12 mil millones de dólares americanos y representa un problema para proveer de productos de trigo a los consumidores de bajos recursos.

Does the use of atrazine in maize grown under conservation agriculture adversely affect soybean productivity in maize-soyabean rotation in Zimbabwe?

Posted by Carelia Juarez on , in Journal Articles

Published in Journal of Agricultural Science 6 (7) : 1-9, 2014

Muoni, T.Rusinamhodzi, L.Mabasa, S.Rugare, J.T.Thierfelder, C. 

Weed management challenges in the early years of conservation agriculture (CA) adoption may require the use of herbicides for farmers to realise the immediate benefits of CA practices. The objective of this study was to assess the effects of atrazine on soybean grown after maize in a maize-soybean rotation under conservation agriculture. Atrazine was applied at 1.8 kg ha-1 active ingredient (a.i), as a pre-emergence herbicide in the maize phase of the rotation. The study was conducted in Zimbabwe at Domboshawa Training Centre (DTC), Henderson Research Station (HRS) and University of Zimbabwe farm (UZ farm) over two seasons (2011/2012 and 2012/2013). Manual weeding was utilised to keep the study area weed free and eliminate interference from weeds. Weed density, weed biomass, soybean germination, soybean biomass and grain yield were measured. The lowest germination of soybean was recorded at 57% in 2011/2012 at DTC under atrazine + glyphosate + metolachlor in combination with manual weeding treatment. Previous atrazine treatment to maize showed no significant differences on soybean biomass accumulation and broadleaf weed density at all sites in both seasons. The highest soybean yields recorded were 3707 kg ha-1 at DTC in 2011/12 season in atrazine + glyphosate + metolachlor plus manual weeding treatment. Based on results obtained in this study it can be concluded that soybean can be grown in plots where atrazine was applied as a pre-emergent herbicide during the maize phase.

Conservation agriculture in southern Africa: advances in knowledge

Posted by Carelia Juarez on , in Journal Articles

Published in Renewable Agriculture and Food Systems, 2014

Thierfelder, C.; Rusinamhodzi, L.; Ngwira, A.R.;Mupangwa, W.; Isaiah, N.; Kassie, G.T.; Cairns, J.E.

The increasing demand for food from limited available land, in light of declining soil fertility and future threats of climate variability and change have increased the need for more sustainable crop management systems. Conservation agriculture (CA) is based on the three principles of minimum soil disturbance, surface crop residue retention and crop rotations, and is one of the available options. In Southern Africa, CA has been intensively promoted for more than a decade to combat declining soil fertility and to stabilize crop yields. The objective of this review is to summarize recent advances in knowledge about the benefits of CA and highlight constraints to its widespread adoption within Southern Africa. Research results from Southern Africa showed that CA generally increased water infiltration, reduced soil erosion and run-off, thereby increasing available soil moisture and deeper drainage. Physical, chemical and biological soil parameters were also improved under CA in the medium to long term. CA increased crop productivity and also reduced on-farm labor, especially when direct seeding techniques and herbicides were used. As with other cropping systems, CA has constraints at both the field and farm level. Challenges to adoption in Southern Africa include the retention of sufficient crop residues, crop rotations, weed control, pest and diseases, farmer perception and economic limitations, including poorly developed markets. It was concluded that CA is not a ‘one-size-fits-all’ solution and often needs significant adaptation and flexibility when implementing it across farming systems. However, CA may potentially reduce future soil fertility decline, the effects of seasonal dry-spells and may have a large impact on food security and farmers’ livelihoods if the challenges can be overcome.

Nutrient management and use efficiency in wheat systems of South Asia

Posted by Carelia Juarez on , in Journal Articles

Published in Advances in Agronomy  125 : 171-259, 2014

Jat, M.L.; Bijay-Singh; Gerard, B.

With the advent of Green Revolution era in the mid-1960s, high-yielding wheat (Triticum aestivum L.) varieties and chemical fertilizers were introduced in South Asia. Fertilizer consumption is continuously increasing since then, but the productivity of wheat is relatively stagnant during the last decade. In South Asia, fertilizers have been applied to wheat as blanket recommendations for regions with similar climate and landform. There exists a large variation in nutrient use efficiencies in wheat because of following blanket recommendations for nitrogen, phosphorus, and potassium in fields differing greatly in nutrient-supplying capacity of the soil. Research carried out in South Asia suggests that further improvement in nutrient use efficiency will become possible by balanced use of nitrogen, phosphorus, and potassium fertilizers, and by rational use of organic manures in wheat systems. Long-term fertility experiments also confirm the need of balanced use of nutrients to produce high sustainable yield levels of wheat. In saline alkali soils, wheat needs to be supplied with higher amounts of nutrients, particularly N, than in normal soils. Band placement of fertilizers, particularly phosphorus, leads to improved fertilizer use efficiency, but appropriate machinery is lacking. Recently introduced site-specific nutrient management strategies for wheat take into account field-to-field variability and can help increase fertilizer use efficiency more than that achieved by following blanket fertilizer recommendations. Conservation agricultural practices consisting of reduced tillage and residue retention in wheat fields have already been introduced in South Asia. Nutrient management strategies for these wheat-growing environments are also being actively worked out. Yield gap analysis shows that productivity of wheat as well as nutrient use efficiencies can be further improved.

Adoption potential of Conservation Agriculture practices in Sub-Saharan Africa: Results from five case studies

Posted by Carelia Juarez on , in Journal Articles

Published in Environmental Management, 2013

Ndah, H.T.; Schuler, J.; Uthes, S.; Zander, P.; Traore, K.; Gama, M.-S.; Nyagumbo, I.; Triomphe, B.; Sieber, S.; Corbeels, M.

Despite the reported benefits of conservation agriculture (CA), its wider up-scaling in Sub-Saharan Africa (SSA) has remained fairly limited. This paper shows how a newly developed qualitative expert assessment approach for CA adoption (QAToCA) was applied to determine its adoption potential in SSA. CA adoption potential is not a predictor of observed adoption rates. Instead, our aim was to systematically check relevant factors that may be influencing its adoption. QAToCA delivers an assessment of how suitable conditions “and thus the likelihood for CA adoption” are. Results show that the high CA adoption potentials exhibited by the Malawi and Zambia case relate mostly to positive institutional factors. On the other hand, the low adoption potential of the Zimbabwe case, in spite of observed higher estimates, is attributed mainly to unstable and less secured market conditions for CA. In the case of Southern Burkina Faso, the potential for CA adoption is determined to be high, and this assessment deviates from lower observed figures. This is attributed mainly to strong competition of CA and livestock for residues in this region. Lastly, the high adoption potential found in Northern Burkina Faso is explained mainly by the fact that farmers here have no alternative other than to adopt the locally adapted CA system—Zaï farming. Results of this assessment should help promoters of CA in the given regions to reflect on their activities and to eventually adjust or redesign them based on a more explicit understanding of where problems and opportunities are found.

Determination of resistance against to Cereal cyst nematode, Heterodera avenae (Wollenweber, 1924) in some wheat germplasm

Posted by Carelia Juarez on , in Journal Articles

Published in Turkiye Entomoloji Dergisi – Turkish Journal Of Entomology 37 (2) : 229-238, 2013

Imren, M.; Toktay, H.; Bozbuga, R.; Dababat, A.A.; Ozkan, H.; Elekcioglu, I.H.

The cereal cyst nematode, Heterodera avenae is one of the most important pests of wheat in many countries in the world with different climatic types. Heterodera. avenae is commonly distributed in the Eastern Mediterranean region of Turkey and all populations investigated belong to the Ha1 group, Ha21 pathotype. This study was aimed to found resistance sources from the national wheat varieties, wheat wild genotypes and international wheat genotypes against H. avenae Karlık?Adana population (Ha21 pathotype). Results showed that four national wheat varieties, seventeen wheat wild genotypes and twenty three international wheat genotypes were found to be moderately resistant against to Eastern Mediterranean Region of Turkey H. avenae population. Among these genotypes, the national bread wheat variety, Adana 99 (PFAU/SERI82//BOG”S”), some wild genotypes and international genotypes can be used in national wheat breeding programmes. However, Cre1 was not showed completely resistant against H. avenae. Additionally resistance sources in of Turkish national wheat and wild genotypes needs to be determined.

Understanding the impact and adoption of conservation agriculture in Africa: A multi-scale analysis

Posted by Carelia Juarez on , in Journal Articles

Published in  Agriculture, Ecosystems and  Environment, 2013

Corbeels, M.; Graaff, Jan de; Ndah, T.H.; Penot, E.; Baudron, F.; Naudin, K.; Andrieu, N.; Chirat, G.; Schuler, J.; Nyagumbo, I.; Rusinamhodzi, L.;Traore, K.; Mzoba, H.D.; Adolwa, I.S.

Conservation agriculture (CA) is increasingly promoted in Africa as an alternative for coping with the need to increase food production on the basis of more sustainable farming practices. Success with adopting CA on farms in Africa has been limited, despite more than two decades of research and development investments. Through analyzing past and on-going CA experiences in a set of case studies, this paper seeks to better understand the reasons for the limited adoption of CA and to assess where, when and for whom CA works best. CA is analyzed and understood within a framework that distinguishes the following scales of analysis: field, farm, village and region. CA has a potential to increase crop yields in the fields, especially under conditions of erratic rainfall and over the long-term as a result of a gradual increase of overall soil quality. The impact on farm income with the practice of CA on some fields of the farm is far less evident, and depends on the type of farm. The lack of an immediate increase in farm income with CA explains in many cases the non-adoption of CA. Smallholders have often short-term time horizons: future benefits do not adequately outweigh their immediate needs. Another key factor that explains the limited CA adoption in mixed crop-livestock farming systems is the fact that crop harvest residues are preferably used as fodder for livestock, preventing their use as soil cover. Finally, in most case studies good markets for purchase of inputs and sale of produce – a key prerequisite condition for adoption of new technologies – were lacking. The case studies show clear evidence for the need to target end users (not all farmers are potential end user of CA) and adapt CA systems to the local circumstances of the farmers, considering in particular the farmer’s investment capacity in the practice of CA and the compatibility of CA with his/her production objectives and existing farming activities. The identification of situations where, when and for whom CA works will help future development agents to better target their investments with CA.