The impact of improved technological components depends to a large extent on the appropriateness of the intervention for the end-user, the efficiency of the technology transfer mechanism and the socio-economical and political conditions of the technology target area. In order to optimize impact the constraints in each of these areas of influence need to be analyzed and opportunities need to be identified to alleviate these constraints. From a different perspective these constraints can be divided into technical, institutional, socio-economical and political limitations. Technical constraints include the appropriateness of the technology intervention. Institutional constraints include the research /extension integration, technology transfer mechanism, seed multiplication capacity, and adoption information feed-back mechanism. The socio-economic constraints include the presence and capacity of commercial seed multiplication and distribution entities and the market situation regard ing possible price premiums or potential demand for additional supplies (as a consequence of the technology adoption). The political constraints may be adverse governmental policy interventions. The results from different adoption studies are used to demonstrate the importance of appropriate technologies, institutional support, transfer mechanism, and market influence. One case study treats the adoption and impact of cassava technologies within the Integrated Cassava Project in Colombia's north coast. The other study concerns the adoption of cassava variety Rayong 3 in Thailand. The last section of the paper identifies and discusses various opportunities that are open to research and extension institutions to alleviate adoption constraints and that subsequently can translate into higher impact.
This study examined efficient farm management in a friendly policy environment and its implications for agricultural production in Nigeria using the cassava industry as a case study. Data were collected from randomly sampled 360 cassava farmers in Benue State. In-depth analysis of data collected was done using the stochastic frontier production function model. The result of the stochastic frontier production model indicated that government policy which favoured increased input use in cassava production in Nigeria resulted to more than proportionate increase in cassava output in Nigeria. The policy packages on cassava resulted to efficient utilization of production resources in cassava production in Nigeria, and hence profit maximization by the farmers. Technical efficiency in cassava production in Nigeria could be increased by 24% through better use of available resources given the current state of technology – via farmer-specific factors, which included access to improved cassava varieties, access to improved cassava processing technology, access to available cassava markets, access to improved extension services and agricultural credits. Moreover, 98% of the variations in input among the farms were due to differences in technical efficiency occasioned by differences in the relative access of cassava farmers to the cassava policy packages.
Cassava brown streak disease (CBSD) has become a major constraint to cassava production in East and Central Africa. The identification of new sources of CBSD resistance is essential to deploy CBSD mitigation strategies, as the disease is progressing westwards to new geographical areas. A stringent infection method based on top cleft–grafting combined with precise virus titer quantitation was utilized to screen 14 cassava cultivars and elite breeding lines. When inoculated with mixed infections of Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV), the scions of elite breeding lines KBH 2006/18 and KBH 2006/26 remained symptom-free during a 16-week period of virus graft inoculation, while susceptible varieties displayed typical CBSD infection symptoms at 4 weeks after grafting. The identified CBSD resistance was stable under the coinoculation of CBSV and UCBSV with cassava geminiviruses. Double-grafting experiments revealed that transmission of CBSV and UCBSV to CBSD-susceptible top scions was delayed when using intermediate scions of elite breeding lines KBH 2006/18 and KBH 2006/26. Nonetheless, comparison of virus systemic movement using scions from KBH2006/18 and a transgenic CBSD resistant 60444 line (60444-Hp9 line) showed that both CBSV and UCBSV move at undetectable levels through the stems. Further, protoplast-based assays of virus titers showed that the replication of CBSV is inhibited in the resistant line KBH2006/18, suggesting that the identified CBSD resistance is at least partially based on inhibition of virus replication. Our molecular characterization of CBSD resistance in cassava offers a robust virus-host system to further investigate the molecular determinants of CBSD resistance. ; European Union ; Peer Review
Government of Nigeria ; Niger Delta Development Commission ; Shell Petroleum Development Company ; Nigerian National Petroleum Corporation ; United States Agency for International Development
This analysis of global and Asian markets looks at protectionism and substitution (decline in starch trade, rise in trade of cassava feedstuffs) and the Asian regional market for cassava feedstuffs. The degree of substitution between cassava and grains has increased measurably during the postwar period. Cassava's future in world markets depends on its ability to compete with grains; so far this has depended on grain pricing policies and tariff structures of importing countries, making cassava trade more vulnerable than the international grain trade. Cassava competes on a cost, not a price basis. If growth in cassava exports is based on small farm production, initial growth would be based on small-scale processing units, which would call for developing a critical production vol. based on domestic markets, in the 1st place. Except for Thailand, production has not been able to meet the rising demand for products. Improved var. and production technology could provide the increased vol. necessary to meet the domestic demand. Then, if surpluses develop resulting in cost reductions, the country could compete in international markets. (CIAT) ; Este analisis de los mercados mundiales y asiaticos contempla las politicas de proteccionismo y sustitucion (reduccion en la comercializacion del almidon y aumento en la comercializacion de los concentrados a base de yuca), en particular, y el mercado regional asiatico para alimentos para animales. El nivel de sustitucion entre la yuca y los granos ha aumentado considerablemente durante el periodo de posguerra. El futuro de la yuca en los mercados mundiales depende de su habilidad para competir con los granos; hasta ahora, esto ha dependido de las politicas de precios de los granos y las estructuras de las tarifas de los paises importadores, haciendo que la comercializacion de la yuca sea mas vulnerable que la comercializacion mundial de granos. La yuca compite con base en el costo y no en el precio. Si el crecimiento en las exportaciones de yuca se basa en la produccion en fincas pequenas, el crecimiento inicial se basaria en unidades de procesamiento en pequena escala, lo que requeriria el desarrollo de un vol. critico de produccion con base en los mercados nacionales, principalmente. A excepcion de Tailandia, la produccion no ha podido satisfacer la creciente demanda de este producto. Mediante el uso de tecnologia de produccion y var. mejoradas se podria proporcionar un mayor vol., necesario para suplir la demanda nacional. Entonces, si se obtienen excedentes con la consiguiente reduccion de costos, el pais podria competir en los mercados internacionales. (CIAT)
Open Access Journal; Published online: 23 Dec 2019 ; Cassava production in Africa is constrained by cassava mosaic disease (CMD) that is caused by the Cassava mosaic virus (CMV). The aim of this study was to evaluate the responses of a range of commonly cultivated West African cassava cultivars to varying inoculum doses of African cassava mosaic virus (ACMV). We grafted 10 cultivars of cassava plants with different inoculum doses of CMV (namely two, four, or six CMD-infected buds) when the experimental plants were 8, 10, or 12 weeks old, using non-inoculated plants as controls. Three cultivars showed disease symptoms when grafted with two buds, and four cultivars showed disease symptoms when grafted with four or six buds. Most cultivars became symptomatic six weeks after inoculation, but one ('TMS92/0326') was symptomatic two weeks after inoculation, and two ('Ntollo' and 'Excel') were symptomatic after four weeks. Root weight tended to be lower in the six-bud than in the two-bud dose, and disease severity varied with plant age at inoculation. These results indicate that the level of CMD resistance in cassava cultivars varies with inoculum dose and timing of infection. This will allow appropriate cultivars to be deployed in each production zone of Africa in accordance with the prevalence of CMD. ; European Union ; Bill & Melinda Gates Foundation ; Peer Review
Harvesting plays a critical role in the cassava production value chain. A review of some existing cassava harvesting options is necessary to facilitate the proper adaption and uptake of improved harvesting methods applicable to farmers from different parts of the globe. In terms of capacity, manual, semi-manual and fully mechanised harvesting options respectively require about 22–51 man-hha-1, 16-45 man-hha-1 and 1–4 man-hha-1. An added advantage with mechanised options is that the field is left ploughed after harvesting with savings on fuel, time and cost. Mechanised harvesters work best on ridged fields with minimal trash or weeds and relatively dry soils (12–16% d.b. moisture content). Earlier attempts at mechanised harvesting have been affected by constraints such as soil characteristics, nature and size of tubers, depth and width of cluster and bond between tubers and the soil, leading to high tuber damage. Though less research attention is given to cassava harvesting mechanisation, that aspect of the global cassava transformation agenda has always been the problem. There is still room for improvement in the provision of appropriate harvesting options for cassava worldwide and a more concerted effort from both the government and private sector is vital.
The role of cassava in Indonesia is becoming more important, whether it is used for food, for industrial processing or for export. The government of Indonesia has established two policies in the agricultural sector, namely: food diversification and increased productivity in the uplands. Food diversification is needed to reduce dependency on rice as the principal food by way of utilizing various other carbohydrate sources, especially cassava. The policy to increase productivity in the uplands, on the other hand, is launched because the acreage of lowland rice fields has been declining over the years with the conversion of some of this land to non-agricultural use, especially on Java. One way of increasing productivity in the up lands is through crop diversification. However, this diversification program should not affect the current productivity of cassava, since cassava has always functioned as a dominant commodity produced in the uplands. For this reason, the intensification of cassava becomes necessary, through, for example, application of intercropping systems that use suitable plant types, varieties as well as appropriate cultural technologies. Efforts to improve cassava cultivars should be made and the methods to introduce them to the farmers should be improved. When cassava is meant to substitute for rice as a source of carbohydrate, a high-quality cultivar, characterized by low HCN in the roots, needs to be developed. On the other hand, when it is meant for industrial use, a high-yielding cultivar with high starch content, needs to be developed. Special cultivars may also need to be developed when cassava is to be grown under intercropping systems. Cassava breeding in Indonesia is presently done jointly by MARIF, CIAT and Brawijaya University in Malang. MARIF has recently released two new high-quality cultivars, named Malang 1 (parents: CM1015-19 x CM849-1) and Malang 2 (parents: CM922-2 x CM507-37). The selection program carried out by Brawijaya University has produced a number of promising cassava clones, labelled UB 1-2 (parents: MCol 22 x CM849-1), UB 15-10 (parents: CM586-1 x CM523-7), UB 477-2 (parents: CM1002-4), UB 881-5 (parents: CM849-1) and UB566-8 (parents: MBra 35). These clones show their greatest potential in the uplands of subhumid regions like East Java. UB 477-2 is a sweet clone, while clones UB 15-10 and UB 566-8 are suitable for growing under intercropping systems. These promising clones will not be released as high-quality cultivars before they undergo multi-location trials in at least 5 provinces, as stipulated by the Minister of Agriculture of the Republic of Indonesia.
Bericht über Projekte zur Verbesserung der Vermarktung und Verarbeitung von Cassava in Ruanda. Darstellung der Projektplanung und der Entwicklung neuer Techniken in Zusammenarbeit mit der Landbevölkerung. (DÜI-wsl)
The report covers varietal improvement for the period 1990-1993. Not much progress was made in the 1990/91 season due to the occurence of a super typhoon that damaged standing field trials. In recent years, however, progress in selection was made in terms of high yield and dry matter content and good plant type. The cassava germplasm bank of PRCRTC has currently a total of 270 accessions, includeing 30 varieties introduced through tissue culture from Thailand. From this germplasm a polycross nursery and hybridization block were established to incorporate desirable genes into the local cultivars. Since 1991 about 3659 new genotypes have been evaluated by PRCRTC. From these evaluations and screenings two varieties of CIAT origin were released by the Philippines Seedboard. These were CM4014-3 (PSB Cv-9) named VC-4 and MCol 1684 (PSB Cv-10) named VC-5. CM4014-3 is a cross of CM728-3 x CM681-2 of the 1984 CIAT introduced population. This variety had an average yield of 32.9 t/ha and is recommended throughout the country. It has a medium HCN and high starch content which is good for processing. MCol 1684 is a CIAT clone introduced in 1979. This is the first variety intended for regional release in Mindanao. It has had an average yield of 44.8 t/ha for the last 10 years. This variety has high HCN and medium starch contents and is good for starch processing. Preliminary and General Yield Trials with cassava materials from CIAT/Colombia and the Thai-CIAT program resulted in the identification of outstanding clones that are high yielding, have high dry matter content and good plant type. In the General Yield Trial, about 40% of the Thai-CIAT materials had yields of 30-40 t/ha after 9 months and about 10% had yields of 50-65 t/ha. In the General Yield Trial about 45% of entries from CIAT/Colombia had yields of 20-30 t/ha after 10 months and about 36% produced 30-40 t/ha. This population has also high dry matter content. Germplasm selection focuses also on starch content and plant type aside from resistance to mites and scale insects. Promotional yield trials with the recommended cassava varieties were conducted in farmer's fields and farmers made their own selection of desired varieties. Gradually the distribution system of recommended cassava varieties have gained momentum. Lakan and Golden Yellow, both Philippines Seed board varieties, are already widely used by farmers in Samar, Leyte and northern Mindanao for human food, starch production and feeds. MCol 1684 is planted in almost 2000 ha in Lanao del Sur, specifically for starch processing. The other recommended varieties, VC-1, VC-2 and VC-3, are already in the fields of some farmer cooperators. With the joint effort of the local government and the private sector it is expected that rapid diffusion of recommended cassava varieties will be attained through the establishment of cassava nurseries and demonstration farms in strategic areas where cassava is an important crop.
Government of Nigeria ; Niger Delta Development Commission ; Shell Petroleum Development Company ; Nigerian National Petroleum Corporation ; United States Agency for International Development
Not Available ; Achieving food and nutritional security in the midst of a relentless increase in population, rising costs of energy, changes in diet preferences, economic development, and climate risks are major global challenges faced by producers, scientists, policy makers, and governments. It is projected that 70% more food needs to be produced by 2050 in a sustainable manner. Sustainable intensification of crop production, from limited resources, aims for a combination of food and nutritional security, ecological sustenance, and economical productivity. Worldwide, although the sole‐cropping practices of large‐scale modern agriculture produce sufficient food currently to feed the population, significant social and environmental impacts have occurred, including a disparity between food actually produced and food that needs to be consumed as an integral part of a healthy diet, a reduction in biodiversity, decreased resilience to biotic and abiotic stresses, and yield instability. Crop diversification within multiplecropping and intercropping systems provides an alternate, sustainable crop production method with the potential to significantly reduce ecological impact and maximize productivity and nutritional security. Cassava is considered to be a "climate‐smart" crop that can yield well in challenging environments. Cassavabased multiple‐cropping systems, which represent a diversification of cropping methods, have been evaluated and practiced by farmers in developing countries in Africa and Asia. They include the best combinations of crops with different morpho‐phenological features that ensure the efficient and judicious use of land, nutrients, and water resources. Such cropping systems offer maximum total factor productivity and ecosystem services, besides food production,in a sustainable manner. In a previous review published in 2004, crop husbandryand agrotechniques for cassava‐based multiple‐cropping systems involving several ephemerals such as legumes (cowpea, peanut, soybean, mungbean, pigeonpea, vegetable legumes, and others), cereals (rice, maize), and vegetables (okra) with cassava; intercropping cassava under plantations (coconut); and relay/sequential cropping involving cassava were reviewed. The present review describes advances made in crop husbandry and agrotechniques for cassavabased multiple‐cropping systems that have subsequently been evaluated. In addition to the short‐season crops mentioned above, sorghum, bottle gourd, and dwarf pigeonpea could be successfully intercropped with cassava. Nevertheless, other crops, such as onion, cluster bean, garlic, tomato, pearl millet, and chili, are yet to be evaluated in an intercropping system. Cassava could be cultivated successfully under coconut, banana, and rubber plantations. As expected, yields of cassava as well as the associate crops were reduced in intercropping systems, sometimes significantly, compared to the sole‐crop yields, primarily due to the reduction in plant population, mutual shading, and competition for nutrients in intercropping. Nevertheless, yield loss in individual components is often compensated by total factor productivity in the intercropping system. Hence, cassava‐based multiple/intercropping systems have been shown to be efficient and productive with significant economic advantage and total factor productivity. Differences occur in the growth duration of the main and associate crops in cassava‐based intercropping systems. However, evaluation of the efficiency and productivity of an intercropping system can be achieved through estimation of area × time equivalent ratio (ATER) rather than land equivalent ratio (LER). Most of the crops and varieties used in cassava‐based multiple‐cropping studies have involved varieties that had been developed for sole cropping. Genotype versus cropping system interaction and differences in combining ability may result in inconsistencies or variation in location and regional varietal performance under different agroecosystems. Therefore, varieties with traits that are beneficial for complex multiple cropping with maximum complementary effect and minimum crop competition may boost productivity in intercropping. The effect of intercropping on pest and disease incidence has been little studied and warrants further investigation. Fertilizers have been applied to cassava and associate crops without assessing the innate nutrient status of the soil, resulting in negative environmental impacts. Varieties with high nutrient use efficiency and soil test–based site‐specific nutrient management may reduce negative environmental impacts. Although the allelopathic effect of leachates from cassava leaves on crops has been reported, further research on the allelopathic interaction between the various components in cassava‐based intercropping systems is needed. ; Not Available
Cassava plays a major role in both household and national food security in Uganda. However, cassava production in Uganda has been threatened by cassava mosaic disease. The government has made concerted efforts to evaluate, multiply and distribute new cassava planting materials in most districts. The new varieties outperformed the local varieties and quickly replaced them. An economic assessment of this programme using the benefit-cost approach revealed that the internal rate of return for this investment was 167%. This high rate of return can be partially explained by lack of data on some costs incurred by other development partners. The success of this investment was due to the joint contribution of complementary organizations. The biggest lesson learned is that it is important to strengthen the linkages between the research programme and other government institutions especially training, marketing, infrastructure development and political institutions. ; Peer Review
