WorldWideScience

Sample records for cassava

  1. Cassava Commercialization in Mozambique

    OpenAIRE

    Donovan, Cynthia; Haggblade, Steven; Salegua, Venancio Alexandre; Cuambe, Constantino; Mudema, Joao; Tomo, Alda

    2011-01-01

    Cassava supplies roughly 30% of all calories consumed in Mozambique, making it the country’s most important food security crop. Over the past several decades, growing urbanization and shifting demand patterns have led to growing opportunities for cassava processing and commercialization. This paper examines the commercial dynamics in Mozambique’s cassava value chain as well as the food security implications of growing cassava commercialization.

  2. Cassava Commercialization in Malawi

    OpenAIRE

    Kambewa, Emma

    2010-01-01

    Malawi continues to rely on maize for household food security. Policies to enhance food security continue to target maize production. Traditionally production and use of cassava was localized in lakeshore areas until the past two decades when maize production was increasingly affected by rainfall variability. Cassava as an alternate food crop has rapidly gained popularity and commercialization of the cassava sector is steadily taking off. Policy and institutional support to diversify the food...

  3. Cassava as a food.

    Science.gov (United States)

    Okezie, B O; Kosikowski, F V

    1982-01-01

    This review has attempted to examine information pertaining to the role of cassava (Manihot esculenta) as a major food source for a large part of the world population, particularly the countries of South America, Africa, and Asia, where it is primarily a major source of energy for 300 to 500 million people. Its cultivation, usually on small farms with little technology, is estimated to cover on an annual basis about 11 million hectares providing about 105 million tons, more than half of which is consumed by humans. The importance of cassava as an energy source can be seen by its growing demand in the European economic community countries where it forms up to 60% of the balanced diets for swine. Cassava is one of the crops that converts the greatest amount of solar energy into soluble carbohydrates per unit of area, thus 1 kg of moisture-free cassava meal may yield up to about 3750 kcal which would mean that a yearly production of 15 tons of cassava meal per hectare would yield some 56 million kcal. The major limitations of cassava as food appear to be its poor protein content and quality and the rapid post harvest deterioration of its roots which usually prevents their storage in the fresh state for more than a few days. However, in addition to its use for culinary purposes, cassava finds application in industrial products such as an adhesive for laundry purposes, for manufacturing paper, alcohol, butanol, dextrin, adhesive tape, textile sizing, and glue.

  4. Cassava (Manihot esculenta Crantz).

    Science.gov (United States)

    Bull, Simon E

    2015-01-01

    Genetic transformation of plants is an indispensable technique used for fundamental research and crop improvement. Recent advances in cassava (Manihot esculenta Crantz) transformation have facilitated the effective generation of stably transformed cassava plants with favorable traits. Agrobacterium-mediated transformation of friable, embryogenic callus has evolved to become the most widely used approach and has been adopted by research laboratories in Africa. This procedure utilizes axillary meristem tissue (buds) to produce primary and secondary somatic embryos and subsequently friable, embryogenic callus. Agrobacterium harboring a binary expression cassette is used to transform this tissue, which is regenerated via cotyledons and shoot organogenesis to produce rooted in vitro plantlets. This chapter details each step of the procedure using the model cultivar 60444 and provides supplementary notes to successfully produce transgenic cassava.

  5. Cassava For Space Diet

    Science.gov (United States)

    Katayama, Naomi; Yamashita, Masamichi; Njemanze, Philip; Nweke, Felix; Mitsuhashi, Jun; Hachiya, Natumi; Miyashita, Sachiko; Hotta, Atuko

    Space agriculture is an advanced life support enginnering concept based on biological and ecological system ot drive the materials recycle loop and create pleasant life environment on distant planetary bodies. Choice of space diet is one of primary decision required ot be made at designing space agriculture. We propose cassava, Manihot esculenta and, for one major composition of space food materials, and evaluate its value and feasibility of farming and processing it for space diet. Criteria to select space crop species could be stated as follows. 1) Fill th enutritional requirements. There is no perfect food material to meet this requirements without making a combination with others. A set of food materials which are adopted inthe space recipe shall fit to the nutritional requirement. 2) Space food is not just for maintaining physiological activities of human, but an element of human culture. We shall consider joy of dining in space life. In this context, space foos or recipe should be accepted by future astronauts. Food culture is diverse in the world, and has close relatioship to each cultural background. Cassava root tuber is a material to supply mainly energy in the form of carbohydrate, same as cereals and other tuber crops. Cassava leaf is rich in protein high as 5.1 percents about ten times higher content than its tuber. In the food culture in Africa, cassava is a major component. Cassava root tuber in most of its strain contains cyanide, it should be removed during preparation for cooking. However certain strain are less in this cyanogenic compound, and genetically modified cassava can also aboid this problem safely.

  6. Recent growth in African cassava

    OpenAIRE

    Nweke, Felix; Haggblade, Steven; Zulu, Ballard

    2004-01-01

    According to the authors, "Cassava serves as a staple food for 200 million Africans, second only to maize in its calorie contribution. In response to a series of devastating attacks by cassava diseases and pests over the past several decades, the International Institute of Tropical Agriculture (IITA) and several national agricultural research services have launched successful cassava research programs... " This brief describes some of the programs, their impact and the drivers of change. It c...

  7. Resistant starch in cassava products

    OpenAIRE

    Bruna Letícia Buzati Pereira; Magali Leonel

    2014-01-01

    Found in different foods, starch is the most important source of carbohydrates in the diet. Some factors present in starchy foods influence the rate at which the starch is hydrolyzed and absorbed in vivo. Due the importance of cassava products in Brazilian diet, the objective of this study was to analyze total starch, resistant starch, and digestible starch contents in commercial cassava products. Thirty three commercial cassava products from different brands, classifications, and origin were...

  8. Feeding cassava foliage to sheep

    OpenAIRE

    Hue, Khuc Thi

    2012-01-01

    The potential of cassava foliage (Manihot esculenta Crantz) as a protein-rich feed in sheep production in Vietnam was examined by studying cassava foliage yield, hydrogen cyanide (HCN) content, toxicity and performance of lambs fed the foliage as a supplement. Cassava foliage fed ad libitum as a protein supplement to a basal diet of urea-treated rice straw gave similar lamb live weight gain (LWG) as diets supplemented with commercial concentrate or protein-rich foliage of stylosanthes (S...

  9. Sensorial evolution of cassava flour (Manihot esculenta crantz) added to protein concentrate cassava leaves

    OpenAIRE

    Lima, Elaine C S; Feijo, Márcia B S; Freitas, Maria C J; dos Santos, Edna R; Armando U.O. SABAA-SRUR; Moura, Luciana S M

    2012-01-01

    Cassava is regarded as the nutritional base of populations in developing countries, and flour, product made of cassava, is the most consumed in the world. The cassava leaves are very rich in vegetable proteins, but a big amount is lost in processing the crop. The objective of this study was to do a sensory evaluation of cassava flour to which a protein concentrate obtained from cassava leaves (CPML) was added. The CPML was obtained from cassava leaves by isoelectric precipitation and added to...

  10. Cassava as an energy crop

    DEFF Research Database (Denmark)

    Kristensen, Søren Bech Pilgaard; Birch-Thomsen, Torben; Rasmussen, Kjeld;

    2014-01-01

    Cassava based bioethanol production is a promising alternative to conventional fossil fuels and commercial production is already well established in several countries. A production based on small holder production may involve a transformation of the existing production system and it is therefore...... imperative to investigate opportunities and barriers for expansion of cassava production. This paper investigates the potential for an expansion of cassava cultivation for bioethanol production in Southern Mali. It is based on a questionnaire survey with 65 households in 2 villages in Loulouni municipality......, which represent two major agro-ecological environments in the Soudan-zone in Mali. The results reveal that farmers are experienced cassava producers and are interested in an expansion of cassava cultivation for bioethanol production and that suitable areas are available, especially for an expansion...

  11. Cassava biology and physiology.

    Science.gov (United States)

    El-Sharkawy, Mabrouk A

    2004-11-01

    Cassava or manioc (Manihot esculenta Crantz), a perennial shrub of the New World, currently is the sixth world food crop for more than 500 million people in tropical and sub-tropical Africa, Asia and Latin America. It is cultivated mainly by resource-limited small farmers for its starchy roots, which are used as human food either fresh when low in cyanogens or in many processed forms and products, mostly starch, flour, and for animal feed. Because of its inherent tolerance to stressful environments, where other food crops would fail, it is often considered a food-security source against famine, requiring minimal care. Under optimal environmental conditions, it compares favorably in production of energy with most other major staple food crops due to its high yield potential. Recent research at the Centro Internacional de Agricultura Tropical (CIAT) in Colombia has demonstrated the ability of cassava to assimilate carbon at very high rates under high levels of humidity, temperature and solar radiation,which correlates with productivity across all environments whether dry or humid. When grown on very poor soils under prolonged drought for more than 6 months, the crop reduce both its leaf canopy and transpiration water loss, but its attached leaves remain photosynthetically active, though at greatly reduced rates. The main physiological mechanism underlying such a remarkable tolerance to drought was rapid stomatal closure under both atmospheric and edaphic water stress, protecting the leaf against dehydration while the plant depletes available soil water slowly during long dry periods. This drought tolerance mechanism leads to high crop water use efficiency values. Although the cassava fine root system is sparse, compared to other crops, it can penetrate below 2 m soil,thus enabling the crop to exploit deep water if available. Leaves of cassava and wild Manihot possess elevated activities of the C4 enzyme PEP carboxylase but lack the leaf Kranz anatomy typical of C4

  12. Cassava biology and physiology.

    Science.gov (United States)

    El-Sharkawy, Mabrouk A

    2004-11-01

    Cassava or manioc (Manihot esculenta Crantz), a perennial shrub of the New World, currently is the sixth world food crop for more than 500 million people in tropical and sub-tropical Africa, Asia and Latin America. It is cultivated mainly by resource-limited small farmers for its starchy roots, which are used as human food either fresh when low in cyanogens or in many processed forms and products, mostly starch, flour, and for animal feed. Because of its inherent tolerance to stressful environments, where other food crops would fail, it is often considered a food-security source against famine, requiring minimal care. Under optimal environmental conditions, it compares favorably in production of energy with most other major staple food crops due to its high yield potential. Recent research at the Centro Internacional de Agricultura Tropical (CIAT) in Colombia has demonstrated the ability of cassava to assimilate carbon at very high rates under high levels of humidity, temperature and solar radiation,which correlates with productivity across all environments whether dry or humid. When grown on very poor soils under prolonged drought for more than 6 months, the crop reduce both its leaf canopy and transpiration water loss, but its attached leaves remain photosynthetically active, though at greatly reduced rates. The main physiological mechanism underlying such a remarkable tolerance to drought was rapid stomatal closure under both atmospheric and edaphic water stress, protecting the leaf against dehydration while the plant depletes available soil water slowly during long dry periods. This drought tolerance mechanism leads to high crop water use efficiency values. Although the cassava fine root system is sparse, compared to other crops, it can penetrate below 2 m soil,thus enabling the crop to exploit deep water if available. Leaves of cassava and wild Manihot possess elevated activities of the C4 enzyme PEP carboxylase but lack the leaf Kranz anatomy typical of C4

  13. An Integrated Investment Appraisal of Cassava Starch Production in Rwanda: The Case of Kinazi Cassava Plant

    OpenAIRE

    Alice Nsenkyire; Glenn P. Jenkins; Mikhail Miklyaev; Octave Semwaga

    2015-01-01

    In April 2012, Kinazi Cassava Plant was established as a government initiative to produce high quality cassava flour, and other value added cassava products. After the successful establishment of the cassava flour plant in Ruhango district, KCP now plans to diversify into cassava starch production to feed the emerging manufacturing industries such as the pharmaceuticals, food processing, breweries, textiles etc. both domestically and for exportation. The study assesses the financial and econo...

  14. Effect of Cassava Flour Characteristics on Properties of Cassava-Wheat-Maize Composite Bread Types

    OpenAIRE

    Maria Eduardo; Ulf Svanberg; Jorge Oliveira; Lilia Ahrné

    2013-01-01

    Replacement of wheat flour by other kinds of flour in bread making is economically important in South East Africa as wheat is mainly an imported commodity. Cassava is widely available in the region, but bread quality is impaired when large amounts of cassava are used in the bread formulation. Effect of differently processed cassavas (sun-dried, roasted and fermented) on composite cassava-wheat-maize bread quality containing cassava levels from 20 to 40% (w/w) was evaluated in combination with...

  15. Phenotypic Approaches to Drought in Cassava: Review

    OpenAIRE

    Emmanuel eOkogbenin; SETTER, TIM L.; Morag eFerguson; Rose eMutegi; Hernan eCeballos; Bunmi eOlasanmi; Martin eFregene

    2013-01-01

    Cassava is an important crop in Africa, Asia, Latin America and the Caribbean. Cassava can be produced adequately in drought conditions making it the ideal food security crop in marginal environments. Although cassava can tolerate drought stress, it can be genetically improved to enhance productivity in such environments. Drought adaptation studies in over three decades in cassava have identified relevant mechanisms which have been explored in conventional breeding. Drought is a quantitativ...

  16. Phenotypic approaches to drought in cassava: review

    OpenAIRE

    Okogbenin, Emmanuel; SETTER, TIM L.; Ferguson, Morag; Mutegi, Rose; Ceballos, Hernan; Olasanmi, Bunmi; Fregene, Martin

    2013-01-01

    Cassava is an important crop in Africa, Asia, Latin America, and the Caribbean. Cassava can be produced adequately in drought conditions making it the ideal food security crop in marginal environments. Although cassava can tolerate drought stress, it can be genetically improved to enhance productivity in such environments. Drought adaptation studies in over three decades in cassava have identified relevant mechanisms which have been explored in conventional breeding. Drought is a quantitative...

  17. Cassava starch in the Brazilian food industry

    OpenAIRE

    Ivo Mottin Demiate; Valesca Kotovicz

    2011-01-01

    Cassava starch is a valued raw material for producing many kinds of modified starches for food applications. Its physicochemical properties, as well as its availability, have made it an interesting and challenging ingredient for the food industry. In the present work, food grade modified cassava starches were purchased from producers and analyzed for selected physicochemical characteristics. Samples of sour cassava starch were included, as well as one sample of native cassava starch. Results ...

  18. Exploiting the Combination of Natural and Genetically Engineered Resistance to Cassava Mosaic and Cassava Brown Streak Viruses Impacting Cassava Production in Africa

    OpenAIRE

    Hervé Vanderschuren; Isabel Moreno; Anjanappa, Ravi B.; Ima M Zainuddin; Wilhelm Gruissem

    2012-01-01

    Cassava brown streak disease (CBSD) and cassava mosaic disease (CMD) are currently two major viral diseases that severely reduce cassava production in large areas of Sub-Saharan Africa. Natural resistance has so far only been reported for CMD in cassava. CBSD is caused by two virus species, Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV). A sequence of the CBSV coat protein (CP) highly conserved between the two virus species was used to demonstrate that a CBSV...

  19. Cassava is not a goitrogen in mice

    International Nuclear Information System (INIS)

    To examine the effect of cassava on the thyroid function of mice, the authors fed fresh cassava root to mice and compared this diet with low iodine diet and Purina. Cassava provided a low iodine intake and increased urine thiocyanate excretion and serum thiocyanate levels. Mice on cassava lost weight. The thyroid glands of mice on cassava were not enlarged, even when normalized for body weight. The 4- and 24-hr thyroid uptakes of mice on cassava were similar to those of mice on low iodine diets. Protein-bound [125I]iodine at 24 hr was high in mice on either the cassava or low iodine diets. The thyroid iodide trap (T/M) was similar in mice on cassava and low iodine diets. When thiocyanate was added in vitro to the incubation medium, T/M was reduced in all groups of mice; under these conditions, thiocyanate caused a dose-related inhibition of T/M. The serum thyroxine (T4) and triiodothyronine (T3) concentrations of mice on cassava were reduced compared with mice on Purina diet. Thyroid T4 and T3 contents of mice on cassava were relatively low compared with mice on Purina diet. Hepatic T3 content and T4 5'-monodeiodination in liver homogenates were reduced in mice on cassava compared with other groups. The data show that cassava does not cause goiter in mice. The thiocyanate formed from ingestation of cassava is insufficient to inhibit thyroid iodide transport or organification of iodide. The cassava diet leads to rapid turnover of hormonal iodine because it is a low iodine diet. It also impairs 5'-monodeiodination of T4 which may be related to nutritional deficiency. These data in mice do not support the concept that cassava per se has goitrogenic action in man

  20. A Comparative Study of Some Properties of Cassava and Tree Cassava Starch Films

    Science.gov (United States)

    Belibi, P. C.; Daou, T. J.; Ndjaka, J. M. B.; Nsom, B.; Michelin, L.; Durand, B.

    Cassava and tree cassava starch films plasticized with glycerol were produced by casting method. Different glycerol contents (30, 35, 40 and 45 wt. % on starch dry basis) were used and the resulting films were fully characterized. Their water barrier and mechanical properties were compared. While increasing glycerol concentration, moisture content, water solubility, water vapour permeability, tensile strength, percent elongation at break and Young's modulus decreased for both cassava and tree cassava films. Tree cassava films presented better values of water vapour permeability, water solubility and percent elongation at break compared to those of cassava films, regardless of the glycerol content.

  1. Effect of Cassava Flour Characteristics on Properties of Cassava-Wheat-Maize Composite Bread Types

    Directory of Open Access Journals (Sweden)

    Maria Eduardo

    2013-01-01

    Full Text Available Replacement of wheat flour by other kinds of flour in bread making is economically important in South East Africa as wheat is mainly an imported commodity. Cassava is widely available in the region, but bread quality is impaired when large amounts of cassava are used in the bread formulation. Effect of differently processed cassavas (sun-dried, roasted and fermented on composite cassava-wheat-maize bread quality containing cassava levels from 20 to 40% (w/w was evaluated in combination with high-methylated pectin (HM-pectin added at levels of 1 to 3% (w/w according to a full factorial design. Addition of pectin to cassava flour made it possible to bake bread with acceptable bread quality even at concentration as high as 40%. In addition to cassava concentration, the type of cassava flour had the biggest effect on bread quality. With high level of cassava, bread with roasted cassava had a higher volume compared with sun-dried and fermented. The pectin level had a significant effect on improving the volume in high level roasted cassava bread. Crumb firmness similar to wheat bread could be obtained with sun-dried and roasted cassava flours. Roasted cassava bread was the only bread with crust colour similar to wheat bread.

  2. Sensorial evolution of cassava flour (Manihot esculenta crantz) added to protein concentrate cassava leaves.

    Science.gov (United States)

    Lima, Elaine C S; Feijo, Márcia B S; Freitas, Maria C J; Dos Santos, Edna R; Sabaa-Srur, Armando U O; Moura, Luciana S M

    2013-09-01

    Cassava is regarded as the nutritional base of populations in developing countries, and flour, product made of cassava, is the most consumed in the world. The cassava leaves are very rich in vegetable proteins, but a big amount is lost in processing the crop. The objective of this study was to do a sensory evaluation of cassava flour to which a protein concentrate obtained from cassava leaves (CPML) was added. The CPML was obtained from cassava leaves by isoelectric precipitation and added to cassava paste for preparation of flour in three parts 2.5, 5, and 10%. The acceptance test was done by 93 consumers of flour, using hedonic scale of 7 points to evaluate characteristics like color, scent, flavor, bitterness, texture, and overall score. By the method of quantitative descriptive analysis (QDA), eight trained tasters evaluated the following characteristics: whitish color, greenish color, cassava flavor, bitter flavor, characteristic flavor, lumpiness, raw texture, leaf scent, and cassava scent. The acceptability test indicated that flour cassava with 2.5 was preferred. Whitish color, greenish color, cassava flavor, bitter flavor, salty flavor, characteristic flavor, lumpiness texture, raw texture, and the smell of the leaves and cassava flour were the main descriptors defined for flour cassava with CPML has better characteristics. PMID:24804041

  3. Sensorial evolution of cassava flour (Manihot esculenta crantz) added to protein concentrate cassava leaves.

    Science.gov (United States)

    Lima, Elaine C S; Feijo, Márcia B S; Freitas, Maria C J; Dos Santos, Edna R; Sabaa-Srur, Armando U O; Moura, Luciana S M

    2013-09-01

    Cassava is regarded as the nutritional base of populations in developing countries, and flour, product made of cassava, is the most consumed in the world. The cassava leaves are very rich in vegetable proteins, but a big amount is lost in processing the crop. The objective of this study was to do a sensory evaluation of cassava flour to which a protein concentrate obtained from cassava leaves (CPML) was added. The CPML was obtained from cassava leaves by isoelectric precipitation and added to cassava paste for preparation of flour in three parts 2.5, 5, and 10%. The acceptance test was done by 93 consumers of flour, using hedonic scale of 7 points to evaluate characteristics like color, scent, flavor, bitterness, texture, and overall score. By the method of quantitative descriptive analysis (QDA), eight trained tasters evaluated the following characteristics: whitish color, greenish color, cassava flavor, bitter flavor, characteristic flavor, lumpiness, raw texture, leaf scent, and cassava scent. The acceptability test indicated that flour cassava with 2.5 was preferred. Whitish color, greenish color, cassava flavor, bitter flavor, salty flavor, characteristic flavor, lumpiness texture, raw texture, and the smell of the leaves and cassava flour were the main descriptors defined for flour cassava with CPML has better characteristics.

  4. Commercial Dynamics in Zambia’s Cassava Value Chain

    OpenAIRE

    Haggblade, Steven; Nyembe, Misheck

    2008-01-01

    Cassava production has grown rapidly in Zambia since the early 1990’s. Available evidence suggests that volumes of traded cassava have been increasing roughly twice as fast as production. Yet this cassava production boom could stall unless commercial markets for it develop. To help accelerate commercial development of cassava and cassava-based products at the national level, Zambia’s Agricultural Consultative Forum (ACF) initiated an Acceleration of Cassava Utilization (ACU) Task Force, begin...

  5. Solid Substrate Fermentation of Cassava Peel for Poultry Feed Ingredient

    OpenAIRE

    Stephanie; Purwadaria T

    2013-01-01

    Cassava peel which is not used during cassava starch extraction is one of potential resources for animal feed. However, cassava peel has low level protein content, high level crude fiber, and high level of toxic cyanogenic compound. These problems limit the utilization of cassava peel as feed. Solid substrate fermentation using mold may be a solution process to increase its nutritional value and decrease toxic level of cassava peel. In this paper, matters that related with cassava peel fermen...

  6. Cassava virus diseases: biology, epidemiology, and management.

    Science.gov (United States)

    Legg, James P; Lava Kumar, P; Makeshkumar, T; Tripathi, Leena; Ferguson, Morag; Kanju, Edward; Ntawuruhunga, Pheneas; Cuellar, Wilmer

    2015-01-01

    Cassava (Manihot esculenta Crantz.) is the most important vegetatively propagated food staple in Africa and a prominent industrial crop in Latin America and Asia. Its vegetative propagation through stem cuttings has many advantages, but deleteriously it means that pathogens are passed from one generation to the next and can easily accumulate, threatening cassava production. Cassava-growing continents are characterized by specific suites of viruses that affect cassava and pose particular threats. Of major concern, causing large and increasing economic impact in Africa and Asia are the cassava mosaic geminiviruses that cause cassava mosaic disease in Africa and Asia and cassava brown streak viruses causing cassava brown streak disease in Africa. Latin America, the center of origin and domestication of the crop, hosts a diverse set of virus species, of which the most economically important give rise to cassava frog skin disease syndrome. Here, we review current knowledge on the biology, epidemiology, and control of the most economically important groups of viruses in relation to both farming and cultural practices. Components of virus control strategies examined include: diagnostics and surveillance, prevention and control of infection using phytosanitation, and control of disease through the breeding and promotion of varieties that inhibit virus replication and/or movement. We highlight areas that need further research attention and conclude by examining the likely future global outlook for virus disease management in cassava.

  7. Genetic modification of cassava enhances starch production

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    @@ Recently, a field test of transgenic cassava (Manihot esculenta Crantz) for enhanced starch production by the Shanghai Institute of Plant Physiology & Ecology (SIPPE), the CAS Shanghai Institutes for Biological Sciences, proved successful. Through application of transgenic technologies in cassava, the starch quality of this tropical root crop was largely improved. The new cassava cultivars are believed to have a tremendous potential for industrial application in the future.

  8. Bemisia tabaci (Homoptera: Aleyrodidae) and Indian cassava mosaic virus transmission

    Science.gov (United States)

    Bemisia tabaci (Gennadius) adults from colonies reared on cassava or sweet potato plants were studied to determine their ability to transmit Indian cassava mosaic virus (ICMV) (Geminiviridae: Begomovirus) from cassava to cassava. Virus acquisition access (feeding) periods (AAP) of 48 h on ICMV-infec...

  9. Strategies for developing the cassava industry

    International Nuclear Information System (INIS)

    The centralization of the cassava industry in tropical (and especially African) countries should be considered as a very important part of general strategy directed to the provision of the population with nutritionally balanced cassava foods. The Irish model of the development of dairy industry during the last 45 years had been a classical example of small involved groups in dairy farming getting together to pool their resources and family requirements to make a common objective succeed. This model based on a co-operative concept could be recommended for the cassava producing areas in order to improve this industry. The identification of the research areas required to improve the quality of the cassava fermented food products is another important part of the cassava strategy. These areas should include (i) fundamental studies of the various bacterial groups involved in the fermentation process and identification of the key groups involved at the various stages of fermentation (ii) strain screening programmes of these identified bacteria to select those which are most important to the fermentation of cassava (iii) studies to determine the appropriate methods for the propagation and the storage of these strains and (iv) systems to distribute these strains to the industries/small farmers/local co-operatives in cassava processing. Other technological and research aspects of improvement of the traditional fermentation practice of cassava are discussed in the paper. (author)

  10. Cassava Mutation Breeding: Current Status and Trends

    International Nuclear Information System (INIS)

    Cassava (Manihot esculenta Crantz) is an important energy source in the diets of millions of people in the tropical and subtropical regions of the world, especially the poor. Also its industrial uses are steadily growing for starch, animal feed and bio-ethanol. Although it has high economic and social relevance, few major scientific efforts have been made to improve the crop until the 1970s. With the goals and objectives of cassava improvement through breeding, different strategies have been developed during the last several decades, such as evaluation and selection of the local landraces, introduced germplasm (as clones or segregating F1 population), hybridization (including inbreeding by both recurrent back-cross schemes and double haploids (DH)), interspecific hybridization, polyploidy breeding, genetic transformation, use of molecular markers and mutation breeding. Induced mutation breeding on cassava has been explored in the last several decades with few published papers. Yet, the production of novel genotypes, such as high amylose and small granule mutants and mutants with tolerance to post harvest physiological deterioration (PPD), has been reported. These results suggest that mutagenesis could be an effective alternative for cassava breeding. However, many drawbacks still exist in cassava mutation breeding, such as the occurrence of chimeras. Validated and developing protocols for different biotechnologies, such as TILLING protocol, cassava genome sequencing and cassava somatic embryogenesis, will significantly ameliorate the drawbacks to traditional mutation breeding, and consequently aid the routine application of induced mutation in both cassava improvement and in gene discovery and elucidation. (author)

  11. Fermented cassava waste and its utilization in broiler chickens rations

    OpenAIRE

    Supriyati,

    2003-01-01

    Cassava waste is a by-product of cassava flour industry and its amount is increasing following the increasing of cassava flour industry. Its utilization as a feedstuff, is limited by its low protein content. The cassava waste is only utilized as the energy source. One of the alternative technology in improving the utilization of cassava waste as a feedstuff, by improving the nutritive value through fermentation process. Fermentation was carried out by solid substrate fermentation using Asperg...

  12. Cassava diet--a cause for mucopolysaccharidosis?

    Science.gov (United States)

    Sreeja, V G; Leelamma, S

    2002-01-01

    Studies were carried out to determine the changes in glycosaminnoglycan (GAG) metabolism in rats fed cassava with varying cyanoglucoside levels and two levels of protein. Results indicated that there was an enhancement in the level of total and individual GAG with a corresponding reduction in the activity of enzymes involved in the degradation of glycosaminoglycan. These changes were significant for rats given a cassava diet (raw and boiled cassava) and low protein. The changes in total and individual GAG and the decrease in the activity of degrading enzymes was more for high cyanide (raw cassava) groups compared with other groups showing that consumption of untreated cassava is an additive factor for the promotion of mucopolysaccharidosis. PMID:12049146

  13. Cassava starch in the Brazilian food industry

    Directory of Open Access Journals (Sweden)

    Ivo Mottin Demiate

    2011-06-01

    Full Text Available Cassava starch is a valued raw material for producing many kinds of modified starches for food applications. Its physicochemical properties, as well as its availability, have made it an interesting and challenging ingredient for the food industry. In the present work, food grade modified cassava starches were purchased from producers and analyzed for selected physicochemical characteristics. Samples of sour cassava starch were included, as well as one sample of native cassava starch. Results showed that almost all modified starches were resistant to syneresis, produced pastes more stable to stirred cooking, and some of them were difficult to cook. The sour cassava starches presented high acidity and resulted in clear and unstable pastes during stirred cooking, susceptible to syneresis.

  14. Solid Substrate Fermentation of Cassava Peel for Poultry Feed Ingredient

    Directory of Open Access Journals (Sweden)

    Stephanie

    2013-03-01

    Full Text Available Cassava peel which is not used during cassava starch extraction is one of potential resources for animal feed. However, cassava peel has low level protein content, high level crude fiber, and high level of toxic cyanogenic compound. These problems limit the utilization of cassava peel as feed. Solid substrate fermentation using mold may be a solution process to increase its nutritional value and decrease toxic level of cassava peel. In this paper, matters that related with cassava peel fermentation process are subsequently described, namely: (i problems of cassava peel; (ii biodegradation and detoxification process; (iii solid state fermentation methods on cassava peel; (iv nutritional quality of fermented cassava peel; and (v application of fermented cassava peel in poultry feed. The fermented cassava peel application is compared with those of cassava root and waste (onggok. Addition of nitrogen inorganic in the fermentation process increases the mold growth and protein content of the product, while fiber and cyanogenic contents are decreased due to mold degradation activity. The fermentation process may be carried out using only the cassava peel as the substrate or mixed with wheat flour, using indigenous microbes, Aspergillus niger or a white rot fungus, Panus tigrinus as inoculum. As well as fermented cassava root and waste, fermented cassava peel can be used to substitute maize as poultry feed, although it is reported that the optimum substitution in broiler ration is only 10%.

  15. Cassava; African perspective on space agriculture

    Science.gov (United States)

    Katayama, Naomi; Njemanze, Philip; Nweke, Felix; Space Agriculture Task Force, J.; Katayama, Naomi; Yamashita, Masamichi

    Looking on African perspective in space agriculture may contribute to increase diversity, and enforce robustness for advanced life support capability. Cassava, Manihot esculentaand, is one of major crop in Africa, and could be a candidate of space food materials. Since resource is limited for space agriculture in many aspects, crop yield should be high in efficiency, and robust as well. The efficiency is measured by farming space and time. Harvest yield of cassava is about 41 MJ/ m2 (70 ton/ha) after 11 months of farming. Among rice, wheat, potato, and sweet potato, cassava is ranked to the first place (40 m2 ) in terms of farming area required to supply energy of 5 MJ/day, which is recommended for one person. Production of cassava could be made under poor condition, such as acidic soil, shortage of fertilizer, draught. Laterite, similar to Martian regolith. Propagation made by stem cutting is an advantage of cassava in space agriculture avoiding entomophilous or anemophilous process to pollinate. Feature of crop storage capability is additional factor that determines the efficiency in the whole process of agriculture. Cassava root tuber can be left in soil until its consumption. Cassava might be an African contribution to space agriculture.

  16. Cassava based diets for sustainable ruminant production

    International Nuclear Information System (INIS)

    Cassava (Manihot esculenta, Crantz) is an annual crop grown widely in the tropical regions of Africa, Asia and Latin America. It thrives in sandy-loam soils with low organic matter and in climate with low rainfall and high temperature. Cassava could also response more with manure fertilization. Cassava tubers contain high levels of energy and minimal levels of crude protein, have been used as readily fermentable energy in ruminant rations, and have been used extensively as a feed for livestock. Recent attempts have been made to develop new products using cassava chips as an energy source with urea as non-protein nitrogen (NPN). Two new cassava based products have been developed: cassarea and cassaya. Cassarea was formulated to contain the following ingredients: 57.1% Cassava chips + 9.9% urea and 3% tallow (Cassarea I, 30% CP); 83.6% Cassava chips + 13.4% urea and 3% tallow (Cassarea II, 40% CP); 80.2% Cassava chips + 16.8% urea and 3% tallow (Cassarea III, 50% CP). Cassarea was tested for rumen degradability using the nylon bag technique and was found to have a 46.2 to 56.7% effective DM degradability. Further investigations with Cassarea II (40% CP) showed that it could be used to replace SBM in the rations of lactating cows, but supplementation with a rumen by-pass protein such as cottonseed meal would be recommended. Cassaya (30% CP) is a product formulated using chopped whole cassava crop hay (85%) + soybean meal (5%) + cassava chips (5%) + urea (2%) + tallow (2%) + sulphur (1%), mixing with water, pressed through a pelleting machine and sun-dried to at least 85% DM. The use of Cassaya in lactating dairy cows as a protein source proved to be efficient in promoting rumen fermentation, improved milk yield and composition and providing an increased economical return. Moreover, cassava hay (CH) has been applied in ruminant nutrition as a high-quality protein supplement for dairy cattle, beef and buffalo production. CH consists of whole crop of cassava harvested at

  17. RNAi-mediated resistance to Cassava brown streak Uganda virus in transgenic cassava.

    Science.gov (United States)

    Yadav, Jitender S; Ogwok, Emmanuel; Wagaba, Henry; Patil, Basavaprabhu L; Bagewadi, Basavaraj; Alicai, Titus; Gaitan-Solis, Eliana; Taylor, Nigel J; Fauquet, Claude M

    2011-09-01

    Cassava brown streak disease (CBSD), caused by Cassava brown streak Uganda virus (CBSUV) and Cassava brown streak virus (CBSV), is of new epidemic importance to cassava (Manihot esculenta Crantz) production in East Africa, and an emerging threat to the crop in Central and West Africa. This study demonstrates that at least one of these two ipomoviruses, CBSUV, can be efficiently controlled using RNA interference (RNAi) technology in cassava. An RNAi construct targeting the near full-length coat protein (FL-CP) of CBSUV was expressed constitutively as a hairpin construct in cassava. Transgenic cassava lines expressing small interfering RNAs (siRNAs) against this sequence showed 100% resistance to CBSUV across replicated graft inoculation experiments. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis showed the presence of CBSUV in leaves and some tuberous roots from challenged controls, but not in the same tissues from transgenic plants. This is the first demonstration of RNAi-mediated resistance to the ipomovirus CBSUV in cassava.

  18. Electrical and absorption properties of fresh cassava tubers and cassava starch

    Science.gov (United States)

    Harnsoongnoen, S.; Siritaratiwat, A.

    2015-09-01

    The objective of this study was to analyze the electrical and absorption properties of fresh cassava tubers and cassava starch at various frequencies using electric impedance spectroscopy and near-infrared spectroscopy, as well as determine the classification of the electrical parameters of both materials using the principle component analysis (PCA) method. All samples were measured at room temperature. The electrical and absorption parameters consisted of dielectric constant, dissipation factor, parallel capacitance, resistance, reactance, impedance and absorbance. It was found that the electrical and absorption properties of fresh cassava tubers and cassava starch were a function of frequency, and there were significant differences between the materials. The dielectric constant, parallel capacitance, resistance and impedance of fresh cassava tubers and cassava starch had similar dramatic decreases with increasing frequency. However, the reactance of both materials increased with an increasing frequency. The electrical parameters of both materials could be classified into two groups. Moreover, the dissipation factor and phase of impedance were the parameters that could be used in the separation of both materials. According to the absorbance patterns of the fresh cassava tubers and cassava starch, there were significant differences.

  19. Electrical and absorption properties of fresh cassava tubers and cassava starch

    International Nuclear Information System (INIS)

    The objective of this study was to analyze the electrical and absorption properties of fresh cassava tubers and cassava starch at various frequencies using electric impedance spectroscopy and near-infrared spectroscopy, as well as determine the classification of the electrical parameters of both materials using the principle component analysis (PCA) method. All samples were measured at room temperature. The electrical and absorption parameters consisted of dielectric constant, dissipation factor, parallel capacitance, resistance, reactance, impedance and absorbance. It was found that the electrical and absorption properties of fresh cassava tubers and cassava starch were a function of frequency, and there were significant differences between the materials. The dielectric constant, parallel capacitance, resistance and impedance of fresh cassava tubers and cassava starch had similar dramatic decreases with increasing frequency. However, the reactance of both materials increased with an increasing frequency. The electrical parameters of both materials could be classified into two groups. Moreover, the dissipation factor and phase of impedance were the parameters that could be used in the separation of both materials. According to the absorbance patterns of the fresh cassava tubers and cassava starch, there were significant differences

  20. The BioCassava Plus program: Biofortification of cassava for sub-Saharan Africa

    Science.gov (United States)

    More than 250 million Africans rely on the starchy root crop cassava (Manihot esculenta) as their staple source of calories. A typical cassava-based diet, however, provides less than 30% of the minimum daily requirement for protein and only 10-20% of that for iron, zinc, and vitamin A. The BioCassav...

  1. Consumer preferences for table cassava characteristics in Pernambuco, Brazil

    OpenAIRE

    Gonzalez, Carolina; Johnson, Nancy L.

    2009-01-01

    Cassava is a major source of carbohydrate for populations in the tropics; however, there is little information about the preferences of consumers toward the quality characteristics of this crop. This paper analyzes the demand for different cassava attributes, and applies the hedonic price method to estimate the values that consumers give to implicit attributes of cassava. The results show that ease of peeling, time of cooking and texture of cassava are the most important characteristics consu...

  2. Phenotypic Approaches to Drought in Cassava: Review

    Directory of Open Access Journals (Sweden)

    Emmanuel eOkogbenin

    2013-05-01

    Full Text Available Cassava is an important crop in Africa, Asia, Latin America and the Caribbean. Cassava can be produced adequately in drought conditions making it the ideal food security crop in marginal environments. Although cassava can tolerate drought stress, it can be genetically improved to enhance productivity in such environments. Drought adaptation studies in over three decades in cassava have identified relevant mechanisms which have been explored in conventional breeding. Drought is a quantitative trait and its multigenic nature makes it very challenging to effectively manipulate and combine genes in breeding for rapid genetic gain and selection process. Cassava has a long growth cycle of 12 - 18 months which invariably contributes to a long breeding scheme for the crop. Modern breeding using advances in genomics and improved genotyping, is facilitating the dissection and genetic analysis of complex traits including drought tolerance, thus helping to better elucidate and understand the genetic basis of such traits. A beneficial goal of new innovative breeding strategies is to shorten the breeding cycle using minimized, efficient or fast phenotyping protocols. While high throughput genotyping have been achieved, this is rarely the case for phenotyping for drought adaptation. Some of the storage root phenotyping in cassava are often done very late in the evaluation cycle making selection process very slow. This paper highlights some modified traits suitable for early-growth phase phenotyping that may be used to reduce drought phenotyping cycle in cassava. Such modified traits can significantly complement the high throughput genotyping procedures to fast track breeding of improved drought tolerant varieties. The need for metabolite profiling, improved phenomics to take advantage of next generation sequencing technologies and high throughput phenotyping are basic steps for future direction to improve genetic gain and maximize speed for drought tolerance

  3. Phenotypic approaches to drought in cassava: review.

    Science.gov (United States)

    Okogbenin, Emmanuel; Setter, Tim L; Ferguson, Morag; Mutegi, Rose; Ceballos, Hernan; Olasanmi, Bunmi; Fregene, Martin

    2013-01-01

    Cassava is an important crop in Africa, Asia, Latin America, and the Caribbean. Cassava can be produced adequately in drought conditions making it the ideal food security crop in marginal environments. Although cassava can tolerate drought stress, it can be genetically improved to enhance productivity in such environments. Drought adaptation studies in over three decades in cassava have identified relevant mechanisms which have been explored in conventional breeding. Drought is a quantitative trait and its multigenic nature makes it very challenging to effectively manipulate and combine genes in breeding for rapid genetic gain and selection process. Cassava has a long growth cycle of 12-18 months which invariably contributes to a long breeding scheme for the crop. Modern breeding using advances in genomics and improved genotyping, is facilitating the dissection and genetic analysis of complex traits including drought tolerance, thus helping to better elucidate and understand the genetic basis of such traits. A beneficial goal of new innovative breeding strategies is to shorten the breeding cycle using minimized, efficient or fast phenotyping protocols. While high throughput genotyping have been achieved, this is rarely the case for phenotyping for drought adaptation. Some of the storage root phenotyping in cassava are often done very late in the evaluation cycle making selection process very slow. This paper highlights some modified traits suitable for early-growth phase phenotyping that may be used to reduce drought phenotyping cycle in cassava. Such modified traits can significantly complement the high throughput genotyping procedures to fast track breeding of improved drought tolerant varieties. The need for metabolite profiling, improved phenomics to take advantage of next generation sequencing technologies and high throughput phenotyping are basic steps for future direction to improve genetic gain and maximize speed for drought tolerance breeding. PMID

  4. An atlas of cassava in Africa : historical, agroecological and demographic aspects of crop distribution

    NARCIS (Netherlands)

    Carter, S.; Fresco, L.O.; Jones, P.

    1992-01-01

    This book contains 6 chapters covering: the dynamics of cassava in Africa; the introduction and diffusion of cassava in Africa; current distribution of cassava in Africa; the relationship of cassava distribution to environment and population; distribution and change in cassava production in Nigeria,

  5. Sequences enhancing cassava mosaic disease symptoms occur in the cassava genome and are associated with South African cassava mosaic virus infection.

    Science.gov (United States)

    Maredza, A T; Allie, F; Plata, G; Rey, M E C

    2016-06-01

    Cassava is an important food security crop in Sub-Saharan Africa. Two episomal begomovirus-associated sequences, named Sequences Enhancing Geminivirus Symptoms (SEGS1 and SEGS2), were identified in field cassava affected by the devastating cassava mosaic disease (CMD). The sequences reportedly exacerbated CMD symptoms in the tolerant cassava landrace TME3, and the model plants Arabidopsis thaliana and Nicotiana benthamiana, when biolistically co-inoculated with African cassava mosaic virus-Cameroon (ACMV-CM) or East African cassava mosaic virus-UG2 (EACMV-UG2). Following the identification of small SEGS fragments in the cassava EST database, the intention of this study was to confirm their presence in the genome, and investigate a possible role for these sequences in CMD. We report that multiple copies of varying lengths of both SEGS1 and SEGS2 are widely distributed in the sequenced cassava genome and are present in several other cassava accessions screened by PCR. The endogenous SEGS1 and SEGS2 are in close proximity or overlapping with cassava genes, suggesting a possible role in regulation of specific biological processes. We confirm the expression of SEGS in planta using EST data and RT-PCR. The sequence features of endogenous SEGS (iSEGS) are unique but resemble non-autonomous transposable elements (TEs) such as MITEs and helitrons. Furthermore, many SEGS-associated genes, some involved in virus-host interactions, are differentially expressed in susceptible (T200) and tolerant TME3) cassava landraces infected by South African cassava mosaic virus (SACMV) of susceptible (T200) and tolerant (TME3) cassava landraces. Abundant SEGS-derived small RNAs were also present in mock-inoculated and SACMV-infected T200 and TME3 leaves. Given the known role of TEs and associated genes in gene regulation and plant immune responses, our observations are consistent with a role of these DNA elements in the host's regulatory response to geminiviruses.

  6. Sequences enhancing cassava mosaic disease symptoms occur in the cassava genome and are associated with South African cassava mosaic virus infection.

    Science.gov (United States)

    Maredza, A T; Allie, F; Plata, G; Rey, M E C

    2016-06-01

    Cassava is an important food security crop in Sub-Saharan Africa. Two episomal begomovirus-associated sequences, named Sequences Enhancing Geminivirus Symptoms (SEGS1 and SEGS2), were identified in field cassava affected by the devastating cassava mosaic disease (CMD). The sequences reportedly exacerbated CMD symptoms in the tolerant cassava landrace TME3, and the model plants Arabidopsis thaliana and Nicotiana benthamiana, when biolistically co-inoculated with African cassava mosaic virus-Cameroon (ACMV-CM) or East African cassava mosaic virus-UG2 (EACMV-UG2). Following the identification of small SEGS fragments in the cassava EST database, the intention of this study was to confirm their presence in the genome, and investigate a possible role for these sequences in CMD. We report that multiple copies of varying lengths of both SEGS1 and SEGS2 are widely distributed in the sequenced cassava genome and are present in several other cassava accessions screened by PCR. The endogenous SEGS1 and SEGS2 are in close proximity or overlapping with cassava genes, suggesting a possible role in regulation of specific biological processes. We confirm the expression of SEGS in planta using EST data and RT-PCR. The sequence features of endogenous SEGS (iSEGS) are unique but resemble non-autonomous transposable elements (TEs) such as MITEs and helitrons. Furthermore, many SEGS-associated genes, some involved in virus-host interactions, are differentially expressed in susceptible (T200) and tolerant TME3) cassava landraces infected by South African cassava mosaic virus (SACMV) of susceptible (T200) and tolerant (TME3) cassava landraces. Abundant SEGS-derived small RNAs were also present in mock-inoculated and SACMV-infected T200 and TME3 leaves. Given the known role of TEs and associated genes in gene regulation and plant immune responses, our observations are consistent with a role of these DNA elements in the host's regulatory response to geminiviruses. PMID:25920485

  7. Improvement of cassava for resistance to insect pests and diseases

    International Nuclear Information System (INIS)

    The African cassava mosaic virus and cassava mealybug are devastating the cassava crop in Uganda. Because of the severe widespread occurrence of the virus and mealybug, in vitro cultured cassava plantlets instead of stem cuttings will be irradiated. In addition, the project has incorporated sweet potato. Installation of tissue culture laboratory at Namulonge was completed in early 1993. Work is in progress to establish efficient in vitro culture micropropagation techniques for the two crops. Small numbers of cassava plantlets of varieties 'TMS 30337' and 'TMS 4(2)1425' and sweet potato entry 30 are in vitro culture. Mass irradiation of plantlets is planned in future. (author). 4 refs

  8. Gene expression of beta carotene genes in transgenic biofortified cassava

    OpenAIRE

    Telengech, P. K.; Maling’a, J. N.; Nyende, A. B.; Gichuki, S. T.; Wanjala, B. W.

    2014-01-01

    Cassava is an important food for millions of people around the world. However, cassava is deficient in protein, iron, zinc, pro-vitamin A and vitamin E. Cassava biofortified with pro-vitamin A can help reduce Vitamin A Deficiency among the undernourished communities that rely upon it for sustenance. BioCassava Plus project has developed transgenic cassava that expresses beta carotene in roots using root specific patatin promoter. This study aimed at confirming expression of nptII, crtB and DX...

  9. Study of Products Distilled Spirits with Cassava Dregs

    Institute of Scientific and Technical Information of China (English)

    WANG le; WANG Jun-gao; LIU Wen-long

    2009-01-01

    In this paper, Cassava dregs are an outgrowth produced during starchy production which uses cassava as raw material. It is usually dropped out or used as cheap feedstuff. In order to make the best use of cassava dregs, increase industries' benefits and reduce castoff this study developed a new technique which used cassava dregs as raw material to produce distilled spirits based on cassava dregs characteristics. The technique adopt solid-ferment procedure. At first, the ferment is processed by solid-state distilling, and then rectification extra care refinement: at last the tequila was produced with characteristics of simple and elegant fragrance and mellow-tasting.

  10. Chemical safety of cassava products in regions adopting cassava production and processing - experience from Southern Africa

    DEFF Research Database (Denmark)

    Nyirenda, D.B.; Chiwona-Karltun, L.; Chitundu, M.;

    2011-01-01

    The cassava belt area in Southern Africa is experiencing an unforeseen surge in cassava production, processing and consumption. Little documentation exists on the effects of this surge on processing procedures, the prevailing levels of cyanogenic glucosides of products consumed and the levels...... and perceptions concerning cassava and chemical food safety. Chips, mixed biscuits and flour, procured from households and markets in three regions of Zambia (Luapula-North, Western and Southern) as well as products from the Northern, Central and Southern regions of Malawi, were analyzed for total cyanogenic...

  11. A single-tube duplex and multiplex PCR for simultaneous detection of four cassava mosaic begomovirus species in cassava plants.

    Science.gov (United States)

    Aloyce, R C; Tairo, F; Sseruwagi, P; Rey, M E C; Ndunguru, J

    2013-04-01

    A single-tube duplex and multiplex PCR was developed for the simultaneous detection of African cassava mosaic virus (ACMV), East African cassava mosaic Cameroon virus (EACMCV), East African cassava mosaic Malawi virus (EACMMV) and East African cassava mosaic Zanzibar virus (EACMZV), four cassava mosaic begomoviruses (CMBs) affecting cassava in sub-Saharan Africa. Co-occurrence of the CMBs in cassava synergistically enhances disease symptoms and complicates their detection and diagnostics. Four primer pairs were designed to target DNA-A component sequences of cassava begomoviruses in a single tube PCR amplification using DNA extracted from dry-stored cassava leaves. Duplex and multiplex PCR enabled the simultaneous detection and differentiation of the four CMBs, namely ACMV (940bp), EACMCV (435bp), EACMMV (504bp) and EACMZV (260bp) in single and mixed infections, and sequencing results confirmed virus identities according to the respective published sequences of begomovirus species. In addition, we report here a modified Dellapotra et al. (1983) protocol, which was used to extract DNA from dry and fresh cassava leaves with comparable results. Using the duplex and multiplex techniques, time was saved and amount of reagents used were reduced, which translated into reduced cost of the diagnostics. This tool can be used by cassava breeders screening for disease resistance; scientists doing virus diagnostic studies; phytosanitary officers checking movement of diseased planting materials, and seed certification and multipliers for virus indexing.

  12. MOISTURE ISOTHERMS OF CASSAVA BAGASSE COMPOSITES IMPREGNATED WITH CASSAVA STARCH ACETATE SOLUTIONS

    Directory of Open Access Journals (Sweden)

    Kátia N. MATSUI

    2009-07-01

    Full Text Available

    The industrial processing of cassava to obtain starch generates a great variety of residues, with bagasse being the main solid residue produced. The improper disposal of this material represents an environmental problem and could be avoided by using this residue as a raw material to obtain biodegradable products. The bagasse produced during the process to obtain starch from cassava was used to prepare composites for disposable trays. Samples of the composites were impregnated with cassava starch acetate at atmospheric pressure and under vacuum condition. Moisture isotherms were determined and adjusted by GAB model. It was observed that the impregnation promoted an important decrease in sample higroscopicity, mainly at high relative humidities. These results suggest that starch acetate impregnation can be an alternative to water proofing biological materials like the composites obtained in this work. KEYWORDS: Cassava; bagasse; starch acetate; impregnation; isotherms.

  13. Emergence of a Latent Indian Cassava Mosaic Virus from Cassava Which Recovered from Infection by a Non-Persistent Sri Lankan Cassava Mosaic Virus

    Science.gov (United States)

    Karthikeyan, Chockalingam; Patil, Basavaprabhu L.; Borah, Basanta K.; Resmi, Thulasi R.; Turco, Silvia; Pooggin, Mikhail M.; Hohn, Thomas; Veluthambi, Karuppannan

    2016-01-01

    The major threat for cassava cultivation on the Indian subcontinent is cassava mosaic disease (CMD) caused by cassava mosaic geminiviruses which are bipartite begomoviruses with DNA A and DNA B components. Indian cassava mosaic virus (ICMV) and Sri Lankan cassava mosaic virus (SLCMV) cause CMD in India. Two isolates of SLCMV infected the cassava cultivar Sengutchi in the fields near Malappuram and Thiruvananthapuram cities of Kerala State, India. The Malappuram isolate was persistent when maintained in the Madurai Kamaraj University (MKU, Madurai, Tamil Nadu, India) greenhouse, whereas the Thiruvananthapuram isolate did not persist. The recovered cassava plants with the non-persistent SLCMV, which were maintained vegetative in quarantine in the University of Basel (Basel, Switzerland) greenhouse, displayed re-emergence of CMD after a six-month period. Interestingly, these plants did not carry SLCMV but carried ICMV. It is interpreted that the field-collected, SLCMV-infected cassava plants were co-infected with low levels of ICMV. The loss of SLCMV in recovered cassava plants, under greenhouse conditions, then facilitated the re-emergence of ICMV. The partial dimer clones of the persistent and non-persistent isolates of SLCMV and the re-emerged isolate of ICMV were infective in Nicotiana benthamiana upon agroinoculation. Studies on pseudo-recombination between SLCMV and ICMV in N. benthamiana provided evidence for trans-replication of ICMV DNA B by SLCMV DNA A. PMID:27690084

  14. Hyperglycemic effect of low protein cassava diet.

    Science.gov (United States)

    Sreeja, V G; Leelamma, S

    1998-03-01

    Hyperglycemic effect of cassava diet in presence of varying amounts of protein has been carried out. The rats fed a low protein high cyanide diet showed an increase in the blood glucose and a decrease in the liver glycogen. The activity of glycogen phosphorylase, glucose 6-phosphatase and phosphoglucomutase showed higher levels in the liver of low protein high cyanide group compared to the control group. Also, the activity of hexokinase, and isocitrate dehydrogenase activity in the liver of high cyanide low protein were significantly low. The results suggests that cassava diet with the low protein can induce hyperglycemia. PMID:9754064

  15. Microbial degradation and utilization of cassava peel.

    Science.gov (United States)

    Ofuya, C O; Nwajiuba, C J

    1990-06-01

    Cassava peel was readily degraded and utilized by a strain ofRhizopus growing in a solid-state fermentation. Growth was maximal at 45°C and was proportional to the degree of hydrolysis of the peel. The yield of biomass, as weight of dry mycellum from the reducing sugars of the peel, was 51%. After 72 h fermentation, the peel contained 76% moisture, 6% cellulose, 7% hemicellulose and 0.4% ash and the protein content had increased from 5.6% to 16%. These results suggest a possible economic value of cassava peel in the production of fungal biomass and feedstock.

  16. SCREENING OF CHEMICAL COMPOSITIONS OF CRUDE WATER EXTRACT OF DIFFERENT CASSAVA VARIETIES

    OpenAIRE

    Olajumoke Oke FAYINMINNU; Olubunmi Omowunmi FADINA; Alex Adeoluwa ADEDAPO

    2013-01-01

    Chemical composition of three sources of crude cassava water extract (CCWE) was evaluated in different varieties of cassava (MS6 Manihot Selection (local variety), TMS 30555 Tropical Manihot Selection (Improved variety) and Bulk (crude cassava water from cassava processing site). Crude cassava water extract from the pulp of cassava fresh roots was prepared and the chemical composition was determined in the analytical laboratory. The result of the analysis showed that, hydrocyanic acid (HCN) ...

  17. MOISTURE ISOTHERMS OF CASSAVA BAGASSE COMPOSITES IMPREGNATED WITH CASSAVA STARCH ACETATE SOLUTIONS

    OpenAIRE

    KáTIA N. MATSUI; FáBIO D. S. LAROTONDA; Alfredo T. N. Pires; JOãO B. LAURINDO

    2009-01-01

    The industrial processing of cassava to obtain starch generates a great variety of residues, with bagasse being the main solid residue produced. The improper disposal of this material represents an environmental problem and could be avoided by using this residue as a raw material to obtain biodegradable products. The bagasse produced during the process to obtain starch from cassava was used to prepare composites for disposable trays. Samples of the composites were imp...

  18. High-resolution mapping of resistance to cassava mosaic geminiviruses in cassava using genotyping-by-sequencing and its implications for breeding

    Science.gov (United States)

    Cassava mosaic disease (CMD), caused by different species of cassava mosaic geminiviruses (CMGs), is the most important disease of cassava in Africa and the Indian sub-continent. The cultivated cassava species is protected from CMD by polygenic resistance introgressed from the wild species Manihot g...

  19. The use of biolistic inoculation of cassava mosaic begomoviruses in screening cassava for resistance to cassava mosaic disease.

    Science.gov (United States)

    Ariyo, O A; Atiri, G I; Dixon, A G O; Winter, S

    2006-10-01

    Inoculation of cassava with infectious clones of cassava mosaic geminiviruses (Geminiviridae: Begomovirus) and total DNA extracts from plants infected with well-characterised viruses was evaluated using the Bio-Rad Helios Gene Gun System. Total DNA extracts from infected plants and cloned viruses were produced for coating gold particles and bombardment onto new cassava genotypes, 96/1089A, 96/1039, 96/0160, 96/0304 and three local landraces TME 117, TME 3 and TME 4. Cloned DNA of a Kenyan isolate of the recombinant variant of East African cassava mosaic virus (EACMV-UG2-[Ka]), was only infectious to TME 117 (7/10 plants), 3 weeks post-inoculation with mild infection symptoms in the newly developing leaves. Biolistic inoculation with a chimeric pseudorecombinant virus between DNA A and B components from EACMV-[Ke-Kilifi] and EACMV-UG2-[Ka], respectively, was infectious to TME 117, 96/1039 and 96/0304 and developed very severe and persistent symptoms. TME 3 and TME 4 also developed symptoms, 12 days post-inoculation (d.p.i.). Total DNA extracts of ACMV and EACMV-[Ke-Kilifi] resulted in serious infections with symptoms already evident, 10d.p.i. In general, biolistic inoculation trials with total DNA extracts resulted in a higher number of infected plants expressing symptoms at a much earlier stage (10-12d.p.i.) compared with trials inoculated with virus clones.

  20. The Cassava Genome: Current Progress, Future Directions.

    Science.gov (United States)

    Prochnik, Simon; Marri, Pradeep Reddy; Desany, Brian; Rabinowicz, Pablo D; Kodira, Chinnappa; Mohiuddin, Mohammed; Rodriguez, Fausto; Fauquet, Claude; Tohme, Joseph; Harkins, Timothy; Rokhsar, Daniel S; Rounsley, Steve

    2012-03-01

    The starchy swollen roots of cassava provide an essential food source for nearly a billion people, as well as possibilities for bioenergy, yet improvements to nutritional content and resistance to threatening diseases are currently impeded. A 454-based whole genome shotgun sequence has been assembled, which covers 69% of the predicted genome size and 96% of protein-coding gene space, with genome finishing underway. The predicted 30,666 genes and 3,485 alternate splice forms are supported by 1.4 M expressed sequence tags (ESTs). Maps based on simple sequence repeat (SSR)-, and EST-derived single nucleotide polymorphisms (SNPs) already exist. Thanks to the genome sequence, a high-density linkage map is currently being developed from a cross between two diverse cassava cultivars: one susceptible to cassava brown streak disease; the other resistant. An efficient genotyping-by-sequencing (GBS) approach is being developed to catalog SNPs both within the mapping population and among diverse African farmer-preferred varieties of cassava. These resources will accelerate marker-assisted breeding programs, allowing improvements in disease-resistance and nutrition, and will help us understand the genetic basis for disease resistance. PMID:22523606

  1. Recent advances in cassava pest management.

    Science.gov (United States)

    Bellotti, A C; Smith, L; Lapointe, S L

    1999-01-01

    Cassava (Manihot esculenta) occupies a uniquely important position as a food security crop for smallholder farmers in ares of the tropics where climate, soils, or societal stresses constrain production. Given its reliability and productivity, cassava is the most important locally produced food in a third of the world's low-income, food-deficit countries. It is the fourth most important source of carbohydrates for human consumption in the tropics, after rice, sugar, and maize. World production of cassava from 1994-1996 averaged 166 million tons/year grown on 16.6 million hectares (ha), for an average yield of 9.9 tons/ha. Approximately 57% is used for human consumption, 32% for animal feed and industrial purposes, and 11% is waste. Africa accounts for 51.3% of the production; Asia, 29.4%; and Latin America, 19.3%. The area planted to cassava in Africa, Asia, and Latin America is 10.3, 3.7, and 2.6 million ha, respectively.

  2. The Post-Genomic Era of Cassava

    Science.gov (United States)

    The genomics era revolutionized our efficiency at gathering and disseminating scientific information required for advancing our understanding of plant biology. In the case of cassava, the genomics revolution has not kept pace with other staple food and fiber crops important to global economies. As a...

  3. Economic Analysis of Cassava Production in Benue State, Nigeria

    Directory of Open Access Journals (Sweden)

    I.U. Odoemenem

    2011-09-01

    Full Text Available The study was undertaken to analyze the economics of cassava production in Benue State. Data for this study were collected from a sample of one hundred and sixteen small-scale cassava farmers randomly selected. The objectives of the study were to determine and rank the cost elements of cassava production in the study area; determine the returns to cassava production; and evaluate the profitability of cassava production in the study area. Socio-economic factors include age, educational background, marital status, sex, sources of labour, awareness of extension services, method of weed control, and method of farm land acquisition were identified. Data collected for the study were analyzed using descriptive and inferential statistics. The coefficient of determination (R2 is 0.616, suggesting that the used model has a high goodness of fit. Furthermore, the result of the statistical analysis shows that investing in cassava production enterprise is profitable.

  4. Public attitudes towards genetically modified provitamin A Cassava in Brazil

    OpenAIRE

    Gonzalez Rojas, María Carolina

    2010-01-01

    Cassava is a basic staple food crop with worldwide distribution, mainly in developing countries. A fundamental source of energy for the poor, cassava grows well on marginal soils and resists pests and drought. In Latin America, Brazil is the largest cassava producer and consumer. The crop is especially important in the northeastern (NE) part of the country, where poverty and malnutrition rates are higher than in the rest of the country. However, despite the crop?s dietary importance, relative...

  5. New challenges in the cassava transformation in Nigeria and Ghana:

    OpenAIRE

    Nweke, Felix

    2004-01-01

    "This paper describes the dramatic cassava transformation that has taken place in Nigeria and Ghana over the past 50 years. From a rural subsistence crop, cassava has become a major cash crop sold in urban markets, a source of livestock feed, industrial starch and urban convenience foods. This paper documents the key factors driving the cassava transformation in Nigeria and Ghana. Differences in timing, promotional efforts and performance provide an instructive contrast which helps to identif...

  6. Effect of chemical and mechanical weed control on cassava yield, soil quality and erosion under cassava cropping system

    Science.gov (United States)

    Islami, Titiek; Wisnubroto, Erwin; Utomo, Wani

    2016-04-01

    Three years field experiments were conducted to study the effect of chemical and mechanical weed control on soil quality and erosion under cassava cropping system. The experiment were conducted at University Brawijaya field experimental station, Jatikerto, Malang, Indonesia. The experiments were carried out from 2011 - 2014. The treatments consist of three cropping system (cassava mono culture; cassava + maize intercropping and cassava + peanut intercropping), and two weed control method (chemical and mechanical methods). The experimental result showed that the yield of cassava first year and second year did not influenced by weed control method and cropping system. However, the third year yield of cassava was influence by weed control method and cropping system. The cassava yield planted in cassava + maize intercropping system with chemical weed control methods was only 24 t/ha, which lower compared to other treatments, even with that of the same cropping system used mechanical weed control. The highest cassava yield in third year was obtained by cassava + peanuts cropping system with mechanical weed control method. After three years experiment, the soil of cassava monoculture system with chemical weed control method possessed the lowest soil organic matter, and soil aggregate stability. During three years of cropping soil erosion in chemical weed control method, especially on cassava monoculture, was higher compared to mechanical weed control method. The soil loss from chemical control method were 40 t/ha, 44 t/ha and 54 t/ha for the first, second and third year crop. The soil loss from mechanical weed control method for the same years was: 36 t/ha, 36 t/ha and 38 t/ha. Key words: herbicide, intercropping, soil organic matter, aggregate stability.

  7. Molecular analysis of differentially expressed genes during postharvest deterioration in cassava (Manihot esculenta Crantz) tuberous roots

    NARCIS (Netherlands)

    Huang, J.; Bachem, C.W.B.; Jacobsen, E.; Visser, R.

    2001-01-01

    One of the major problems for cassava is the rapid deterioration after harvesting cassava tuberous roots, which limits the possibilities for production and distribution of cassava in the world. Postharvest deterioration is an inherent problem for cassava since wounding and mechanical damage of the t

  8. Extrusion of blends of cassava leaves and cassava flour: physical characteristics of extrudates

    Directory of Open Access Journals (Sweden)

    Cristiane da Cunha Salata

    2014-09-01

    Full Text Available A cassava-based puffed snack was produced using a single screw extruder to determine the effect of the raw material composition (cassava leaf flour and moisture and the process parameters (extrusion temperature and screw speed on the physical characteristics of an extruded-expanded snack. A central composite rotational design, including four factors with 30 treatments, was used with the following as dependent variables: expansion index, specific volume, water solubility index, water absorption index, color (L*, a*, b*, and hardness. Under conditions of low moisture content (12 to 14%, low percentage of cassava leaf flour (2 to 4%, and intermediate conditions of extrusion temperature (100°C and screw speed (230rpm, it was possible to obtain puffed snack products with desirable characteristics.

  9. Comparative petiole anatomy of cassava (Manihot) species.

    Science.gov (United States)

    Graciano-Ribeiro, D; Hashimoto-Freitas, D Y; Nassar, N M A

    2016-01-01

    In this study, we describe the petiole anatomy of six wild cassava (Manihot) species, one hybrid, and two cultivars of Manihot esculenta, in order to identify their dominant anatomical patterns and relate them to possible adaptations to abiotic factors in the Cerrado biome. The median parts of several petiole samples were transversally and longitudinally sectioned and stained. The results include data for the taxonomic classification of the genus, including distinctive anatomical characteristics of hybrid varieties of cassava and wild species, such as the presence/absence of trichomes and a hypodermis, layer type and number in the cortex, number of vascular bundles, cell types in the pith, and type of organization. Morphological analysis revealed differences in length and shape of the petiole insertion. The presence of trichomes, a hypodermis, the amount and type of supporting tissue in the cortex, as well as gelatinous fibers, may be related to drought tolerance. PMID:26909917

  10. Rehydration characteristics and modeling of cassava chips

    Directory of Open Access Journals (Sweden)

    Ajala, A.S

    2015-05-01

    Full Text Available Cassava chips with dimension 4x2x0.2cm were re-hydrated in distilled water at 200C, 300C and 400C in a laboratory water bath. Kinetics of re-hydration was investigated using three different re-hydration models namely Peleg, exponential and Weibull. The pattern of water absorption was observed to be faster at the initial period of soaking. Higher temperature induces faster moisture absorption in the chips. Non linear regression analysis was used to fit in the experimental data and the coefficient of determination was found to be greater than 0.72 for all the models. The values of R2 , RMSE, MBE and reduced chi square showed that Weibull model best described the re-hydrating behaviour of the cassava chips.

  11. Anaerobic digestion of cassava starch factory effluent.

    Science.gov (United States)

    Manilal, V B; Narayanan, C S; Balagopalan, C

    1990-06-01

    Biomethanation of cassava starch factory effluent in a batch digester produced 130 l biogas/kg dry matter with an average melthane content of 59%. About 63% COD was removed during 60 days. In semicontinuous digesters, gas production was 3251/kg dry matter with a retention time of 33,3 days giving a COD reduction of 50%. Size of starter inoculum was important for good biogasification of the effluent.

  12. Properties of thermoplastic starch from cassave bagasse and cassava starch and their blends with poly (lactic acid).

    Science.gov (United States)

    Cassava bagasse is an inexpensive and broadly available waste byproduct from cassava starch production. It contains roughly 50% cassava starch along with mostly fiber and could be a valuable feedstock for various bioproducts. Cassava bagasse and cassava starch were used in this study to make fiber-r...

  13. Physiological causes of yield variation in Cassava (Manihot esculenta Crantz)

    NARCIS (Netherlands)

    Veltkamp, H.J.

    1985-01-01

    Cassava (Manihot esculenta Crantz) is an important crop in many parts of the tropics, being mainly cultivated for its storage roots. Farmers' yields are low and one of the constraints to higher yields is the lack of adequate clones. At the beginning of the 1970s an extensive cassava research program

  14. Fermented cassava waste and its utilization in broiler chickens rations

    Directory of Open Access Journals (Sweden)

    Supriyati

    2003-10-01

    Full Text Available Cassava waste is a by-product of cassava flour industry and its amount is increasing following the increasing of cassava flour industry. Its utilization as a feedstuff, is limited by its low protein content. The cassava waste is only utilized as the energy source. One of the alternative technology in improving the utilization of cassava waste as a feedstuff, by improving the nutritive value through fermentation process. Fermentation was carried out by solid substrate fermentation using Aspergillus niger as an inoculant and mixing with urea and ammonium sulphate as inorganic nitrogen sources. The nutritive value of the product was evaluated by feeding trial using 144 “Shaver Stabro” strain 3 days old chicks with 3 treatments i.e. 0 (control, 5.0 and 10.0% fermented cassava waste. The results showed that the true protein content of fermented cassava increased from 2.2 to 18.4%. The inclusion of fermented cassava waste up to 10% in chicken broiler ration for 4 weeks feeding did not affect the feed consumption, bodyweight gain, FCR, weight of liver and gibblets. All parameter results from 10% inclusion were not significantly different (P>0.05 with the control (0% inclusion.

  15. Primary and cyclic somatic embryogenesis in cassava (Manihot esculente Crantz).

    NARCIS (Netherlands)

    Raemakers, C.J.J.M.

    1993-01-01

    Cassava is one of the major food crops in the tropics. Several of the major problems in cassava can probably only be solved by breeding with cellular and molecular techniques, e.g., the introduction of specific genes (virus resistance, protein content, quality aspects and so on). These genes can be

  16. Cassava leaves as protein source for pigs in Central Vietnam

    NARCIS (Netherlands)

    2007-01-01

    The aim of the studies described in this thesis was to evaluate the use of cassava leaves as protein sources for pigs when used at high levels in the diet, either in fresh form or with simplified methods of processing. In twenty cassava varieties taken from the upper part of the plant at the root

  17. Biofortified yellow cassava and Vitamin A status of Kenyan children

    NARCIS (Netherlands)

    Talsma, E.F.; Brouwer, I.D.; Verhoef, Hans; Mbera, G.N.K.; Mwangi, A.M.; Demir, A.Y.; Maziya-Dixon, B.; Boy, Erick; Zimmermann, M.B.; Melse-Boonstra, Alida

    2016-01-01

    Background: Whereas conventional white cassava roots are devoid of provitamin A, biofortified yellow varieties are naturally rich in b-carotene, the primary provitamin A carotenoid. Objective: We assessed the effect of consuming yellow cassava on serum retinol concentration in Kenyan schoolchildr

  18. Development and application of transgenic technologies in cassava

    NARCIS (Netherlands)

    Taylor, N.; Chavarriaga, P.; Raemakers, C.J.J.M.; Sititunga, D.; Zhang, P.

    2004-01-01

    The capacity to integrate transgenes into the tropical root crop cassava (Manihot esculenta Crantz) is now established and being utilized to generate plants expressing traits of agronomic interest. The tissue culture and gene transfer systems currently employed to produce these transgenic cassava ha

  19. Evaluation of cryogenic procedures for cryopreservation of Cassava genotypes

    Science.gov (United States)

    Cassava (Manihot esculent Crantz) is a perennial plant widely grown in many tropical countries as one of the most important commercial crops. The global cassava production in 2009 was at 242 million tons. Because of its economic importance to a large number of developing world, the application of ad...

  20. Examining cassava's potential to enhance food security under climate change

    Science.gov (United States)

    Recent advances in the biofortification of cassava, a substantial yield gap and cassava's potential for increased productivity and its inherent potential to respond positively to globally increasing CO2 are synergistic and encouraging in an otherwise bleak global view of the future of food security ...

  1. Socio-economic Analysis of Cassava Marketing in Benue State, Nigeria

    OpenAIRE

    Benjamin C. Asogwa; J. A. C. Ezihe; Ater, P.I.

    2013-01-01

    The purpose of this study is to analyze the socio-economics of cassava marketing in Benue State, Nigeria. Data were collected from randomly sampled 107 cassava marketers in Benue State, using a structured questionnaire. The study revealed that most of the cassava marketers had secondary education (72.9%). The study also revealed that marketing of cassava is mostly undertaken by females (57%). The result showed that married people (59.8%) were mostly involved in the marketing of cassava. The s...

  2. Modelling potential β-carotene intake and cyanide exposure from consumption of biofortified cassava

    OpenAIRE

    Katz, Josh M.; Michael R La Frano; Winter, Carl K.; Burri, Betty J.

    2013-01-01

    Vitamin A (VA) deficiency causes disability and mortality. Cassava can be crossbred to improve its β-carotene (BC) content; typical white cassava contains negligible amounts of BC. However, cassava contains cyanide and its continued consumption may lead to chronic disability. Our objective was to estimate the risk–benefit of consuming BC-enhanced cassava to increase VA intake. A total of ten American women were fed white and BC-enhanced cassava. BC and cyanide data from the feeding study were...

  3. Expanding the Application of Cassava Value Chain Technologies Through UPoCA Project

    OpenAIRE

    Braima Dama James; P. Bramel; E. Witte; R. Asiedu; D. Watson; R. Okechuckwu.

    2013-01-01

    Cassava can play a key role in rural economic growth in Africa, but are we there yet? Cassava varieties with 50% more yielding potential and technologies to boost processing and marketing of cassava are available. However, the sub-sector is constrained by low productivity and marketing difficulties. In 2008, USAID and IITA initiated the project “Unleashing the Power of Cassava in Response to Food Price Crisis (UPOCA) as a multi-country and inter-institutional partnership enabling cassava sub-...

  4. CASSAVA (Manihot esculenta crantz): AN AFFORDABLE ENERGY SOURCE IN DAIRY RATIONS

    OpenAIRE

    F.R., ANJOS; L. TIVANA; J. DA CRUZ FRANCISCO; S. M. KAGANDE

    2014-01-01

    The current paper explores the evidence that exists on the potential use of cassava plant (Manihot esculenta Crantz) as an energy source for dairy cattle. Several studies have proven cassava roots, leaves and processing residues to be an important ruminant animal feed resource. Cassava root chip and meal are a potentially good rumen fermentable energy for dairy cows in the tropics. The vegetative parts of cassava are considered to be wastes since human beings grow cassava for its tubers. Feed...

  5. Modification of cell wall polysaccharides during retting of cassava roots.

    Science.gov (United States)

    Ngolong Ngea, Guillaume Legrand; Guillon, Fabienne; Essia Ngang, Jean Justin; Bonnin, Estelle; Bouchet, Brigitte; Saulnier, Luc

    2016-12-15

    Retting is an important step in traditional cassava processing that involves tissue softening of the roots to transform the cassava into flour and various food products. The tissue softening that occurs during retting was attributed to the degradation of cell wall pectins through the action of pectin-methylesterase and pectate-lyase that possibly originated from a microbial source or the cassava plant itself. Changes in cell wall composition were investigated during retting using chemical analysis, specific glycanase degradation and immuno-labelling of cell wall polysaccharides. Pectic 1,4-β-d-galactan was the main cell wall polysaccharide affected during the retting of cassava roots. This result suggested that better control of pectic galactan degradation and a better understanding of the degradation mechanism by endogenous endo-galactanase and/or exogenous microbial enzymes might contribute to improve the texture properties of cassava products. PMID:27451197

  6. Cassava Genetic Transformation and its Application in Breeding

    Institute of Scientific and Technical Information of China (English)

    Jia Liu; Qijie Zheng; Qiuxiang Ma; Kranthi Kumar Gadidasu; Peng Zhang

    2011-01-01

    As a major source of food, cassava (Manihot esculenta Crantz) is an important root crop in the tropics and subtropics of Africa and Latin America, and serves as raw material for the production of starches and bioethanol in tropical Asia. Cassava improvement through genetic engineering not only overcomes the high heterozygosity and serious trait separation that occurs in its traditional breeding, but also quickly achieves improved target traits. Since the first report on genetic transformation in cassava in 1996, the technology has gradually matured over almost 15 years of development and has overcome cassava genotype constraints, changing from mode cultivars to farmer-preferred ones.Significant progress has been made in terms of an increased resistance to pests and diseases, biofortification, and improved starch quality,building on the fundamental knowledge and technologies related to planting, nutrition, and the processing of this important food crop that has often been neglected. Therefore, cassava has great potential in food security and bioenergy development worldwide.

  7. Study on the Rheological Property of Cassava Starch Adhesives

    Directory of Open Access Journals (Sweden)

    Junjun Liu

    2014-03-01

    Full Text Available The main goal of this study was to use cassava starch in the production of environmentally sound adhesives. ‘Three-formaldehyde glue’ pollutes the environment and harms to human health strongly, which widely used for wood-based panels preparation. Environment-friendly cassava starch adhesives were prepared using method of oxidation-gelatinization, insteading of the three formaldehyde glue. The effects of the quality ratio of starch and water, temperature and shear rate on the apparent viscosity of the adhesive were studied. The rheological eigenvalue of apparent viscosity was studied through nonlinear regression. The results showed that the apparent viscosity of cassava starch adhesives decreased with the increasing of temperature; the apparent viscosity decreased slowly with the increasing of rotor speed; the phenomenon of shear thinning appeared within cassava starch adhesives which was pseudo-plastic fluids. Cassava starch adhesives with characteristics of non-toxic, no smell and pollution could be applied in interior and upscale packaging.

  8. Yellow cassava: efficacy of provitamin A rich cassava on improvement of vitamin A status in Kenyan schoolchildren

    NARCIS (Netherlands)

    Talsma, E.F.

    2014-01-01

    Background: Biofortified yellow cassava has great potential to alleviate vitamin A deficiency in sub-Saharan Africa and can be used as a complementary approach to other interventions. However, direct evidence whether yellow cassava can significantly contribute to the vitamin A intak

  9. Effect of cassava mosaic disease, soil fertility, plant spacing and their interactions on cassava yields in Zanzibar

    NARCIS (Netherlands)

    Spittel, M.C.; Huis, van A.

    2000-01-01

    Cassava Mosaic Disease (CMD) and low soil fertility are limiting factors for the production of the preferred cassava varWiety Kibiriti mwekundu on the northern part of the island of Pemba in Zanzibar. Because CMD severity, assessed 7 months after planting in shifting cultivation fields at wide spaci

  10. Unveiling the Micronome of Cassava (Manihot esculenta Crantz).

    Science.gov (United States)

    Rogans, Sarah Jane; Rey, Chrissie

    2016-01-01

    MicroRNAs (miRNAs) are an important class of endogenous non-coding single-stranded small RNAs (21-24 nt in length), which serve as post-transcriptional negative regulators of gene expression in plants. Despite the economic importance of Manihot esculenta Crantz (cassava) only 153 putative cassava miRNAs (from multiple germplasm) are available to date in miRBase (Version 21), and identification of a number of miRNAs from the cassava EST database have been limited to comparisons with Arabidopsis. In this study, mature sequences of all known plant miRNAs were used as a query for homologous searches against cassava EST and GSS databases, and additional identification of novel and conserved miRNAs were gleaned from next generation sequencing (NGS) of two cassava landraces (T200 from southern Africa and TME3 from West Africa) at three different stages post explant transplantation and acclimatization. EST and GSS derived data revealed 259 and 32 miRNAs in cassava, and one of the miRNA families (miR2118) from previous studies has not been reported in cassava. NGS data collectively displayed expression of 289 conserved miRNAs in leaf tissue, of which 230 had not been reported previously. Of the 289 conserved miRNAs identified in T200 and TME3, 208 were isomiRs. Thirty-nine novel cassava-specific miRNAs of low abundance, belonging to 29 families, were identified. Thirty-eight (98.6%) of the putative new miRNAs identified by NGS have not been previously reported in cassava. Several miRNA targets were identified in T200 and TME3, highlighting differential temporal miRNA expression between the two cassava landraces. This study contributes to the expanding knowledge base of the micronome of this important crop. PMID:26799216

  11. Unveiling the Micronome of Cassava (Manihot esculenta Crantz).

    Science.gov (United States)

    Rogans, Sarah Jane; Rey, Chrissie

    2016-01-01

    MicroRNAs (miRNAs) are an important class of endogenous non-coding single-stranded small RNAs (21-24 nt in length), which serve as post-transcriptional negative regulators of gene expression in plants. Despite the economic importance of Manihot esculenta Crantz (cassava) only 153 putative cassava miRNAs (from multiple germplasm) are available to date in miRBase (Version 21), and identification of a number of miRNAs from the cassava EST database have been limited to comparisons with Arabidopsis. In this study, mature sequences of all known plant miRNAs were used as a query for homologous searches against cassava EST and GSS databases, and additional identification of novel and conserved miRNAs were gleaned from next generation sequencing (NGS) of two cassava landraces (T200 from southern Africa and TME3 from West Africa) at three different stages post explant transplantation and acclimatization. EST and GSS derived data revealed 259 and 32 miRNAs in cassava, and one of the miRNA families (miR2118) from previous studies has not been reported in cassava. NGS data collectively displayed expression of 289 conserved miRNAs in leaf tissue, of which 230 had not been reported previously. Of the 289 conserved miRNAs identified in T200 and TME3, 208 were isomiRs. Thirty-nine novel cassava-specific miRNAs of low abundance, belonging to 29 families, were identified. Thirty-eight (98.6%) of the putative new miRNAs identified by NGS have not been previously reported in cassava. Several miRNA targets were identified in T200 and TME3, highlighting differential temporal miRNA expression between the two cassava landraces. This study contributes to the expanding knowledge base of the micronome of this important crop.

  12. Identification of Cassava MicroRNAs under Abiotic Stress.

    Science.gov (United States)

    Ballén-Taborda, Carolina; Plata, Germán; Ayling, Sarah; Rodríguez-Zapata, Fausto; Becerra Lopez-Lavalle, Luis Augusto; Duitama, Jorge; Tohme, Joe

    2013-01-01

    The study of microRNAs (miRNAs) in plants has gained significant attention in recent years due to their regulatory role during development and in response to biotic and abiotic stresses. Although cassava (Manihot esculenta Crantz) is tolerant to drought and other adverse conditions, most cassava miRNAs have been predicted using bioinformatics alone or through sequencing of plants challenged by biotic stress. Here, we use high-throughput sequencing and different bioinformatics methods to identify potential cassava miRNAs expressed in different tissues subject to heat and drought conditions. We identified 60 miRNAs conserved in other plant species and 821 potential cassava-specific miRNAs. We also predicted 134 and 1002 potential target genes for these two sets of sequences. Using real time PCR, we verified the condition-specific expression of 5 cassava small RNAs relative to a non-stress control. We also found, using publicly available expression data, a significantly lower expression of the predicted target genes of conserved and nonconserved miRNAs under drought stress compared to other cassava genes. Gene Ontology enrichment analysis along with condition specific expression of predicted miRNA targets, allowed us to identify several interesting miRNAs which may play a role in stress-induced posttranscriptional regulation in cassava and other plants. PMID:24328029

  13. An EST resource for cassava and other species of Euphorbiaceae.

    Science.gov (United States)

    Anderson, James V; Delseny, Michel; Fregene, Martin A; Jorge, Veronique; Mba, Chikelu; Lopez, Camilo; Restrepo, Silvia; Soto, Mauricio; Piegu, Benoit; Verdier, Valerie; Cooke, Richard; Tohme, Joe; Horvath, David P

    2004-11-01

    Cassava (Manihot esculenta) is a major food staple for nearly 600 million people in Africa, Asia, and Latin America. Major losses in yield result from biotic and abiotic stresses that include diseases such as Cassava Mosaic Disease (CMD) and Cassava Bacterial Blight (CBB), drought, and acid soils. Additional losses also occur from deterioration during the post-harvest storage of roots. To help cassava breeders overcome these obstacles, the scientific community has turned to modern genomics approaches to identify key genetic characteristics associated with resistance to these yield-limiting factors. One approach for developing a genomics program requires the development of ESTs (expressed sequence tags). To date, nearly 23,000 ESTs have been developed from various cassava tissues, and genotypes. Preliminary analysis indicates existing EST resources contain at least 6000-7000 unigenes. Data presented in this report indicate that the cassava ESTs will be a valuable resource for the study of genetic diversity, stress resistance, and growth and development, not only in cassava, but also other members of the Euphorbiaceae family. PMID:15630617

  14. Vertical Differentiation of Cassava Marketing Channels in Africa

    Directory of Open Access Journals (Sweden)

    Enete, AA.

    2008-01-01

    Full Text Available Farming systems in sub-Saharan Africa are inherently risky because they are fundamentally dependent on vagaries of weather. Sub-Saharan Africa is also a region in crises; poverty, civil strife and HIV/AIDS. Attention must therefore be focused on improving the production and marketing of crops that could thrive under these circumstances. Because of its tolerance of extreme drought and low input use conditions, Cassava is perhaps the best candidate in this regard. And cassava is a basic food staple and a major source of farm income for the people of the region. Efficiency in cassava marketing is a very important determinant of both consumers' living cost and producers' income in Africa. Vertical differentiation of marketing channels improves marketing efficiency. Identified in this paper are factors that drive vertical differentiation of cassava marketing channels. The paper is based on primary data collected within the framework of the Collaborative Study of Cassava in Africa. High population density, good market access conditions, availability of mechanized cassava processing technology and cassava price information stimulate vertical differentiation of the marketing channels.

  15. Melatonin attenuates postharvest physiological deterioration of cassava storage roots.

    Science.gov (United States)

    Ma, Qiuxiang; Zhang, Ting; Zhang, Peng; Wang, Zhen-Yu

    2016-05-01

    Melatonin reportedly increases abiotic and biotic stress tolerance in plants, but information on its in vivo effects during postharvest physiological deterioration (PPD) in cassava is limited. In this study, we investigated the effect of melatonin in regulating cassava PPD. Treatment with 500 mg/L melatonin significantly delayed cassava PPD and reduced the accumulation of hydrogen peroxide (H2 O2 ) while increasing the activity of superoxide dismutase (SOD), catalase (CAT), and glutathione reductase (GR), but not ascorbate peroxidase (APX). Transcript analysis further showed that expression of copper/zinc SOD (MeCu/ZnSOD), MeCAT1, glutathione peroxidase (MeGPX), peroxidase 3 (MePX3), and glutathione S-transferases (MeGST) was higher in cassava roots sliced treated with 500 mg/L melatonin than in those not exposed to exogenous melatonin. These data demonstrate that melatonin delays cassava PPD by directly or indirectly maintaining homoeostasis of cellular reactive oxygen species (ROS). We also found that accumulation of endogenous melatonin and the transcript levels of melatonin biosynthesis genes changed dynamically during the PPD process. This finding suggested that endogenous melatonin acts as a signal modulator for maintaining cassava PPD progression and that manipulation of melatonin biosynthesis genes through genetic engineering might prevent cassava root deterioration. PMID:26989849

  16. Identification of Cassava MicroRNAs under Abiotic Stress

    Directory of Open Access Journals (Sweden)

    Carolina Ballén-Taborda

    2013-01-01

    Full Text Available The study of microRNAs (miRNAs in plants has gained significant attention in recent years due to their regulatory role during development and in response to biotic and abiotic stresses. Although cassava (Manihot esculenta Crantz is tolerant to drought and other adverse conditions, most cassava miRNAs have been predicted using bioinformatics alone or through sequencing of plants challenged by biotic stress. Here, we use high-throughput sequencing and different bioinformatics methods to identify potential cassava miRNAs expressed in different tissues subject to heat and drought conditions. We identified 60 miRNAs conserved in other plant species and 821 potential cassava-specific miRNAs. We also predicted 134 and 1002 potential target genes for these two sets of sequences. Using real time PCR, we verified the condition-specific expression of 5 cassava small RNAs relative to a non-stress control. We also found, using publicly available expression data, a significantly lower expression of the predicted target genes of conserved and nonconserved miRNAs under drought stress compared to other cassava genes. Gene Ontology enrichment analysis along with condition specific expression of predicted miRNA targets, allowed us to identify several interesting miRNAs which may play a role in stress-induced posttranscriptional regulation in cassava and other plants.

  17. Middlemen and Smallholder Farmers in Cassava Marketing in Africa

    Directory of Open Access Journals (Sweden)

    Enete, AA.

    2009-01-01

    Full Text Available Cassava is a basic food staple and a major source of farm income in Africa. Efficiency in cassava marketing is therefore a very important determinant of consumers living cost and producers' income. Exploitation of one marketing agent by another in the course of product distribution could contribute to increased marketing costs and hence inefficiency. The paper examines the extent to which the widely held view that middlemen exploit farmers through monopsony purchases and usury apply to cassava farmers. The paper is based on primary data collected within the framework of the collaborative study of cassava in Africa (COSCA. The result of the analysis fails to support the view that middlemen generally engage in monopsony purchases of cassava products, because farmers had on average, higher volume of cassava products for sale in the market than middlemen. Prices of cassava products appeared more stable in Nigeria than in the other countries, because of the more elaborate involvement of middlemen, which encouraged competition. The intermediaries between the farmer and the consumer were at most three in each of the countries – the processor, the semi-wholesaler and the retailer. Cassava farmers and traders combined the role of the processor apparently because of the low development stage of mechanized processing technology. For both farmers and middlemen, transactions in cash were the predominant practice, followed by delayed payments. Advanced payment was non-existent except in Uganda. Marketing margins, though generally high, decline with good market access conditions. And the margins for granules were substantially lower than those of dried roots not only because of substantial differences in processing resource demand but also because of differences in marketing costs. This suggests that investments towards improving market access conditions, and in cost saving processing technologies for the production of granules are needed for the improvement

  18. Mathematical Modelling of Cassava Wastewater Treatment Using Anaerobic Baffled Reactor

    OpenAIRE

    A.O. Ibeje

    2013-01-01

    The performance of an anaerobic baffled reactor (ABR) was evaluated in the treatment of cassava wastewater as a pollutant residue. An ABR divided in four equal volume compartments (total volume 4L) and operated at 35°C was used in cassava wastewater treatment. Feed tank chemical oxygen demand (COD) was varied from 2000 to 7000mg L-1. The objective of the study was to formulate an improved mathematical model to describe cassava wastewater treatment without taking into account its inhibition ch...

  19. Utilization of cassava waste through fermentation technology

    International Nuclear Information System (INIS)

    Over 400 isolates of molds were screened for raw starch digesting enzymes and aspergillus J8 ad Rhizopus N37 were selected for further investigations. Crude enzymes obtained from wheat bran was higher than from rice bran. Crude enzymes from Aspergillus is active at pH 4.0, whereas that from Rhizopus is active at pH 5.0. Aspergillus J8 gave higher yield of silage fermentation. Selection of yeast strain was accomplished, it was found that Saccharomyces cerevisiae SC90, the local commercial strain (non-flocculent) performed best in fermentation of cassava mash. Another strain AM12, a flocculent fusant strain derived from fusion between flocculent strain and sake brewing strain was comparable to that of commercial strain at normal temperature but performed better at higher temperature up to 40 deg C. It is unlikely that fuel alcohol produced from raw cassava will be able to compete with petroleum fuel at this moment. However, silage fermentation to increase nutritional quality of the silage through selected strains of microorganisms has a good prospect to pursue. (author)

  20. CHARACTERISATION OF CASSAVA FIBRE FOR USE AS A BIOMATERIAL

    Directory of Open Access Journals (Sweden)

    Lois Larbie

    2012-07-01

    Full Text Available In this study we investigate the cytotoxicity of de-starched cassava fibre granules and fine powder using human peripheral blood mononuclear cells (PBMC and examine changes in the composition of Simulated Body Fluid (SBF resulting from immersion of cassava fibre samples. The purpose of the study was to characterise cassavafibre for possible biomaterial applications. Preliminary results indicate insignificant cytotoxic effects on PBMCs with cassava sample concentrations of 0.1g/ml, 0.025g/ml and 0.00625g/ml. Additionally there was little or no significant change in Na, K, Mg, Cl, Ca, Mn, and Cu concentrations upon immersion in SBF as observed over a one week period at a temperature of 37°C. These initial results suggest cassava fibre may be considered for biomaterial applications following more extensive characterisation.

  1. Mathematical Modelling Of Cyanide Inhibition on Cassava Wastewater Treatment

    OpenAIRE

    E. Onukwugha

    2013-01-01

    Anaerobic Baffled Reactors (ABR) is used to evaluate the extent of cyanide inhibition of cassava wastewater treatment. The reactor has aspect ratio of 4:1:1. Kinetic analyses of specific growth rate μmax and half saturation constant

  2. Physical properties of snacks made from cassava leaf flour

    Directory of Open Access Journals (Sweden)

    Adriana Cristina Ferrari

    2014-02-01

    Full Text Available The food industry is continually growing with new products becoming available every year. Extrusion combines a number of unit operations in one energy efficient rapid continuous process and can be used to produce a wide variety of snacks foods. The objective of this study was to evaluate the effect of extrusion temperature, screw speed, and amount of cassava leaf flour mixed with cassava starch on the physical properties of extruded snacks processed using a single screw extruder. A central composite rotational design, including three factors with 20 treatments, was used in the experimental design. Dependent variables included the expansion index, specific volume, color, water absorption index, and water solubility index. Among the parameters examined, the amount of cassava leaf flour and extrusion temperature showed significant effects on extruded snack characteristics. Mixtures containing 10% of cassava leaf flour extruded at 100°C and 255 rpm shows favorable levels of expansion, color, water absorption index, and water solubility index.

  3. Properties of baked foams from citric acid modified cassava starch and native cassava starch blends.

    Science.gov (United States)

    Pornsuksomboon, Kanlaya; Holló, Berta Barta; Szécsényi, Katalin Mészáros; Kaewtatip, Kaewta

    2016-01-20

    Starch foams from native cassava starch (NS) and citric acid modified cassava starch (CNS) were prepared using baking processes with blend ratios of 80/20, 60/40, 50/50, 40/60 and 20/80. The density, thickness, morphology, thermal stability and water absorption of the NS, CNS and blended starch foams were determined. The ratio of the two starch components had a significant influence on the density and thickness of the blended starch foams. All blended starch foams showed good water resistance. Moreover, the morphology of the blended starch foam with the NS/CNS ratio of 50/50 showed a more ordered distribution of cell sizes with thicker cell walls than for the NS and CNS foams. The thermal stability of the blended starch foams was somewhat lower than the stability of the NS foam but not to the extent that it affected any potential practical applications.

  4. Properties of baked foams from citric acid modified cassava starch and native cassava starch blends.

    Science.gov (United States)

    Pornsuksomboon, Kanlaya; Holló, Berta Barta; Szécsényi, Katalin Mészáros; Kaewtatip, Kaewta

    2016-01-20

    Starch foams from native cassava starch (NS) and citric acid modified cassava starch (CNS) were prepared using baking processes with blend ratios of 80/20, 60/40, 50/50, 40/60 and 20/80. The density, thickness, morphology, thermal stability and water absorption of the NS, CNS and blended starch foams were determined. The ratio of the two starch components had a significant influence on the density and thickness of the blended starch foams. All blended starch foams showed good water resistance. Moreover, the morphology of the blended starch foam with the NS/CNS ratio of 50/50 showed a more ordered distribution of cell sizes with thicker cell walls than for the NS and CNS foams. The thermal stability of the blended starch foams was somewhat lower than the stability of the NS foam but not to the extent that it affected any potential practical applications. PMID:26572335

  5. Sustainable Process Design of Biofuels: Bioethanol Production from Cassava rhizome

    OpenAIRE

    Mangnimit, S.; Malakul, P.; Gani, Rafiqul

    2013-01-01

    This study is focused on the sustainable process design of bioethanol production from cassava rhizome. The study includes: process simulation, sustainability analysis, economic evaluation and life cycle assessment (LCA). A steady state process simulation if performed to generate a base case design of the bioethanol conversion process using cassava rhizome as a feedstock. The sustainability analysis is performed to analyze the relevant indicators in sustainability metrics, todefinedesign/retro...

  6. Cassava crop improvement through in vitro mutation techniques

    International Nuclear Information System (INIS)

    Cassava is of great economic significance in Zambia due to its increasing role as a food security crop in drought prone areas of the country.Studies to improve the quality of the cassava tuber and the quality and quantity of the planting material using in vitro techniques is being conducted in several areas of Zambia. The preliminary results are encouraging from the field trials conducted so far

  7. Biogas Production From Cassava Starch Effluent Using Microalgae As Biostabilisator

    OpenAIRE

    B. Budiyono; Tutuk Djoko Kusworo

    2011-01-01

    The rapid growing of Indonesian population is emerging several critical national issues i.e. energy, food, environmental, water, transportation, as well as law and human right. As an agricultural country, Indonesia has abundant of biomass wastes such as agricultural wastes include the cassava starch wastes. The problem is that the effluent from cassava starch factories is released directly into the river before properly treatment. It has been a great source of pollution and has caused environ...

  8. Local domestication of lactic acid bacteria via cassava beer fermentation

    OpenAIRE

    Colehour, Alese M.; Meadow, James F.; Liebert, Melissa A.; Tara J. Cepon-Robins; Theresa E. Gildner; Urlacher, Samuel S.; Bohannan, Brendan J.M.; Snodgrass, J. Josh; Lawrence S. Sugiyama

    2014-01-01

    Cassava beer, or chicha, is typically consumed daily by the indigenous Shuar people of the Ecuadorian Amazon. This traditional beverage made from cassava tuber (Manihot esculenta) is thought to improve nutritional quality and flavor while extending shelf life in a tropical climate. Bacteria responsible for chicha fermentation could be a source of microbes for the human microbiome, but little is known regarding the microbiology of chicha. We investigated bacterial community composition of chic...

  9. The Symptom and Genetic Diversity of Cassava Brown Streak Viruses Infecting Cassava in East Africa

    Directory of Open Access Journals (Sweden)

    I. U. Mohammed

    2012-01-01

    Full Text Available The genetic and symptom diversity of six virus isolates causing cassava brown streak disease (CBSD in the endemic (Kenya, Mozambique, and Tanzania and the recently affected epidemic areas (Uganda of eastern Africa was studied. Five cassava varieties; Albert, Colombian, Ebwanateraka, TMS60444 (all susceptible and Kiroba (tolerant were graft inoculated with each isolate. Based on a number of parameters including the severity of leaf and root symptoms, and the extent of virus transmission by grafting, the viruses were classified as either severe or relatively mild. These results were further confirmed by the mechanical inoculation of 13 herbaceous hosts in which the virulent isolates caused plant death in Nicotiana clevelandii and N. benthamiana whereas the milder isolates did not. Phylogenetic analysis of complete coat protein gene sequences of these isolates together with sequences obtained from 14 other field-collected samples from Kenya and Zanzibar, and reference sequences grouped them into two distinct clusters, representing the two species of cassava brown streak viruses. Put together, these results did not suggest the association of a hypervirulent form of the virus with the current CBSD epidemic in Uganda. Identification of the severe and milder isolates, however, has further implications for disease management and quarantine requirements.

  10. A unigene catalogue of 5700 expressed genes in cassava.

    Science.gov (United States)

    Lopez, Camilo; Jorge, Véronique; Piégu, Benoît; Mba, Chickelu; Cortes, Diego; Restrepo, Silvia; Soto, Mauricio; Laudié, Michèle; Berger, Christel; Cooke, Richard; Delseny, Michel; Tohme, Joe; Verdier, Valérie

    2004-11-01

    Two economically important characters, starch content and cassava bacterial blight resistance, were targeted to generate a large collection of cassava ESTs. Two libraries were constructed from cassava root tissues of varieties with high and low starch contents. Other libraries were constructed from plant tissues challenged by the pathogen Xanthomonas axonopodis pv.manihotis. We report here the single pass sequencing of 11,954 cDNA clones from the 5' ends, including 111 from the 3' ends. Cluster analysis permitted the identification of a unigene set of 5,700 sequences. Sequence analyses permitted the assignment of a putative functional category for 37% of sequences whereas approximately 16% sequences did not show any significant similarity with other proteins present in the database and therefore can be considered as cassava specific genes. A group of genes belonging to a large multigene family was identified. We characterize a set of genes detected only in infected libraries putatively involved in the defense response to pathogen infection. By comparing two libraries obtained from cultivars contrasting in their starch content a group of genes associated to starch biosynthesis and differentially expressed was identified. This is the first large cassava EST resource developed today and publicly available thus making a significant contribution to genomic knowledge of cassava. PMID:15630618

  11. Cassava root membrane proteome reveals activities during storage root maturation.

    Science.gov (United States)

    Naconsie, Maliwan; Lertpanyasampatha, Manassawe; Viboonjun, Unchera; Netrphan, Supatcharee; Kuwano, Masayoshi; Ogasawara, Naotake; Narangajavana, Jarunya

    2016-01-01

    Cassava (Manihot esculenta Crantz) is one of the most important crops of Thailand. Its storage roots are used as food, feed, starch production, and be the important source for biofuel and biodegradable plastic production. Despite the importance of cassava storage roots, little is known about the mechanisms involved in their formation. This present study has focused on comparison of the expression profiles of cassava root proteome at various developmental stages using two-dimensional gel electrophoresis and LC-MS/MS. Based on an anatomical study using Toluidine Blue, the secondary growth was confirmed to be essential during the development of cassava storage root. To investigate biochemical processes occurring during storage root maturation, soluble and membrane proteins were isolated from storage roots harvested from 3-, 6-, 9-, and 12-month-old cassava plants. The proteins with differential expression pattern were analysed and identified to be associated with 8 functional groups: protein folding and degradation, energy, metabolism, secondary metabolism, stress response, transport facilitation, cytoskeleton, and unclassified function. The expression profiling of membrane proteins revealed the proteins involved in protein folding and degradation, energy, and cell structure were highly expressed during early stages of development. Integration of these data along with the information available in genome and transcriptome databases is critical to expand knowledge obtained solely from the field of proteomics. Possible role of identified proteins were discussed in relation with the activities during storage root maturation in cassava.

  12. Corrosion of Steels in Steel Reinforced Concrete in Cassava Juice

    Science.gov (United States)

    Oluwadare, G. O.; Agbaje, O.

    The corrosion of two types of construction steels, ST60Mn and RST37-2♦, in a low cyanide concentration environment (cassava juice) and embedded in concrete had been studied. The ST60 Mn was found to be more corrosion resistant in both ordinary water and the cassava juice environment. The cyanide in cassava juice does not attack the steel but it provides an environment of lower pH around the steel in the concrete which leads to breakdown of the passivating film provided by hydroxyl ions from cement. Other factors such as the curing time of the concrete also affect the corrosion rates of the steel in the concrete. The corrosion rate of the steel directly exposed to cassava juice i.e., steel not embedded in concrete is about twice that in concrete. Long exposure of concrete structure to cassava processing effluent might result in deterioration of such structures. Careful attention should therefore be paid to disposal of cassava processing effluents, especially in a country like Nigeria where such processing is now on the increase.

  13. Microbial population, chemical composition and silage fermentation of cassava residues.

    Science.gov (United States)

    Napasirth, Viengsakoun; Napasirth, Pattaya; Sulinthone, Tue; Phommachanh, Kham; Cai, Yimin

    2015-09-01

    In order to effectively use the cassava (Manihot esculenta Crantz) residues, including cassava leaves, peel and pulp for livestock diets, the chemical and microbiological composition, silage preparation and the effects of lactic acid bacteria (LAB) inoculants on silage fermentation of cassava residues were studied. These residues contained 10(4) to 10(5) LAB and yeasts, 10(3) to 10(4) coliform bacteria and 10(4) aerobic bacteria in colony forming units (cfu) on a fresh matter (FM) basis. The molds were consistently at or below the detectable level (10(2) cfu of FM) in three kinds of cassava residues. Dry matter (DM), crude protein (CP) and neutral detergent fiber (NDF) content of cassava residues were 17.50-30.95%, 1.30-16.41% and 25.40-52.90% on a DM basis, respectively. The silage treatments were designed as control silage without additive (CO) or with LAB inoculants Chikuso-1 (CH, Lactobacillus plantarum) and Snow Lacto (SN, Lactobacillus rhamnosus) at a rate of 5 mg/kg of FM basis. All silages were well preserved with a low pH (below 4.0) value and when cassava residues silage treated with inoculants CH and SN improved fermentation quality with a lower pH, butyric acid and higher lactic acid than control silage.

  14. Beauveria bassiana and Metarhizium anisopliae endophytically colonize cassava roots following soil drench inoculation

    Science.gov (United States)

    The fungal entomopathogens Beauveria bassiana and Metarhizium anisopliae were investigated to determine if endophytic colonization could be achieved in cassava. An inoculation method based on drenching the soil around cassava stems using conidial suspensions resulted in endophytic colonization of ca...

  15. Comparison of three cyanogen assays for total cyanogens in cassava (Manihot esculenta Crantz)

    DEFF Research Database (Denmark)

    Saka, J.D.K.; Mhone, A.R.K.; Brimer, Leon

    1997-01-01

    The sensitivity and reproducibility of three methods for determining the total cyanogenic potential (CNp) of 7 fresh and processed cassava varieties were determined and compared. The total cyanogen content of fresh cassava roots and three cassava products (kondowole, makaka, and starch) were...... analysed by the acid hydrolysis, microdiffusion with solid state detection and Cooke's enzymatic assays. The total cyanogen contents of the cassava, obtained by the three methods were not significantly different (p

  16. Exploring the potential of cassava in promoting agricultural growth in Nigeria

    OpenAIRE

    Sanzidur Rahman; Brodrick O. Awerije

    2016-01-01

    Cassava is one of the major food crops in Nigeria, with multiple uses from human consumption to industrial applications. This study explores the potential of cassava in Nigerian agriculture based on a review of cassava development policies; performs a trend analysis of the cultivation area, production, productivity, and real price of cassava and other competing crops for the period 1961–2013; identifies the sources of growth in production; and examines the production constraints at the local ...

  17. Yield and Properties of Ethanol Biofuel Produced from Different Whole Cassava Flours

    OpenAIRE

    Ademiluyi, F. T.; Mepba, H. D.

    2013-01-01

    The yield and properties of ethanol biofuel produced from five different whole cassava flours were investigated. Ethanol was produced from five different whole cassava flours. The effect of quantity of yeast on ethanol yield, effect of whole cassava flour to acid and mineralized media ratio on the yield of ethanol produced, and the physical properties of ethanol produced from different cassava were investigated. Physical properties such as distillation range, density, viscosity, and flash poi...

  18. EFFECT OF PROCESSING ON THE CYANIDE CONTENT OF CASSAVA PRODUCTS IN FIJI

    OpenAIRE

    Chand Bandna

    2012-01-01

    In Fiji cassava (Manihot esculenta Crantz, Euphorbiaceae) is one of the most important root crops. According to the 2004 National Nutrition Survey, 59.2% of the Fijian population consumes cassava on a daily basis while 31% of the Indian population consumes cassava on a weekly basis. Substantial quantity of anti-nutrient factor cyanogenic glucoside, linamarine and a small amount of lotaustralin is also present in cassava that interferes with digestion and uptake of nutrients. This study was ai...

  19. Cost benefit analysis of cassava production in Sherpur district of Bangladesh

    OpenAIRE

    Afreen, N.; Haque, M.S.

    2014-01-01

    The present study was designed to analyze the cost, benefit and profitability of cassava production in selected areas of Sherpur district in Bangladesh. Data were collected by interviewing a representative sample of 100 practicing cassava farmers, taking each 50 sample from traditional farmers of Jhinaigati and commercial cassava farmers of Sreebardi Upazila. Analyses showed that per hectare cost incurred for cassava was BDT 41,417.22 in Jhinaigati whereas BDT 53,642.59 in Sreebardi Upazila. ...

  20. Correlation of Chemical Compositions of Cassava Varieties to Their Resistance to Prostephanus truncatus Horn (Coleoptera: Bostrichidae)

    OpenAIRE

    Osipitan, Adebola A.; Sangowusi, Victoria T.; Lawal, Omoniyi I.; Popoola, Kehinde O.

    2015-01-01

    The preference of cassava as a major host by Prostephanus truncatus Horn is a major constraint to ample production of cassava, Manihot esculenta Crantz and storage. This study analyzed the nutritional and secondary metabolite compositions in 15 cassava varieties, evaluated levels of damage and reproduction by P. truncatus, and assessed their resistance to attack. One hundred grams of dried cassava chips in 250-ml Kilner jars were infested with 10 adult larger grain borerof 0–10 days old and h...

  1. PROCESSORS’ PERCEPTION OF THE EFFECTIVENESS OF SOME CASSAVA PROCESSING INNOVATIONS IN OGUN STATE, NIGERIA

    OpenAIRE

    Adebayo, K.; Sangosina, M.A.

    2005-01-01

    The current drive towards higher levels of commercialisation of cassava processing under the Presidential Initiative on Cassava requires that the scale of cassava processing be increased in Nigeria. Primary data obtained from 112 respondents selected from the 4 extension zones of Ogun State was used to examine the perception of effectiveness of innovations by cassava processors and the factors responsible for adoption of these innovations. The processors’ perception of effectiveness of cassav...

  2. Robust transformation procedure for the production of transgenic farmer-preferred cassava landraces

    OpenAIRE

    Zainuddin Ima M; Schlegel Kim; Gruissem Wilhelm; Vanderschuren Hervé

    2012-01-01

    Abstract Recent progress in cassava transformation has allowed the robust production of transgenic cassava even under suboptimal plant tissue culture conditions. The transformation protocol has so far been used mostly for the cassava model cultivar 60444 because of its good regeneration capacity of embryogenic tissues. However, for deployment and adoption of transgenic cassava in the field it is important to develop robust transformation methods for farmer- and industry-preferred landraces an...

  3. Distribution, incidence and abundance of the cassava brown root scale insect, Stictococcus vayssierei, in Cameroon

    NARCIS (Netherlands)

    Tchuanyo, M.; Huis, van A.; Lenteren, van J.C.

    2000-01-01

    A new scale insect, Stictococcus vayssierei, has been found attacking all the underground parts of cassava. From surveys in all the cassava-growing areas of Cameroon, the insect seems to be limited to the southern part of the country, where it is a major pest of cassava. This is the semi-humid zone

  4. Developing GM super cassava for improved health and food security: future challenges in Africa

    Directory of Open Access Journals (Sweden)

    Adenle Ademola A

    2012-08-01

    Full Text Available Abstract Background There is an urgent need to solve the problem of micronutrient malnutrition that is prevalent among young children and women in Africa. Genetically modified (GM biofortified cassava has great potential to solve part of this problem, but controversy surrounding GM technology and lack of awareness, limited facilities, biased news and other factors may hinder the adoption of GM cassava in the future. Method Using semi-structured interviews in Ghana and Nigeria, this paper examines the perspectives of scientists, including the BioCassava Plus (BC+ team, on the potential adoption of GM cassava for improving health and food security in Africa. The article also examines issues around the regulatory system and transfer and acceptance of GM cassava among scientists. Results and discussion The result suggests that an overwhelming majority of scientists agree that GM biofortified cassava will benefit the health of millions in Africa, and that GM cassava conferred with disease and pest resistance will increase cassava production as it is currently plagued by cassava mosaic diseases (CMD. However, respondents are wary of long-term effects of GM cassava on the environment and lack of a regulatory framework to facilitate the adoption of GM cassava. Even though scientists expressed little or no concern about health risks of GM cassava, they were concerned that consumers may express such concerns given limited understanding of GM technology. Conclusion The article concludes with a summary of priorities for policy development with regard to adopting biofortified food products.

  5. Diversity in oil content and fatty acid profile in seeds of wild cassava germplasm

    Science.gov (United States)

    Cassava (Manihot esculenta) is the only commercial species of the Manihot genus, cultivated for its starchy tuber roots. However, cassava seeds are known to be rich in oils and fats, there are scant reports on the content and properties of oil from cassava seeds and its wild relatives. Wild Manihot ...

  6. PHYTOPHARMACOLOGICAL ASPECTS OF MANIHOT ESCULENTA CRANTZ (CASSAVA

    Directory of Open Access Journals (Sweden)

    Bahekar S

    2013-01-01

    Full Text Available The plant kingdom has been the best source of remedies for curing a variety of diseases since ancient times. Plants continue to serve as possible sources for new drugs and chemicals derived from various parts of plants. Manihot esculenta Crantz, popularly known as cassava is one of the most neglected medicinal herbs found all over the world. It is not so commonly used in herbal medicine because of some of its potentially toxic components, but still various literatures have mentioned that this plant has numerous medicinal indications. Generally roots and leaves of this plant have been used in various parts of world for dietary as well as medicinal purposes. Though neglected, this is one of the most useful medicinal plants. In this review, we have tried to highlight various phytochemicals found and medicinal uses of this neglected plant.

  7. Slow Pyrolysis of Cassava Wastes for Biochar Production and Characterization

    Directory of Open Access Journals (Sweden)

    Nurhidayah Mohamed Noor

    2012-01-01

    Full Text Available Production of biochar from slow pyrolysis of biomass is a promising carbon negative procedure since it removes the net carbon dioxide in the atmosphere and produce recalcitrant carbon suitable for sequestration in soil. Biochar production can vary significantly with the pyrolysis parameter. This study investigated the impact of temperature and heating rate on the yield and properties of biochar derived from cassava plantations residues which are cassava stem (CS and cassava rhizome (CR. The pyrolysis temperatures ranged from 400°C to 600°C while the heating rate parameter was varied from 5°C/min to 25°C/min. The experiment was conducted using the lab scale slow pyrolysis system. The increment of temperature and heating rate of slow pyrolysis for both cassava wastes had raised the fixed carbon content of the biochar but decreased the biochar yield. More biochar was produced at lower temperature and lower heating rate. Temperature gave more influence on the biochar yield as compared to the heating rate parameter. The highest biochar yield of more than 35 mf wt. % can be obtained from both CS and CR at 400°C and heating rate of 5°C/min. From the proximate analysis, the results showed that cassava wastes contain high percentage of volatile matter which is more than 80 mf wt. %. Meanwhile, the biochar produced from cassava wastes contain high percentage of fixed carbon which is about 5−8 times higher than their raw samples. This suggested that, it is a good step to convert CS and CR into high carbon biochar via slow pyrolysis process that can substantially yield more biochar, up to 37 mf wt. % in this study. Since the fixed carbon content for both CS and CR biochar produced in any studied parameter were found to be more than 75 mf wt. %, it is suggested that biochar from cassava wastes is suitable for carbon sequestration.

  8. Characterization of Brown Streak Virus-Resistant Cassava.

    Science.gov (United States)

    Anjanappa, Ravi B; Mehta, Devang; Maruthi, M N; Kanju, Edward; Gruissem, Wilhelm; Vanderschuren, Hervé

    2016-07-01

    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. PMID:27070326

  9. Characterization of Brown Streak Virus-Resistant Cassava.

    Science.gov (United States)

    Anjanappa, Ravi B; Mehta, Devang; Maruthi, M N; Kanju, Edward; Gruissem, Wilhelm; Vanderschuren, Hervé

    2016-07-01

    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.

  10. Engineering cyanogen synthesis and turnover in cassava (Manihot esculenta).

    Science.gov (United States)

    Siritunga, Dimuth; Sayre, Richard

    2004-11-01

    Cassava is the major root crop for a quarter billion subsistence farmers in sub-Saharan Africa. It is valued for its ability to grow in adverse environments and the food security it provides. Cassava contains potentially toxic levels of cyanogenic glycosides (linamarin) which protect the plant from herbivory and theft. The cyanogens, including linamarin and its deglycosylated product, acetone cyanohydrin, can be efficiently removed from the root by various processing procedures. Short-cuts in processing, which may occur during famines, can result in only partial removal of cyanogens. Residual cyanogens in cassava foods may cause neurological disorders or paralysis, particularly in nutritionally compromised individuals. To address this problem and to further understand the function of cyanogenic glycosides in cassava, we have generated transgenic cassava in which cyanogenic glycoside synthesis has been selectively inhibited in leaves and roots by antisense expression of CYP79D1/D2 gene fragments. The CYP79D1/D2 genes encode two highly similar cytochrome P450s that catalyze the first-dedicated step in cyanogenic glycoside synthesis. Transgenic plants in which the expression of these genes was selectively inhibited in leaves had substantially reduced (60- 94% reduction) linamarin leaf levels. Surprisingly, these plants also had a greater than a 99% reduction in root linamarin content. In contrast, transgenic plants in which the CYP79D1/D2 transcripts were reduced to non-detectable levels in roots had normal root linamarin levels. These results demonstrate that linamarin synthesized in leaves is transported to the roots and accounts for nearly all of the root linamarin content. Importantly, transgenic plants having reduced leaf and root linamarin content were unable to grow in the absence of reduced nitrogen (NH3) . Cassava roots have previously been demonstrated to have an active cyanide assimilation pathway leading to the synthesis of amino acids. We propose that

  11. Cassava physiological responses to the application of herbicides

    Directory of Open Access Journals (Sweden)

    Evander Alves Ferreira

    2015-04-01

    Full Text Available Analysis of chlorophyll a fluorescence has been used to improve the understanding of the mechanisms of photosynthesis, as well as in the evaluation of plant photosynthetic capacity altered by biotic or abiotic stresses. The objective of this study was to evaluate the sensitivity of cassava plants to herbicides with different mechanisms of action, as well as the damage caused by the application of herbicides on the photosynthetic apparatus of these plants. An experiment was conducted in a randomized block design with four replications. The treatments were constituted of the application of the following post- emergence herbicides in cassava: bentazon, clomazone, fomesafen, fluazifop-p-buthyl, glyphosate, nicosulfuron, chlorimuron, fluazifop-p-buthyl + fomesafen, sulfentrazone, besides a control without application. The visual intoxication and chlorophyll a fluorescence assessments were performed at 2, 9, 16 and 23 days after herbicide application. The herbicides evaluated affected differently the cassava plants. Sulfentrazone and glyphosate promoted plant death. Herbicides clomazone, fomesafen, fluazifop-p-buthyl and chlorimuron-ehtyl caused low toxicity to cassava plants and did not affect the ratio Fv / Fm and ETR. However, for the mixture nicossulfuron and fluazifop-p-buthyl + fomesafen values of Fv / Fm were suboptimal in the first evaluation times but plants treated with these herbicides had recovered. Physiological evaluations can be used as a way to evaluate the selectivity of herbicides in cassava crop as presented similar answers to those observed for visual intoxication symptoms.

  12. Use of irradiation to extend shelf life of cassava tubers

    International Nuclear Information System (INIS)

    Fresh cassava tubers (manihot esculenta crantz) were gamma irradiated at 0, 0.2, 0.5 and 1.0 KGy doses using cobalt-60 source. A portion of the irradiated cassava tubers was stored at room temperature (25-30 degree C) and the rest was packed in polyethylene bags and stored in refrigerator (5 1 degree C). Samples were analyzed for moisture, crude protein, starch and fibers percentages. Rotting ratio and weight loss percentages were also determined. The results indicated that the irradiation with gamma-rays followed by refrigeration extended the shelf-life of cassava tubers being more than 21 days. The lowest value of weight loss of cassava tubers during storage was observed by gamma irradiation and cold storage. Moreover, the irradiation treatments had no effect on protein content of cassava tubers, while it decreased moisture, starch and fiber contents especially those subjected to 1 kGy. As for the interaction between gamma-irradiation doses and periods of storage the crude protein slightly increased while the moisture, starch and fibers showed a gradual decrease up to the end of storage period as compared to unirradiated ones. 4 tabs

  13. CASSAVA (Manihot esculenta crantz: AN AFFORDABLE ENERGY SOURCE IN DAIRY RATIONS

    Directory of Open Access Journals (Sweden)

    F.R., ANJOS

    2014-01-01

    Full Text Available The current paper explores the evidence that exists on the potential use of cassava plant (Manihot esculenta Crantz as an energy source for dairy cattle. Several studies have proven cassava roots, leaves and processing residues to be an important ruminant animal feed resource. Cassava root chip and meal are a potentially good rumen fermentable energy for dairy cows in the tropics. The vegetative parts of cassava are considered to be wastes since human beings grow cassava for its tubers. Feeding trials with cattle have shown cassava hay to have a dry matter intake levels DMI of around 3.2% of BW and a digestibility (71%. The hay also contains tannin-protein complexes that may be a good source of rumen un-degradable protein that will be available to the animal post-ruminally. It has also be shown that supplementing 1-2 kg/head/day of cassava to dairy cattle may go a long way in reducing feeding costs and significantly increasing milk quality and quantity produced. Cassava hay was also noted to be anthelminthic and therapeutic since it contains condensed tannins. Condensed tannins have been proven to reduce gastrointestinal nematodes. Use of cassava as a substitute of maize in dairy rations can significantly lower the feed costs in smallholder dairy farms in cassava producing countries like Mozambique. It was concluded that cassava is potentially an affordable substitute for conventional energy source for small scale dairy farmers.

  14. Expression of Cry1Aa in cassava improves its insect resistance against Helicoverpa armigera.

    Science.gov (United States)

    Duan, Xiaoguang; Xu, Jia; Ling, Erjun; Zhang, Peng

    2013-09-01

    Lepidopteran insects affect cassava production globally, especially in intercropping system. The expression of Cry toxins in transgenic crops has contributed to an efficient control of insect pests, leading to a significant reduction in chemical insecticide usage. Helicoverpa armigera is a Lepidopteran pest that feeds on a wide range of plants like cotton and cassava. In the present study, transgenic cassava plants over-expressing Cry1Aa, which we named as Bt cassava, were developed and used to evaluate its efficacy against H. armigera as a model. Insect feeding assays were carried out to test the effects of Bt cassava leaves on the development and survival of H. armigera. Significant reduction (P cassava leaves in comparison with those fed with wild-type cassava leaves. The higher expression of Cry1Aa in transgenic cassava caused the lethal effect in larvae, in contrast to the normal growth and development of adults and pupation observed when fed with wild-type leaves. Morphological observation on the larval midguts showed that the consumption of Bt cassava affected the gut integrity of H. armigera. The columnar cells of the midgut epithelium were dramatically damaged and showed loose or disordered structure. Their cytoplasms become highly vacuolated and contained disorganized microvilli. Our study demonstrated that the transgenic cassava expressing the Cry1Aa is effective in controlling H. armigera. Our Bt transgenic cassava plant would provide a long-term beneficial effect on all crops in intercropping system, which in-turn, will be profitable to the farmers.

  15. Promoting Cassava as an Industrial Crop in Ghana: Effects on Soil Fertility and Farming System Sustainability

    Directory of Open Access Journals (Sweden)

    S. Adjei-Nsiah

    2012-01-01

    Full Text Available Cassava is an important starchy staple crop in Ghana with per capita consumption of 152.9 kg/year. Besides being a staple food crop, cassava can be used as raw material for the production of industrial starch and ethanol. The potential of cassava as an industrial commercial crop has not been exploited to a large extent because of perceptions that cassava depletes soils. Recent finding from field studies in the forest/savannah transitional agroecological zone of Ghana indicates that when integrated in the cropping system as a form of rotation, cassava contributes significantly to maintenance of soil fertility, and thus large scale production of cassava for industrial use can contribute to poverty reduction in an environmentally responsive way. This paper discusses the role of cassava cultivation in soil fertility management and its implication for farming system sustainability and industrialization.

  16. Cassava for food and energy: exploring potential benefits of processing of cassava into cassava flour and bioenergy at farmstead and community levels in rural Mozambique

    NARCIS (Netherlands)

    Zvinavashe, E.; Elbersen, H.W.; Slingerland, M.A.; Kolijn, S.; Sanders, J.P.M.

    2011-01-01

    As in most of sub-Sahara Africa, rural people in Mozambique use firewood as their main source of energy. The use of firewood is associated with several health problems, and the time spent collecting it reduces time for other activities. Cassava is grown as a reserve crop in Mozambique where it is co

  17. Quantification of African cassava mosaic virus (ACMV) and East African cassava mosaic virus (EACMV-UG) in single and mixed infected Cassava (Manihot esculenta Crantz) using quantitative PCR.

    Science.gov (United States)

    Naseem, Saadia; Winter, Stephan

    2016-01-01

    The quantity of genomic DNA-A and DNA-B of African cassava mosaic virus (ACMV) and East African cassava mosaic virus Uganda (Uganda variant, EACMV-UG) was analysed using quantitative PCR to assess virus concentrations in plants from susceptible and tolerant cultivars. The concentrations of genome components in absolute and relative quantification experiments in single and mixed viral infections were determined. Virus concentration was much higher in symptomatic leaf tissues compared to non-symptomatic leaves and corresponded with the severity of disease symptoms. In general, higher titres were recorded for EACMV-UG Ca055 compared to ACMV DRC6. The quantitative assessment also showed that the distribution of both viruses in the moderately resistant cassava cv. TMS 30572 was not different from the highly susceptible cv. TME 117. Natural mixed infections with both viruses gave severe disease symptoms. Relative quantification of virus genomes in mixed infections showed higher concentrations of EACMV-UG DNA-A compared to ACMV DNA-A, but a marked reduction of EACMV-UG DNA-B. The higher concentrations of EACMV-UG DNA-B compared to EACMV DNA-A accumulation in single infections were consistent. Since DNA-B is implicated in virus cell-to-cell spread and systemic movement, the abundance of the EACMV-UG DNA-B may be an important factor driving cassava mosaic disease epidemic.

  18. Linamarase production by some microbial isolates and a comparison of the rate of degradation of cassava cyanide by microbial and cassava linamarases

    Directory of Open Access Journals (Sweden)

    Ogbonnaya Nwokoro

    2016-01-01

    Full Text Available Production of linamarase and the effects of media composition on enzyme production were studied. A total of eight linamarase-producing bacteria were isolated from fermenting cassava tubers and soil samples. Selection of the isolates was based on their high growth in media containing 800 mg/L potassium cyanide solution. Eight of the isolates which showed very high growth in the growth medium as demonstrated by increase in their optical density readings to at least 0.6 in the cyanide containing media were selected for further studies. The isolates were identified as Lactobacillus plantarum, Lactobacillus fermentum, Lactobacillus amylovorus, Lactobacillus cellobiosus, Leuconostoc mesenteroides, Pseudomonas stutzeri, Bacillus pumilus and Bacillus subtilis. All the isolates were grown in media containing Tween 80 solution and in control media without the surfactant. Best enzyme activity of 6.82 U/mL was obtained in the medium containing Tween 80 solution and Lactobacillus fermentum as the test bacterium. Comparatively, linamarase production by the isolates in media without Tween 80 showed lower enzyme productivity. Cassava endogenous and microbial enzymes were tested for their abilities to hydrolyze cyanide in cassava flour samples pretreated to either remove the endogenous or microbial enzyme. Residual cyanide in cassava flour samples treated with linamarase of Lactobacillus plantarum was undecteded in 30 h, while in contrast, the residual cyanide in cassava flour samples treated with endogenous linamarase was 0.39 mg/10g cassava flour after 80 h. Residual cyanide in the untreated control sample was 1.98 mg HCN /10g cassava flour after 80 h. The results from this finding demonstrated improved cassava cyanide degradation with microbial linamarase as compared to endogenous cassava linamarase. Massive inoculation of fermenting cassava tubers with the isolates reported in this study would enable better control of the cassava fermentation process and may

  19. Molecular biodiversity of cassava begomoviruses in Tanzania: evolution of cassava geminiviruses in Africa and evidence for East Africa being a center of diversity of cassava geminiviruses

    Directory of Open Access Journals (Sweden)

    Aveling TAS

    2005-03-01

    Full Text Available Abstract Cassava is infected by numerous geminiviruses in Africa and India that cause devastating losses to poor farmers. We here describe the molecular diversity of seven representative cassava mosaic geminiviruses (CMGs infecting cassava from multiple locations in Tanzania. We report for the first time the presence of two isolates in East Africa: (EACMCV-[TZ1] and EACMCV-[TZ7] of the species East African cassava mosaic Cameroon virus, originally described in West Africa. The complete nucleotide sequence of EACMCV-[TZ1] DNA-A and DNA-B components shared a high overall sequence identity to EACMCV-[CM] components (92% and 84%. The EACMCV-[TZ1] and -[TZ7] genomic components have recombinations in the same genome regions reported in EACMCV-[CM], but they also have additional recombinations in both components. Evidence from sequence analysis suggests that the two strains have the same ancient origin and are not recent introductions. EACMCV-[TZ1] occurred widely in the southern part of the country. Four other CMG isolates were identified: two were close to the EACMV-Kenya strain (named EACMV-[KE/TZT] and EACMV-[KE/TZM] with 96% sequence identity; one isolate, TZ10, had 98% homology to EACMV-UG2Svr and was named EACMV-UG2 [TZ10]; and finally one isolate was 95% identical to EACMV-[TZ] and named EACMV-[TZ/YV]. One isolate of African cassava mosaic virus with 97% sequence identity with other isolates of ACMV was named ACMV-[TZ]. It represents the first ACMV isolate from Tanzania to be sequenced. The molecular variability of CMGs was also evaluated using partial B component nucleotide sequences of 13 EACMV isolates from Tanzania. Using the sequences of all CMGs currently available, we have shown the presence of a number of putative recombination fragments that are more prominent in all components of EACMV than in ACMV. This new knowledge about the molecular CMG diversity in East Africa, and in Tanzania in particular, has led us to hypothesize about the

  20. Transcriptional response of virus-infected cassava and identification of putative sources of resistance for cassava brown streak disease.

    Science.gov (United States)

    Maruthi, M N; Bouvaine, Sophie; Tufan, Hale A; Mohammed, Ibrahim U; Hillocks, Rory J

    2014-01-01

    Cassava (Manihot esculenta) is a major food staple in sub-Saharan Africa, which is severely affected by cassava brown streak disease (CBSD). The aim of this study was to identify resistance for CBSD as well as to understand the mechanism of putative resistance for providing effective control for the disease. Three cassava varieties; Kaleso, Kiroba and Albert were inoculated with cassava brown streak viruses by grafting and also using the natural insect vector the whitefly, Bemisia tabaci. Kaleso expressed mild or no disease symptoms and supported low concentrations of viruses, which is a characteristic of resistant plants. In comparison, Kiroba expressed severe leaf but milder root symptoms, while Albert was susceptible with severe symptoms both on leaves and roots. Real-time PCR was used to estimate virus concentrations in cassava varieties. Virus quantities were higher in Kiroba and Albert compared to Kaleso. The Illumina RNA-sequencing was used to further understand the genetic basis of resistance. More than 700 genes were uniquely overexpressed in Kaleso in response to virus infection compared to Albert. Surprisingly, none of them were similar to known resistant gene orthologs. Some of the overexpressed genes, however, belonged to the hormone signalling pathways and secondary metabolites, both of which are linked to plant resistance. These genes should be further characterised before confirming their role in resistance to CBSD.

  1. Analyses of Twelve New Whole Genome Sequences of Cassava Brown Streak Viruses and Ugandan Cassava Brown Streak Viruses from East Africa: Diversity, Supercomputing and Evidence for Further Speciation

    OpenAIRE

    Ndunguru, Joseph; Sseruwagi, Peter; Tairo, Fred; Stomeo, Francesca; Maina, Solomon; Djinkeng, Appolinaire; Kehoe, Monica; Boykin, Laura M

    2015-01-01

    Cassava brown streak disease is caused by two devastating viruses, Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV) which are frequently found infecting cassava, one of sub-Saharan Africa’s most important staple food crops. Each year these viruses cause losses of up to $100 million USD and can leave entire families without their primary food source, for an entire year. Twelve new whole genomes, including seven of CBSV and five of UCBSV were uncovered in this re...

  2. Transcriptional response to petiole heat girdling in cassava.

    Science.gov (United States)

    Zhang, Yang; Ding, Zehong; Ma, Fangfang; Chauhan, Raj Deepika; Allen, Doug K; Brutnell, Thomas P; Wang, Wenquan; Peng, Ming; Li, Pinghua

    2015-01-01

    To examine the interactions of starch and sugar metabolism on photosynthesis in cassava, a heat-girdling treatment was applied to petioles of cassava leaves at the end of the light cycle to inhibit starch remobilization during the night. The inhibition of starch remobilization caused significant starch accumulation at the beginning of the light cycle, inhibited photosynthesis, and affected intracellular sugar levels. RNA-seq analysis of heat-treated and control plants revealed significantly decreased expression of genes related to photosynthesis, as well as N-metabolism and chlorophyll biosynthesis. However, expression of genes encoding TCA cycle enzymes and mitochondria electron transport components, and flavonoid biosynthetic pathway enzymes were induced. These studies reveal a dynamic transcriptional response to perturbation of sink demand in a single leaf, and provide useful information for understanding the regulations of cassava under sink or source limitation.

  3. Sustainable Process Design of Biofuels: Bioethanol Production from Cassava rhizome

    DEFF Research Database (Denmark)

    Mangnimit, S.; Malakul, P.; Gani, Rafiqul

    2013-01-01

    This study is focused on the sustainable process design of bioethanol production from cassava rhizome. The study includes: process simulation, sustainability analysis, economic evaluation and life cycle assessment (LCA). A steady state process simulation if performed to generate a base case design...... of the bioethanol conversion process using cassava rhizome as a feedstock. The sustainability analysis is performed to analyze the relevant indicators in sustainability metrics, to definedesign/retrofit targets for process improvements. Economic analysis is performed to evaluate the profitability of the process...... in order to identify the most sustainable design for the production of ethanol. The capacity for ethanol production from cassava rhizome is set to 150,000 liters/day, which is about 1.3 % of the total demand of ethanol in Thailand. LCA on the base case design pointed to large amounts of CO2 and CO...

  4. Quality management manual for production of high quality cassava flour

    DEFF Research Database (Denmark)

    Dziedzoave, Nanam Tay; Abass, Adebayo Busura; Amoa-Awua, Wisdom K.;

    The high quality cassava flour (HQCF) industry has just started to evolve in Africa and elsewhere. The sustainability of the growing industry, the profitability of small- and medium-scale enterprises (SMEs) that are active in the industry and good-health of consumers can best be guaranteed through...... the adoption of proper quality and food safety procedures. Cassava processing enterprises involved in the productionof HQCF must therefore be commited to the quality and food safety of the HQCF. They must have the right technology, appropriate processing machhinery, standard testing instruments...... and the necessary technical expertise. This quality manual was therefore developed to guide small- to medium-scale cassava in the design and implematation of Hazard Analysis Critical Control Point (HACCP) system and Good manufacturing Practices (GMP) plans for HQCF production. It describes the HQCF production...

  5. Biogas Production From Cassava Starch Effluent Using Microalgae As Biostabilisator

    Directory of Open Access Journals (Sweden)

    B. Budiyono

    2011-07-01

    Full Text Available The rapid growing of Indonesian population is emerging several critical national issues i.e. energy, food, environmental, water, transportation, as well as law and human right. As an agricultural country, Indonesia has abundant of biomass wastes such as agricultural wastes include the cassava starch wastes. The problem is that the effluent from cassava starch factories is released directly into the river before properly treatment. It has been a great source of pollution and has caused environmental problems to the nearby rural population. The possible alternative to solve the problem is by converting waste to energy biogas in the biodigester. The main problem of the biogas production of cassava starch effluent is acid forming-bacteria quickly produced acid resulting significantly in declining pH below the neutral pH and diminishing growth of methane bacteria. Hence, the only one of the method to cover this problem is by adding microalgae as biostabilisator of pH. Microalgae can also be used as purifier agent to absorb CO2.The general objective of this research project was to develop an integrated process of biogas production and purification from cassava starch effluent by using biostabilisator agent microalgae. This study has been focused on the used of urea, ruminant, yeast, microalgae, the treatment of gelled and ungelled feed for biogas production, pH control during biogas production using buffer Na2CO3, and feeding management in the semi-continuous process of biogas production. The result can be concluded as follows: i The biogas production increased after cassava starch effluent and yeast was added, ii Biogas production with microalgae and cassava starch effluent, yeast, ruminant bacteria, and urea were 726.43 ml/g total solid, iii Biogas production without  microalgae was 189 ml/g total solid.

  6. Effect of protein supplemented cassava diet in rats.

    Science.gov (United States)

    Sreeja, V G; Leelamma, S

    1996-04-01

    The effect of feeding rats with cassava diet (tapioca) has been investigated with respect to the activities of superoxide dismutase, catalase and levels of TBARS. By varying the levels of protein in the diet and cyanide content of cassava, the possible role of a high protein diet in the prevention of oxidant stress has been shown. Rhodanese which detoxifes cyanide is also found to be inhibited in rats fed low protein diet while the inhibition was only marginal in the high protein fed groups. PMID:8754627

  7. Cassava leaves as protein source for pigs in Central Vietnam

    OpenAIRE

    2007-01-01

    The aim of the studies described in this thesis was to evaluate the use of cassava leaves as protein sources for pigs when used at high levels in the diet, either in fresh form or with simplified methods of processing. In twenty cassava varieties taken from the upper part of the plant at the root harvesting, the crude protein varied from 23.7 to 29.5 % in DM and the HCN from 610 to 1840 mg/kg DM. Chopping, washing and wilting the leaves are simple ways to process the. There was a 58% reductio...

  8. Anatomic changes due to interspecific grafting in cassava (Manihot esculenta).

    Science.gov (United States)

    Bomfim, N; Ribeiro, D G; Nassar, N M A

    2011-05-31

    Cassava rootstocks of varieties UnB 201 and UnB 122 grafted with scions of Manihot fortalezensis were prepared for anatomic study. The roots were cut, stained with safranin and alcian blue, and examined microscopically, comparing them with sections taken from ungrafted roots. There was a significant decrease in number of pericyclic fibers, vascular vessels and tyloses in rootstocks. They exhibited significant larger vessels. These changes in anatomic structure are a consequence of genetic effects caused by transference of genetic material from scion to rootstock. The same ungrafted species was compared. This is the first report on anatomic changes due to grafting in cassava.

  9. Life cycle cost of ethanol production from cassava in Thailand

    Energy Technology Data Exchange (ETDEWEB)

    Sorapipatana, Chumnong; Yoosin, Suthamma [Joint Graduate School of Energy and Environment, King Mongkut' s University of Technology Thonburi, Pracha-Uthit Rd., Tungkru, Bangmod, Bangkok 10140 (Thailand); Center for Energy Technology and Environment, Commission on Higher Education, Ministry of Education, Bangkok (Thailand)

    2011-02-15

    To increase the security of energy supply, lessen dependence on crude oil import and buffer against the impacts of large change in crude oil prices, the Thai government initiated and officially announced the national ethanol fuel program in year 2000. Since then, domestic ethanol demand has grown rapidly. Presently, all commercial ethanol in Thailand is produced from molasses as Thai law prohibits producing it from sugar cane directly. This is likely to limit ethanol supply in the near future. One possible solution is to supply more ethanol from cassava which is widely cultivated in this country. However, its production cost has not yet been known for certain. The objective of this study is to estimate the life cycle cost of ethanol production from cassava and to assess its economic competitiveness with gasoline in the Thai fuel market. Based on the record of cassava prices during the years 2002-2005, it was found that using it as feedstock would share more than 50% of the ethanol from cassava total production cost. It was also found that a bio-ethanol plant, with a capacity of 150,000 l/day, can produce ethanol from cassava in a range of ex-factory costs from 16.42 to 20.83 baht/l of gasoline equivalent (excluding all taxes), with an average cost of 18.15 baht/l of gasoline equivalent (41, 52 and 45 US cents/l gasoline equivalent respectively, based on 2005 exchange rate). In the same years, the range of 95-octane gasoline prices in Thailand varied from 6.18 baht to 20.86 baht/l, with an average price of 11.50 baht/l (15, 52 and 29 US cents/l respectively, based on 2005 exchange rate) which were much cheaper than the costs of ethanol made from cassava. Thus, we conclude that under the scenario of low to normal crude oil price, ethanol from cassava is not competitive with gasoline. The gasoline price has to rise consistently above 18.15 baht (45 US cents)/l before ethanol made from cassava can be commercially competitive with gasoline. (author)

  10. Life cycle cost of ethanol production from cassava in Thailand

    International Nuclear Information System (INIS)

    To increase the security of energy supply, lessen dependence on crude oil import and buffer against the impacts of large change in crude oil prices, the Thai government initiated and officially announced the national ethanol fuel program in year 2000. Since then, domestic ethanol demand has grown rapidly. Presently, all commercial ethanol in Thailand is produced from molasses as Thai law prohibits producing it from sugar cane directly. This is likely to limit ethanol supply in the near future. One possible solution is to supply more ethanol from cassava which is widely cultivated in this country. However, its production cost has not yet been known for certain. The objective of this study is to estimate the life cycle cost of ethanol production from cassava and to assess its economic competitiveness with gasoline in the Thai fuel market. Based on the record of cassava prices during the years 2002-2005, it was found that using it as feedstock would share more than 50% of the ethanol from cassava total production cost. It was also found that a bio-ethanol plant, with a capacity of 150,000 l/day, can produce ethanol from cassava in a range of ex-factory costs from 16.42 to 20.83 baht/l of gasoline equivalent (excluding all taxes), with an average cost of 18.15 baht/l of gasoline equivalent (41, 52 and 45 US cents/l gasoline equivalent respectively, based on 2005 exchange rate). In the same years, the range of 95-octane gasoline prices in Thailand varied from 6.18 baht to 20.86 baht/l, with an average price of 11.50 baht/l (15, 52 and 29 US cents/l respectively, based on 2005 exchange rate) which were much cheaper than the costs of ethanol made from cassava. Thus, we conclude that under the scenario of low to normal crude oil price, ethanol from cassava is not competitive with gasoline. The gasoline price has to rise consistently above 18.15 baht (45 US cents)/l before ethanol made from cassava can be commercially competitive with gasoline. (author)

  11. Radiation processing of cassava starch hydrogel

    International Nuclear Information System (INIS)

    This paper consists of two topics on cassava starch (CS). The first paper deals with radiation-induced graft polymerization of 1-vinyl-2-pyrrolidinone (VP) onto CS. The results from PVP -grafted-starch were subsequently compared with those of PVP hydrogels and PVP-blended-starch hydrogels. It was found that the PVP-grafted-starch hydrogels, with gel fraction higher than 80%, could be prepared at the dose of 20 kGy, while PVP and PVP-blended-starch hydrogels require at least 30 kGy to obtain gels with more than 80% gel fraction. And at the same dose used for irradiation, the gel strength of the PVP-grafted-starch hydrogels is significantly higher than that of the PVP and PVP-blended-starch hydrogels. Radiation crosslinking of carboxymethyl CS is the second topic. CS was chemically modified by sodium monochloroacetate (SMCA) to yield carboxymethyl starch (CMS). The aqueous solution of CMS was irradiated and underwent radiation-induced crosslinking, resulting in a crosslinked CMS (XLCMS) hydrogel. The optimum condition for obtaining hydrogels with desirable properties is irradiation at low dose, 2 kGy. At higher doses, the gel fraction tends to diminish, due to the domination of degradation over crosslinking. (author)

  12. Comparative analysis of virus-derived small RNAs within cassava (Manihot esculenta Crantz) infected with cassava brown streak viruses.

    Science.gov (United States)

    Ogwok, Emmanuel; Ilyas, Muhammad; Alicai, Titus; Rey, Marie E C; Taylor, Nigel J

    2016-04-01

    Infection of plant cells by viral pathogens triggers RNA silencing, an innate antiviral defense mechanism. In response to infection, small RNAs (sRNAs) are produced that associate with Argonaute (AGO)-containing silencing complexes which act to inactivate viral genomes by posttranscriptional gene silencing (PTGS). Deep sequencing was used to compare virus-derived small RNAs (vsRNAs) in cassava genotypes NASE 3, TME 204 and 60444 infected with the positive sense single-stranded RNA (+ssRNA) viruses cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV), the causal agents of cassava brown streak disease (CBSD). An abundance of 21-24nt vsRNAs was detected and mapped, covering the entire CBSV and UCBSV genomes. The 21nt vsRNAs were most predominant, followed by the 22 nt class with a slight bias toward sense compared to antisense polarity, and a bias for adenine and uracil bases present at the 5'-terminus. Distribution and frequency of vsRNAs differed between cassava genotypes and viral genomes. In susceptible genotypes TME 204 and 60444, CBSV-derived sRNAs were seen in greater abundance than UCBSV-derived sRNAs. NASE 3, known to be resistant to UCBSV, accumulated negligible UCBSV-derived sRNAs but high populations of CBSV-derived sRNAs. Transcript levels of cassava homologues of AGO2, DCL2 and DCL4, which are central to the gene-silencing complex, were found to be differentially regulated in CBSV- and UCBSV-infected plants across genotypes, suggesting these proteins play a role in antiviral defense. Irrespective of genotype or viral pathogen, maximum populations of vsRNAs mapped to the cytoplasmic inclusion, P1 and P3 protein-encoding regions. Our results indicate disparity between CBSV and UCBSV host-virus interaction mechanisms, and provide insight into the role of virus-induced gene silencing as a mechanism of resistance to CBSD.

  13. Comparative analysis of virus-derived small RNAs within cassava (Manihot esculenta Crantz) infected with cassava brown streak viruses.

    Science.gov (United States)

    Ogwok, Emmanuel; Ilyas, Muhammad; Alicai, Titus; Rey, Marie E C; Taylor, Nigel J

    2016-04-01

    Infection of plant cells by viral pathogens triggers RNA silencing, an innate antiviral defense mechanism. In response to infection, small RNAs (sRNAs) are produced that associate with Argonaute (AGO)-containing silencing complexes which act to inactivate viral genomes by posttranscriptional gene silencing (PTGS). Deep sequencing was used to compare virus-derived small RNAs (vsRNAs) in cassava genotypes NASE 3, TME 204 and 60444 infected with the positive sense single-stranded RNA (+ssRNA) viruses cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV), the causal agents of cassava brown streak disease (CBSD). An abundance of 21-24nt vsRNAs was detected and mapped, covering the entire CBSV and UCBSV genomes. The 21nt vsRNAs were most predominant, followed by the 22 nt class with a slight bias toward sense compared to antisense polarity, and a bias for adenine and uracil bases present at the 5'-terminus. Distribution and frequency of vsRNAs differed between cassava genotypes and viral genomes. In susceptible genotypes TME 204 and 60444, CBSV-derived sRNAs were seen in greater abundance than UCBSV-derived sRNAs. NASE 3, known to be resistant to UCBSV, accumulated negligible UCBSV-derived sRNAs but high populations of CBSV-derived sRNAs. Transcript levels of cassava homologues of AGO2, DCL2 and DCL4, which are central to the gene-silencing complex, were found to be differentially regulated in CBSV- and UCBSV-infected plants across genotypes, suggesting these proteins play a role in antiviral defense. Irrespective of genotype or viral pathogen, maximum populations of vsRNAs mapped to the cytoplasmic inclusion, P1 and P3 protein-encoding regions. Our results indicate disparity between CBSV and UCBSV host-virus interaction mechanisms, and provide insight into the role of virus-induced gene silencing as a mechanism of resistance to CBSD. PMID:26811902

  14. Effects of supplementing cassava peels with cassava leaves and cowpea haulms on the performance, intake, digestibility and nitrogen utilization of West African Dwarf goats.

    Science.gov (United States)

    Abatan, Oluwayemisi; Oni, Adebayo Olusoji; Adebayo, Kolawole; Iposu, Shamusideen; Sowande, Olusiji Sunday; Onwuka, Chryss Friday Ijeoma

    2015-01-01

    A 16-week experiment was conducted to determine the utilization of ratios of cassava leaf meal, cassava peel and cowpea haulms by West African Dwarf (WAD) goats. Thirty WAD bucks aged 8 ± 1.3 months with body weights of 6-6.5 ± 0.12 kg were divided into five groups of six animals and each group randomly assigned to one of the treatments in a completely randomized design. The five dietary treatments were formulated to contain cassava peels, leaves and cowpea haulms at different proportions of 700:100:175 (T1), 500:200:275 (T2), 300:300:375 (T3) and 100:400:475 (T4) g/kg dry matter (DM), respectively. A standard diet formulated to meet the nutrient requirement of the animals with no cassava and cowpea haulms was used as the control diet (T5). DM intake ranged from 316.16 to 458.73 g/day and significantly increased (linear (L), quadratic (Q), cubic (C): P cassava peels reduced and cassava leaves and cowpea haulms increased in the diets. The crude protein (CP) intake significantly increased (L, Q, C: P cassava peels reduced and cassava leaves and cowpea haulms increased in the diets. Growth rate values significantly (L: P cassava leaves and cowpea haulms increased and reduced cassava peels in the diets. The highest N intake of 14.75 g/day obtained in T4 was significantly (L: P cassava peels, leaves and cowpea haulms in the proportion of 100:400:475 g/kg DM improved the growth and digestibility of WAD goats and can therefore be used to sustain animal performance during the dry season in a total mixed ration.

  15. Whitefly Bemisia tabaci (Homoptera: Aleyrodidae) infestation on cassava genotypes grown at different ecozones in Nigeria.

    Science.gov (United States)

    Ariyo, O A; Dixon, A G O; Atiri, G I

    2005-04-01

    Large-scale screening of cassava, Manihot esculenta Crantz, genotypes for resistance to infestation by whitefly Bemisia tabaci Gennadius, the vector of cassava mosaic geminiviruses, is limited. A range of new cassava elite clones were therefore assessed for the whitefly infestation in the 1999/2000 and 2000/2001 cropping seasons in experimental fields of International Institute of Tropical Agriculture, Ibadan, Nigeria. On each scoring day, between 0600 and 0800 hours when the whiteflies were relatively immobile, adult whitefly populations on the five topmost expanded leaves of cassava cultivars were counted. All through the 6-mo scoring period, there was a highly significant difference in whitefly infestation among the new cassava elite clones. Vector population buildup was observed in Ibadan (forest-savanna transition zone) and Onne (humid forest), 2 mo after planting (MAP). Mean infestation across cassava genotypes was significantly highest (16.6 whiteflies per plant) in Ibadan and lowest in Zaria (0.2). Generally, whitefly infestation was very low in all locations at 5 and 6 MAP. During this period, cassava genotypes 96/1439 and 91/02324 significantly supported higher infestations than other genotypes. Plants of 96/1089A and TMS 30572 supported the lowest whitefly infestation across cassava genotypes in all locations. The preferential whitefly visitation, the differences between locations in relation to whitefly population, cassava mosaic disease, and the fresh root yield of cassava genotypes are discussed.

  16. Socio-economic Analysis of Cassava Marketing in Benue State, Nigeria

    Directory of Open Access Journals (Sweden)

    Benjamin C. Asogwa

    2013-04-01

    Full Text Available The purpose of this study is to analyze the socio-economics of cassava marketing in Benue State, Nigeria. Data were collected from randomly sampled 107 cassava marketers in Benue State, using a structured questionnaire. The study revealed that most of the cassava marketers had secondary education (72.9%. The study also revealed that marketing of cassava is mostly undertaken by females (57%. The result showed that married people (59.8% were mostly involved in the marketing of cassava. The study revealed that cassava marketing is operated in a competitive market environment and the marketing margin obtained by an average cassava marketer is 31%. Cassava marketing is a profitable venture in the study area. It was also revealed that greater percentage of cassava traded in the study area was primarily obtained from the farmers. Majority of the respondents (92.5% belong to cassava marketing association. The most pressing problem (46.73% faced by the marketers is high taxes during transportation. Majority of the cassava marketers use the revenue generated from cassava business to train their children in schools and buildings of modern houses (57.0.There is the need to: open centralized cassava market in the study area; construct good network of feeder roads; establish processing companies/facilities; restructure the entire marketing system. Traders should be encouraged to form agricultural marketing cooperatives in order to eliminate the exploitative activities of the middlemen. Marketing agencies should be enforced by government to take care of the marketing problems that are associated with the speculative activities of the middlemen.

  17. Determinants Of Export-Led Cassava Production Intensification Among Small-Holder Farmers in Delta State, Nigeria

    Directory of Open Access Journals (Sweden)

    Achoja, F. O.

    2012-06-01

    Full Text Available Determinants of export-led cassava production intensification among small-holder farmers were investigated. Primary data collected with structured questionnaire from randomly selected 60 respondents, were analysed using appropriate statistics. The result showed a slow increasing trend in response to export opportunities. Farm size, credit availability, cassava product domestic prices, labour and frequency of extension contact had positive effect on cassava output while existence of efficient marketing system has negative effect on cassava output. Inadequate finance and high cost of labour were the problems facing cassava production intensification. Policy instrument on cassava production intensification should capture the significant determinants identified in the study.

  18. Genome-wide association and prediction analysis in African cassava (Manihot esculenta) reveals the genetic architecture of resistance to cassava mosaic disease and prospects for rapid genetic improvement

    Science.gov (United States)

    Cassava (Manihot esculenta) is a crucial, under-researched crop feeding millions worldwide, especially in Africa. Cassava mosaic disease (CMD) has plagued production in Africa for over a century. Bi-parental mapping studies suggest primarily a single major gene mediates resistance. To be certain and...

  19. The microbiota of Lafun, an african traditional cassava food product

    DEFF Research Database (Denmark)

    Padonou, Sègla Wilfrid; Nielsen, Dennis Sandris; Hounhouigan, Joseph D.;

    2009-01-01

    Lafun is a fermented cassava food product consumed in parts of West Africa. In the present work the microorganisms (aerobic bacteria (AB), lactic acid bacteria (LAB) and yeasts) associated with the fermentation of Lafun under traditional conditions have for the first time been studied using...

  20. Development of comprehensive medium for micropropagation of cultivated Cassava accessions

    Science.gov (United States)

    Cassava is one of the most important foods in the human diet in the tropics, where it ranks fifth as a source of energy, after rice, sugar cane, and maize. Since it is a vegetative propagated crop, the use of in vitro propagation is very important to preserve germplasm free of pest and diseases. M...

  1. Determination of aflatoxin in processed dried cassava root

    DEFF Research Database (Denmark)

    Gnonlonfin, Gbemenou Joselin Benoit; Katerere, David R.; Adjovi, Yann;

    2010-01-01

    A new method that uses HPLC with a photochemical reactor for enhanced detection was developed and validated for the determination of aflatoxins in cassava flour. Samples were spiked with a mixture of four aflatoxins at 5, 10, and 20 microg/kg mixed with either 1 or 5 g NaCI and extracted with met...

  2. Energy and greenhouse gas balances of cassava-based ethanol

    NARCIS (Netherlands)

    Thanh, Le L.; Ierland, van E.C.; Zhu, X.; Wesseler, J.H.H.

    2013-01-01

    Biofuel production has been promoted to save fossil fuels and reduce greenhouse gas (GHG) emissions. However, there have been concerns about the potential of biofuel to improve energy efficiency and mitigate climate change. This paper investigates energy efficiency and GHG emission saving of cassava

  3. Mathematical Modelling Of Cyanide Inhibition on Cassava Wastewater Treatment

    Directory of Open Access Journals (Sweden)

    E. Onukwugha

    2013-09-01

    Full Text Available Anaerobic Baffled Reactors (ABR is used to evaluate the extent of cyanide inhibition of cassava wastewater treatment. The reactor has aspect ratio of 4:1:1. Kinetic analyses of specific growth rate μmax and half saturation constant

  4. Transcriptome response of cassava leaves under natural shade.

    Science.gov (United States)

    Ding, Zehong; Zhang, Yang; Xiao, Yi; Liu, Fangfang; Wang, Minghui; Zhu, Xinguang; Liu, Peng; Sun, Qi; Wang, Wenquan; Peng, Ming; Brutnell, Tom; Li, Pinghua

    2016-01-01

    Cassava is an important staple crop in tropical and sub-tropical areas. As a common farming practice, cassava is usually cultivated intercropping with other crops and subjected to various degrees of shading, which causes reduced productivity. Herein, a comparative transcriptomic analysis was performed on a series of developmental cassava leaves under both full sunlight and natural shade conditions. Gene expression profiles of these two conditions exhibited similar developmental transitions, e.g. genes related to cell wall and basic cellular metabolism were highly expressed in immature leaves, genes involved in lipid metabolism and tetrapyrrole synthesis were highly expressed during the transition stages, and genes related to photosynthesis and carbohydrates metabolism were highly expressed in mature leaves. Compared with the control, shade significantly induced the expression of genes involved in light reaction of photosynthesis, light signaling and DNA synthesis/chromatin structure; however, the genes related to anthocyanins biosynthesis, heat shock, calvin cycle, glycolysis, TCA cycle, mitochondrial electron transport, and starch and sucrose metabolisms were dramatically depressed. Moreover, the shade also influenced the expression of hormone-related genes and transcriptional factors. The findings would improve our understanding of molecular mechanisms of shade response, and shed light on pathways associated with shade-avoidance syndrome for cassava improvement. PMID:27539510

  5. Transcriptome response of cassava leaves under natural shade.

    Science.gov (United States)

    Ding, Zehong; Zhang, Yang; Xiao, Yi; Liu, Fangfang; Wang, Minghui; Zhu, Xinguang; Liu, Peng; Sun, Qi; Wang, Wenquan; Peng, Ming; Brutnell, Tom; Li, Pinghua

    2016-01-01

    Cassava is an important staple crop in tropical and sub-tropical areas. As a common farming practice, cassava is usually cultivated intercropping with other crops and subjected to various degrees of shading, which causes reduced productivity. Herein, a comparative transcriptomic analysis was performed on a series of developmental cassava leaves under both full sunlight and natural shade conditions. Gene expression profiles of these two conditions exhibited similar developmental transitions, e.g. genes related to cell wall and basic cellular metabolism were highly expressed in immature leaves, genes involved in lipid metabolism and tetrapyrrole synthesis were highly expressed during the transition stages, and genes related to photosynthesis and carbohydrates metabolism were highly expressed in mature leaves. Compared with the control, shade significantly induced the expression of genes involved in light reaction of photosynthesis, light signaling and DNA synthesis/chromatin structure; however, the genes related to anthocyanins biosynthesis, heat shock, calvin cycle, glycolysis, TCA cycle, mitochondrial electron transport, and starch and sucrose metabolisms were dramatically depressed. Moreover, the shade also influenced the expression of hormone-related genes and transcriptional factors. The findings would improve our understanding of molecular mechanisms of shade response, and shed light on pathways associated with shade-avoidance syndrome for cassava improvement.

  6. Extracellular enzyme activities during cassava fermentation for 'fufu' production.

    Science.gov (United States)

    Oyewole, O B; Odunfa, S A

    1992-01-01

    Amylase and pectin methyl esterase activities increased rapidly during the early period of the fermentation of cassava for 'fufu' production, attaining their peak activities after 12 and 24h, respectively. Cellulase activity was lower and approximately constant for most of the fermentation period.

  7. Transcriptional response to petiole heat girdling in cassava

    Science.gov (United States)

    The heat-girdling technique, which is known to inhibit photoassimilate translocation, was performed on the petiole of cassava leaves at the end of the light cycle to inhibit starch remobilization during the night. The inhibition of starch remobilization caused significant starch accumulation at the ...

  8. Cassava tissue culture and long-term preservation

    Science.gov (United States)

    Cassava (Manihot esculenta Crantz) is cultivated mainly for its starchy roots as an important staple food for the tropics. M. esculenta is the only cultivated species in the genus Manihot, which contains 98 species, mostly native to Brazil. In recent years several research groups have reported metho...

  9. Sino-Swiss center for cassava technology launched in Shanghai

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Under the joint sponsorship of the Shanghai Institutes for Biological Sciences (SIBS) and Swiss Federal Institute of Technology (ETH Zurich), the Shanghai Center for Cassava Biotechnology (SCCB) has been established at the Shanghai Institute of Plant Physiology and Ecology(SIPE), SIBS.

  10. Field experiment on transgenic cassava proves successful in South China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ A pioneer study on field tests of transgenic cassava (Manihot esculenta Crantz) by a Sino-Swiss research consortium has proved successful. The experiment was carried out in 2006 at an experimental station in Haikou, capital of south China's Hainan Province.

  11. Functional genomic analysis of cassava proteins with TIR domains

    International Nuclear Information System (INIS)

    Proteins containing a TIR domain (toll interleukin receptor) are involved in plant and animal immunity. The aim of this work was to carry out an overall genomic analysis of cassava proteins with a TIR domain and discern their possible role in resistance to cassava bacterial blight. In total 46 proteins with a TIR domain were identified in the cassava proteome and were classed in four categories according the presence or absence of other domains: TIR (T), TIR -NB (TN), TIR - lRR (TL) and TIR - NB - lRR (TNL). 56.6 % of these 46 proteins have TIR, NB and lRR domains. Using multiple alignments it was possible to demonstrate that not all cassava TIR domains contain the AE region, involved in dimerization and activation of immune responses. Three of the four proteins categories (T, TNL and TN) presented a higher number of synonymous substitutions suggesting that they are not involved in recognition process. two TIR domains not presenting the ae region were analyzed by yeast two hybrid assays and by agro-infiltration, finding that both are able to form homo and heterodimers, but they do not trigger defense responses. With this study it was possible to conclude that TIR domains can function as adaptors in the signal transduction with other resistance proteins. In addition, it became clear that not always the AE region is important for TIR dimerization but it seems necessary to activate defense responses signals.

  12. Ethanol production of banana shell and cassava starch

    International Nuclear Information System (INIS)

    In this work the acid hydrolysis of the starch was evaluated in cassava and the cellulose shell banana and its later fermentation to ethanol, the means of fermentation were adjusted for the microorganisms saccharomyces cerevisiae nrrl y-2034 and zymomonas mobilis cp4. The banana shell has been characterized, which possesses a content of starch, cellulose and hemicelluloses that represent more than 80% of the shell deserve the study of this as source of carbon. The acid hydrolysis of the banana shell yield 20g/l reducing sugar was obtained as maximum concentration. For the cassava with 170 g/l of starch to ph 0.8 in 5 hours complete conversion is achieved to you reducing sugars and any inhibitory effect is not noticed on the part of the cultivations carried out with banana shell and cassava by the cyanide presence in the cassava and for the formation of toxic compounds in the acid hydrolysis the cellulose in banana shell. For the fermentation carried out with saccharomyces cerevisiae a concentration of ethanol of 7.92± 0.31% it is achieved and a considerable production of ethanol is not appreciated (smaller than 0.1 g/l) for none of the means fermented with zymomonas mobilis

  13. Properties of Cassava Starch Modified by Amylomaltase from Corynebacterium glutamicum.

    Science.gov (United States)

    Suriyakul Na Ayudhaya, Pitcha; Pongsawasdi, Piamsook; Laohasongkram, Kalaya; Chaiwanichsiri, Saiwarun

    2016-06-01

    Amylomaltase (α-1,4-glucanotransferase, AM; EC 2.4.1.25) from Corynebacterium glutamicum expressed in Escherichia coli was used to prepare the enzyme-modified cassava starch for food application. About 5% to 15% (w/v) of cassava starch slurries were incubated with 1, 3, or 5 units of amylomaltase/g starch. Apparent amylose, amylopectin chain length distribution, thermal properties, freeze-thaw stability, thermo-reversibility, and gel strength of the obtained modified starches were measured. The apparent amylose content and retrogradation enthalpy were lower, whereas the retrogradation temperatures, freeze-thaw stability, and thermo-reversibility were higher than those of the native cassava starch. However, when amylomaltase content was increased to 20 units of amylomaltase/g starch and for 24 h, the modified starch showed an improvement in the thermo-reversibility property. When used in panna cotta, the gel strength of the sample using the 20 units/24 h modified cassava starch was similar to that of using gelatin. PMID:27105125

  14. Response of cassava genotypes to different micropropagation media

    Science.gov (United States)

    Cassava is one of the most important staple foods in the human diet in the tropics, where it ranks fourth as a source of energy, after rice, sugar cane and maize. Since it is a vegetative propagated crop, the use of in vitro propagation is very important to preserve the germplasm free of pest and di...

  15. Uncertainty in life cycle economical analysis of cassava-based ethanol fuel

    Institute of Scientific and Technical Information of China (English)

    LENG Ru-bo; DAI Du; CHEN Xiao-jun; WANG Cheng-tao

    2005-01-01

    Biomass ethanol fuel is not only renewable but also environmental-friendly. Guangxi Zhuang Autonomous Region is developing the cassava-based ethanol fuel. Economical performance of the project is the key issue.The traditional life cycle economical analysis is just a static calculation process. Uncertainty is the character of cassava yield, cost of cassava plant, cassava price, tax rate and gasoline price, and the economical performance of the project is determined by these aspects. This study proposes an economical model of cassava-based ethanol fuel. The method of Monte Carol is used to simulate the economical performance. This method conquers the shortage of the traditional way. The results show that cassava-based ethanol fuel can get survived when the tax is exempted. Finally, the study also evaluates the potential of the economical performance.

  16. Analyses of Twelve New Whole Genome Sequences of Cassava Brown Streak Viruses and Ugandan Cassava Brown Streak Viruses from East Africa: Diversity, Supercomputing and Evidence for Further Speciation.

    Science.gov (United States)

    Ndunguru, Joseph; Sseruwagi, Peter; Tairo, Fred; Stomeo, Francesca; Maina, Solomon; Djikeng, Appolinaire; Djinkeng, Appolinaire; Kehoe, Monica; Boykin, Laura M

    2015-01-01

    Cassava brown streak disease is caused by two devastating viruses, Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV) which are frequently found infecting cassava, one of sub-Saharan Africa's most important staple food crops. Each year these viruses cause losses of up to $100 million USD and can leave entire families without their primary food source, for an entire year. Twelve new whole genomes, including seven of CBSV and five of UCBSV were uncovered in this research, doubling the genomic sequences available in the public domain for these viruses. These new sequences disprove the assumption that the viruses are limited by agro-ecological zones, show that current diagnostic primers are insufficient to provide confident diagnosis of these viruses and give rise to the possibility that there may be as many as four distinct species of virus. Utilizing NGS sequencing technologies and proper phylogenetic practices will rapidly increase the solution to sustainable cassava production. PMID:26439260

  17. Analyses of Twelve New Whole Genome Sequences of Cassava Brown Streak Viruses and Ugandan Cassava Brown Streak Viruses from East Africa: Diversity, Supercomputing and Evidence for Further Speciation.

    Directory of Open Access Journals (Sweden)

    Joseph Ndunguru

    Full Text Available Cassava brown streak disease is caused by two devastating viruses, Cassava brown streak virus (CBSV and Ugandan cassava brown streak virus (UCBSV which are frequently found infecting cassava, one of sub-Saharan Africa's most important staple food crops. Each year these viruses cause losses of up to $100 million USD and can leave entire families without their primary food source, for an entire year. Twelve new whole genomes, including seven of CBSV and five of UCBSV were uncovered in this research, doubling the genomic sequences available in the public domain for these viruses. These new sequences disprove the assumption that the viruses are limited by agro-ecological zones, show that current diagnostic primers are insufficient to provide confident diagnosis of these viruses and give rise to the possibility that there may be as many as four distinct species of virus. Utilizing NGS sequencing technologies and proper phylogenetic practices will rapidly increase the solution to sustainable cassava production.

  18. Nitrogen requirements of cassava in selected soils of Thailand

    Directory of Open Access Journals (Sweden)

    Jakchaiwat Kaweewong

    2013-08-01

    Full Text Available Cassava (Manihot esculenta is one of the most important export crops in Thailand, yet the nitrogen requirement is unknown and not considered by growers and producers. Cassava requirements for N were determined in field experiments during a period of four years and four sites on the Satuk (Suk, Don Chedi (Dc, Pak Chong (Pc,and Ban Beung (BBg soil series in Lopburi, Supanburi, Nakhon Ratchasima, and Chonburi sites, respectively. The fertilizer treatment structure comprised 0, 62.5, 125, 187.5, 250 and 312.5 kg N ha^(-1 as urea. At each site cassava was harvested at nine months and yield parameters and the minimum datasets were taken. The fertilizer rate which resulted in maximum yield ranged from 187.5 kg N ha^(-1 in Supanburi and Chonburi (fresh weight yield of 47,500 and 30,000 kg ha^(-1 respectively to 250 kg N ha^(-1 in Lopburi and Nakhon Ratchasima (fresh weight yield of 64,100 and 46,700 kg ha^(-1 respectively. Yield appeared to decrease at the higher, 312 kg ha^(-1, at Supanburi and Lopburi, and 250 kg ha^(-1 (Chonburi fertilizer N rates. Net revenue was 70.4 and 72.9 % higher than where no N was appliedLopburi and Nakhon Ratchasima sites. Net revenue at the Supanburi and Chonburi sites were 53.8 and 211.0 % higher than that where no N was applied. This study suggests that at all sites improved cassava production and net revenue could be obtained with the judicious application of higher quantities of N. The results provide needed guidance to nitrogen fertilization of the important industrial crop cassava in Thailand.

  19. Labour Arrangements in Cassava Production in Oyo State, Nigeria

    Directory of Open Access Journals (Sweden)

    Abila, N.

    2012-01-01

    Full Text Available The study examined the effects of labour arrangements on the profitability of cassava enterprises in Oyo North Area of Oyo State, Nigeria. A multi-stage sampling technique was adopted for data collection, while data were analysed using descriptive statistics and budgetary analysis. The results show that the prevalent labour arrangements for cassava enterprises are: a combination of Family, Hired and Contract labour (38.9%; Family-Hired labour (27.8%; Family-Contract labour (31.1%. The gross margin per hectares across labour arrangements are N279481.99 (all-labour, N286044.24 (family-hired, N216940.10 (familycontract, and N235000.00 (family only. The returns on a naira invested on variable costs across different labour arrangements for cassava enterprises are N2.04 (all-labour, N3.66 (family-hired, N2.37 (familycontract, and N2.61 (family only. This implies that a unit (N1 variable cost in the various labour arrangements of all-labour, family/hired, family/contract and family only in cassava production will yield a marginal return of N3.04, N3.66, N2.37 and N2.61 respectively. Family-hired labour arrangement yields higher marginal return per unit of manday and one naira spent than all other arrangements. The study recommends among others the application of laboursaving technologies and an optimum combination of various labour arrangements to reduce the cost of labour used in cassava production.

  20. Reprogramming of cassava (Manihot esculenta) microspores towards sporophytic development.

    Science.gov (United States)

    Perera, P I P; Ordoñez, C A; Dedicova, B; Ortega, P E M

    2014-05-21

    Gametes have the unique potential to enter the sporophytic pathway, called androgenesis. The plants produced are usually haploid and recombinant due to the preceding meiosis and they can double their chromosome number to form doubled haploids, which are completely homozygous. Availability of the doubled haploids facilitates mapping the genes of agronomically important traits, shortening the time of the breeding process required to produce new hybrids and homozygous varieties, and saving the time and cost for inbreeding. This study aimed to test the feasibility of using isolated and in vitro cultured immature cassava (Manihot esculenta) microspores to reprogramme and initiate sporophytic development. Different culture media and different concentrations of two ion components (Cu(2+) and Fe(2+)) were tested in two genotypes of cassava. External structural changes, nuclear divisions and cellular changes during reprogramming were analysed by scanning electron microscopy, by staining with 4',6-diamidino-2-phenylindole, and through classical histology and transmission electron microscopy. In two cassava genotypes, different developmental stages of microspores were found to initiate sporophytic cell divisions, that is, with tetrads of TMS 60444 and with mid or late uni-nucleate microspores of SM 1219-9. In the modified NLN medium (NLNS), microspore enlargements were observed. The medium supplemented with either sodium ferrous ethylene-diamine-tetraacetic acid (NaFeEDTA) or CuSO4·5H2O induced sporophytic cell division in both genotypes. A low frequency of the reprogramming and the presence of non-responsive microspores among the responsive ones in tetrads were found to be related to the viability and exine formation of the microspores. The present study clearly demonstrated that reprogramming occurs much faster in isolated microspore culture than in anther culture. This paves the way for the development of an efficient technique for the production of homozygous lines in

  1. Cassava about-FACE: Greater than expected yield stimulation of cassava (Manihot esculenta) by future CO2 levels

    Science.gov (United States)

    The potential for tuber crops such as cassava, yams and potatoes to enhance food security in the future is underestimated. In tuber crops there is the potential for a much higher ratio of edible to non-edible components than in above ground grain and bean crops such as rice, wheat, maize or soybean....

  2. Ipomoviruses: Squash vein yellowing virus, Cucumber vein yellowing virus, Cassava brown streak virus, and Ugandan cassava brown streak virus

    Science.gov (United States)

    Ipomoviruses including Squash vein yellowing virus, Cucumber vein yellowing virus and Cassava brown streak virus are currently causing significant economic impact on crop production in several regions of the world. Only recently have results of detailed characterization of their whitefly transmissi...

  3. Cassava stillage and its anaerobic fermentation liquid as external carbon sources in biological nutrient removal*

    OpenAIRE

    Bu, Fan; Hu, Xiang; Xie, Li; Zhou, Qi

    2015-01-01

    The aim of this study was to investigate the effects of one kind of food industry effluent, cassava stillage and its anaerobic fermentation liquid, on biological nutrient removal (BNR) from municipal wastewater in anaerobic-anoxic-aerobic sequencing batch reactors (SBRs). Experiments were carried out with cassava stillage supernatant and its anaerobic fermentation liquid, and one pure compound (sodium acetate) served as an external carbon source. Cyclic studies indicated that the cassava by-p...

  4. Influence of cassava genotype and composite flours’ substitution level on rheological behaviour during bread-making

    OpenAIRE

    Sergio Henao Osorio; Johanna Aristizábal Galvis

    2010-01-01

    Given increasing dependence on imported wheat, studies have been carried out in Colombia regarding the use of composite wheat-cassava flour in bread-making. A project was carried out from 1986-1991 in which different cassava genotypes, harvest ages, substitution levels and bread acceptability were evaluated. However, these studies did not have any effect on the baking sector because a constant supply of high quality, high volume and reasonably-priced cassava flour was lacking. Based on these ...

  5. Effect of carboxymethyl cellulose concentration on physical properties of biodegradable cassava starch-based films

    OpenAIRE

    Sriburi Pensiri; Wongruong Sasitorn; Mauer Lisa J; Tongdeesoontorn Wirongrong; Rachtanapun Pornchai

    2011-01-01

    Abstract Background Cassava starch, the economically important agricultural commodity in Thailand, can readily be cast into films. However, the cassava starch film is brittle and weak, leading to inadequate mechanical properties. The properties of starch film can be improved by adding plasticizers and blending with the other biopolymers. Results Cassava starch (5%w/v) based films plasticized with glycerol (30 g/100 g starch) were characterized with respect to the effect of carboxymethyl cellu...

  6. Thermoanalytical and starch content evaluation of cassava bagasse as agro-industrial residue

    OpenAIRE

    Luiz Gustavo Lacerda; Rafael Ramires Almeida; Ivo Mottin Demiate; Marco Aurélio Silva Carvalho Filho; Eliane Carvalho Vasconcelos; Adenise Lorenci Woiciechowski; Gilbert Bannach; Egon Schnitzler; Carlos Ricardo Soccol

    2009-01-01

    Starch nutritional fractions as well as thermal properties and other analysis are essential for food and industrial application. Cassava bagasse is an important agro-industrial residue and its starch content was evaluated using two alternative methods. Thermal characterization and microscopy analyses helped to understand how hydrolysis digests starchy fraction of cassava bagasse. The melting point of cassava starch occurred at 169.2ºC. Regarding TG analyses, after moisture content, there were...

  7. Physiological and molecular characterization of drought responses and identification of candidate tolerance genes in cassava

    OpenAIRE

    Turyagyenda, Laban F.; Kizito, Elizabeth B.; Ferguson, Morag; Baguma, Yona; Agaba, Morris; Jagger J W Harvey; Osiru, David S. O.

    2013-01-01

    Cassava is an important root crop to resource-poor farmers in marginal areas, where its production faces drought stress constraints. Given the difficulties associated with cassava breeding, a molecular understanding of drought tolerance in cassava will help in the identification of markers for use in marker-assisted selection and genes for transgenic improvement of drought tolerance. This study was carried out to identify candidate drought-tolerance genes and expression-based markers of droug...

  8. Correlation of chemical compositions of cassava varieties to their resistance to Prostephanus truncatus Horn (Coleoptera: Bostrichidae).

    Science.gov (United States)

    Osipitan, Adebola A; Sangowusi, Victoria T; Lawal, Omoniyi I; Popoola, Kehinde O

    2015-01-01

    The preference of cassava as a major host by Prostephanus truncatus Horn is a major constraint to ample production of cassava, Manihot esculenta Crantz and storage. This study analyzed the nutritional and secondary metabolite compositions in 15 cassava varieties, evaluated levels of damage and reproduction by P. truncatus, and assessed their resistance to attack. One hundred grams of dried cassava chips in 250-ml Kilner jars were infested with 10 adult larger grain borerof 0-10 days old and held for 3 months. The nutritional and secondary metabolites compositions of the dry cassava chips were determined using the method of Association of Analytical Chemists . Chip perforation rates in the cassava varieties ranged from 17.7 to 71.6%. The weight of cassava powder varied by about threefold. The final number of larger grain borer in the cassava varieties varied by about sixfold with 63 in 01/0040 and 379 in 01/1368. Hydrocyanic acid content content varied by over 10-fold and correlated negatively with number of larger grain borer. Flavonoid content varied by ∼10%. Tannins and saponin content of the cassava negatively correlated with number of adult P. truncatus. The cassava varieties 95/0166, 92/0326, 01/0040, 05/0024, and 34 91934 had selection index 0.8 were classified as susceptible. The resistance to high damage in the resistant varieties was conferred by secondary metabolites such as tannins, saponins, alkaloids, and hydrocyanic acid content. The genetic variation in cassava varieties could be explored to breed resistant cassava varieties for use in larger grain borer-endemic areas.

  9. False beliefs on the socio-economic drivers of cassava cropping

    OpenAIRE

    Fermont, van, A.M.; Babirye, A.; Obiero, H.M.; Abele, S; Giller, K.E.

    2010-01-01

    General belief has it that cassava is (i) a subsistence crop, grown to avoid hunger (ii) by poor farmers, (iii) predominantly as an intercrop, (iv) requiring less labour than other crops and (v) no inputs. These beliefs influence policy, project development and implementation, and if wrong, may have far-reaching consequences for the success and sustainability of interventions. This study examines five beliefs about cassava and discusses consequences for interventions targeting cassava. From 2...

  10. A crop of one's own? Women’s experiences of cassava commercialization in Nigeria and Malawi

    OpenAIRE

    Forsythe, Lora; Posthumus, Helena; Martin, Adrienne

    2016-01-01

    Improving the effectiveness of agricultural markets for economic growth and poverty reduction has been a central focus for development initiatives, particularly in Sub-Saharan Africa. Staple crops with low input requirements and drought tolerance, such as cassava, are being promoted for market development due to their accessibility for poor smallholder farmers. Narratives often equate commercialization of cassava to benefits for women, as cassava is commonly labelled a ‘women’s crop’. However...

  11. The retail market for fresh cassava root tubers in the European Union (EU)

    DEFF Research Database (Denmark)

    Kolind-Hansen, Lotte; Brimer, Leon

    2010-01-01

    A number of retail shops in Copenhagen sell fresh cassava roots. Cassava roots contain the toxic cyanogenic glucoside linamarin. A survey was made of the shop characteristics, origin of the roots, buyers, shop owner's knowledge of toxicity levels, and actual toxicity levels.......A number of retail shops in Copenhagen sell fresh cassava roots. Cassava roots contain the toxic cyanogenic glucoside linamarin. A survey was made of the shop characteristics, origin of the roots, buyers, shop owner's knowledge of toxicity levels, and actual toxicity levels....

  12. Effects of Processing on the Chemical and Anti-nutritional Properties of Cassava Roots

    OpenAIRE

    Omosuli SV

    2014-01-01

    The nutritive and antinutritive composition of cassava roots (raw and boiled) was investigated. The proximate composition of raw and boiled cassava tubers was not significantly different (P> 0.05), except in moisture, fat, carbohydrate and Energy value. High levels of the antinutrients in raw cassava tubers (20.56mg/100g Tannins; 1,16mg/100g oxalate and 3.36mg/100g phytate) make them unsafe and unsuitable for human consumption except after processing. Mineral contents of cassava tubers were n...

  13. The Potency and Utilization of Cassava and Sweet Potato Leaves as Feed Resources for Small Ruminant

    OpenAIRE

    Juniar Sirait; K Simanihuruk

    2010-01-01

    Cassava and sweet potato leaves are agricultural byproducts which are potential to be utilized as feed for small ruminants. In year 2009, it is assumed that dry matter productions of cassava and sweet potato leaves are 2,590,929 and 348,008 tons, respectively. Cassava and sweet potato leaves, both contain high level of protein (> 20%) so that they are good protein sources for goats. Cassava leaves, however, contain cyanide acid (HCN) that varied depended on the age and require wilting process...

  14. Unraveling complex viral infections in cassava (Manihot esculenta Crantz) from Colombia.

    Science.gov (United States)

    Carvajal-Yepes, Monica; Olaya, Cristian; Lozano, Ivan; Cuervo, Maritza; Castaño, Mauricio; Cuellar, Wilmer J

    2014-06-24

    In the Americas, different disease symptoms have been reported in cassava including leaf mosaics, vein clearings, mottles, ring spots, leaf distortions and undeveloped and deformed storage roots. Some viruses have been identified and associated with these symptoms while others have been reported in symptomless plants or latent infections. We observed that reoviruses associated with severe root symptoms (RS) of Cassava Frogskin Disease (CFSD) are not associated with leaf symptoms (LS) observed in the cassava indicator plant 'Secundina'. Neither were these LS associated with the previously characterized Cassava common mosaic virus, Cassava virus X, Cassava vein mosaic virus or phytoplasma, suggesting the presence of additional pathogens. In order to explain LS observed in cassava we used a combination of biological, serological and molecular tests. Here, we report three newly described viruses belonging to the families Secoviridae, Alphaflexiviridae and Luteoviridae found in cassava plants showing severe RS associated with CFSD. All tested plants were infected by a mix of viruses that induced distinct LS in 'Secundina'. Out of the three newly described viruses, a member of family Secoviridae could experimentally induce LS in single infection. Our results confirm the common occurrence of complex viral infections in cassava field-collected since the 1980s.

  15. Promoting Cassava as an Industrial Crop in Ghana: Effects on Soil Fertility and Farming System Sustainability

    OpenAIRE

    Adjei-Nsiah, S.; Owuraku Sakyi-Dawson

    2012-01-01

    Cassava is an important starchy staple crop in Ghana with per capita consumption of 152.9 kg/year. Besides being a staple food crop, cassava can be used as raw material for the production of industrial starch and ethanol. The potential of cassava as an industrial commercial crop has not been exploited to a large extent because of perceptions that cassava depletes soils. Recent finding from field studies in the forest/savannah transitional agroecological zone of Ghana indicates that when integ...

  16. Molecular Evidence for the Association of a Strain of Uganda Variant of East African Cassava Mosaic Virus to Symptom Severity in Cassava (Manihot esculenta Crantz) Fields in Togo

    OpenAIRE

    K. D. Adjata; Muller, E; Peterschmitt, M.; Traore, O; Y. M.D. Gumedzoe

    2009-01-01

    Problem statement: This study was carried out to demonstrate that the severity of Cassava Mosaic Disease (CMD) in Togo, is not only influenced by synergism between cassava Begomoviruses in presence, but essentially by recombination between the different Begomoviruses infecting cassava. Approach: Foliar samples presenting typical biological features of Begomoviruses infection were collected from cassava and wild infected plants from different regions of Togo and analysed by PCR targeting the C...

  17. Natural variation in expression of genes associated with biosynthesis and accumulation in cassava (Manihot esculenta Crantz) storage root

    Science.gov (United States)

    Several groups have reported on massive accumulation of total carotenoids in cassava storage root (CSR). Naturally occurring color variation associated with carotenoid accumulation was observed in cassava (Manihot esculenta Crantz) storage root of landraces from Amazon. Here carotenoid profiles from...

  18. Cloning of a peroxidase gene from cassava with potential as a molecular marker for resistance to bacterial blight

    OpenAIRE

    Luiz Filipe Pereira; Goodwin, Paul H.; Larry Erickson

    2003-01-01

    Cassava bacterial blight (CBB), caused by Xanthomonas axonopodis pv. manihotis, is considered one of the most important bacterial diseases of cassava (Manihot esculenta Crantz). In order to characterize the cassava genes involved in resistance to this disease, a genomic clone of a cationic peroxidase gene, MEPX1, was isolated by PCR from cassava cultivar MCOL 22. The DNA sequence of MEPX1 showed high homology with other plant peroxidase genes and contained a large intron typical of peroxidase...

  19. Transcriptome Analysis Using a High-Density Oligomicroarray under Drought Stress in Various Genotypes of Cassava: An Important Tropical Crop

    OpenAIRE

    Utsumi, Yoshinori; Tanaka, Maho; Morosawa, Taeko; Kurotani, Atsushi; Yoshida, Takuhiro; Mochida, Keiichi; Matsui, Akihiro; Umemura, Yoshimi; Ishitani, Manabu; Shinozaki, Kazuo; Sakurai, Tetsuya; Seki, Motoaki

    2012-01-01

    Cassava is an important crop that provides food security and income generation in many tropical countries and is known for its adaptability to various environmental conditions. Despite its global importance, the development of cassava microarray tools has not been well established. Here, we describe the development of a 60-mer oligonucleotide Agilent microarray representing ∼20 000 cassava genes and how it can be applied to expression profiling under drought stress using three cassava genotyp...

  20. RESOURCE UTILIZATION BEHAVIOUR OF CASSAVA PRODUCERS IN EPE AREA OF LAGOS STATE: STOCHASTIC FRONTIER PRODUCTION FUNCTION APPROACH

    OpenAIRE

    Ogunbameru, A.; Okeowo, T.A.

    2013-01-01

    The Stochastic frontier production function was used to assess the technical efficiency of cassava production in Epe Area of Lagos State, Nigeria. Results show that cassava farmers in the study area experienced increasing positive return-to-scale (2.2675. The study also reveals that a significant relationship exists between farm size, labour, planting materials, cost of other input and cassava output in the study area. Cassava farmers with large farmers are found to have higher net farm incom...

  1. Factors Influencing Rural Women Cassava Processors' Intention to Participate in an Agricultural Extension Education Program. Summary of Research 80.

    Science.gov (United States)

    Ojomo, Christian O.; McCaslin, N. L.

    A study examined factors influencing female cassava processors' intentions regarding participation in an extension education program on cassava processing in rural Nigeria. Interviews were conducted with 224 women who were purposely selected from areas of zone 3 of Ondo State, Nigeria, which has large concentrations of cassava processors.…

  2. Assessing the potential of biofortified cassava for improving indices of vitamin A status: Update on human studies

    Science.gov (United States)

    Cassava usually contains essentially no beta-carotene (BC). However, cassava is being bred to increase its BC content. Our objective was to test how effective biofortified cassava is at increasing serum BC and vitamin A (VA) concentrations in healthy adult women. Ten American women participated in ...

  3. Violet diode laser-induced chlorophyll fluorescence: a tool for assessing mosaic disease severity in cassava (Manihot esculenta Crantz) cultivars.

    Science.gov (United States)

    Anderson, Benjamin; Eghan, Moses J; Asare-Bediako, Elvis; Buah-Bassuah, Paul K

    2012-01-01

    Violet diode laser-induced chlorophyll fluorescence was used in agronomical assessment (disease severity and average yield per plant). Because cassava (Manihot esculenta Crantz) is of economic importance, improved cultivars with various levels of affinity for cassava mosaic disease were investigated. Fluorescence data correlated with cassava mosaic disease severity levels and with the average yield per plant.

  4. Why mosaic? Gene expression profiling of African cassava mosaic virus-infected cassava reveals the effect of chlorophyll degradation on symptom development.

    Science.gov (United States)

    Liu, Jiao; Yang, Jun; Bi, Huiping; Zhang, Peng

    2014-02-01

    Cassava mosaic disease, caused by cassava begomoviruses, is the most serious disease for cassava in Africa. However, the pathogenesis of this disease is poorly understood. We employed high throughput digital gene expression profiling based on the Illumina Solexa sequencing technology to investigate the global transcriptional response of cassava to African cassava mosaic virus infection. We found that 3,210 genes were differentially expressed in virus-infected cassava leaves. Gene ontology term and Kyoto Encyclopedia of Genes and Genomes pathway analysis indicated that genes implicated in photosynthesis were most affected, consistent with the chlorotic symptoms observed in infected leaves. The upregulation of chlorophyll degradation genes, including the genes encoding chlorophyllase, pheophytinase, and pheophorbide a oxygenase, and downregulation of genes encoding the major apoproteins in light-harvesting complex II were confirmed by qRT-PCR. These findings, together with the reduction of chlorophyll b content and fewer grana stacks in the infected leaf cells, reveal that the degradation of chlorophyll plays an important role in African cassava mosaic virus symptom development. This study will provide a road map for future investigations into viral pathogenesis.

  5. Complete genome sequencing of two causative viruses of cassava mosaic disease in Ghana.

    Science.gov (United States)

    Oteng-Frimpong, R; Levy, Y; Torkpo, S K; Danquah, E Y; Offei, S K; Gafni, Y

    2012-01-01

    Cassava mosaic disease (CMV), caused by one or a combination of cassava mosaic geminiviruses, is ranked among the most important constraints to profitable and efficient production of cassava. Effective control measures require in-depth knowledge of the viral causative agent. Using rolling-circle amplification and unique enzymes, the full genome of two species of cassava mosaic geminivirus isolated from infected cassava plants in Ghana were cloned into pCambia 1300 and pET-28b. The sequences of the genome were determined on an ABI sequencer and a pairwise comparison was performed with other cassava-infecting geminiviruses from different countries. It was revealed that cassava grown in Ghana is attacked by two species of geminivirus in either single or mixed infections. These are the African cassava mosaic virus (ACMV) and the East African cassava mosaic virus (EACMV)-like, with high sequence similarity of 94% and 80%, respectively, between the DNA-A and DNA-B components of each virus, and 66% and 41% similarity of the common region (CR) (for A and B accordingly). The DNA-A of ACMV and EACMV-like contained 2781 and 2800 nucleotides, respectively, while their DNA-B components had 2725 and 2734 nucleotides, respectively. ACMV DNA-A was over 97% similar to those of other ACMVs from the continent. In contrast, EACMV-like DNA-A was over 98% similar to the isolates from Cameroon and other West African countries, and less than 88% similar to other EACMV species. Thus ACMV and EACMV-like were named African cassava mosaic virus-Ghana and East African cassava mosaic Cameroon virus-Ghana. Computer analysis revealed that their genome arrangement follows the typical old world bipartite begomovirus genome. The association of these two species and their interaction might account for the severe symptoms observed on infected plants in the field and in the greenhouse.

  6. Analysis of cassava (Manihot esculenta) ESTs: A tool for the discovery of genes

    International Nuclear Information System (INIS)

    Cassava (Manihot esculenta) is the main source of calories for more than 1,000 millions of people around the world and has been consolidated as the fourth most important crop after rice, corn and wheat. Cassava is considered tolerant to abiotic and biotic stress conditions; nevertheless these characteristics are mainly present in non-commercial varieties. Genetic breeding strategies represent an alternative to introduce the desirable characteristics into commercial varieties. A fundamental step for accelerating the genetic breeding process in cassava requires the identification of genes associated to these characteristics. One rapid strategy for the identification of genes is the possibility to have a large collection of ESTs (expressed sequence tag). In this study, a complete analysis of cassava ESTs was done. The cassava ESTs represent 80,459 sequences which were assembled in a set of 29,231 unique genes (unigen), comprising 10,945 contigs and 18,286 singletones. These 29,231 unique genes represent about 80% of the genes of the cassava's genome. Between 5% and 10% of the unigenes of cassava not show similarity to any sequences present in the NCBI database and could be consider as cassava specific genes. a functional category was assigned to a group of sequences of the unigen set (29%) following the Gene Ontology Vocabulary. the molecular function component was the best represented with 43% of the sequences, followed by the biological process component (38%) and finally the cellular component with 19%. in the cassava ESTs collection, 3,709 microsatellites were identified and they could be used as molecular markers. this study represents an important contribution to the knowledge of the functional genomic structure of cassava and constitutes an important tool for the identification of genes associated to agricultural characteristics of interest that could be employed in cassava breeding programs.

  7. Improvement of cassava cooking quality through mutation breeding

    International Nuclear Information System (INIS)

    Many high-yielding cassava varieties do not have the desired cooking quality. The objective of this project was to induce mutations to produce varieties with improved cooking quality while maintaining the disease-resistance and high-yielding characteristics. A cassava mutant (ISU-W) was obtained after irradiation of a variety from IITA with gamma rays and selection. Cuttings of the mutant were grown for 12 months in a field trial and investigated for tuber yield and cooking quality. Pest and disease incidence were monitored during the entire growth period. The results showed that the mutant retained the high-yield and disease resistant characters of the parent, and had improved cooking quality based on increased smoothness, mealiness and elasticity of the flour. (author). 7 refs, 5 tabs

  8. NOTE - Genetic variability among cassava accessions based on SSR markers

    Directory of Open Access Journals (Sweden)

    Márcia de Nazaré Oliveira Ribeiro

    2011-01-01

    Full Text Available The aim of this study was to characterize and estimate the genetic similarity among 93 cassava accessions. The DNAamplification was performed with 14 microsatellite primers. The amplification products were separated by a polyacrylamide gelelectrophoresis, showing a polymorphism formation, through which the accessions were discriminated against. The genetic similarityamong accessions of cassava was estimated by the Dice coefficient. Cluster analysis was carried out using the UPGMA method. Thepolymorphic primers amplified a total of 26 alleles with 2-4 alleles per loci. The genetic similarity ranged from 0.16 to 0.96. Theaverage values for observed and expected heterozygosity were 0.18 and 0.46, respectively. Twenty genetic similarity clusters weredetermined, demonstrating diversity among accessions, suggesting the possibility of heterotic hybrid generation.

  9. Antioxidant Phenolic Compounds of Cassava (Manihot esculenta from Hainan

    Directory of Open Access Journals (Sweden)

    Haofu Dai

    2011-12-01

    Full Text Available An activity-directed fractionation and purification process was used to isolate antioxidant components from cassava stems produced in Hainan. The ethyl acetate and n-butanol fractions showed greater DPPH˙and ABTS·+ scavenging activities than other fractions. The ethyl acetate fraction was subjected to column chromatography, to yield ten phenolic compounds: Coniferaldehyde (1, isovanillin (2, 6-deoxyjacareubin (3, scopoletin (4, syringaldehyde (5, pinoresinol (6, p-coumaric acid (7, ficusol (8, balanophonin (9 and ethamivan (10, which possess significant antioxidant activities. The relative order of DPPH· scavenging capacity for these compounds was ascorbic acid (reference > 6 > 1 > 8 > 10 > 9 > 3 > 4 > 7 > 5 > 2, and that of ABTS·+ scavenging capacity was 5 > 7 > 1 > 10 > 4 > 6 > 8 > 2 > Trolox (reference compound > 3 > 9. The results showed that these phenolic compounds contributed to the antioxidant activity of cassava.

  10. Antioxidant phenolic compounds of cassava (Manihot esculenta) from Hainan.

    Science.gov (United States)

    Yi, Bo; Hu, Lifei; Mei, Wenli; Zhou, Kaibing; Wang, Hui; Luo, Ying; Wei, Xiaoyi; Dai, Haofu

    2011-12-07

    An activity-directed fractionation and purification process was used to isolate antioxidant components from cassava stems produced in Hainan. The ethyl acetate and n-butanol fractions showed greater DPPH˙and ABTS·+ scavenging activities than other fractions. The ethyl acetate fraction was subjected to column chromatography, to yield ten phenolic compounds: Coniferaldehyde (1), isovanillin (2), 6-deoxyjacareubin (3), scopoletin (4), syringaldehyde (5), pinoresinol (6), p-coumaric acid (7), ficusol (8), balanophonin (9) and ethamivan (10), which possess significant antioxidant activities. The relative order of DPPH· scavenging capacity for these compounds was ascorbic acid (reference) > 6 > 1 > 8 > 10 > 9 > 3 > 4 > 7 > 5 > 2, and that of ABTS·+ scavenging capacity was 5 > 7 > 1 > 10 > 4 > 6 > 8 > 2 > Trolox (reference compound) > 3 > 9. The results showed that these phenolic compounds contributed to the antioxidant activity of cassava.

  11. Fermentation protocols for the nutritive upgrading and detoxification of cassava

    International Nuclear Information System (INIS)

    The paper outlines common recommended procedures to be followed by those working in the area to facilitate the comparison of the results obtained. The report contains the wide spectrum of recommendations towards (i) the methods of preliminary preparation fo the cassava root for further fermentation reprocessing; (ii) optimization of the environmental parameters of the fermentation process, including pretreatment manipulations, moisture content, pH, temperature, aeration, form/size of inoculum, etc., (iii) optimization of the incubation time and selecting the fermentation systems and (iv) the analytical and quality control aspects. Some problems connected with the use of exogenous nitrogen sources to enhance the protein/aminoacid synthesis (supplementation of the fermenting mash with inorganic nitrogen salts, yeast extracts, indigenous sources of vegetable/animal nature, nitrogen fixing bacteria, etc.) are discussed and considered depending on their cost and effectiveness. Concerns about the safety aspects possibly arising from the alteration of the traditional practice of the cassava fermentation are also reported. (author)

  12. Study of cassava starch enzymatic modification for maltodextrins obtention

    OpenAIRE

    Miguel Angel Díaz; María Isabel Filella; Velásquez, Mario E.

    2012-01-01

    It was pretended to investigate the effect of the most relevant variables in cassava starch enzymatic hydrolysis process, on laboratory scale, to determine appropriate industrial conditions for the obtention of different kinds of maltodextrins. An a-Amylase enzyme, from genetically modified strain of Bacillus lichenijormis, was used to hydrolize the starch. Once the variables were chosen, an experimental fractioned factorial design was established with two levels. The Dextrose Equivalent (DE)...

  13. Antioxidant Phenolic Compounds of Cassava (Manihot esculenta) from Hainan

    OpenAIRE

    Haofu Dai; Ying Luo; Hui Wang; Kaibing Zhou; Wenli Mei; Bo Yi; Lifei Hu; Xiaoyi Wei

    2011-01-01

    An activity-directed fractionation and purification process was used to isolate antioxidant components from cassava stems produced in Hainan. The ethyl acetate and n-butanol fractions showed greater DPPH˙and ABTS·+ scavenging activities than other fractions. The ethyl acetate fraction was subjected to column chromatography, to yield ten phenolic compounds: Coniferaldehyde (1), isovanillin (2), 6-deoxyjacareubin (3), scopoletin (4), syringaldehyde (5), pinoresinol (6), p-coumaric acid (7), fic...

  14. Cassava starch effluent treatment with concomitant SCP production.

    Science.gov (United States)

    Manilal, V B; Narayanan, C S; Balagopalan, C

    1991-03-01

    Yeasts and yeast-like organisms were chosen for the aerobic treatment of cassava starch factory effluent. A mixed culture of Candida utills and Endomycopsis fibuliger efficiently and rapidly utilized both starch and free sugars. After 28 h fermentation the protein content of the biomass was 22% (w/w), which remained unchanged during the remainder of the fermentation (60 h). This treatment removed 94% of the COD and 91% of the BOD.

  15. Gene-based Microsatellites for Cassava (Manihot esculenta Crantz): Prevalence, Polymorphisms, and Cross-taxa Utility

    Science.gov (United States)

    Cassava (Manihot esculenta Crantz), a starchy root crop grown in tropical and subtropical climates, is the sixth most important crop in the world after wheat, rice, maize, potato and barley. The repertoire of simple sequence repeat (SSR) markers for cassava is limited and warrants a need for a large...

  16. Cassava and soil fertility in intensifying smallholder farming systems of East Africa

    NARCIS (Netherlands)

    Fermont, van A.M.

    2009-01-01

    Keywords: Cost-benefits, Crop management, Farming systems, Fertilizer, Food security, Generalizations, Income, Labour, Land pressure, Niche, Rainfall, Sub-Saharan Africa, System analysis, Yield gap. Cassava is an important crop in Africa. This thesis focuses on cassava production in the mid altitud

  17. Sustaining World Food Security with Improved Cassava Processing Technology: The Nigeria Experience

    Directory of Open Access Journals (Sweden)

    Peter O. Kolawole

    2010-11-01

    Full Text Available Cassava is a very important food crop that is capable of providing food security. However, a lot of problems prevent the development and use of modern equipment for its production. Most of the cassava produced still comes from peasant farmers who depend on manual tools for their field operations and these farmers have made Nigeria the world’s largest producer of the crop. An increase in production of cassava to sustain the world food security needs improved machinery to allow its continuous cultivation and processing. Reasons for the low success recorded in the mechanization of cassava harvesting and processing were traced, and the attempts that have been made in the recent past by various engineers in Nigeria researching towards achieving mechanized harvesting and processing of cassava are well explained. The machinery required for cassava production in Africa, the development of new machines, and the need for more research and development in harvesting and processing machineries, which can reduce poverty worldwide and make food available and accessible for all, are also discussed. Research efforts made and the challenges facing the engineers, farmers, scientists and food processors towards achieving mechanical harvesting and processing of cassava are presented. Breeding a cassava variety with a regular shape for easy mechanization is one solution that could help the engineers worldwide.

  18. Closing the cassava yield gap: an analysis from small-holder farms in East Africa

    NARCIS (Netherlands)

    Fermont, van A.M.; Asten, van P.J.A.; Tittonell, P.A.; Wijk, van M.T.; Giller, K.E.

    2009-01-01

    Cassava yields in Africa are small and it remains unclear which factors most limit yields. Using a series of farm surveys and on-farm and on-station trials in Uganda and western Kenya, we evaluated the importance of abiotic, biotic and associated crop management constraints for cassava production in

  19. Cloning and characterization of a tuberous root-specific promoter from cassava (Manihot esculenta Crantz)

    NARCIS (Netherlands)

    Koehorst-van Putten, H.J.J.; Wolters, A.M.A.; Pereira-Bertram, I.J.; Berg, H.; Krol, van der A.R.; Visser, R.G.F.

    2012-01-01

    In order to obtain a tuberous root-specific promoter to be used in the transformation of cassava, a 1,728 bp sequence containing the cassava granule-bound starch synthase (GBSSI) promoter was isolated. The sequence proved to contain light- and sugar-responsive cis elements. Part of this sequence (1,

  20. Infochemical use by predatory mites of the cassava green mite in a multitrophic context

    NARCIS (Netherlands)

    Gnanvossou, D.

    2002-01-01

    This thesis describes research on multitrophic interactions in a system consisting of (1) cassava plants ( Manihot esculenta ), (2) three herbivorous mites, i.e. the cassava green mite Mononychellus tanajoa, the red spider mite Oligonychus gossypii and the two-spotted spider mite Tetranychus urticae

  1. Isolation and characterisation of starch biosynthesis genes from cassava (Manihot esculenta Crantz).

    NARCIS (Netherlands)

    Munyikwa, T.R.I.

    1997-01-01

    Cassava (Manihot esculenta Crantz) is a tropical crop grown for its starchy thickened roots, mainly by peasant farmers, in the tropics, for whom it is a staple food. There is an increasing demand for the use of cassava in processed food and feed products, and in the paper and textile industries amon

  2. Analysis of heterogeneity of Copia-like retrotransposons in the genome of cassava (Manihot esculenta Crantz).

    Science.gov (United States)

    Gbadegesin, Micheal A; Beeching, John R

    2011-12-20

    Retrotransposons are ubiquitous in eukaryotic genomes and now proving to be useful genetic tools for genetic diversity and phylogenetic analyses, especially in plants. In order to assess the diversity of Ty1/Copia-like retrotransposons of cassava, we used PCR primers anchored on the conserved domains of reverse transcriptases (RTs) to amplify cassava Ty1/Copia-like RT. The PCR product was cloned and sequenced. Sequences analysis of the clones revealed the presence of 69 families of Ty1/Copia-like retrotransposon in the genome of cassava. Comparative analyses of the predicted amino acid sequences of these clones with those of other plants showed that retroelements of this class are very heterogeneous in cassava. Cassava is widely grown for its edible roots in the tropical and subtropical regions of the world. Cassava roots, though poor in protein, are rich in starch (makes up about 80% of the dry matter), vitamin C, carotenes, calcium and potassium. It has a great commercial importance as a source of starch and starch based products. Realizing the importance of cassava, it stands out as a crop to benefit from biotechnology development. Heterogeneity of Mecops (Manihot esculenta copia-like Retrotransposons) showed that they may be useful for genetic diversity and phylogenetic analyses of cassava germplasm.

  3. Optimization of biohydrogen and methane recovery within a cassava ethanol wastewater/waste integrated management system

    DEFF Research Database (Denmark)

    Wang, Wen; Xie, Li; Luo, Gang;

    2012-01-01

    Thermophilic co-fermentation of cassava stillage (CS) and cassava excess sludge (CES) were investigated for hydrogen and methane production. The highest hydrogen yield (37.1 ml/g-total-VS added) was obtained at VSCS/VSCES of 7:1, 17% higher than that with CS digestion alone. The CES recycle...

  4. Computational identification of microRNAs and their targets in cassava (Manihot esculenta Crantz.).

    Science.gov (United States)

    Patanun, Onsaya; Lertpanyasampatha, Manassawe; Sojikul, Punchapat; Viboonjun, Unchera; Narangajavana, Jarunya

    2013-03-01

    MicroRNAs (miRNAs) are a newly discovered class of noncoding endogenous small RNAs involved in plant growth and development as well as response to environmental stresses. miRNAs have been extensively studied in various plant species, however, only few information are available in cassava, which serves as one of the staple food crops, a biofuel crop, animal feed and industrial raw materials. In this study, the 169 potential cassava miRNAs belonging to 34 miRNA families were identified by computational approach. Interestingly, mes-miR319b was represented as the first putative mirtron demonstrated in cassava. A total of 15 miRNA clusters involving 7 miRNA families, and 12 pairs of sense and antisense strand cassava miRNAs belonging to six different miRNA families were discovered. Prediction of potential miRNA target genes revealed their functions involved in various important plant biological processes. The cis-regulatory elements relevant to drought stress and plant hormone response were identified in the promoter regions of those miRNA genes. The results provided a foundation for further investigation of the functional role of known transcription factors in the regulation of cassava miRNAs. The better understandings of the complexity of miRNA-mediated genes network in cassava would unravel cassava complex biology in storage root development and in coping with environmental stresses, thus providing more insights for future exploitation in cassava improvement.

  5. Genetic mapping using genotyping-by-sequencing in the clonally-propagated cassava

    Science.gov (United States)

    Cassava (Manihot esculenta L.) is one of the most important food crops in the tropics, but yields are far below their potential. The gene-pool of cassava contains natural genetic diversity relevant to many important breeding goals, but breeding progress has been slow, partly due to insufficient geno...

  6. Exploring the potential of cassava in promoting agricultural growth in Nigeria

    Directory of Open Access Journals (Sweden)

    Sanzidur Rahman

    2016-05-01

    Full Text Available Cassava is one of the major food crops in Nigeria, with multiple uses from human consumption to industrial applications. This study explores the potential of cassava in Nigerian agriculture based on a review of cassava development policies; performs a trend analysis of the cultivation area, production, productivity, and real price of cassava and other competing crops for the period 1961–2013; identifies the sources of growth in production; and examines the production constraints at the local level based on a survey of 315 farmers/processors and 105 marketers from Delta State. The results revealed that several policies and programmes were implemented to develop the cassava sector with mixed outcomes. Although cassava productivity grew at 1.5% per annum (p.a. during the post-structural adjustment programme period (1993–2013, its real price declined at a rate of 3.5% p.a. The effect of yield is the main source of growth in production, contributing 76.4% of the total growth followed by the area effect (28.2%. The cassava sector is constrained by inadequate market infrastructure, processing facilities, and lack of information and unstable prices at the local level. The widespread diffusion of improved tropical manioc selection technologies and investments in market and marketing infrastructure, processing technologies, irrigation/water provision and information dissemination are recommended to enhance the potential of the cassava sector to support agricultural growth in Nigeria.

  7. Optimization of enzymatic hydrolysis of cassava to obtain fermentable sugars

    Institute of Scientific and Technical Information of China (English)

    Renata M. COLLARES; Luiza V. S. MIKLASEVICIUS; Mariana M. BASSACO; Nina P. G. SALAU; Marcio A. MAZUTTI; Dilson A. BISOGNIN; Lisiane M. TERRA

    2012-01-01

    This work evaluates the enzymatic hydrolysis of starch from cassava using pectinase,α-amylase,and amyloglucosidase.A central composite rotational design (CCRD) was carried out to evaluate the effects of amyloglucosidase,pectinase,reaction time,and solid to liquid ratio.All the experiments were carried out in a bioreactor with working volume of 2 L.Approximately 98% efficiency hydrolysis was obtained,resulting in a concentration of total reducing sugar released of 160 g/L.It was concluded that pectinase improved the hydrolysis of starch from cassava.Reaction time was found to be significant until 7 h of reaction.A solid to liquid ratio of 1.0 was considered suitable for hydrolysis of starch from cassava.Amyloglucosidase was a significant variable in the process:after its addition to the reaction media,a 30%-50% increase in the amount of total reducing sugar released was observed.At optimal conditions the maximum productivity obtained was 22.9 g/(L·h).

  8. Classification of cassava genotypes based on qualitative and quantitative data.

    Science.gov (United States)

    Oliveira, E J; Oliveira Filho, O S; Santos, V S

    2015-02-02

    We evaluated the genetic variation of cassava accessions based on qualitative (binomial and multicategorical) and quantitative traits (continuous). We characterized 95 accessions obtained from the Cassava Germplasm Bank of Embrapa Mandioca e Fruticultura; we evaluated these accessions for 13 continuous, 10 binary, and 25 multicategorical traits. First, we analyzed the accessions based only on quantitative traits; next, we conducted joint analysis (qualitative and quantitative traits) based on the Ward-MLM method, which performs clustering in two stages. According to the pseudo-F, pseudo-t2, and maximum likelihood criteria, we identified five and four groups based on quantitative trait and joint analysis, respectively. The smaller number of groups identified based on joint analysis may be related to the nature of the data. On the other hand, quantitative data are more subject to environmental effects in the phenotype expression; this results in the absence of genetic differences, thereby contributing to greater differentiation among accessions. For most of the accessions, the maximum probability of classification was >0.90, independent of the trait analyzed, indicating a good fit of the clustering method. Differences in clustering according to the type of data implied that analysis of quantitative and qualitative traits in cassava germplasm might explore different genomic regions. On the other hand, when joint analysis was used, the means and ranges of genetic distances were high, indicating that the Ward-MLM method is very useful for clustering genotypes when there are several phenotypic traits, such as in the case of genetic resources and breeding programs.

  9. Stability of cassava flour-based food bars

    Directory of Open Access Journals (Sweden)

    Erica Caroline da Silva

    2013-03-01

    Full Text Available The consumption of Brazilian cassava has been reduced due to a lack of adjustment to the modern lifestyle. To reverse this trend, new products could be developed specifically targeted to high-value niche markets. Cereal bars stand out as fast food high in nutritional value. A bar formula mimicking cereal bars was prepared using a mixture of Brazilian cassava flour, hydrogenated vegetable fat, dried bananas, ground cashew nuts, and glucose syrup. After being pressed, the bars were dried for 1 hour at 65 °C, packaged in films, and stored under ambient conditions. Its stability was continuously monitored for 210 days in order to ensure its safety and enable its introduction to the market. Texture loss was observed in the packed bars after 90 days of storage, but the sensory characteristics allowed the testers to perceive this tendency after only 30 days of storage. However, chemical, physical, and microbial analyses confirmed that the bars were safe for consumption for 180 days. The results showed that a 45 g cassava flour-based bar enriched with nuts and dried fruits can meet 6% of the recommended daily fiber intake with a caloric value between that of the common cereal bar and that of an energy bar. Adapting the formula with ingredients (fruits, nuts from different regions of Brazil may add value to this traditional product as a fast food.

  10. Effect of plant-biostimulant on cassava initial growth

    Directory of Open Access Journals (Sweden)

    João Emílio de Souza Magalhães

    2016-04-01

    Full Text Available ABSTRACT Biostimulants are complex substances that promote hormonal balance in plants, favor the genetic potential expression, and enhance growth of shoots and root system. The use of these plant growth promoters in crops can increase quantitatively and qualitatively crop production. Therefore, the aim of this study was to evaluate the effect of a commercial biostimulant on the initial growth of cassava. The experiment was arranged in a 2 x 5 factorial design, corresponding to two cassava cultivars (Cacau-UFV and Coimbra and five biostimulant concentrations (0, 4, 8, 12 and 16 mL L-1. At 90 days after planting, the characteristics leaf area, plant height, stem diameter, leaf number, total dry matter and dry matter of roots, stems and leaves were evaluated. The biostimulant promoted linear increases in plant height, leaf number, leaf area, total dry matter, dry matter of stems, leaves and roots. The cultivar Cacau-UFV had a higher growth rate than the cultivar Coimbra. The growth promoter stimulated the early growth of the cassava crop.

  11. Cassava Market Participation Decisions of Producing Households in Africa

    Directory of Open Access Journals (Sweden)

    Enete, AA.

    2009-01-01

    Full Text Available Cassava is a basic staple and a major source of farm income for the people of sub-Saharan Africa. Efficiency in cassava marketing therefore becomes a very important determinant of both consumer's living cost and producer's income. At the farmer's level, which is the beginning of the marketing chain, food must produced in reasonable quantity to attract enough market participants that will make for efficient distribution. The use of food price policy to stimulate short-run marketed surplus of producing households has often been questioned. This is because some households are deficit producers who purchase crops they also produce. Increasing producer prices will therefore have adverse distributional effects on food buying, while bypassing autarkic households. An alternative would therefore be to find non-price strategic variables that motivate farm households to participate in commodity markets. This is the objective of this paper. The paper is based on primary data collected within the framework by the collaborative study of cassava in Africa (COSCA. Good market access conditions, improved market information especially on prices, the production of granules instead of dried roots or pastes increased market participation for sellers, while rising grain prices, younger and less educated heads of households encouraged participation for buyers.

  12. Characters related to higher starch accumulation in cassava storage roots.

    Science.gov (United States)

    Li, You-Zhi; Zhao, Jian-Yu; Wu, San-Min; Fan, Xian-Wei; Luo, Xing-Lu; Chen, Bao-Shan

    2016-01-01

    Cassava (Manihot esculenta) is valued mainly for high content starch in its roots. Our understanding of mechanisms promoting high starch accumulation in the roots is, however, still very limited. Two field-grown cassava cultivars, Huanan 124(H124) with low root starch and Fuxuan 01(F01) with high root starch, were characterised comparatively at four main growth stages. Changes in key sugars in the leaves, stems and roots seemed not to be strongly associated with the final amount of starch accumulated in the roots. However, when compared with H124, F01 exhibited a more compact arrangement of xylem vascular bundles in the leaf axils, much less callose around the phloem sieve plates in the stems, higher starch synthesis-related enzymatic activity but lower amylase activity in the roots, more significantly up-regulated expression of related genes, and a much higher stem flow rate (SFR). In conclusion, higher starch accumulation in the roots results from the concurrent effects of powerful stem transport capacity highlighted by higher SFR, high starch synthesis but low starch degradation in the roots, and high expression of sugar transporter genes in the stems. A model of high starch accumulation in cassava roots was therefore proposed and discussed.

  13. Emergy analysis of cassava-based fuel ethanol in China

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Hui; Chen, Li; Yan, Zongcheng; Wang, Honglin [School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, Guangdong 510640 (China)

    2011-01-15

    Emergy analysis considers both energy quality and energy used in the past, and compensates for the inability of money to value non-market inputs in an objective manner. Its common unit allows all resources to be compared on a fair basis. As feedstock for fuel ethanol, cassava has some advantages over other feedstocks. The production system of cassava-based fuel ethanol (CFE) was evaluated by emergy analysis. The emergy indices for the system of cassava-based fuel ethanol (CFE) are as follows: transformity is 1.10 E + 5 sej/J, EYR is 1.07, ELR is 2.55, RER is 0.28, and ESI is 0.42. Compared with the emergy indices of wheat ethanol and corn ethanol, CFE is the most sustainable. CFE is a good alternative to substitute for oil in China. Non-renewable purchased emergy accounts for 71.15% of the whole input emergy. The dependence on non-renewable energy increases environmental degradation, making the system less sustainable relative to systems more dependent on renewable energies. For sustainable development, it is vital to reduce the consumption of non-renewable energy in the production of CFE. (author)

  14. Emergy analysis of cassava-based fuel ethanol in China

    International Nuclear Information System (INIS)

    Emergy analysis considers both energy quality and energy used in the past, and compensates for the inability of money to value non-market inputs in an objective manner. Its common unit allows all resources to be compared on a fair basis. As feedstock for fuel ethanol, cassava has some advantages over other feedstocks. The production system of cassava-based fuel ethanol (CFE) was evaluated by emergy analysis. The emergy indices for the system of cassava-based fuel ethanol (CFE) are as follows: transformity is 1.10 E + 5 sej/J, EYR is 1.07, ELR is 2.55, RER is 0.28, and ESI is 0.42. Compared with the emergy indices of wheat ethanol and corn ethanol, CFE is the most sustainable. CFE is a good alternative to substitute for oil in China. Non-renewable purchased emergy accounts for 71.15% of the whole input emergy. The dependence on non-renewable energy increases environmental degradation, making the system less sustainable relative to systems more dependent on renewable energies. For sustainable development, it is vital to reduce the consumption of non-renewable energy in the production of CFE. (author)

  15. Characters related to higher starch accumulation in cassava storage roots.

    Science.gov (United States)

    Li, You-Zhi; Zhao, Jian-Yu; Wu, San-Min; Fan, Xian-Wei; Luo, Xing-Lu; Chen, Bao-Shan

    2016-01-01

    Cassava (Manihot esculenta) is valued mainly for high content starch in its roots. Our understanding of mechanisms promoting high starch accumulation in the roots is, however, still very limited. Two field-grown cassava cultivars, Huanan 124(H124) with low root starch and Fuxuan 01(F01) with high root starch, were characterised comparatively at four main growth stages. Changes in key sugars in the leaves, stems and roots seemed not to be strongly associated with the final amount of starch accumulated in the roots. However, when compared with H124, F01 exhibited a more compact arrangement of xylem vascular bundles in the leaf axils, much less callose around the phloem sieve plates in the stems, higher starch synthesis-related enzymatic activity but lower amylase activity in the roots, more significantly up-regulated expression of related genes, and a much higher stem flow rate (SFR). In conclusion, higher starch accumulation in the roots results from the concurrent effects of powerful stem transport capacity highlighted by higher SFR, high starch synthesis but low starch degradation in the roots, and high expression of sugar transporter genes in the stems. A model of high starch accumulation in cassava roots was therefore proposed and discussed. PMID:26892156

  16. Characterization of different cassava samples by nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Cassava root (Manihot esculenta Crantz) is grown in all Brazilian states, being an important product in the diet of Brazilians. For many families of the North and Northeast states, it may represent the main energy source. The cassava root flour has high levels of starch, in addition to containing fiber, lipids and some minerals. There is, however, great genetic variability, which results in differentiation in its chemical composition and structural aspect. Motivated by the economic, nutritional and pharmacological importance of this product, this work is aimed at characterizing six cassava flour samples by NMR spectroscopy. The spectra revealed the main chemical groups. Furthermore, the results confirmed differences on chemical and structural aspect of the samples. For instance, the F1 sample is richer in carbohydrates, while the F4 sample has higher proportion of glycolipids, the F2 sample has higher amylose content and the F6 sample exhibits a greater diversity of glycolipid types. Regarding the molecular structure, the NMR spectra indicated that the F1 sample is more organized at the molecular level, while the F3 and F5 samples are similar in amorphicity and in the molecular packing. (author)

  17. The sustainability of cassava-based bioethanol production in southern Mali

    DEFF Research Database (Denmark)

    Rasmussen, Kjeld; Birch-Thomsen, Torben; Bruun, Thilde Bech;

    2015-01-01

    of cassava-based bioethanol production in southern Mali, assessing its environmental, economic and social sustainability. Results demonstrate that environmental sustainability of cassava-based bioethanol production depends on the ‘baseline’ chosen: Compared to the situation before the decline in cotton...... production 10 years ago, the carbon stocks will increase. However, if compared to the current situation, where considerable carbon stocks have accumulated in fallow fields, the loss of carbon will be substantial. Increased cassava production will create greater incomes and better temporal distribution...... of labour input. Analysis of the significance of current cassava production for food security shows that bioethanol production should be based on the attiéké variety of cassava, thereby avoiding interference with the important role of the bonouma in assuring food security in northern Mali. The key factor...

  18. Development of starter culture for improved processing of Lafun, an African fermented cassava food product

    DEFF Research Database (Denmark)

    Padonou, S.W.; Nielsen, Dennis Sandris; Akissoe, N.H.;

    2010-01-01

    AIMS: To select appropriate micro-organisms to be used as starter culture for reliable and reproducible fermentation of Lafun. METHODS AND RESULTS: A total of 22 cultures consisting of yeast, lactic acid bacteria (LAB) and Bacillus cereus strains predominant in traditionally fermented cassava...... in different combinations as mixed starter cultures to ferment submerged cassava roots. Saccharomyces cerevisiae, inoculated singly or combined with B. cereus, gave the softest cassava root after 48 h of fermentation according to determination of compression profile and stress at fracture. Overall, sensory...... quality testing showed that Lafun obtained from S. cerevisiae-fermented cassava gave the most preferred stiff porridge. Saccharomyces cerevisiae 2Y48P22 showed pectinase production in a model system. CONCLUSIONS: The results suggest that S. cerevisiae 2Y48P22 is the most efficient organism for cassava...

  19. Biorefinery approach for cassava-based industrial wastes: Current status and opportunities.

    Science.gov (United States)

    Zhang, Ming; Xie, Li; Yin, Zhixuan; Khanal, Samir Kumar; Zhou, Qi

    2016-09-01

    Cassava, an important food crop, has been extensively employed as raw materials for various agri-industries to produce starch, bioethanol and other biobased products/chemicals. These cassava-based industries also generate large quantities of wastes/residues, rich in organic matter and suspended solids, and pose significant environmental issues. Their complex biochemical composition with high organic content endows them with a great potential for bioconversion into value-added products via biorefinery thereby providing economic and environmental sustainability to cassava industries. This state-of-the-art review covers the source, composition and characteristics of cassava industrial wastes and residues, and their bioconversion into value-added products, mainly biofuels (ethanol and butanol), biogas, biosurfactant, organic acids and other valuable biochemicals among others. This paper also outlines future perspectives with respect to developing more effective and efficient bioconversion processes for converting the cassava wastes and residues into high-value products. PMID:27117291

  20. Simultaneous saccharification and fermentation of cassava to succinic acid by Escherichia coli NZN111.

    Science.gov (United States)

    Chen, Cuixia; Ding, Shaopeng; Wang, Dezheng; Li, Zhimin; Ye, Qin

    2014-07-01

    In this study, the production of succinic acid from cassava starch and raw cassava instead of glucose by Escherichia coli NZN111 was investigated. During the two-stage fermentation, simultaneous saccharification and fermentation (SSF) was applied in the anaerobic stage. The results showed that both the productivity and specific productivity in the process conducted at 40°C were higher than those in the cultivation conducted at 37°C. The yield of succinic acid based on the amount of added starch reached the highest level 0.86 g/g and cassava starch was almost totally hydrolyzed in the SSF process. With the improved cell density, 127.13 g/L of succinic acid was obtained. When the liquefied crude cassava powder was used directly in SSF, 106.17 g/L of succinic acid was formed. The result showed that crude cassava powder could be another cheap raw material for succinic acid formation. PMID:24787322

  1. Bioconversion of industrial solid waste--cassava bagasse for pullulan production in solid state fermentation.

    Science.gov (United States)

    Sugumaran, K R; Jothi, P; Ponnusami, V

    2014-01-01

    The purpose of the work was to produce commercially important pullulan using industrial solid waste namely cassava bagasse in solid state fermentation and minimize the solid waste disposal problem. First, influence of initial pH on cell morphology and pullulan yield was studied. Effect of various factors like fermentation time, moisture ratio, nitrogen sources and particle size on pullulan yield was investigated. Various supplementary carbon sources (3%, w/w) namely glucose, sucrose, fructose, maltose, mannose and xylose with cassava bagasse was also studied to improve the pullulan yield. After screening the suitable supplement, effect of supplement concentration on pullulan production was investigated. The pullulan from cassava bagasse was characterized by FTIR, (1)H-NMR and (13)C-NMR. Molecular weight of pullulan from cassava bagasse was determined by gel permeation chromatography. Thus, cassava bagasse emerged to be a cheap and novel substrate for pullulan production.

  2. Optimizing The Use of Cassava Plant and its Byproduct as Ruminant Feed

    Directory of Open Access Journals (Sweden)

    Risa Antari

    2009-12-01

    Full Text Available An alternative to overcome the lack of feed is to use local feed resources. Cassava (Manihot utilissima is a tropical plant that grows easily in all types of soil. At the time of harvest, the price is relatively cheap. Cassava has a low nutritive value, especially in crude protein, but it is a potential source of energy. The research to optimize the use of cassava as feed is by enrichment of its nutritional value, production of single cell protein or supplementation with other feed ingredient. Cassava leaves or hay contain high protein level so that it can be used as protein source. However, its utilization is limited by anti nutritive compounds, such as cyanide acid and linamarin. It can be overcome by physical, chemical and biological treatments as detoxification. The use of cassava in livestock feed requires a formulation strategy to obtain the optimal productivity.

  3. Characterisation of Cassava Bagasse and Composites Prepared by Blending with Low-Density Polyethylene

    Directory of Open Access Journals (Sweden)

    Fabiane Oliveira Farias

    2014-12-01

    Full Text Available The main objective of this study was to characterise the cassava bagasse and to evaluate its addition in composites. Two cassava bagasse samples were characterised using physicochemical, thermal and microscopic techniques, and by obtaining their spectra in the mid-infrared region and analysing them by using x-ray diffraction. Utilising sorption isotherms, it was possible to establish the acceptable conditions of temperature and relative humidity for the storage of the cassava bagasse. The incorporation of cassava bagasse in a low-density polyethylene (LDP matrix was positive, increasing the elasticity modulus values from 131.90 for LDP to 186.2 for 70% LDP with 30% SP bagasse. These results were encouraging because cassava bagasse could serve as a structural reinforcement, as well as having environmental advantages for its application in packaging, construction and automotive parts.

  4. Food safety: importance of composition for assessing genetically modified cassava (Manihot esculenta Crantz).

    Science.gov (United States)

    van Rijssen, Fredrika W Jansen; Morris, E Jane; Eloff, Jacobus N

    2013-09-01

    The importance of food composition in safety assessments of genetically modified (GM) food is described for cassava ( Manihot esculenta Crantz) that naturally contains significantly high levels of cyanogenic glycoside (CG) toxicants in roots and leaves. The assessment of the safety of GM cassava would logically require comparison with a non-GM crop with a proven "history of safe use". This study investigates this statement for cassava. A non-GM comparator that qualifies would be a processed product with CG level below the approved maximum level in food and that also satisfies a "worst case" of total dietary consumption. Although acute and chronic toxicity benchmark CG values for humans have been determined, intake data are scarce. Therefore, the non-GM cassava comparator is defined on the "best available knowledge". We consider nutritional values for cassava and conclude that CG residues in food should be a priority topic for research.

  5. Microbiological and Biochemical Characterization of Cassava Retting, a Traditional Lactic Acid Fermentation for Foo-Foo (Cassava Flour) Production

    OpenAIRE

    Brauman, A.; Keleke, S.; Malonga, M.; Miambi, E.; Ampe, F

    1996-01-01

    The overall kinetics of retting, a spontaneous fermentation of cassava roots performed in central Africa, was investigated in terms of microbial-population evolution and biochemical and physicochemical parameters. During the traditional process, endogenous cyanogens were almost totally degraded, plant cell walls were lysed by the simultaneous action of pectin methylesterase and pectate lysate, and organic acids (C2 to C4) were produced. Most microorganisms identified were found to be facultat...

  6. The effect of microbial starter composition on cassava chips fermentation for the production of fermented cassava flour

    Science.gov (United States)

    Kresnowati, M. T. A. P.; Listianingrum, Zaenudin, Ahmad; Trihatmoko, Kharisrama

    2015-12-01

    The processing of cassava into fermented cassava flour (fercaf) or the widely known as modified cassava flour (mocaf) presents an alternative solution to improve the competitiveness of local foods and to support national food security. However, the mass production of fercaf is being limited by several problems, among which is the availability of starter cultures. This paper presents the mapping of the effect of microbial starter compositions on the nutritional content of fercaf in order to obtain the suitable nutritional composition. Based on their enzymatic activities, the combination of Lactobacillus plantarum, Bacillus subtilis, and Aspergillus oryzae were tested during the study. In addition, commercial starter was also tested. During the fermentation, the dynamics in microbial population were measured as well as changes in cyanogenic glucoside content. The microbial starter composition was observed to affect the dynamics in microbial populationcynaogenic glucoside content of the produced fercaf. In general, steady state microbial population was reached within 12 hours of fermentation. Cyanogenic glucoside was observed to decrease along the fermentation.

  7. Chemical composition, functional and pasting properties of cassava starch and soy protein concentrate blends.

    Science.gov (United States)

    Chinma, Chiemela Enyinnaya; Ariahu, Charles Chukwuma; Abu, Joseph Oneh

    2013-12-01

    The chemical, functional and pasting properties of cassava starch and soy protein concentrate blends intended for biofilm processing were studied. Cassava starch and soy protein concentrates were prepared and mixed at different proportions (100: 0%; 90 : 10%; 80 : 20%; 70 : 30%; 60;40% and 50: 50%). Addition of varying levels of soy protein concentrates to cassava starch led to increases in moisture (from 7.10 to 9.17%), protein ( from 0.32 to 79.03%), ash (from 0.45 to 2.67%) and fat (from 0.17 to 0.98%) contents while crude fiber, carbohydrate and amylose contents decreased from ( 1.19 to 0.38%, 90.77 to 57.01% and 29.45 to 23.04%) respectively . Water absorption capacity and swelling power of cassava starch were improved as a result of soy protein concentrate addition while syneresis and solubility value of composite blends were lower than 100% cassava starch. In general, cassava-soy protein concentrate blends formed firmer gels than cassava starch alone. There were significant (p ≤ 0.05) increases in peak viscosity (from 160.12 to 268.32RVU), final viscosity (from 140.41 to 211.08RVU) and pasting temperature (from 71.00 to 72.32 °C ) of cassava starch due to addition of soy protein concentrate. These results suggest that the addition of soy protein concentrate to cassava starch affected the studied functional properties of cassava starch as evidenced by changes such as reduced syneresis, and solubility that are desirable when considering this biopolymer as an edible biofilm.

  8. Aflatoxin-producing Aspergillus spp. and aflatoxin levels in stored cassava chips as affected by processing practices

    DEFF Research Database (Denmark)

    Essono, G.; Ayodele, M.; Akoa, A.;

    2009-01-01

    Cassava chips (cassava balls, and cassava pellets) are derived cassava products traditionally produced by farmers in sub-Saharan Africa following fermentation, and drying of fresh roots of cassava, and are widely consumed in Cameroon. Once produced, this food commodity can be stored for more than...... two months and contaminated by a wide array of harmful microbes. In order to assess persistence of toxigenic fungi in cassava chips, aflatoxin-producing fungi (Aspergillus flavus, Aspergillus nomius, and Aspergillus parasiticus) and aflatoxins were contrasted at regular intervals in home......-stored cassava chips collected in two locations of southern Cameroon throughout a two-month monitoring period. Three hundred and forty-six isolates of aflatoxin-producing fungi were found to be associated with all samples. A. flavus contaminated more samples in both types of chips (267 isolates in 53 samples...

  9. Marker-assisted selection in common beans and cassava

    International Nuclear Information System (INIS)

    Marker-assisted selection (MAS) in common beans (Phaseolus vulgaris L.) and cassava (Manihot esculenta) is reviewed in relation to the breeding system of each crop and the breeding goals of International Agricultural Research Centres (IARCs) and National Agricultural Research Systems (NARS). The importance of each crop is highlighted and examples of successful use of molecular markers within selection cycles and breeding programmes are given for each. For common beans, examples are given of gene tagging for several traits that are important for bean breeding for tropical environments and aspects considered that contribute to successful application of MAS. Simple traits that are tagged with easy-to-use markers are discussed first as they were the first traits prioritized for breeding at the International Center for Tropical Agriculture (CIAT) and with NARS partners in Central America, Colombia and eastern Africa. The specific genes for MAS selection were the bgm-1 gene for bean golden yellow mosaic virus (BGYMV) resistance and the bc-3 gene for bean common mosaic virus (BCMV) resistance. MAS was efficient for reducing breeding costs under both circumstances as land and labour savings resulted from eliminating susceptible individuals. The use of markers for other simply inherited traits in marker-assisted backcrossing and introgression across Andean and Mesoamerican gene pools is suggested. The possibility of using MAS for quantitative traits such as low soil phosphorus adaptation is also discussed as are the advantages and disadvantages of MAS in a breeding programme. For cassava, the use of multiple flanking markers for selection of a dominant gene, CMD2 for cassava mosaic virus (CMV) resistance at CIAT and the International Institute of Tropical Agriculture (IITA) as well as with NARS partners in the United Republic of Tanzania using a participatory plant breeding scheme are reviewed. MAS for the same gene is important during introgression of cassava green mite

  10. Cassava stillage and its anaerobic fermentation liquid as external carbon sources in biological nutrient removal*

    Science.gov (United States)

    Bu, Fan; Hu, Xiang; Xie, Li; Zhou, Qi

    2015-01-01

    The aim of this study was to investigate the effects of one kind of food industry effluent, cassava stillage and its anaerobic fermentation liquid, on biological nutrient removal (BNR) from municipal wastewater in anaerobic-anoxic-aerobic sequencing batch reactors (SBRs). Experiments were carried out with cassava stillage supernatant and its anaerobic fermentation liquid, and one pure compound (sodium acetate) served as an external carbon source. Cyclic studies indicated that the cassava by-products not only affected the transformation of nitrogen, phosphorus, poly-β-hydroxyalkanoates (PHAs), and glycogen in the BNR process, but also resulted in higher removal efficiencies for phosphorus and nitrogen compared with sodium acetate. Furthermore, assays for phosphorus accumulating organisms (PAOs) and denitrifying phosphorus accumulating organisms (DPAOs) demonstrated that the proportion of DPAOs to PAOs reached 62.6% (Day 86) and 61.8% (Day 65) when using cassava stillage and its anaerobic fermentation liquid, respectively, as the external carbon source. In addition, the nitrate utilization rates (NURs) of the cassava by-products were in the range of 5.49–5.99 g N/(kg MLVSS∙h) (MLVSS is mixed liquor volatile suspended solids) and 6.63–6.81 g N/(kg MLVSS∙h), respectively. The improvement in BNR performance and the reduction in the amount of cassava stillage to be treated in-situ make cassava stillage and its anaerobic fermentation liquid attractive alternatives to sodium acetate as external carbon sources for BNR processes. PMID:25845364

  11. Evaluation of synergistic effect in vacuum pack, refrigeration and irradiated treatments of minimally processed cassava

    International Nuclear Information System (INIS)

    Cassava is cultivated almost all over the world and it is considered one of the most important nutritious sources of calories in the human diet. Cassava is a viable food against starvation in several poor areas of the world because it is an extremely resistant culture and may reach satisfactory economical yield. We utilized vacuum packed industrialized cassava irradiated with 0,1 kGy, 3kGy and 5kGy and stored under refrigeration for 1, 21, 30 and 50 days. Our objective was to analyse the synergistic effect of vacuum packing, irradiation and refrigeration on the preservation of minimally processed cassava. The samples were analyzed for pH, acidity, weight, humidity, texture and color. The irradiation did not affect the chemical characteristics of the cassava. Neither the pH nor the acidity, the most relevant variables to verify deterioration in cassava, presented significant alterations during the period of storage. Comparing the irradiated treatments, the dose of 1kGy and 3kGy affected the physic-chemical characteristics of the cassava the least during the period of storage and refrigeration for 50 days; the doses of 1kGy,3kGy and 5kGy scored the highest rates the sensorial analysis during the period of storage for 21 days. (author)

  12. Milk production and economic assessment of cassava bagasse in the feed of dairy cows

    Directory of Open Access Journals (Sweden)

    Leandro Pereira Lima

    2015-08-01

    Full Text Available The addition of 0; 5; 10 and 15% cassava bagasse, based on the dry matter of the total diet of crossbred Holstein v. Zebu cows, was evaluated on milk production and composition and on the impacts of diet costs. The animals, weighing an average of 478.5 kg, were in the middle third lactation period. Diet with 15% cassava bagasse provided a 13.2% increase in production when compared to control. Feed conversion had a quadratic effect with minimum point at 4.2% of cassava bagasse inclusion. Crude protein, the only milk component that changed, increased linearly with the inclusion of cassava bagasse levels. Treatment with 15% cassava bagasse caused a more effective operational cost (42.8% higher when compared to control and the highest leveling point for milk production and price. The lowest leveling points were treatments with 5 and 10% inclusion of cassava bagasse, which had the best economic results. Concentrates caused cost increase, particularly when roughage : concentrate ratio decreased due to higher cassava bagasse inclusion levels.

  13. Cassava: The Drought, War and Famine Crop in a Changing World

    Directory of Open Access Journals (Sweden)

    Anna Burns

    2010-11-01

    Full Text Available Cassava is the sixth most important crop, in terms of global annual production. Cassava is grown primarily for its starchy tuberous roots, which are an important staple for more than 800 million people, mostly in sub-Saharan Africa, but also in other parts of Africa, Asia, the Pacific and South America. Cassava is important for both small-scale farmers and larger-scale plantations due to its low requirement for nutrients, ability to tolerate dry conditions and easy low-cost propagation. It is sometimes referred to as the “drought, war and famine crop of the developing world” and reliance upon this crop is expected to increase in the coming years as the global climate changes. As with all crops, cassava presents some challenges which need to be addressed, especially if its production is to continue to expand. We highlight here a number of key issues around the continued and increased reliance upon cassava as a staple food crop. Cassava contains cyanogenic glycosides that release hydrogen cyanide and many cultivars are toxic if not processed before consumption. The degree of toxicity is altered by plant breeding, agricultural practice, environmental conditions and methods of food preparation. We conclude that use of cassava has the potential to help many countries achieve food security in a sustainable manner, in the face of significant environmental change, but that its introduction should be accompanied by appropriate education about its toxicity.

  14. Molecular evolution and functional divergence of soluble starch synthase genes in cassava (manihot esculenta crantz).

    Science.gov (United States)

    Yang, Zefeng; Wang, Yifan; Xu, Shuhui; Xu, Chenwu; Yan, Changjie

    2013-01-01

    Soluble starch synthases (SSs) are major enzymes involved in starch biosynthesis in plants. Cassava starch has many remarkable characteristics, which should be influenced by the evolution of SS genes in this starchy root crop. In this work, we performed a comprehensive phylogenetic and evolutionary analysis of the soluble starch synthases in cassava. Genome-wide identification showed that there are 9 genes encoding soluble starch synthases in cassava. All of the soluble starch synthases encoded by these genes contain both Glyco_transf_5 and Glycos_transf_1 domains, and a correlation analysis showed evidence of coevolution between these 2 domains in cassava SS genes. The SS genes in land plants can be divided into 6 subfamilies that were formed before the origin of seed plants, and species-specific expansion has contributed to the evolution of this family in cassava. A functional divergence analysis for this family provided statistical evidence for shifted evolutionary rates between the subfamilies of land plant soluble starch synthases. Although the main selective pressure acting on land plant SS genes was purifying selection, our results also revealed that point mutation with positive selection contributed to the evolution of 2 SS genes in cassava. The remarkable cassava starch characteristics might be the result of both the duplication and adaptive selection of SS genes.

  15. Sequencing wild and cultivated cassava and related species reveals extensive interspecific hybridization and genetic diversity.

    Science.gov (United States)

    Bredeson, Jessen V; Lyons, Jessica B; Prochnik, Simon E; Wu, G Albert; Ha, Cindy M; Edsinger-Gonzales, Eric; Grimwood, Jane; Schmutz, Jeremy; Rabbi, Ismail Y; Egesi, Chiedozie; Nauluvula, Poasa; Lebot, Vincent; Ndunguru, Joseph; Mkamilo, Geoffrey; Bart, Rebecca S; Setter, Tim L; Gleadow, Roslyn M; Kulakow, Peter; Ferguson, Morag E; Rounsley, Steve; Rokhsar, Daniel S

    2016-05-01

    Cassava (Manihot esculenta) provides calories and nutrition for more than half a billion people. It was domesticated by native Amazonian peoples through cultivation of the wild progenitor M. esculenta ssp. flabellifolia and is now grown in tropical regions worldwide. Here we provide a high-quality genome assembly for cassava with improved contiguity, linkage, and completeness; almost 97% of genes are anchored to chromosomes. We find that paleotetraploidy in cassava is shared with the related rubber tree Hevea, providing a resource for comparative studies. We also sequence a global collection of 58 Manihot accessions, including cultivated and wild cassava accessions and related species such as Ceará or India rubber (M. glaziovii), and genotype 268 African cassava varieties. We find widespread interspecific admixture, and detect the genetic signature of past cassava breeding programs. As a clonally propagated crop, cassava is especially vulnerable to pathogens and abiotic stresses. This genomic resource will inform future genome-enabled breeding efforts to improve this staple crop. PMID:27088722

  16. Improvement of the nutrient qualities of cassava fermented end-products

    International Nuclear Information System (INIS)

    The yeast strains Saccharomycopsis fibuliger NRRL (Y-2388), Saccharomyces diastaticus NRRL (Y-2416 and Y-4238), Schwaniomyces occidentalis NRRLY-2477 as well as nor-leucine resistant and amylase-overproducing mutants of NRRL-Y-2338 (obtained with the help of NTG-mutagenesis) were used to study their abilities to increase the yield of protein into the cassava fermenting pulp. Their growth kinetics, amylase activity and biomass production initially studied on 2% MYPS medium. S. fibuliger (Y-2388) gave the highest biomass concentration (13,4 g/e) and was found to be superior to other wild strains for protein enrichment of cassava through fermentation. The optimization of the condition for fermentation revealed that 5% w/v of the cassava pulp at pH 6 with an addition of the yeast extract increased the protein content of cassava from 2.8% to 5.6%. The use of amylase overproducing mutants of S. fibuliger Y-2388 inoculated singly or in combination with others did not promote the enrichment of cassava, whereas nor-leucine resistant mutants considerable increased the protein content in the cassava pulp and no supplementation of the pulp with any nutrients is required. Hence, both S. fibuligera Y-2388 wild and its nor-leucine resistant mutant should be considered as a potential inocula with respect to protein enrichment of the cassava fermented end-product. (author). 3 figs, 9 tabs

  17. [Degradation of cassava residue by the cellulose degradation composite microbial system MC1].

    Science.gov (United States)

    Guo, Peng; Wang, Xiao-Fen; Zhu, Wan-Bin; Cheng, Xu; Cui, Zong-Jun

    2008-03-01

    The lignocelluloses of cassava residue are good biomass resources. They are mainly used to produce feeds and alcohol. It is a promising approach to utilize them to produce methane. But it is difficult to use cassava residue for producing methane because of its dispersive solid matter and much water. A cellulose degradation composite microbial system MC1 was applied to degrade cassava residue discarded from cassava starch manufactory, and the composition of the lignocelluloses and the soluble ingredients of cassava residue were analyzed. After 18 days' cultivation, the total weight of the cassava residue was reduced by 47.3%, the cellulose, hemi-cellulose and lignin of the cassava residue were reduced by 22.7%, 90.4% and 11.3%, respectively, and 85% of the whole weight relief was made by MC1 within 6 days. The soluble ingredients of the cassava residue were increased from the incipient 18% to 33% in the third day which was the peak value in the process. The total amount of the volatile products, analyzed by GC-MS, came to a maximum in the sixth day. Twelve kinds of volatile products in the fermentation broth were determined, in which ethanol, acetic acid, 1, 2-ethanediol, butanoic acid and glycerine were the major compounds, and they can be utilized by methanogenic organism directly or be changed into compounds that can be utilized by methanogens organism directly. Accordingly, it is very hopeful to use MC1 to degrade cassava residue as a method of prefermentation in methane fermentation.

  18. Genotype × environment interaction effects on early fresh storage root yield and related traits in cassava

    Directory of Open Access Journals (Sweden)

    Robooni Tumuhimbise

    2014-10-01

    Full Text Available Cassava (Manihot esculenta Crantz is an important root crop worldwide. It exhibits substantial differential genotypic responses to varying environmental conditions, a phenomenon termed genotype × environment interaction (GEI. A significant GEI presents challenges in the selection of superior genotypes. The objective of this study was to examine the effect of genotype, environment and GEI on early fresh storage root yield (FSRY and related traits in cassava. Accordingly, 12 cassava genotypes were evaluated in a randomised complete block design at three contrasting locations (Jinja, Nakasongola and Namulonge in Uganda. Trials were harvested nine months after planting and the data collected were analysed using the additive main effects and multiplicative interaction (AMMI model. The AMMI analysis of variance showed significant variation among genotypes for early FSRY and all other traits assessed. Locations were significantly different for all traits except for cassava brown streak disease root necrosis. The GEI effect was non-significant for early FSRY, but significant for other traits. For early FSRY, 48.5% of the treatment sum of squares was attributable to genotypes, 27.3% to environments, and 24.1% to GEI, indicating a predominance of genotypic variation for this trait. Predominance of genotypic variation was also observed for all the other traits. A majority of the genotypes (67% had low interaction effects with locations for early FSRY, with Akena, CT2, CT4 and NASE14 being the most stable genotypes for the trait. Significant negative correlation was observed between cassava mosaic disease severity and early FSRY and storage root number, indicating significant negative effects of cassava mosaic disease on early FSRY and stability in cassava. The information generated will inform future selection initiatives for superior early-yielding cassava genotypes combining resistance to cassava mosaic and brown streak diseases in Uganda.

  19. Density Equation of Cassava-Stalk Briquettes Under Moderate Die-Pressure

    Directory of Open Access Journals (Sweden)

    Patomsok Wilaipon

    2010-01-01

    Full Text Available Problem statement: Agricultural residues seem to be the most promising energy resources for developing countries. However, the majority of them have low energy density. One of the favorable technologies for enhancing that property is briquetting. For the case of Phitsanulok, a province in Northern Thailand, cassava is one of the most important crops. Therefore, a large amount of cassava stalk is left in the field after harvest. This study was aimed to investigate the quantity of cassava stalk in this province and to study cassava stalk briquette production. Approach: The potential energy from cassava stalk was calculated based on the productivity, residue-to-product ratio, residue returned to soil ratio and its heating value. Besides, the effects of moderate-range compression pressure, 70-110 bar, and the binder ratio, 10-20%, on briquette density were investigated. An empirical model was also developed and validated. Results: Base on the estimation, the quantity of usable cassava stalk in this area was approximately 18 kton year-1. The heating value of cassava stalk was found to be 16.39 MJ kg-1. Therefore, the total energy over 289 TJ year-1 can be obtained from this agricultural waste. According to the experiment, briquette density was in the range of 0.40-0.77 g cm-3. The coefficient of multiple determination for prediction of the proposed model was about 94.7%. Conclusion: It appeared that cassava stalk has high potential as energy source for this area. The density of cassava stalk briquette was increased with an increase in compaction pressure. Besides, it was found that the proposed model can be used for density prediction over the studied range.

  20. Genotype × environment interaction effects on early fresh storage root yield and related traits in cassava

    Institute of Scientific and Technical Information of China (English)

    Robooni; Tumuhimbise; Rob; Melis; Paul; Shanahan; Robert; Kawuki

    2014-01-01

    Cassava(Manihot esculenta Crantz) is an important root crop worldwide. It exhibits substantial differential genotypic responses to varying environmental conditions, a phenomenon termed genotype × environment interaction(GEI). A significant GEI presents challenges in the selection of superior genotypes. The objective of this study was to examine the effect of genotype,environment and GEI on early fresh storage root yield(FSRY) and related traits in cassava.Accordingly, 12 cassava genotypes were evaluated in a randomised complete block design at three contrasting locations(Jinja, Nakasongola and Namulonge) in Uganda. Trials were harvested nine months after planting and the data collected were analysed using the additive main effects and multiplicative interaction(AMMI) model. The AMMI analysis of variance showed significant variation among genotypes for early FSRY and all other traits assessed.Locations were significantly different for all traits except for cassava brown streak disease root necrosis. The GEI effect was non-significant for early FSRY, but significant for other traits. For early FSRY, 48.5% of the treatment sum of squares was attributable to genotypes, 27.3% to environments, and 24.1% to GEI, indicating a predominance of genotypic variation for this trait.Predominance of genotypic variation was also observed for all the other traits. A majority of the genotypes(67%) had low interaction effects with locations for early FSRY, with Akena, CT2, CT4 and NASE14 being the most stable genotypes for the trait. Significant negative correlation was observed between cassava mosaic disease severity and early FSRY and storage root number,indicating significant negative effects of cassava mosaic disease on early FSRY and stability in cassava. The information generated will inform future selection initiatives for superior early-yielding cassava genotypes combining resistance to cassava mosaic and brown streak diseases in Uganda.

  1. Effect of feeding cassava (Manihot esculenta Crantz) root meal on growth performance, hydrocyanide intake and haematological parameters of broiler chicks.

    Science.gov (United States)

    Akapo, Abiola Olajetemi; Oso, Abimbola Oladele; Bamgbose, Adeyemi Mustapha; Sanwo, Kehinde A; Jegede, Adebayo Vincent; Sobayo, Richard Abayomi; Idowu, Olusegun Mark; Fan, Juexin; Li, Lili; Olorunsola, Rotimi A

    2014-10-01

    The effect of feeding cassava root meal on growth performance, hydrocyanide intake, haematological indices and serum thiocyanate concentration of broiler chicks was investigated using 300-day-old male broilers. There were five dietary treatments arranged in a 2 × 2 + 1 factorial arrangement of two processing methods of cassava root (peeled and unpeeled) included at two levels (100 and 200 g/kg) plus a control diet (maize-based diet, containing no cassava root). Each treatment was replicated six times with ten birds per replicate. The feeding trial lasted for 28 days. Control-fed birds had the highest overall (P cassava root meal (PCRM) had the least (P cassava root meal had higher (P cassava root meal. Dietary inclusion of peeled cassava root meal (PCRM) for broiler chicks resulted in increased final liveweight (P cassava root meal (UCRM). The least (P cassava root resulted in significant increase (P cassava root poses a threat on growth and health status of broiler chicks.

  2. Production and Purification of Bioethanol from Molasses and Cassava

    Science.gov (United States)

    Maryana, Roni; Wahono, Satriyo Krido

    2009-09-01

    This research aim to analysis bioethanol purification process. Bioethanol from cassava has been produced in previous research and the ethanol from molasses was taken from Bekonang region. The production of bioethanol from cassava was carried out through several processes such as homogenization, adding of α-amylase, β-amylase and yeast (Saccharomyces c). Two types of laboratory scale distillator have been used, the first type is 50 cm length and 4 cm diameter. The second type distillator is 30 cm length and 9 cm diameter. Both types have been used to distill bioethanol The initial concentration after the fermentation process is 15% for bioethanol from cassava and 20-30% ethanol from molasses. The results of first type distillator are 90% of bioethanol at 50° C and yield 2.5%; 70% of bioethanol at 60° C and yield 11.2%. 32% of bioethanol at 70° C and yield 42%. Meanwhile the second distillator results are 84% of bioethanol at 50° C with yield 12%; 51% of bioethanol at 60° C with yield 35.5%; 20% of bioethanol at 70° C with yield 78.8%; 16% of bioethanol at 80° C with yield 81.6%. The ethanol from molasses has been distillated once times in Bekonang after the fermentation process, the yield was about 20%. In this research first type distillator and the initial concentration is 20% has been used. The results are 95% of bioethanol at 75° C with yield 8%; 94% of bioethanol at 85° C with yield 13% when vacuum pump was used. And 94% of bioethanol at 90° C with yield 3.7% and 94% of bioethanol at 96° C with yield 10.27% without vacuum pump. The bioethanol purification use second type distillator more effective than first type distillator.

  3. Analysis of in vitro regenerated cassava plants using RAPD technology

    International Nuclear Information System (INIS)

    Cassava is an important tuber crop grown in tropical and subtropical regions. Protocols for regeneration from tissue culture are very genotype dependent and in many cultivars quite ineffective, therefore improvement programmes through genetic engineering are restricted. Recently, protocols were developed for efficient somatic embryogenesis and/or organogenesis using zygotic embryos and nodal axillary meristems to minimize genotype dependency. Buds were regenerated directly from the exercised explants after a two step culture procedure. In the embryo explants, profilic shoot formation occurred within 2-3 weeks on a medium containing 0.5 mg I-1 BAP alone, or in combination with 0.1 mg I-1 NAA. Nodal explants with an axillary meristem were used to initiate a round, compact, 'bulb like' structure in the high cytokinin containing medium. In the presence of NAA (0.1 mg I-1), BAP (1 mg I-1) and GA3 (0.1 mg I-1), these structures produced multiple shoots. Efficient somatic embryogenesis was obtained from the cotyledon explants. Plants were obtained from all the African genotypes tested, although at different frequencies. The rooting of regenerated shoots exceeded 95% in phytohormone free medium. The polidy of the regenerants was examined using flow cytometry; no change in their ploidy level was observed. The random amplified polymorphic DAN (RAPD)-polymerase chain reaction (PCR) technique was employed to investigate molecular differences and also to generate polymorphic DNA markers in the in vitro regenerated Cassava plants. Twenty primers were used to generate patterns from several regenerants of two Cassava cultivars. The validity of using RAPD markers in such studies is discussed. (author). 3 refs, 1 tab

  4. Biogas Production Using Anaerobic Biodigester from Cassava Starch Effluent

    Directory of Open Access Journals (Sweden)

    S. Sunarso

    2010-12-01

    Full Text Available IKMs’ factory activity in Margoyoso produces liquid and solid wastes. The possible alternative was to use the liquid effluent as biogas raw material. This study focuses on the used of urea, ruminant, yeast, microalgae, the treatment of gelled and ungelled feed for biogas production, pH control during biogas production using buffer Na2CO3, and feeding management in the semi-continuous process of biogas production that perform at ambient temperature for 30 days. Ruminant bacteria, yeast, urea, and microalgae was added 10% (v/v, 0.08% (w/v, 0.04% (w/v, 50% (v/v of mixing solution volume, respectively. The pH of slurry was adjusted with range 6.8-7.2 and was measured daily and corrected when necessary with Na2CO3. The total biogas production was measured daily by the water displacement technique. Biogas production from the ungelling and gelling mixture of cassava starch effluent, yeast, ruminant bacteria, and urea were 726.43 ml/g total solid and 198 ml/g total solid. Biogas production from ungelling mixture without yeast was 58.6 ml/g total solid. Biogas production from ungelling mixture added by microalgae without yeast was 58.72 ml/g total solid and that with yeast was 189 ml/g total solid. Biogas production from ungelling mixture of cassava starch effluent, yeast, ruminant bacteria, and urea in semi-continuous process was 581.15 ml/g total solid. Adding of microalgae as nitrogen source did not give significant effect to biogas production. But adding of yeast as substrate activator was very helpful to accelerate biogas production. The biogas production increased after cassava starch effluent and yeast was added. Requirement of sodium carbonate (Na2CO3 to increase alkalinity or buffering capacity of fermenting solution depends on pH-value

  5. Water Quality Changes Associated with Cassava Production: Case Study of White Volta Bain.

    Science.gov (United States)

    Awotwi, Alfred; Bediako, Michael Asare; Harris, Emmanuel; Forkuo, Eric Kwabena

    2016-08-01

    The outcome reveal that as the land use in the catchment areas change from mixed agricultural to cassava cultivation, the simulated loads and concentrations of nitrogen species from cassava land-use scenario recorded reduction. The resultant concentrations of nitrate and nitrite for both current and future land-use scenarios are all below the daily limit suggested by the WHO, (World Health Organization). For the phosphate concentration, an increase of 4.21% was depicted under cassava land-use scenario. The results show that SWAT is a reliable water quality model, capable of simulating accurate information for developing environmental management plans. PMID:27626092

  6. Cassava in South America, Brazil's contribution and the lesson to be learned from India.

    Science.gov (United States)

    Nassar, Nagib M A

    2006-11-30

    South America is responsible for about half of the cassava world production. In the 1970's productivity of the crop on the continent was about 15 ton/ha, and dropped continuously until reaching 12 ton/ha in 2004. India's productivity of cassava increased from 10 ton/ha in the 1970's to 28 ton/ha in 2004. Brazil contributed significantly to improving cassava crops through the Instituto Agronômico de Campinas in the 1960's and 1970's. The Universidade de Brasília released high-protein content hybrids, apomictic clones and explored the potential of indigenous landraces.

  7. Water Quality Changes Associated with Cassava Production: Case Study of White Volta Bain.

    Science.gov (United States)

    Awotwi, Alfred; Bediako, Michael Asare; Harris, Emmanuel; Forkuo, Eric Kwabena

    2016-08-01

    The outcome reveal that as the land use in the catchment areas change from mixed agricultural to cassava cultivation, the simulated loads and concentrations of nitrogen species from cassava land-use scenario recorded reduction. The resultant concentrations of nitrate and nitrite for both current and future land-use scenarios are all below the daily limit suggested by the WHO, (World Health Organization). For the phosphate concentration, an increase of 4.21% was depicted under cassava land-use scenario. The results show that SWAT is a reliable water quality model, capable of simulating accurate information for developing environmental management plans.

  8. Effect of processing conditions on the texture of reconstituted cassava dough

    Directory of Open Access Journals (Sweden)

    E. Rodríguez-Sandoval

    2008-12-01

    Full Text Available Deformability modulus, hardness, cohesiveness and adhesiveness of cassava dough reconstituted from precooked flour were evaluated using a lubricated compression test and texture profile analysis. Cassava parenchyma processed under different cooking conditions and left at either -5ºC or -20ºC for 24 h was used to make flour, which was reconstituted into dough. As temperature decreased to -20ºC during the storage period of cooked parenchyma, deformability modulus, hardness and cohesiveness of dough increased significantly. The temperature during the storage period was the most important factor affecting the textural properties of cassava dough.

  9. Enhanced thermophilic fermentative hydrogen production from cassava stillage by chemical pretreatments

    DEFF Research Database (Denmark)

    Wang, Wen; Luo, Gang; Xie, Li;

    2013-01-01

    Acid and alkaline pretreatments for enhanced hydrogen production from cassava stillage were investigated in the present study. The result showed that acid pretreatment was suitable for enhancement of soluble carbohydrate while alkaline pretreatment stimulated more soluble total organic carbon...... production from cassava stillage. Acid pretreatment thereby has higher capacity to promote hydrogen production compared with alkaline pretreatment. Effects of pretreatment temperature, time and acid concentration on hydrogen production were also revealed by response surface methodology. The results showed...... production of 434 mL, 67% higher than raw cassava stillage....

  10. Production of methane by co-digestion of cassava pulp with various concentrations of pig manure

    DEFF Research Database (Denmark)

    Panichnumsin, Pan; Nopharatana, Annop; Ahring, Birgitte Kiær;

    2010-01-01

    Cassava pulp is a major by-product produced in a cassava starch factory, containing 50-60% of starch (dry basis). Therefore, in this study we are considering its potential as a raw material substrate for the production of methane. To ensure sufficient amounts of nutrients for the anaerobic...... digestion process, the potential of co-digestion of cassava pulp (CP) with pig manure (PM) was further examined. The effect of the co-substrate mixture ratio was carried out in a semi-continuously fed stirred tank reactor (CSTR) operated under mesophilic condition (37 C) and at a constant OLR of 3.5 kg VS m...

  11. Cassava root meal as substitute for maize in layers ration

    OpenAIRE

    M Anaeto; LC Adighibe

    2011-01-01

    The effect of replacing maize with graded levels of cassava root meal (CRM) as energy source in the diet of laying hens was evaluated during the eight weeks of feeding experiment on performance and cost benefits on layers. Forty-five Nera black laying hens of 24 weeks of age were allocated to five dietary treatments, with nine birds per treatment in a completely randomized design. CRM was used to formulate the diets at 0, 25, 50, 75, and 100%. The result showed that the feed intake of birds i...

  12. Cassava flour and starch : progress in research and development

    OpenAIRE

    Giraud, Eric; Brauman, Alain; Kéléke, S.; Gosselin, Laurent; Raimbault, Maurice

    1996-01-01

    An amylolytic lactic acid bacterium, identified as #Lactobacillus plantarum$, was isolated from cassava roots (#Manihot esculenta$ var. Ngansa) during retting. Cultured on starch, the strain displayed a growth rate of 0.43 per hour, a biomass yield of 0.19 g/g, and a lactate yield of 0.81 g/g. The growth kinetics were similar on starch and glucose. Enough enzyme was synthesized, and starch hydrolysis was not a limiting factor for growth. The synthesized amylolytic enzyme was purified by fract...

  13. Alterations of reproduction system in a polyploidized cassava interspecific hybrid.

    Science.gov (United States)

    Nassar, Nagib M A; Graciano-Ribeiro, Dalva; Gomes, Paula F; Hashimoto, Danielle Y C

    2010-04-01

    The objective of this research was to examine how much polyploidy may affect seed and root formation in cassava interspecific hybrids Manihot esculenta Crantz xM. oligantha Pax. A polyploid type was induced by colchicine treatment to lateral buds followed by propagating vegetatively arising stems. Cytogenetic and anatomical analyses were made on both polyploid and diploid types. The polyploid type showed extensive chromosome pairing and pollen viability. Multiembryonic ovule frequency increased in polyploid plants. Stalks became woody and propagation through roots difficult, the edible roots increased, however, in size. PMID:20536543

  14. Energy and greenhouse gas balances of cassava-based ethanol

    International Nuclear Information System (INIS)

    Biofuel production has been promoted to save fossil fuels and reduce greenhouse gas (GHG) emissions. However, there have been concerns about the potential of biofuel to improve energy efficiency and mitigate climate change. This paper investigates energy efficiency and GHG emission saving of cassava-based ethanol as energy for transportation. Energy and GHG balances are calculated for a functional unit of 1 km of road transportation using life-cycle assessment and considering effects of land use change (LUC). Based on a case study in Vietnam, the results show that the energy input for and GHG emissions from ethanol production are 0.93 MJ and 34.95 g carbon dioxide equivalent per megajoule of ethanol respectively. The use of E5 and E10 as a substitute for gasoline results in energy savings, provided that their fuel consumption in terms of liter per kilometer of transportation is not exceeding the consumption of gasoline per kilometer by more than 2.4% and 4.5% respectively. It will reduce GHG emissions, provided that the fuel consumption of E5 and E10 is not exceeding the consumption of gasoline per kilometer by more than 3.8% and 7.8% respectively. The quantitative effects depend on the efficiency in production and on the fuel efficiency of E5 and E10. The variations in results of energy input and GHG emissions in the ethanol production among studies are due to differences in coverage of effects of LUC, CO2 photosynthesis of cassava, yields of cassava, energy efficiency in farming, and by-product analyses. -- Highlights: ► Cassava-based ethanol substitution for gasoline in form of E5 could save 1.4 MJ km−1 ► Ethanol substitution for gasoline in form of E5 reduces a CO2e emission of 156 g km−1 ► We examined changes in fuel efficiency of blends affecting energy and GHG balances. ► LUC and change in soil management lead to a CO2e emission of 942 g L−1 of ethanol. ► LUC effects, energy inputs, yields, and by-products explain results among studies

  15. Resistance to Sri Lankan Cassava Mosaic Virus (SLCMV) in Genetically Engineered Cassava cv. KU50 through RNA Silencing

    KAUST Repository

    Ntui, Valentine Otang

    2015-04-22

    Cassava ranks fifth among the starch producing crops of the world, its annual bioethanol yield is higher than for any other crop. Cassava cultivar KU50, the most widely grown cultivar for non-food purposes is susceptible to Sri Lankan cassava mosaic virus (SLCMV). The objective of this work was to engineer resistance to SLCMV by RNA interference (RNAi) in order to increase biomass yield, an important aspect for bioethanol production. Here, we produced transgenic KU50 lines expressing dsRNA homologous to the region between the AV2 and AV1 of DNA A of SLCMV. High level expression of dsRNA of SLCMV did not induce any growth abnormality in the transgenic plants. Transgenic lines displayed high levels of resistance to SLCMV compared to the wild-type plants and no virus load could be detected in uninoculated new leaves of the infected resistant lines after PCR amplification and RT-PCR analysis. The agronomic performance of the transgenic lines was unimpaired after inoculation with the virus as the plants presented similar growth when compared to the mock inoculated control plants and revealed no apparent reduction in the amount and weight of tubers produced. We show that the resistance is correlated with post-transcriptional gene silencing because of the production of transgene specific siRNA. The results demonstrate that transgenic lines exhibited high levels of resistance to SLCMV. This resistance coupled with the desirable yield components in the transgenic lines makes them better candidates for exploitation in the production of biomass as well as bioethanol.

  16. Resistance to Sri Lankan cassava mosaic virus (SLCMV in genetically engineered cassava cv. KU50 through RNA silencing.

    Directory of Open Access Journals (Sweden)

    Valentine Otang Ntui

    Full Text Available Cassava ranks fifth among the starch producing crops of the world, its annual bioethanol yield is higher than for any other crop. Cassava cultivar KU50, the most widely grown cultivar for non-food purposes is susceptible to Sri Lankan cassava mosaic virus (SLCMV. The objective of this work was to engineer resistance to SLCMV by RNA interference (RNAi in order to increase biomass yield, an important aspect for bioethanol production. Here, we produced transgenic KU50 lines expressing dsRNA homologous to the region between the AV2 and AV1 of DNA A of SLCMV. High level expression of dsRNA of SLCMV did not induce any growth abnormality in the transgenic plants. Transgenic lines displayed high levels of resistance to SLCMV compared to the wild-type plants and no virus load could be detected in uninoculated new leaves of the infected resistant lines after PCR amplification and RT-PCR analysis. The agronomic performance of the transgenic lines was unimpaired after inoculation with the virus as the plants presented similar growth when compared to the mock inoculated control plants and revealed no apparent reduction in the amount and weight of tubers produced. We show that the resistance is correlated with post-transcriptional gene silencing because of the production of transgene specific siRNA. The results demonstrate that transgenic lines exhibited high levels of resistance to SLCMV. This resistance coupled with the desirable yield components in the transgenic lines makes them better candidates for exploitation in the production of biomass as well as bioethanol.

  17. Resistance to Sri Lankan cassava mosaic virus (SLCMV) in genetically engineered cassava cv. KU50 through RNA silencing.

    Science.gov (United States)

    Ntui, Valentine Otang; Kong, Kynet; Khan, Raham Sher; Igawa, Tomoko; Janavi, Gnanaguru Janaky; Rabindran, Ramalingam; Nakamura, Ikuo; Mii, Masahiro

    2015-01-01

    Cassava ranks fifth among the starch producing crops of the world, its annual bioethanol yield is higher than for any other crop. Cassava cultivar KU50, the most widely grown cultivar for non-food purposes is susceptible to Sri Lankan cassava mosaic virus (SLCMV). The objective of this work was to engineer resistance to SLCMV by RNA interference (RNAi) in order to increase biomass yield, an important aspect for bioethanol production. Here, we produced transgenic KU50 lines expressing dsRNA homologous to the region between the AV2 and AV1 of DNA A of SLCMV. High level expression of dsRNA of SLCMV did not induce any growth abnormality in the transgenic plants. Transgenic lines displayed high levels of resistance to SLCMV compared to the wild-type plants and no virus load could be detected in uninoculated new leaves of the infected resistant lines after PCR amplification and RT-PCR analysis. The agronomic performance of the transgenic lines was unimpaired after inoculation with the virus as the plants presented similar growth when compared to the mock inoculated control plants and revealed no apparent reduction in the amount and weight of tubers produced. We show that the resistance is correlated with post-transcriptional gene silencing because of the production of transgene specific siRNA. The results demonstrate that transgenic lines exhibited high levels of resistance to SLCMV. This resistance coupled with the desirable yield components in the transgenic lines makes them better candidates for exploitation in the production of biomass as well as bioethanol.

  18. Research Progress on the Comprehensive Utilization of Cassava Waste%木薯废弃物综合利用研究进展

    Institute of Scientific and Technical Information of China (English)

    刘倩; 刘光华; 李月仙; 严炜; 娄予强; 郭容琦; 张林辉; 段春芳

    2012-01-01

    木薯在种植、收获、加工过程中会产生木薯叶、木薯杆、木薯渣、术薯皮等废弃物,其中,木薯叶可食用、饲用;木薯杆、小薯渣均可作为栽培食用菌的基质,木薯杆还可粉碎还田作为肥料,木薯渣也可生产肥料、饲料、沼气:木薯皮则能制成表面活性炭或作为有机生态无土栽培的主要基质。%Cassava waste materials such as cassava leaf, cassava stem, cassava bagasse, cassava bark, etc. resulted from cassava planting, harvesting and processing. Comprehensive utilization of cassava waste materials was discussed in this paper. Cassava leaf can be used for food and feed. Cassava stem, cassava bagasse can be used for matrix of cultivating edible fungi. Crushed cassava stem also can be used as fertilizer. Fertilizer, feed and biogas can be produced from cassava bagasse. Cassava bark can be used for surface active carbon and matrix of eco-organic type soiUess culture system.

  19. Physicochemical properties of cassava starch oxidized by sodium hypochlorite.

    Science.gov (United States)

    Garrido, Lúcia Helena; Schnitzler, Egon; Zortéa, Manoela Estefânea Boff; de Souza Rocha, Thaís; Demiate, Ivo Mottin

    2014-10-01

    In this work, cassava starch was modified by treatment with sodium hypochlorite (NaClO) at different concentrations (0.8, 2.0 and 5.0 % of active chlorine) and selected physicochemical properties of the oxidized starches were investigated. The native and modified samples were evaluated considering moisture, carboxyl content, apparent viscosity, susceptibility to syneresis, mid-infrared spectroscopy and crystallinity index. The treatment with NaClO resulted in alterations in carboxyl content of the oxidized starches that increased with increasing concentration of the oxidant. Oxidized starches also showed higher susceptibility to syneresis, as assessed by the release of liquid during freezing and thawing. Apparent viscosity analysis showed decrease in peak viscosity of the oxidized starches. X-ray diffractograms showed that the oxidation influenced the extent of cassava starch relative crystallinity found to lie between 34.4 % (native) and 39.9 % (2.0 % active chlorine). The infrared spectra are sensitive to structural changes on starch macromolecules and presented characteristic peaks as C-O-C of the six carbon glucose ring absorbs at 1,150-1,085 cm(-1) and due to axial deformation these bands changed with the crystal structure of the starch samples.

  20. Cassava root meal as substitute for maize in layers ration

    Directory of Open Access Journals (Sweden)

    M Anaeto

    2011-06-01

    Full Text Available The effect of replacing maize with graded levels of cassava root meal (CRM as energy source in the diet of laying hens was evaluated during the eight weeks of feeding experiment on performance and cost benefits on layers. Forty-five Nera black laying hens of 24 weeks of age were allocated to five dietary treatments, with nine birds per treatment in a completely randomized design. CRM was used to formulate the diets at 0, 25, 50, 75, and 100%. The result showed that the feed intake of birds in the control group was significantly (p<0.05 different from those fed the CRM diets. The average weight gain of layers receiving up to 50% CRM was similar to the control birds, but significantly different from layers fed 75 and 100% CRM. No mortality was recorded. Egg production per hen per day and average egg weight were significantly different (p<0.05 for birds consuming more than 50% CRM in T4 and T5. Layer feed ration was made cheaper by the replacement of maize with cassava root meal in the diets.

  1. Local domestication of lactic acid bacteria via cassava beer fermentation

    Directory of Open Access Journals (Sweden)

    Alese M. Colehour

    2014-07-01

    Full Text Available Cassava beer, or chicha, is typically consumed daily by the indigenous Shuar people of the Ecuadorian Amazon. This traditional beverage made from cassava tuber (Manihot esculenta is thought to improve nutritional quality and flavor while extending shelf life in a tropical climate. Bacteria responsible for chicha fermentation could be a source of microbes for the human microbiome, but little is known regarding the microbiology of chicha. We investigated bacterial community composition of chicha batches using Illumina high-throughput sequencing. Fermented chicha samples were collected from seven Shuar households in two neighboring villages in the Morona-Santiago region of Ecuador, and the composition of the bacterial communities within each chicha sample was determined by sequencing a region of the 16S ribosomal gene. Members of the genus Lactobacillus dominated all samples. Significantly greater phylogenetic similarity was observed among chicha samples taken within a village than those from different villages. Community composition varied among chicha samples, even those separated by short geographic distances, suggesting that ecological and/or evolutionary processes, including human-mediated factors, may be responsible for creating locally distinct ferments. Our results add to evidence from other fermentation systems suggesting that traditional fermentation may be a form of domestication, providing endemic beneficial inocula for consumers, but additional research is needed to identify the mechanisms and extent of microbial dispersal.

  2. Local domestication of lactic acid bacteria via cassava beer fermentation.

    Science.gov (United States)

    Colehour, Alese M; Meadow, James F; Liebert, Melissa A; Cepon-Robins, Tara J; Gildner, Theresa E; Urlacher, Samuel S; Bohannan, Brendan J M; Snodgrass, J Josh; Sugiyama, Lawrence S

    2014-01-01

    Cassava beer, or chicha, is typically consumed daily by the indigenous Shuar people of the Ecuadorian Amazon. This traditional beverage made from cassava tuber (Manihot esculenta) is thought to improve nutritional quality and flavor while extending shelf life in a tropical climate. Bacteria responsible for chicha fermentation could be a source of microbes for the human microbiome, but little is known regarding the microbiology of chicha. We investigated bacterial community composition of chicha batches using Illumina high-throughput sequencing. Fermented chicha samples were collected from seven Shuar households in two neighboring villages in the Morona-Santiago region of Ecuador, and the composition of the bacterial communities within each chicha sample was determined by sequencing a region of the 16S ribosomal gene. Members of the genus Lactobacillus dominated all samples. Significantly greater phylogenetic similarity was observed among chicha samples taken within a village than those from different villages. Community composition varied among chicha samples, even those separated by short geographic distances, suggesting that ecological and/or evolutionary processes, including human-mediated factors, may be responsible for creating locally distinct ferments. Our results add to evidence from other fermentation systems suggesting that traditional fermentation may be a form of domestication, providing endemic beneficial inocula for consumers, but additional research is needed to identify the mechanisms and extent of microbial dispersal.

  3. Local domestication of lactic acid bacteria via cassava beer fermentation.

    Science.gov (United States)

    Colehour, Alese M; Meadow, James F; Liebert, Melissa A; Cepon-Robins, Tara J; Gildner, Theresa E; Urlacher, Samuel S; Bohannan, Brendan J M; Snodgrass, J Josh; Sugiyama, Lawrence S

    2014-01-01

    Cassava beer, or chicha, is typically consumed daily by the indigenous Shuar people of the Ecuadorian Amazon. This traditional beverage made from cassava tuber (Manihot esculenta) is thought to improve nutritional quality and flavor while extending shelf life in a tropical climate. Bacteria responsible for chicha fermentation could be a source of microbes for the human microbiome, but little is known regarding the microbiology of chicha. We investigated bacterial community composition of chicha batches using Illumina high-throughput sequencing. Fermented chicha samples were collected from seven Shuar households in two neighboring villages in the Morona-Santiago region of Ecuador, and the composition of the bacterial communities within each chicha sample was determined by sequencing a region of the 16S ribosomal gene. Members of the genus Lactobacillus dominated all samples. Significantly greater phylogenetic similarity was observed among chicha samples taken within a village than those from different villages. Community composition varied among chicha samples, even those separated by short geographic distances, suggesting that ecological and/or evolutionary processes, including human-mediated factors, may be responsible for creating locally distinct ferments. Our results add to evidence from other fermentation systems suggesting that traditional fermentation may be a form of domestication, providing endemic beneficial inocula for consumers, but additional research is needed to identify the mechanisms and extent of microbial dispersal. PMID:25071997

  4. Biofuels and Biotechnology: Cassava (Manihot esculenta) as a Research Model

    International Nuclear Information System (INIS)

    Fuels such as ethanol and biodiesel, obtained from plants and their constituents, have recently received the world's attention as a true alternative to the global energy supply, mainly because they are cheaper and less contaminant of the environment than the currently used, non-renewable fossil fuels. Due to the pushing biofuel market, the world is currently experiencing an increase of agricultural land devoted to grow crops used to obtain them, like maize and sugar cane, as well as crops that have the potential to become new sources of biofuels. Similarly, this emerging market is boosting the basic research oriented towards obtaining better quality and yield in these crops. Plants that store high quantities of starch, simple sugars or oils, are the target of the biofuel industry, although the newest technologies use also cellulose as raw material to produce fuels. Cassava (Manihot esculenta) is widely grown in the tropics and constitutes a staple food for approximately 10% of the world population. The high starch content of its storage roots, together with the use of conventional and non-conventional breeding turn this crop into an option to obtain better adapted varieties for ethanol production. This manuscript reviews the current state of biofuels worldwide and at the national level,and discusses the benefits and challenges faced in terms of effect on the environment and the human food chain. Finally, it discusses the potential of cassava as a source of raw material for obtaining biofuels in Colombia.

  5. Biofuels and Biotechnology: Cassava (Manihot esculenta) as a Research Model

    International Nuclear Information System (INIS)

    Fuels such as ethanol and biodiesel, obtained from plants and their constituents, have recently received the world's attention as a true alternative to the global energy supply, mainly because they are cheaper and less contaminant of the environment than the currently used, non-renewable fossil fuels. Due to the pushing biofuel market, the world is currently experiencing an increase of agricultural land devoted to grow crops used to obtain them, like maize and sugar cane, as well as crops that have the potential to become new sources of biofuels. Similarly, this emerging market is boosting the basic research oriented towards obtaining better quality and yield in these crops. Plants that store high quantities of starch, simple sugars or oils, are the target of the biofuel industry, although the newest technologies use also cellulose as raw material to produce fuels. Cassava (Manihot esculenta) is widely grown in the tropics and constitutes a staple food for approximately 10% of the world population. The high starch content of its storage roots, together with the use of conventional and non-conventional breeding turn this crop into an option to obtain better adapted varieties for ethanol production. This manuscrip reviews the current state of biofuels worldwide and at the national level, and discusses the benefits and challenges faced in terms of effect on the environment and the human food chain. Finally, it discusses the potential of cassava as a source of raw material for obtaining biofuels in Colombia.

  6. Hepatic Necrosis and Degenerative Myopathy Associated with Cassava Feeding in Pigs

    Directory of Open Access Journals (Sweden)

    Gloria Daniel-Igwe

    2014-01-01

    Full Text Available Forty-three deaths were recorded among pigs fed boiled cassava meal at a private piggery over a period of two years. There were signs of sudden death in some cases with blood exuding from the external nares, vomiting, muscular weakness and pain or reluctance to move, emaciation, and stunted growth. The necropsy lesions included skeletal and cardiac muscle degeneration and necrosis, icterus, hepatic necrosis, and oedema of the dependent parts. The deaths and clinical signs are thought to be due to a non cyanide toxic principle in cassava, possibly the coumarins (scopoletin, which is found in high levels in cassava diet even after heat treatment. Therefore, the use of proper processing technology to obtain cassava products of high quality is recommended.

  7. Application of thermophilic enzymes and water jet system to cassava pulp.

    Science.gov (United States)

    Chaikaew, Siriporn; Maeno, Yuka; Visessanguan, Wonnop; Ogura, Kota; Sugino, Gaku; Lee, Seung-Hwan; Ishikawa, Kazuhiko

    2012-12-01

    Co-production of fermentable sugars and nanofibrillated cellulose from cassava pulp was achieved by the combination of thermophilic enzymes (endoglucanase, β-glucosidase, and α-amylase) and a new atomization system (Star Burst System; SBS), which employs opposing water jets. The SBS represents a key technology for providing cellulose nanofibers and improving the enzymatic saccharification of cassava pulp. Depending on the enzymes used, the production of glucose from cassava pulp treated with the SBS was 1.2- to 2.5-fold higher than that from pulp not treated with the SBS. Nanofibrillated cellulose with the gel-like property in suspension was produced (yield was over 90%) by α-amylase treatment, which completely released trapped starch granules from the fibrous cell wall structure of cassava pulp pretreated with the SBS. The SBS provides an environmentally low-impact pretreatment system for processing biomass material into value-added products. PMID:23073093

  8. CONTRIBUTIONS OF MICROFINANCE INSTITUTIONS TO ECONOMIC EFFICIENCY OF CASSAVA FARMERS IN ABIA STATE, NIGERIA

    Directory of Open Access Journals (Sweden)

    Kingsley Chukwuemeka OBIKE

    2014-10-01

    Full Text Available The study examined contributions of microfinance institutions to economic efficiency of cassava farmers in Abia state, Nigeria. A multistage random sampling technique was adopted in collecting cross sectional data on a sample size of 240 respondents (120 MFI beneficiaries and 120 non beneficiaries. Primary Data was collected by administering questionnaire on cassava farmers. The result showed that economic efficiency of MFI beneficiaries was influenced by wage rate, price of fertilizer and adjusted Y (output, while wage rate, price of fertilizer and price of cassava cutting s are variables that influenced economic efficiency of non beneficiaries. The t – test analysis confirmed that MFI beneficiaries had higher economic efficiency advantage compared with non beneficiaries. It is recommended that government agricultural policy should take positive steps to reduce interest rate to encourage MFI efforts in providing the necessary platform to encourage higher efficiency in cassava production in Abia state, Nigeria.

  9. Transient GUS gene expression in cassava (Manihot esculenta Crantz using Agrobacterium tumefaciens leaf infiltration

    Directory of Open Access Journals (Sweden)

    Paula Díaz T.

    2014-09-01

    Full Text Available Objective. Assess transient gene expression of GUS in cassava (Manihot esculenta Crantz leaves using Agrobacterium tumefaciens infiltration. Materials and methods. A. tumefaciens strains GV3101 and AGL1 containing pCAMBIA1305.2 were used to evaluate transient gene expression of β-glucuronidase (GUS. A. tumefaciens infiltration (agroinfiltration was made using both leaves from in vitro and 1 month old greenhouse plants. Leaves were incubated in X-GLUC buffer, stained and photographed to detect GUS activity. Results. Agroinfiltration assays showed GUS transient expression in leaves of cassava varieties widely cultivated in the north coast and eastern savannah, MCOL2215 (Venezuelan and CM6438-14 (Vergara, respectively. A. tumefaciens agressive strain AGL1 showed high efficiency inducing GUS expression in cassava leaves. Conclusions. We recommend using A. tumefaciens agressive strain AGL1 for agroinfiltration to assess transient expression in cassava leaves.

  10. Mild method for removal of cyanogens from cassava leaves with retention of vitamins and protein.

    Science.gov (United States)

    Bradbury, J Howard; Denton, Ian C

    2014-09-01

    A mild method was developed to remove cyanogens from cassava leaves that involved three consecutive steps (1) pounding, (2) standing for 2h in the sun or 5h in the shade in the tropics and (3) washing three times in water. Four cassava cultivars were used and the mean residual total cyanide content after steps 1, 2 and 3 was 28%, 12% and 1%, respectively. The pounded cassava leaves retained their bright green colour and texture. The traditional method for removing cyanogens from pounded cassava leaves is by boiling in water which removed all cyanogens in 10 min. However this method caused the pounded leaves to become dull green in colour and would cause considerable losses of vitamins, protein and methionine, which are already in short supply in the diet of poor village people in tropical Africa.

  11. Molecular and supra-molecular structure of waxy starches developed from cassava (Manihot esculenta Crantz).

    Science.gov (United States)

    Rolland-Sabaté, Agnès; Sanchez, Teresa; Buléon, Alain; Colonna, Paul; Ceballos, Hernan; Zhao, Shan-Shan; Zhang, Peng; Dufour, Dominique

    2013-02-15

    The aim of this work was to characterize the amylopectin of low amylose content cassava starches obtained from transgenesis comparatively with a natural waxy cassava starch (WXN) discovered recently in CIAT (International Center for Tropical Agriculture). Macromolecular features, starch granule morphology, crystallinity and thermal properties of these starches were determined. M¯(w) of amylopectin from the transgenic varieties are lower than WXN. Branched and debranched chain distributions analyses revealed slight differences in the branching degree and structure of these amylopectins, principally on DP 6-9 and DP>37. For the first time, a deep structural characterization of a series of transgenic lines of waxy cassava was carried out and the link between structural features and the mutated gene expression approached. The transgenesis allows to silenced partially or totally the GBSSI, without changing deeply the starch granule ultrastructure and allows to produce clones with similar amylopectin as parental cassava clone.

  12. Application of pure strains to standardize the acidification process and the amylolytic activity in cassava fermentation

    International Nuclear Information System (INIS)

    The report describes some aspects of the optimization of the traditional fermentation of cassava and potential role of the acidification process in the development of microflora at the different stages of the fermentation. It was shown that the inoculation of the cassava fermenting pulp by pure cultures of lactic acid bacteria such as Lactobacillus cellobiosus and L. plantarum had resulted in sufficient acceleration of the fermentation process and the desired condition of the fermented end-product could reach in 7-24 hours instead of 72 hours (natural fermentation). The effects similar to these were obtained in the experiments on inoculation of cassava with the fermented mass (or with drained liquor) from the previous bath. The optimal condition for the exhibition of the amylolytic activity in fresh cassava was: pH 6,0 at 40 deg. C, out of this range the activity falls down sharply. (author). 22 figs, 3 tabs

  13. Perception of Infestation Problems on Cassava Farms and Preference for Weed Management Practices in Humid Agro- Ecological Zone of Nigeria

    OpenAIRE

    Anthony Agumagu; Olufemi Martins Adesope; Edna Chioma Matthews-Njoku

    2008-01-01

    The problem of weed infestation on cassava farms is a major factor for low crop yield. This problem has caused untold hardship on the small-scale cassava farms where production at the subsistence level and where farmers still manage to produce some quantity for sale. The study examines cassava farmers’ perception of problems of infestation and preference for weed management practices in the humid agro-ecological zone of Nigeria. Data was collected with the aid of questionnaire and interviews....

  14. Field testing and exploitation of genetically modified cassava with low-amylose or amylose-free starch in Indonesia

    OpenAIRE

    Koehorst-van Putten, H. J. J.; Sudarmonowati, E.; Herman, M; Pereira-Bertram, I. J.; Wolters, A. M. A.; Meima, H.; Vetten, de, N.; Raemakers, C.J.J.M.; Visser, R. G. F.

    2012-01-01

    The development and testing in the field of genetically modified -so called- orphan crops like cassava in tropical countries is still in its infancy, despite the fact that cassava is not only used for food and feed but is also an important industrial crop. As traditional breeding of cassava is difficult (allodiploid, vegetatively propagated, outbreeding species) it is an ideal crop for improvement through genetic modification. We here report on the results of production and field testing of g...

  15. Biological implications in cassava for the production of amylose-free starch: impact on root yield and related traits.

    OpenAIRE

    Amanda eKarlström; Sandra eSalazar; Fernando eCalle; Nelson eMorante; Dominique eDufour; Hernán eCeballos

    2016-01-01

    Cassava (Manihot esculenta, Crantz) is an important food security crop, but it is becoming an important raw material for different industrial applications. Cassava is the second most important source of starch worldwide. Novel starch properties are of interest to the starch industry, and one them is the recently identified amylose-free (waxy) cassava starch. Waxy mutants have been found in different crops and have been often associated with a yield penalty. There are ongoing efforts to develo...

  16. Biological Implications in Cassava for the Production of Amylose-Free Starch: Impact on Root Yield and Related Traits

    OpenAIRE

    Karlström, Amanda; Calle, Fernando; Salazar, Sandra; Morante, Nelson; Dufour, Dominique; Ceballos, Hernán

    2016-01-01

    Cassava (Manihot esculenta, Crantz) is an important food security crop, but it is becoming an important raw material for different industrial applications. Cassava is the second most important source of starch worldwide. Novel starch properties are of interest to the starch industry, and one them is the recently identified amylose-free (waxy) cassava starch. Waxy mutants have been found in different crops and have been often associated with a yield penalty. There are ongoing efforts to develo...

  17. Softening and Mineral Content of Cassava (Manihot esculenta Crantz) Leaves During the Fermentation to Produce Ntoba mbodi

    OpenAIRE

    S. Mokemiabeka; J. Dhellot; S.C. Kobawila; P. Diakabana; R.N. Ntietie Loukombo; A.G. Nyanga-Koumou; D. Louembe

    2011-01-01

    The aim of study is to investigate the softening of cassava leaves during the fermentation of Ntoba mbodi and the mineral content of cassava leaves fermented and unfermented. The softening of cassava leaves is a characteristic of fermentation to produce Ntoba mbodi. It is due to an enzymatic process. The activity of cellulase and polygalacturonase enzymes, very weak at the beginning of fermentation, increases sharply in 24 h and decreases thereafter. The pectinesterase and pectin lyase activi...

  18. Determinants Of Export-Led Cassava Production Intensification Among Small-Holder Farmers in Delta State, Nigeria

    OpenAIRE

    Achoja, F. O.; Idoge, D. E.; Ukwuaba, S. I.; Esowhode, A.E.

    2012-01-01

    Determinants of export-led cassava production intensification among small-holder farmers were investigated. Primary data collected with structured questionnaire from randomly selected 60 respondents, were analysed using appropriate statistics. The result showed a slow increasing trend in response to export opportunities. Farm size, credit availability, cassava product domestic prices, labour and frequency of extension contact had positive effect on cassava output while existence of efficient ...

  19. Developing GM super cassava for improved health and food security: future challenges in Africa

    OpenAIRE

    Adenle Ademola A; Aworh Ogugua C; Akromah Richard; Parayil Govindan

    2012-01-01

    Abstract Background There is an urgent need to solve the problem of micronutrient malnutrition that is prevalent among young children and women in Africa. Genetically modified (GM) biofortified cassava has great potential to solve part of this problem, but controversy surrounding GM technology and lack of awareness, limited facilities, biased news and other factors may hinder the adoption of GM cassava in the future. Method Using semi-structured interviews in Ghana and Nigeria, this paper exa...

  20. Physicochemical and microbiological characterization of cassava flower honey samples produced by africanized honeybees

    OpenAIRE

    Lucimar Peres de Moura Pontara; Edmar Clemente; Dalany Menezes Oliveira; Angela Kwiatkowski; Cássia Inês Lourenzi Franco Rosa; Valter Eugênio Saia

    2012-01-01

    Cassava producers in the region of Marília-São Paulo are integrating their farming activity with beekeeping to diversify their income. The aim of this study was to evaluate the physicochemical and microbiological quality of honey samples produced by Africanized honeybees Apis mellifera from cassava flower in 2008. Analysis were carried out for pH, total soluble solids (TSS), acidity, moisture, reducing and total sugars, apparent sucrose, hydroxymethylfurfural, color, ash, proteins, water inso...

  1. In vitro degradation of linamarin by microorganisms isolated from cassava wastewater treatment lagoons

    Directory of Open Access Journals (Sweden)

    S. P Vasconcellos

    2009-12-01

    Full Text Available This study aimed at isolating and characterizing of microorganisms able to use linamarin as sole carbon source. Thirty one microbial strains were isolated from manipueira, a liquid effluent of cassava processing factories. Among these strains, Bacillus licheniformis (isolate 2_2 and Rhodotorulla glutinis (isolate L1 were able to degrade 71% and 95% of added linamarin, respectively, within 7 days, showing high biodegradation activity and great potential for detoxification of cassava processing wastewaters.

  2. Effect of carboxymethyl cellulose concentration on physical properties of biodegradable cassava starch-based films

    Directory of Open Access Journals (Sweden)

    Sriburi Pensiri

    2011-02-01

    Full Text Available Abstract Background Cassava starch, the economically important agricultural commodity in Thailand, can readily be cast into films. However, the cassava starch film is brittle and weak, leading to inadequate mechanical properties. The properties of starch film can be improved by adding plasticizers and blending with the other biopolymers. Results Cassava starch (5%w/v based films plasticized with glycerol (30 g/100 g starch were characterized with respect to the effect of carboxymethyl cellulose (CMC concentrations (0, 10, 20, 30 and 40%w/w total solid and relative humidity (34 and 54%RH on the mechanical properties of the films. Additionally, intermolecular interactions were determined by Fourier transform infrared spectroscopy (FT-IR, melting temperature by differential scanning calorimetry (DSC, and morphology by scanning electron microscopy (SEM. Water solubility of the films was also determined. Increasing concentration of CMC increased tensile strength, reduced elongation at break, and decreased water solubility of the blended films. FT-IR spectra indicated intermolecular interactions between cassava starch and CMC in blended films by shifting of carboxyl (C = O and OH groups. DSC thermograms and SEM micrographs confirmed homogeneity of cassava starch-CMC films. Conclusion The addition of CMC to the cassava starch films increased tensile strength and reduced elongation at break of the blended films. This was ascribed to the good interaction between cassava starch and CMC. Cassava starch-CMC composite films have the potential to replace conventional packaging, and the films developed in this work are suggested to be suitable for low moisture food and pharmaceutical products.

  3. Cassava Processing and Marketing by Rural Women in the Central Region of Cameroon

    OpenAIRE

    SHIOYA, Akiyo

    2013-01-01

    This study examines the development of rural women's commercial activities in Central Cameroon, particularly the Department of Lekié, which is adjacent to Yaoundé, the capital of Cameroon. I focused on cassava processing technologies and the sale of cassavabased processed foods undertaken by women in a suburban farming village. Cassava is one of the main staple foods in central Cameroon, including in urban areas. One of its characteristics is that it keeps for a long period in the ground but ...

  4. Enzyme Activities and Substrate Degradation by Fungal Isolates on Cassava Waste During Solid State Fermentation

    OpenAIRE

    Pothiraj, C.; Eyini, M.

    2007-01-01

    The growth and bioconversion potential of selected strains growing on cassava waste substrate during solid state fermentation were assessed. Rhizopus stolonifer showed the highest and the fastest utilization of starch and cellulose in the cassava waste substrate. It showed 70% starch utilization and 81% cellulose utilization within eight days. The release of reducing sugars indicating the substrate saccharification or degradation potential of the organisms reached the highest value of 406.5 m...

  5. Effect of the improved fermentation on physicochemical properties and sensorial acceptability of sour cassava starch

    OpenAIRE

    Maria Janete Angeloni Marcon; Gisele Cristina Netto Vieira; Karina Nunes de Simas; Karina Santos; Manoela Alano Vieira; Renata Dias de Mello Castanho Amboni; Edna Regina Amante

    2007-01-01

    The aim of this work was to study the effect of improved fermentation on sour cassava starch, aiming to reduce its fermentation time and to enhance its expansion capacity as well as its viscoamylographic properties and its sensorial acceptability. Results showed that the improved process of cassava starch production did not harm starch expansion, physicochemical properties or sensorial acceptability; it also produced starches with different viscoamylographic properties, which compared favoura...

  6. Factors affecting the relative competitiveness of cassava production in southwestern Trinidad

    OpenAIRE

    Patterson-Andrews, Hazel; Pemberton, Carlisle

    2010-01-01

    This study sought to determine the factors affecting the relative competitiveness (RC) measured as the normalized profit per acre, of cassava farmers in South Western Trinidad through a determination of the factors affecting the mean and variance of the RC inefficiency term of the farmers. A sample of 112 small farmers growing cassava as their main crop provided the data for the study. A normalized translog stochastic RC frontier model was estimated. The model also determined the factors affe...

  7. Determinants of profitability among small scale cassava processors in South Western Nigeria

    OpenAIRE

    EHINMOWO O.O.; AFOLABI J.A.; FATUASE A.I.

    2015-01-01

    This study empirically analyzed the determinants of profitability among small scale cassava processors in Southwest, Nigeria. Three States were considered for the study which was Ogun, Oyo and Ondo. A multistage sampling technique was employed to randomly select 373 respondents. The data collected were analyzed using descriptive statistics and multiple regression models. The findings revealed that the cassava processing business was profitable in the study area given the value of gross margin...

  8. Characteristics of cassava starch fermentation wastewater based on structural degradation of starch granules

    OpenAIRE

    Juliane Mascarenhas Pereira; Ana Carolina Moura de Sena Aquino; Daiana Cardoso de Oliveira; Gabriela Rocha; Alícia de Francisco; Pedro Luiz Manique Barreto; Edna Regina Amante

    2016-01-01

    ABSTRACT: Sour cassava starch is a naturally modified starch produced by fermentation and sun drying, achieving the property of expansion upon baking. Sour cassava starch' bakery products can be prepared without the addition of yeast and it is gluten free. The fermentation process associated with this product has been well studied, but the wastewater, with high acidity and richness in other organic compounds derived from starch degradation, requires further investigation. In this study, the s...

  9. Toxic effects of prolonged administration of leaves of cassava (Manihot esculenta Crantz) to goats.

    Science.gov (United States)

    Soto-Blanco, Benito; Górniak, Silvana Lima

    2010-07-01

    Cassava (Manihot esculenta Crantz) is a major source of dietary energy for humans and domestic animals in many tropical countries. However, consumption of cassava is limited by its characteristic content of cyanogenic glycosides. The present work aimed to evaluate the toxic effects of ingestion of cassava leaves by goats for 30 consecutive days, and to compare the results with the toxic effects of cyanide in goats, which have been described previously. Eight Alpine cross-bred female goats were divided into two equal groups, and were treated with ground frozen cassava leaves at a target dose of 6.0mg hydrogen cyanide (HCN)/kg/day (treated animals), or with ground hay and water only (control group) by gavage for 30 consecutive days. Blood samples were collected on days 0, 7, 15, 21, and 30 for biochemical panel and cyanide determination. At the end of the experiment, fragments of pancreas, thyroid gland, liver, kidney, lungs, heart, spleen, and the whole central nervous system were collected for histopathological examination. Clinical signs were observed in all goats treated with cassava on the first day of the experiment. From the second day the dose of cassava leaves was reduced to 4.5mgHCN/kg/day. No changes were found in the blood chemical panel. A mild increase in the number of resorption vacuoles in the thyroid follicular colloid, slight vacuolation of periportal hepatocytes, and spongiosis of the mesencephalon were found in goats treated with cassava. The pattern of lesions seen in the present goats was similar to what has been described previously in cyanide-dosed goats. Thus, the toxic effects of the ingestion of cassava leaves by goats can be attributed to the action of cyanide released from cyanogenic glycosides, and none of the effects was promoted by these glycosides directly.

  10. Effects of sweet cassava polysaccharide extracts on endurance exercise in rats

    OpenAIRE

    Yen, Chia Hung; Tsao, Te Hung; Huang, Cheng Uan; Yang, Chang Bin; Kuo, Chung Sheng

    2013-01-01

    Background Sweet cassava tubers have abundant carbohydrates consisting of monosaccharides and polysaccharides. In addition, polysaccharides extracted from plants improve sports performance, according to recent studies. We therefore examined whether the administration of sweet cassava polysaccharides (SCPs) benefited endurance performance in rats Methods Male Sprague–Dawley rats (n = 30, 7 weeks old) were divided into three groups: control (C), exercise (Ex), and exercise plus SCPs administrat...

  11. Radiosensitivity of the reproductive organs exposed to the flow of cassava mixed neutron/gamma

    International Nuclear Information System (INIS)

    A preliminary study of seeds and cuttings radiosensitivity for Cassava mutation breeding was performed. Three Cassava clones were irradiated at different times morder to determine the maximum mutagenic treatment. Data obtained show that treatments of which irradiated time is greater than 6 seconds are lethals for cutting regeneration. Duration inferior or equal to 6 seconds have no negative effect. The cutting regeneration is maximum for 3 seconds treatment and decreases with irradiation time. For irradiated seeds, germination has been completely inhibited.

  12. Technical Efficiency Analysis of Nigerian Cassava Farmers: A Guide for Food Security Policy

    OpenAIRE

    B.C. Asogwa; Umeh, Joseph Chinedu; P.I. Ater

    2006-01-01

    This study analyzed relationship between techn ical efficiency and socio-economic variables of cassava farmers in Nigeria. Data were collected from randomly sampled 360 cassava farmers in Nigeria using a structured questionnaire. The data were analyzed using descriptive statistics comprising mean, minimum value, maximum value and standard deviation, as well as inferential statistics, which comprised correlation and regression. The findings of the s tudy indicated that a significant relationsh...

  13. Molecular genetic tools to modulate post-harvest physiology in cassava

    International Nuclear Information System (INIS)

    Within 24-72 hours of harvest the starchy storage roots of cassava deteriorate rapidly depending on variety and environmental conditions. This post-harvest physiological deterioration (PPD) necessitates their prompt consumption or processing. In traditional village society, cassava roots are left in the ground until required; but, with increased urbanisation and the entry of cassava into the cash economy, distances have increased and PPD has become a major constraint to the development of this important crop, which impacts on farmers, processors and consumers alike. Improvement of cassava with respect to its PPD response via breeding is fraught with difficulties due to the high heterozygosity of the crop, a strong association between PPD and high dry matter content, and a high genetic X environment interaction. Molecular genetic tools may offer alternative approaches via insights into the PPD response itself, the provision of molecular markers for use in marker assisted selection and via the direct manipulation of the cassava genome. cDNA microarrays identify 73 genes whose expression changes significantly during the time-course of PPD; these clones are available to the cassava community for mapping or other research. These data support the hypothesis that reactive oxygen species mediated programmed cell death is at the heart of the PPD response. Currently we are further testing this hypothesis through the genetic modification of cassava using genes with the ability to alter the reactive oxygen defence status of the roots or to enhance the root's antiprogrammed cell death response. These modifications have the potential to extend the shelf-life of the cassava roots and ultimately to benefit resource-poor farmers. (author)

  14. Microbiological and biochemical characterization of cassava retting, a traditional lactic Acid fermentation for foo-foo (cassava flour) production.

    Science.gov (United States)

    Brauman, A; Keleke, S; Malonga, M; Miambi, E; Ampe, F

    1996-08-01

    The overall kinetics of retting, a spontaneous fermentation of cassava roots performed in central Africa, was investigated in terms of microbial-population evolution and biochemical and physicochemical parameters. During the traditional process, endogenous cyanogens were almost totally degraded, plant cell walls were lysed by the simultaneous action of pectin methylesterase and pectate lyase, and organic acids (C(inf2) to C(inf4)) were produced. Most microorganisms identified were found to be facultative anaerobes which used the sugars (sucrose, glucose, and fructose) present in the roots as carbon sources. After 24 h of retting, the fermentation reached an equilibrium that was reproducible in all the spontaneous fermentations studied. Lactic acid bacteria were largely predominant (over 99% of the total flora after 48 h) and governed the fermentation. The epiphytic flora was first replaced by Lactococcus lactis, then by Leuconostoc mesenteroides, and finally, at the end of the process, by Lactobacillus plantarum. These organisms produced ethanol and high concentrations of lactate, which strongly acidified the retting juice. In addition, the rapid decrease in partial oxygen pressure rendered the process anaerobic. Strict anaerobes, such as Clostridium spp., developed and produced the volatile fatty acids (mainly butyrate) responsible, together with lactate, for the typical flavor of retted cassava. Yeasts (mostly Candida spp.) did not seem to play a significant role in the process, but their increasing numbers in the last stage of the process might influence the flavor and the preservation of the end products. PMID:16535378

  15. Comparison of leaf proteomes of cassava (Manihot esculenta Crantz cultivar NZ199 diploid and autotetraploid genotypes.

    Directory of Open Access Journals (Sweden)

    Feifei An

    Full Text Available Cassava polyploid breeding has drastically improved our knowledge on increasing root yield and its significant tolerance to stresses. In polyploid cassava plants, increases in DNA content highly affect cell volumes and anatomical structures. However, the mechanism of this effect is poorly understood. The purpose of the present study was to compare and validate the changes between cassava cultivar NZ199 diploid and autotetraploid at proteomic levels. The results showed that leaf proteome of cassava cultivar NZ199 diploid was clearly differentiated from its autotetraploid genotype using 2-DE combined MS technique. Sixty-five differential protein spots were seen in 2-DE image of autotetraploid genotype in comparison with that of diploid. Fifty-two proteins were identified by MALDI-TOF-MS/MS, of which 47 were up-regulated and 5 were down-regulated in autotetraploid genotype compared with diploid genotype. The classified functions of 32 up-regulated proteins were associated with photosynthesis, defense system, hydrocyanic acid (HCN metabolism, protein biosynthesis, chaperones, amino acid metabolism and signal transduction. The remarkable variation in photosynthetic activity, HCN content and resistance to salt stress between diploid and autotetraploid genotypes is closely linked with expression levels of proteomic profiles. The analysis of protein interaction networks indicated there are direct interactions between the 15 up-regulation proteins involved in the pathways described above. This work provides an insight into understanding the protein regulation mechanism of cassava polyploid genotype, and gives a clue to improve cassava polyploidy breeding in increasing photosynthesis and resistance efficiencies.

  16. Acid and enzymatic hydrolysis to recover reducing sugars from cassava bagasse: an economic study

    Directory of Open Access Journals (Sweden)

    Woiciechowski Adenise Lorenci

    2002-01-01

    Full Text Available The objective of this work was to study the acid and enzymatic hydrolysis of cassava bagasse for the recovery of reducing sugars and to establish the operational costs. A statistical program "Statistica", based on the surface response was used to optimize the recovery of reducing sugars in both the processes. The process economics was determined considering the values of reducing sugars obtained at laboratory scale, and the operations costs of a cylindrical reactor of 1500 L, with flat walls at the top and bottom. The reactor was operated with 150 kg of cassava bagasse and 1350 kg of water. The yield of the acid hydrolysis was 62.4 g of reducing sugars from 100 g of cassava bagasse containing 66% starch. It represented 94.5% of reducing sugar recovery. The yield of the enzymatic hydrolysis was 77.1 g of reducing sugars from 120 g of cassava bagasse, which represented 97.3% of reducing sugars recovery. Concerning to the time, a batch of acid hydrolysis required 10 minutes, plus the time to heat and cool the reactor, and a batch of the enzymatic hydrolysis needed 25 hours and 20 minutes, plus the time to heat and to cool the reactor. Thus, the acid hydrolysis of 150 kg of cassava bagasse required US$ 34.27, and the enzymatic hydrolysis of the same amount of cassava bagasse required US$ 2470.99.

  17. Beta-carotene from cassava (Manihot esculenta Crantz) leaves improves vitamin A status in rats.

    Science.gov (United States)

    Siqueira, Egle Machado de Almeida; Arruda, Sandra Fernandes; de Vargas, Rodrigo Martins; de Souza, Elizabeth Maria Talá

    2007-01-01

    The bioavailability of beta-carotene from cassava (Manihot esculenta Crantz) leaves was assayed in vitamin A deficient Wistar rats (Rattus norvegicus). Rats were separated into three groups and fed with a modified AIN-93G--vitamin A deficient--diet. Deficient rat received this diet without any additional vitamin A source. Controls received the diet with 7200 microg of synthetic beta-carotene (control), while experimentals (test) received 19.5 g of cassava leaves powder per kg of diet. The cassava leaves with beta-carotene promotes similar growth and tissue weight in rats to the synthetic beta-carotene. The relative bioavailability, estimated as the Retinol Accumulation Factor (RAF), was 16.5 and 27.5 for control and test groups, respectively, indicating that control and test rats should have an intake of 16.5 microg or 27.5 microg of beta-carotene from synthetic form or cassava leaves powder for each 1 microg of hepatic retinol stored, respectively. The cassava leaves beta-carotene bioavailability was lower than the synthetic beta-carotene probably because the beta-carotene from the leaf matrix may be bounded to protein complex or inside organelles, which impair carotenoid absorption. Our findings showed that beside the hepatic retinol recovery, cassava leaf beta-carotene could maintain rat growth and avoid vitamin A deficient symptoms.

  18. Comparison of leaf proteomes of cassava (Manihot esculenta Crantz) cultivar NZ199 diploid and autotetraploid genotypes.

    Science.gov (United States)

    An, Feifei; Fan, Jie; Li, Jun; Li, Qing X; Li, Kaimian; Zhu, Wenli; Wen, Feng; Carvalho, Luiz J C B; Chen, Songbi

    2014-01-01

    Cassava polyploid breeding has drastically improved our knowledge on increasing root yield and its significant tolerance to stresses. In polyploid cassava plants, increases in DNA content highly affect cell volumes and anatomical structures. However, the mechanism of this effect is poorly understood. The purpose of the present study was to compare and validate the changes between cassava cultivar NZ199 diploid and autotetraploid at proteomic levels. The results showed that leaf proteome of cassava cultivar NZ199 diploid was clearly differentiated from its autotetraploid genotype using 2-DE combined MS technique. Sixty-five differential protein spots were seen in 2-DE image of autotetraploid genotype in comparison with that of diploid. Fifty-two proteins were identified by MALDI-TOF-MS/MS, of which 47 were up-regulated and 5 were down-regulated in autotetraploid genotype compared with diploid genotype. The classified functions of 32 up-regulated proteins were associated with photosynthesis, defense system, hydrocyanic acid (HCN) metabolism, protein biosynthesis, chaperones, amino acid metabolism and signal transduction. The remarkable variation in photosynthetic activity, HCN content and resistance to salt stress between diploid and autotetraploid genotypes is closely linked with expression levels of proteomic profiles. The analysis of protein interaction networks indicated there are direct interactions between the 15 up-regulation proteins involved in the pathways described above. This work provides an insight into understanding the protein regulation mechanism of cassava polyploid genotype, and gives a clue to improve cassava polyploidy breeding in increasing photosynthesis and resistance efficiencies.

  19. Biology and management of Bemisia whitefly vectors of cassava virus pandemics in Africa.

    Science.gov (United States)

    Legg, James P; Shirima, Rudolph; Tajebe, Lensa S; Guastella, Devid; Boniface, Simon; Jeremiah, Simon; Nsami, Elibariki; Chikoti, Patrick; Rapisarda, Carmelo

    2014-10-01

    Cassava mosaic disease and cassava brown streak disease are caused by viruses transmitted by Bemisia tabaci and affect approximately half of all cassava plants in Africa, resulting in annual production losses of more than $US 1 billion. A historical and current bias towards virus rather than vector control means that these diseases continue to spread, and high Bemisia populations threaten future virus spread even if the extant strains and species are controlled. Progress has been made in parts of Africa in replicating some of the successes of integrated Bemisia control programmes in the south-western United States. However, these management efforts, which utilise chemical insecticides that conserve the Bemisia natural enemy fauna, are only suitable for commercial agriculture, which presently excludes most cassava cultivation in Africa. Initiatives to strengthen the control of B. tabaci on cassava in Africa need to be aware of this limitation, and to focus primarily on control methods that are cheap, effective, sustainable and readily disseminated, such as host-plant resistance and biological control. A framework based on the application of force multipliers is proposed as a means of prioritising elements of future Bemisia control strategies for cassava in Africa.

  20. Neurotoxic effect of linamarin in rats associated with cassava (Manihot esculenta Crantz) consumption.

    Science.gov (United States)

    Rivadeneyra-Domínguez, Eduardo; Vázquez-Luna, Alma; Rodríguez-Landa, Juan Francisco; Díaz-Sobac, Rafael

    2013-09-01

    Cassava (Manihot esculenta Crantz) is a plant widely used for food consumption in different processed products in rural areas of Africa, Asia, and Latin America. Cassava is a good source of carbohydrates and micronutrients. However, if it is not adequately processed or the consumer has nutritional deficiencies, then its cyanogenic glycoside (i.e., linamarin and lotaustralin) content makes it potentially neurotoxic. In the present study, the neurotoxic effects of different concentrations of linamarin (0.075, 0.15, 0.22, and 0.30 mg/kg) contained in cassava juice were evaluated in the open field and swim tests to identify locomotor alterations in adult male Wistar rats. The linamarin concentration in cassava juice was determined by high-performance liquid chromatography, and the juice was administered intraesophageally for 28 days. The results suggested that the consumption of linamarin in cassava juice increased the number of crossings and rearings in the open field test and caused behavioral deficiency, reflected by lateral swimming, in the swim test on days 21 and 28 of treatment. These alterations are possibly related to neuronal damage caused by linamarin in cassava juice in structures of the central nervous system involved in motor processing.

  1. SSR and EST-SSR-based genetic linkage map of cassava (Manihot esculenta Crantz).

    Science.gov (United States)

    Sraphet, Supajit; Boonchanawiwat, Athipong; Thanyasiriwat, Thanwanit; Boonseng, Opas; Tabata, Satoshi; Sasamoto, Shigemi; Shirasawa, Kenta; Isobe, Sachiko; Lightfoot, David A; Tangphatsornruang, Sithichoke; Triwitayakorn, Kanokporn

    2011-04-01

    Simple sequence repeat (SSR) markers provide a powerful tool for genetic linkage map construction that can be applied for identification of quantitative trait loci (QTL). In this study, a total of 640 new SSR markers were developed from an enriched genomic DNA library of the cassava variety 'Huay Bong 60' and 1,500 novel expressed sequence tag-simple sequence repeat (EST-SSR) loci were developed from the Genbank database. To construct a genetic linkage map of cassava, a 100 F(1) line mapping population was developed from the cross Huay Bong 60 by 'Hanatee'. Polymorphism screening between the parental lines revealed that 199 SSRs and 168 EST-SSRs were identified as novel polymorphic markers. Combining with previously developed SSRs, we report a linkage map consisted of 510 markers encompassing 1,420.3 cM, distributed on 23 linkage groups with a mean distance between markers of 4.54 cM. Comparison analysis of the SSR order on the cassava linkage map and the cassava genome sequences allowed us to locate 284 scaffolds on the genetic map. Although the number of linkage groups reported here revealed that this F(1) genetic linkage map is not yet a saturated map, it encompassed around 88% of the cassava genome indicating that the map was almost complete. Therefore, sufficient markers now exist to encompass most of the genomes and efficiently map traits in cassava.

  2. Cassava leaves in combination with sera onggok and rice bran as supplements in buffaloes ration

    International Nuclear Information System (INIS)

    Two experiments have been undertaken to evaluate the utilization of cassava leaves in combination with sera onggok or rice bran as supplements in buffalo ration under traditional village condition. In experiment 1, 16 buffaloes were divided in four groups, each receiving a different ration ranging from mixed forage alone to mixed forage supplemented with a combination of cassava leaves and sera onggok or rice bran. Changes in dry metter consumption, daily weight gain, feed convertion ratio and incom over feed cost were assesed. Experiments 2 covered an in vitro study on the changes in rumen fermentation as affected by different rations. The results of experiment 1 indicated the lack of differences in dry matter consumption. However, the daily weight gain, feed convertion ratio and income over feed cost (IOFC) higher in animal receiving mixed forage suplement with cassava leaves in combination with either sera onggok or rice bran as compared to those of animal receiving mixed forage or mixed forage supplemented with cassava leaves. Experiment 2 revealed that amonia concentration and volatile fatty acid production were able to support a higher microbil activity supplemented with cassava leaves in combination with either sera onggok or rice bran as compared to those receiving the other two rations. In conclusion it is obvious that cassava leaves in combination with either sera onggok or rice bran used as supplements could promote a better production in animal in the villages. (author). 7 refs, 1 fig, 5 tabs

  3. Effects of cassava diet on Cercopithecus aethiops livers: a case for cassava as the cause of both tropical splenomegaly syndrome (TSS) and endomyocardial fibrosis (EMF).

    Science.gov (United States)

    Sezi, C L

    1996-05-01

    The aetiology of endomyocardial fibrosis (EMF) and tropical splenomegaly syndrome (TSS) though speculative, was considered by the author to be the same or related since the two diseases may occur in the same individual and locality. Accordingly, when attempting to prove a hypothesis for the causation of EMF that prolonged ingestion of tuber (cassava/tapioca) associated with extreme deprivation of protein causes EMF; one group of three Cercopithecus aethiops was fed on uncooked cassava while a second group was fed with uncooked bananas and in addition to harvesting the hearts whenever the animal health deteriorated, livers were also harvested for histological changes. While hearts from the animals on cassava revealed changes seen in human EMF the livers from the same animals exhibited Kupffer cell hyperplasia and hypertrophy as well as sinusoidal lymphocytosis, features seen in human TSS thereby confirming that the aetiology of these two diseases is the same. However, the banana diet did not produce such changes.

  4. Cassava Breeding I: The Value of Breeding Value.

    Science.gov (United States)

    Ceballos, Hernán; Pérez, Juan C; Joaqui Barandica, Orlando; Lenis, Jorge I; Morante, Nelson; Calle, Fernando; Pino, Lizbeth; Hershey, Clair H

    2016-01-01

    Breeding cassava relies on several selection stages (single row trial-SRT; preliminary; advanced; and uniform yield trials-UYT). This study uses data from 14 years of evaluations. From more than 20,000 genotypes initially evaluated only 114 reached the last stage. The objective was to assess how the data at SRT could be used to predict the probabilities of genotypes reaching the UYT. Phenotypic data from each genotype at SRT was integrated into the selection index (SIN) used by the cassava breeding program. Average SIN from all the progenies derived from each progenitor was then obtained. Average SIN is an approximation of the breeding value of each progenitor. Data clearly suggested that some genotypes were better progenitors than others (e.g., high number of their progenies reaching the UYT), suggesting important variation in breeding values of progenitors. However, regression of average SIN of each parental genotype on the number of their respective progenies reaching UYT resulted in a negligible coefficient of determination (r (2) = 0.05). Breeding value (e.g., average SIN) at SRT was not efficient predicting which genotypes were more likely to reach the UYT stage. Number of families and progenies derived from a given progenitor were more efficient predicting the probabilities of the progeny from a given parent reaching the UYT stage. Large within-family genetic variation tends to mask the true breeding value of each progenitor. The use of partially inbred progenitors (e.g., S1 or S2 genotypes) would reduce the within-family genetic variation thus making the assessment of breeding value more accurate. Moreover, partial inbreeding of progenitors can improve the breeding value of the original (S0) parental material and sharply accelerate genetic gains. For instance, homozygous S1 genotypes for the dominant resistance to cassava mosaic disease (CMD) could be generated and selected. All gametes from these selected S1 genotypes would carry the desirable allele and

  5. CASSAVA BREEDING I: THE VALUE OF BREEDING VALUE

    Directory of Open Access Journals (Sweden)

    Hernán Ceballos

    2016-08-01

    Full Text Available Breeding cassava relies on several selection stages (single row trial-SRT; preliminary; advanced; and uniform yield trials - UYT. This study uses data from 14 years of evaluations. From more than 20,000 genotypes initially evaluated only 114 reached the last stage. The objective was to assess how the data at SRT could be used to predict the probabilities of genotypes reaching the UYT. Phenotypic data from each genotype at SRT was integrated into the selection index (SIN used by the cassava breeding program. Average SIN from all the progenies derived from each progenitor was then obtained. Average SIN is an approximation of the breeding value of each progenitor. Data clearly suggested that some genotypes were better progenitors than others (e.g. high number of their progenies reaching the UYT, suggesting important variation in breeding values of progenitors. However, regression of average SIN of each parental genotype on the number of their respective progenies reaching UYT resulted in a negligible coefficient of determination (r2 = 0.05. Breeding value (e.g. average SIN at SRT was not efficient predicting which genotypes were more likely to reach the UYT stage. Number of families and progenies derived from a given progenitor were more efficient predicting the probabilities of the progeny from a given parent reaching the UYT stage. Large within-family genetic variation tends to mask the true breeding value of each progenitor. The use of partially inbred progenitors (e.g. S1 or S2 genotypes would reduce the within-family genetic variation thus making the assessment of breeding value more accurate. Moreover, partial inbreeding of progenitors can improve the breeding value of the original (S0 parental material and sharply accelerate genetic gains. For instance, homozygous S1 genotypes for the dominant resistance to cassava mosaic disease could be generated and selected. All gametes from these selected S1 genotypes would carry the desirable allele

  6. Cassava Breeding I: The Value of Breeding Value

    Science.gov (United States)

    Ceballos, Hernán; Pérez, Juan C.; Joaqui Barandica, Orlando; Lenis, Jorge I.; Morante, Nelson; Calle, Fernando; Pino, Lizbeth; Hershey, Clair H.

    2016-01-01

    Breeding cassava relies on several selection stages (single row trial-SRT; preliminary; advanced; and uniform yield trials—UYT). This study uses data from 14 years of evaluations. From more than 20,000 genotypes initially evaluated only 114 reached the last stage. The objective was to assess how the data at SRT could be used to predict the probabilities of genotypes reaching the UYT. Phenotypic data from each genotype at SRT was integrated into the selection index (SIN) used by the cassava breeding program. Average SIN from all the progenies derived from each progenitor was then obtained. Average SIN is an approximation of the breeding value of each progenitor. Data clearly suggested that some genotypes were better progenitors than others (e.g., high number of their progenies reaching the UYT), suggesting important variation in breeding values of progenitors. However, regression of average SIN of each parental genotype on the number of their respective progenies reaching UYT resulted in a negligible coefficient of determination (r2 = 0.05). Breeding value (e.g., average SIN) at SRT was not efficient predicting which genotypes were more likely to reach the UYT stage. Number of families and progenies derived from a given progenitor were more efficient predicting the probabilities of the progeny from a given parent reaching the UYT stage. Large within-family genetic variation tends to mask the true breeding value of each progenitor. The use of partially inbred progenitors (e.g., S1 or S2 genotypes) would reduce the within-family genetic variation thus making the assessment of breeding value more accurate. Moreover, partial inbreeding of progenitors can improve the breeding value of the original (S0) parental material and sharply accelerate genetic gains. For instance, homozygous S1 genotypes for the dominant resistance to cassava mosaic disease (CMD) could be generated and selected. All gametes from these selected S1 genotypes would carry the desirable allele and

  7. 木薯种植机种茎切断装置的设计%Design of Cassava Stalk Cutter for Cassava Planting Machine

    Institute of Scientific and Technical Information of China (English)

    崔振德; 邓干然; 李国杰; 刘智强; 郑爽; 李玲

    2017-01-01

    机械化种植技术能够大大提高木薯种植效率,降低种植成本,是木薯田间生产大势所趋,而国内木薯种植设备研究起步晚,尚存在诸多问题。为此,结合木薯种植农艺要求及木薯种茎特性,针对木薯种植机种茎切断装置设计中存在的问题,进行了有关切秆装置设计的理论研究,分别对外形尺寸、整体结构、切秆刀辊、刀片及护盖等进行了分析与设计。试验表明:所设计的木薯种茎切断装置能够稳定切断木薯秆,拖拉机行驶速度约1.2m/s 时,作业稳定性高,无故障作业面积可达40hm2以上。%Mechanized planting techniques can greatly improve the efficiency of cassava planting, reduce the cost, it's development trend of cassava field production. However, domestic research on cassava planting machine is not enough, there are still many problems. Firstly, studied the problems of cassava stalk cutter occurred when planting machines had worked in fields. Then theoretical studies on designing of cassava stalk cutter was did. At last the overall structure of cut-ter, cutter roller, blade and cover were analyzed and designed respectively referencing agronomy planting requirements and cassava stalk biological and physical characteristics. Tests shows that this type cassava stalk cutting device worked stably. When a cassava planting machine with designed cutter driven by a tractor moving about 1. 2m/s, it has the best performance. It worked 600 acres with trouble-free operation.

  8. Instant blend from cassava derivatives produced by extrusion

    Directory of Open Access Journals (Sweden)

    Fernanda Rossi Moretti Trombini

    2016-03-01

    Full Text Available ABSTRACT: The current research aimed to evaluate the effects of extrusion parameters on the physical characteristics of extruded blends of cassava leaf flour and starch. A factorial central composite design with four independent variables and the response surface methodology were used to evaluate the results of color parameters (L*, a*, b*, water absorption index, water solubility index and paste properties, according to the variations in the leaf flour percentage (1.5 to 7.5%, extrusion temperature (60 to 100ºC, screw speed (175 to 231rpm and moisture (20 to 30%. Extrusion conditions affect color, water absorption and water solubility indexes and paste properties of blends. The intermediate tested conditions of variable parameters lead to obtain extruded products with higher cold viscosity and water absorption index and light color, desirable qualities for rapid preparation products.

  9. Study of the reproductive characteristics of nine cassava accessions

    International Nuclear Information System (INIS)

    Reproductive behaviour of two cultivars (AF and AN) and seven breeding lines (BA, AS, LA, BS-1, HO-008, ME and SE) of cassava (Manihot esculenta Crantz) was studied to obtain information pertaining to flowering habits and other reproductive characteristics of these potential parents required for future hybridization programmes. The accessions were grown on the Research Farm of the Biotechnology and Nuclear Agriculture Research Institute in the coastal savannah agro-ecological zone of Ghana between April 2008 and December 2009. For each accession, 40 stem cuttings, each bearing five to eight nodes, were prepared from the mid-section of healthy cassava stems and planted at a spacing of 1.5 m × 1.0 m while accessions were separated by a distance of 2 m. Ten plants were tagged per accession for the collection of data on key reproductive characteristics. All accessions flowered, suggesting that flower production may not be a limiting factor under the prevailing climatic conditions. Light microscopy revealed that one accession (BA) produced dysfunctional male flowers which were devoid of pollen. Mean days to flowering and fruiting varied significantly (P < 0.05) among the accessions, indicating the need to use different planting dates for different accessions to ensure synchronization of flowering. The accessions also differed significantly (P < 0.05) with respect to plant height at various levels of branching, as well as number of inflorescences, staminate and pistillate flowers, and fruit produced per branching level. There was also variation in percent seed set, embryo formation and fruit drop. The extensive variability observed among the accessions provides breeders with immense opportunities for carrying out cross combinations to generate new genotypes to meet specific objectives. (au)

  10. Response of cassava, maize and egusi melon in a three crop intercropping system at Makurdi, Nigeria

    Directory of Open Access Journals (Sweden)

    Michael Ojore Ijoyah

    2012-09-01

    Full Text Available Field experiments were conducted from April to December, during the 2010 and 2011 cropping seasons, at the Research Farm, University of Agriculture, Makurdi, Nigeria to evaluate the yield response of cassava, maize and egusi melon in a three crop intercropping system and to assess the advantage of the intercropping system. Sole cassava, sole maize, sole egusi melon and the intercrop of cassava, maize and egusi melon constituted the treatments. The four treatments were replicated four times in a randomized complete block design. The results obtained showed that in a cassava, maize and egusi melon mixture, intercropping did not significantly (P≤0.05 affect maize yield, however, intercrop yield of cassava was significantly (P≤0.05 depressed by 23.2 % and 31.0 % respectively, in 2010 and 2011, compared to that obtained from monocropped cassava. In addition, intercrop yield of egusi melon was significantly (P≤0.05 depressed by 34.8 % and 31.6 % respectively, in 2010 and 2011, compared to that produced from monocropped egusi melon. Total intercrop yield was greater than the component crop yields. Intercropping cassava, maize and egusi melon gave land equivalent ratio (LER values of 2.51 and 2.47 respectively, in years 2010 and 2011, indicating that higher productivity per unit area was achieved by growing the three crops together than by growing them separately. With these LER values, 60.2 % and 59.5 % of lands were saved respectively, in 2010 and 2011, which could be used for other agricultural purposes.

  11. Physiological Investigation and Transcriptome Analysis of Polyethylene Glycol (PEG)-Induced Dehydration Stress in Cassava.

    Science.gov (United States)

    Fu, Lili; Ding, Zehong; Han, Bingying; Hu, Wei; Li, Yajun; Zhang, Jiaming

    2016-01-01

    Cassava is an important tropical and sub-tropical root crop that is adapted to drought environment. However, severe drought stress significantly influences biomass accumulation and starchy root production. The mechanism underlying drought-tolerance remains obscure in cassava. In this study, changes of physiological characters and gene transcriptome profiles were investigated under dehydration stress simulated by polyethylene glycol (PEG) treatments. Five traits, including peroxidase (POD) activity, proline content, malondialdehyde (MDA), soluble sugar and soluble protein, were all dramatically induced in response to PEG treatment. RNA-seq analysis revealed a gradient decrease of differentially expressed (DE) gene number in tissues from bottom to top of a plant, suggesting that cassava root has a quicker response and more induced/depressed DE genes than leaves in response to drought. Overall, dynamic changes of gene expression profiles in cassava root and leaves were uncovered: genes related to glycolysis, abscisic acid and ethylene biosynthesis, lipid metabolism, protein degradation, and second metabolism of flavonoids were significantly induced, while genes associated with cell cycle/organization, cell wall synthesis and degradation, DNA synthesis and chromatin structure, protein synthesis, light reaction of photosynthesis, gibberelin pathways and abiotic stress were greatly depressed. Finally, novel pathways in ABA-dependent and ABA-independent regulatory networks underlying PEG-induced dehydration response in cassava were detected, and the RNA-Seq results of a subset of fifteen genes were confirmed by real-time PCR. The findings will improve our understanding of the mechanism related to dehydration stress-tolerance in cassava and will provide useful candidate genes for breeding of cassava varieties better adapted to drought environment.

  12. Two cassava promoters related to vascular expression and storage root formation.

    Science.gov (United States)

    Zhang, Peng; Bohl-Zenger, Susanne; Puonti-Kaerlas, Johanna; Potrykus, Ingo; Gruissem, Wilhelm

    2003-12-01

    Cassava ( Manihot esculenta Crantz) storage roots, organs accumulating large amounts of starch, develop from primary roots via secondary growth. The availability of promoters related to storage-root formation is a prerequisite for engineering root traits in cassava. Two cDNAs, c15 and c54, were identified from a storage-root cDNA library of cassava MCol1505 via differential screening. The transcripts of c15 and c54 were detected in storage roots but not in leaves by Northern analysis. Homology analysis of the deduced amino acid sequences showed that C15 is likely to be related to cytochrome P450 proteins, which are involved in the oxidative degradation of various compounds, while C54 may be related to Pt2L4, a cassava glutamic acid-rich protein. The promoter regions of c15 and c54 were isolated from the corresponding clones in a cassava genomic library. A 1,465-bp promoter fragment ( p15/1.5) of c15 and a 1,081-bp promoter region ( p54/1.0) of c54 were translationally fused to the uidA reporter gene, and introduced into cassava and Arabidopsis thaliana (L.) Heynh. The expression patterns of p15/1.5::uidA and p54/1.0::uidA in transgenic plants showed that both promoters are predominantly active in phloem, cambium and xylem vessels of vascular tissues from leaves, stems, and root systems. More importantly, strong beta-glucuronidase activity was also detected in the starch-rich parenchyma cells of transgenic storage roots. Our results demonstrate that the two promoters are related to vascular expression and secondary growth of storage roots in cassava.

  13. An EST-derived SNP and SSR genetic linkage map of cassava (Manihot esculenta Crantz).

    Science.gov (United States)

    Rabbi, Ismail Yusuf; Kulembeka, Heneriko Philbert; Masumba, Esther; Marri, Pradeep Reddy; Ferguson, Morag

    2012-07-01

    Cassava (Manihot esculenta Crantz) is one of the most important food security crops in the tropics and increasingly being adopted for agro-industrial processing. Genetic improvement of cassava can be enhanced through marker-assisted breeding. For this, appropriate genomic tools are required to dissect the genetic architecture of economically important traits. Here, a genome-wide SNP-based genetic map of cassava anchored in SSRs is presented. An outbreeder full-sib (F1) family was genotyped on two independent SNP assay platforms: an array of 1,536 SNPs on Illumina's GoldenGate platform was used to genotype a first batch of 60 F1. Of the 1,358 successfully converted SNPs, 600 which were polymorphic in at least one of the parents and was subsequently converted to KBiosciences' KASPar assay platform for genotyping 70 additional F1. High-precision genotyping of 163 informative SSRs using capillary electrophoresis was also carried out. Linkage analysis resulted in a final linkage map of 1,837 centi-Morgans (cM) containing 568 markers (434 SNPs and 134 SSRs) distributed across 19 linkage groups. The average distance between adjacent markers was 3.4 cM. About 94.2% of the mapped SNPs and SSRs have also been localized on scaffolds of version 4.1 assembly of the cassava draft genome sequence. This more saturated genetic linkage map of cassava that combines SSR and SNP markers should find several applications in the improvement of cassava including aligning scaffolds of the cassava genome sequence, genetic analyses of important agro-morphological traits, studying the linkage disequilibrium landscape and comparative genomics.

  14. Physiological Investigation and Transcriptome Analysis of Polyethylene Glycol (PEG)-Induced Dehydration Stress in Cassava.

    Science.gov (United States)

    Fu, Lili; Ding, Zehong; Han, Bingying; Hu, Wei; Li, Yajun; Zhang, Jiaming

    2016-01-01

    Cassava is an important tropical and sub-tropical root crop that is adapted to drought environment. However, severe drought stress significantly influences biomass accumulation and starchy root production. The mechanism underlying drought-tolerance remains obscure in cassava. In this study, changes of physiological characters and gene transcriptome profiles were investigated under dehydration stress simulated by polyethylene glycol (PEG) treatments. Five traits, including peroxidase (POD) activity, proline content, malondialdehyde (MDA), soluble sugar and soluble protein, were all dramatically induced in response to PEG treatment. RNA-seq analysis revealed a gradient decrease of differentially expressed (DE) gene number in tissues from bottom to top of a plant, suggesting that cassava root has a quicker response and more induced/depressed DE genes than leaves in response to drought. Overall, dynamic changes of gene expression profiles in cassava root and leaves were uncovered: genes related to glycolysis, abscisic acid and ethylene biosynthesis, lipid metabolism, protein degradation, and second metabolism of flavonoids were significantly induced, while genes associated with cell cycle/organization, cell wall synthesis and degradation, DNA synthesis and chromatin structure, protein synthesis, light reaction of photosynthesis, gibberelin pathways and abiotic stress were greatly depressed. Finally, novel pathways in ABA-dependent and ABA-independent regulatory networks underlying PEG-induced dehydration response in cassava were detected, and the RNA-Seq results of a subset of fifteen genes were confirmed by real-time PCR. The findings will improve our understanding of the mechanism related to dehydration stress-tolerance in cassava and will provide useful candidate genes for breeding of cassava varieties better adapted to drought environment. PMID:26927071

  15. Utilization of cassava leaf (Manihot esculenta, Crantz) in concentrate mixtures for swamp buffaloes in Thailand

    International Nuclear Information System (INIS)

    A study was made to evaluate dried cassava leaf (Manihot esculenta, Crantz) as a protein supplement in diets for buffaloes. Five swamp buffaloes aged 2.5 years (average liveweight 249 ± 6.1 kg) were randomly allotted to five concentrate mixture containing 0, 7.5, 15, 22.5 and 30g/kg dry matter (DM) dried cassava leaf containing 11.8-13.9% crude protein, 11.3-13.0 MJ metabolisable energy/kg DM, 9.7-18.4% neutral detergent fibre acid, 6.9-13.9% acid detergent fibre. The buffaloes were given urea-treated rice straw (UTS) ad libitum and one of the concentrate mixtures during each of five measurement periods according to a 5 x 5 Latin square design. Each period had a 21-d preliminary interval followed by a 7-d collection interval while the animals were in metabolic crates. Digestibilities of nutrients and N-balances were higher when cassava leaf was present in the concentrate mixtures, being highest for the 7.5% cassava leaf mixture. The ammonia and total VFA concentrations in rumen fluid and total volatile fatty acids (TVFA) and blood urea concentrations did not differ significantly between treatments. As the level of dried cassava leaf increased, the price of the mixtures decreased markedly. Dried cassava leaf therefore proved to be a good supplement for ruminants during seasonal dry periods when other feed supplies were not abundant. Incorporation of the dried cassava leaf in the concentrate up to 30% DM, and possible higher, could reduce the cost of diets for buffaloes relative to diets containing other protein sources such as soyabean meal. (author). 17 refs, 4 tabs

  16. Validation of Reference Genes for Relative Quantitative Gene Expression Studies in Cassava (Manihot esculenta Crantz) by Using Quantitative Real-Time PCR

    Science.gov (United States)

    Hu, Meizhen; Hu, Wenbin; Xia, Zhiqiang; Zhou, Xincheng; Wang, Wenquan

    2016-01-01

    Reverse transcription quantitative real-time polymerase chain reaction (real-time PCR, also referred to as quantitative RT-PCR or RT-qPCR) is a highly sensitive and high-throughput method used to study gene expression. Despite the numerous advantages of RT-qPCR, its accuracy is strongly influenced by the stability of internal reference genes used for normalizations. To date, few studies on the identification of reference genes have been performed on cassava (Manihot esculenta Crantz). Therefore, we selected 26 candidate reference genes mainly via the three following channels: reference genes used in previous studies on cassava, the orthologs of the most stable Arabidopsis genes, and the sequences obtained from 32 cassava transcriptome sequence data. Then, we employed ABI 7900 HT and SYBR Green PCR mix to assess the expression of these genes in 21 materials obtained from various cassava samples under different developmental and environmental conditions. The stability of gene expression was analyzed using two statistical algorithms, namely geNorm and NormFinder. geNorm software suggests the combination of cassava4.1_017977 and cassava4.1_006391 as sufficient reference genes for major cassava samples, the union of cassava4.1_014335 and cassava4.1_006884 as best choice for drought stressed samples, and the association of cassava4.1_012496 and cassava4.1_006391 as optimal choice for normally grown samples. NormFinder software recommends cassava4.1_006884 or cassava4.1_006776 as superior reference for qPCR analysis of different materials and organs of drought stressed or normally grown cassava, respectively. Results provide an important resource for cassava reference genes under specific conditions. The limitations of these findings were also discussed. Furthermore, we suggested some strategies that may be used to select candidate reference genes. PMID:27242878

  17. Validation of Reference Genes for Relative Quantitative Gene Expression Studies in Cassava (Manihot esculenta Crantz) by Using Quantitative Real-Time PCR.

    Science.gov (United States)

    Hu, Meizhen; Hu, Wenbin; Xia, Zhiqiang; Zhou, Xincheng; Wang, Wenquan

    2016-01-01

    Reverse transcription quantitative real-time polymerase chain reaction (real-time PCR, also referred to as quantitative RT-PCR or RT-qPCR) is a highly sensitive and high-throughput method used to study gene expression. Despite the numerous advantages of RT-qPCR, its accuracy is strongly influenced by the stability of internal reference genes used for normalizations. To date, few studies on the identification of reference genes have been performed on cassava (Manihot esculenta Crantz). Therefore, we selected 26 candidate reference genes mainly via the three following channels: reference genes used in previous studies on cassava, the orthologs of the most stable Arabidopsis genes, and the sequences obtained from 32 cassava transcriptome sequence data. Then, we employed ABI 7900 HT and SYBR Green PCR mix to assess the expression of these genes in 21 materials obtained from various cassava samples under different developmental and environmental conditions. The stability of gene expression was analyzed using two statistical algorithms, namely geNorm and NormFinder. geNorm software suggests the combination of cassava4.1_017977 and cassava4.1_006391 as sufficient reference genes for major cassava samples, the union of cassava4.1_014335 and cassava4.1_006884 as best choice for drought stressed samples, and the association of cassava4.1_012496 and cassava4.1_006391 as optimal choice for normally grown samples. NormFinder software recommends cassava4.1_006884 or cassava4.1_006776 as superior reference for qPCR analysis of different materials and organs of drought stressed or normally grown cassava, respectively. Results provide an important resource for cassava reference genes under specific conditions. The limitations of these findings were also discussed. Furthermore, we suggested some strategies that may be used to select candidate reference genes.

  18. Characterization of an 18,166 EST dataset for cassava (Manihot esculenta Crantz) enriched for drought-responsive genes

    Science.gov (United States)

    Cassava (Manihot esculenta Crantz) is a staple food for over 600 million people in the tropics and subtropics and is increasingly used as an industrial crop for starch production. Cassava has a high growth rate under optimal conditions but also performs well in drought-prone areas and on marginal so...

  19. Biofortified Cassava with Pro-Vitamin A is sensory and culturally acceptable for consumption by primary school children in Kenya

    NARCIS (Netherlands)

    Talsma, E.F.; Boonstra, A.; Kok, de B.P.H.; Mbera, G.N.K.; Mwangi, A.M.; Brouwer, I.D.

    2013-01-01

    Background: Biofortification of cassava with pro-vitamin A can potentially reduce vitamin A deficiency in low-income countries. However, little is known about consumer acceptance of this deep yellow variety of cassava compared to the commonly available white varieties. We aimed to determine the sens

  20. Cassava (Manihot esculenta) transcriptome analysis in response to infection by the fungus Colletotrichum gloeosporioides using an oligonucleotide-DNA microarray.

    Science.gov (United States)

    Utsumi, Yoshinori; Tanaka, Maho; Kurotani, Atsushi; Yoshida, Takuhiro; Mochida, Keiichi; Matsui, Akihiro; Ishitani, Manabu; Sraphet, Supajit; Whankaew, Sukhuman; Asvarak, Thipa; Narangajavana, Jarunya; Triwitayakorn, Kanokporn; Sakurai, Tetsuya; Seki, Motoaki

    2016-07-01

    Cassava anthracnose disease (CAD), caused by the fungus Colletotrichum gloeosporioides f. sp. Manihotis, is a serious disease of cassava (Manihot esculenta) worldwide. In this study, we established a cassava oligonucleotide-DNA microarray representing 59,079 probes corresponding to approximately 30,000 genes based on original expressed sequence tags and RNA-seq information from cassava, and applied it to investigate the molecular mechanisms of resistance to fungal infection using two cassava cultivars, Huay Bong 60 (HB60, resistant to CAD) and Hanatee (HN, sensitive to CAD). Based on quantitative real-time reverse transcription PCR and expression profiling by the microarray, we showed that the expressions of various plant defense-related genes, such as pathogenesis-related (PR) genes, cell wall-related genes, detoxification enzyme, genes related to the response to bacterium, mitogen-activated protein kinase (MAPK), genes related to salicylic acid, jasmonic acid and ethylene pathways were higher in HB60 compared with HN. Our results indicated that the induction of PR genes in HB60 by fungal infection and the higher expressions of defense response-related genes in HB60 compared with HN are likely responsible for the fungal resistance in HB60. We also showed that the use of our cassava oligo microarray could improve our understanding of cassava molecular mechanisms related to environmental responses and development, and advance the molecular breeding of useful cassava plants.

  1. Effects of processing, cooking, and storage on ß-carotene retention and bioaccessibility in biofortified cassava (Manihot esculenta)

    Science.gov (United States)

    Biofortification of cassava with beta-carotene is currently being tested in African populations where cassava is a staple food and vitamin A deficiency is a public health problem. Measuring the impact of traditional African processing and cooking on beta-carotene concentration and bioaccessibility ...

  2. Morphological and mechanical characterization of thermoplastic starch and its blends with polylactic acid using cassava starch and bagasse

    Science.gov (United States)

    This study aims the use of an agro waste coming from the industrialization of cassava starch, known as cassava bagasse (BG). This material contains residual starch and cellulose fibers which can be used to obtain thermoplastic starch (TPS) and /or blends reinforced with fibers. In this context, it w...

  3. Biofortified cassava increases ß-carotene and vitamin A concentrations in the TAG-rich plasma layer of American women

    Science.gov (United States)

    Background: Biofortification of cassava with the provitamin A (PVA) carotenoid beta-carotene (BC) is a potential mechanism for alleviating vitamin A (VA) deficiency. Cassava is a staple food in the African diet, but the human bioavailability of BC within this food is unknown. Objective: To evaluat...

  4. Cassava (Manihot esculenta) transcriptome analysis in response to infection by the fungus Colletotrichum gloeosporioides using an oligonucleotide-DNA microarray.

    Science.gov (United States)

    Utsumi, Yoshinori; Tanaka, Maho; Kurotani, Atsushi; Yoshida, Takuhiro; Mochida, Keiichi; Matsui, Akihiro; Ishitani, Manabu; Sraphet, Supajit; Whankaew, Sukhuman; Asvarak, Thipa; Narangajavana, Jarunya; Triwitayakorn, Kanokporn; Sakurai, Tetsuya; Seki, Motoaki

    2016-07-01

    Cassava anthracnose disease (CAD), caused by the fungus Colletotrichum gloeosporioides f. sp. Manihotis, is a serious disease of cassava (Manihot esculenta) worldwide. In this study, we established a cassava oligonucleotide-DNA microarray representing 59,079 probes corresponding to approximately 30,000 genes based on original expressed sequence tags and RNA-seq information from cassava, and applied it to investigate the molecular mechanisms of resistance to fungal infection using two cassava cultivars, Huay Bong 60 (HB60, resistant to CAD) and Hanatee (HN, sensitive to CAD). Based on quantitative real-time reverse transcription PCR and expression profiling by the microarray, we showed that the expressions of various plant defense-related genes, such as pathogenesis-related (PR) genes, cell wall-related genes, detoxification enzyme, genes related to the response to bacterium, mitogen-activated protein kinase (MAPK), genes related to salicylic acid, jasmonic acid and ethylene pathways were higher in HB60 compared with HN. Our results indicated that the induction of PR genes in HB60 by fungal infection and the higher expressions of defense response-related genes in HB60 compared with HN are likely responsible for the fungal resistance in HB60. We also showed that the use of our cassava oligo microarray could improve our understanding of cassava molecular mechanisms related to environmental responses and development, and advance the molecular breeding of useful cassava plants. PMID:27138000

  5. Cloning of a peroxidase gene from cassava with potential as a molecular marker for resistance to bacterial blight

    Directory of Open Access Journals (Sweden)

    Pereira Luiz Filipe

    2003-01-01

    Full Text Available Cassava bacterial blight (CBB, caused by Xanthomonas axonopodis pv. manihotis, is considered one of the most important bacterial diseases of cassava (Manihot esculenta Crantz. In order to characterize the cassava genes involved in resistance to this disease, a genomic clone of a cationic peroxidase gene, MEPX1, was isolated by PCR from cassava cultivar MCOL 22. The DNA sequence of MEPX1 showed high homology with other plant peroxidase genes and contained a large intron typical of peroxidase genes. The predicted translation product showed a heme-ligand motif, also a characteristic of peroxidases, as well as phosphorylation, myristoylation and glycosylation sites. The amino acid sequence had 75 % homology with two Arabidopsis thaliana peroxidases. A Southern blot of 17 cassava cultivars, probed with MEPX1, showed multiple hybridization bands. Polymorphisms between cultivars generally reflected geographic origin, but there was also an association with resistance to CBB, indicating that MEPX1 could be a potentially useful marker for this trait.

  6. Enhancing fermentable sugar yield from cassava pulp for bioethanol production: microwave-coupled enzymatic hydrolysis approach.

    Science.gov (United States)

    Sudha, A; Sivakumar, V; Sangeetha, V; Devi, K S Priyenka

    2015-08-01

    Cassava pulp, a potential biological feedstock for ethanol production has been subjected to microwave-assisted alkali pretreatment and microwave-coupled enzymatic hydrolysis. Microwave pretreatment may be a good alternative as it can reduce the pretreatment time and improve the enzymatic activity during hydrolysis. Liquid to solid ratio for the pretreatment of cassava pulp was found to be 20:1. Cassava pulp was pretreated at various NaOH concentration, microwave temperature and gave maximum yield of reducing sugar with 1.5% NaOH at 90 °C in 30 min than conventional alkali pretreatment after enzymatic hydrolysis. The subsequent enzymatic saccharification of pretreated cassava pulp using α amylase dosage of 400 IU at microwave temperature of 90 °C resulted in highest reducing sugar yield of 723 mg/g pulp. Microwave-assisted alkali pretreatment improved the enzymatic saccharification of cassava pulp by increasing its accessibility to hydrolytic enzymes. Microwave-assisted alkali pretreatment and microwave-coupled enzymatic hydrolysis are found to be efficient for improving the yield of reducing sugar. PMID:25832789

  7. Design, Construction and Performance Evaluation of a Modified Cassava Milling Machine

    Directory of Open Access Journals (Sweden)

    K.N. Nwaigwe

    2012-09-01

    Full Text Available This study on the design and construction of a modified cassava milling machine was done, owing to the inability of existing mills to meet the demand of cassava flour in bakery industries. Rational design by drawing and calculations and fabrication in the Centre for Industrial Studies (CIS FUTO were used to bring this mill to reality. The modified cassava milling machine has a milling efficiency of 82.3%, it is dust free and self-cleaning and due to proper air circulation does not destroy the cassava flour produced by overheating. The cassava flour produced was found to have a fineness modulus (fm of 0.31, Uniformity index (U of 0: 1: 9 (coarse: medium: fine and effective size (D10 of 0.075 mm which is better than that produced by an existing mill (hammer mill of fineness modulus (fm 2.32, uniformity index (U of 4:1:5 and effective size (D10 of 0.085 mm.

  8. Chemical Attributes of Soil Fertilized with Cassava Mill Wastewater and Cultivated with Sunflower

    Directory of Open Access Journals (Sweden)

    Mara Suyane Marques Dantas

    2014-01-01

    Full Text Available The use of waste arising from agroindustrial activities, such as cassava wastewater, has been steadily implemented in order to reduce environmental pollution and nutrient utilization. The aim of this study is that the changes in chemical properties of dystrophic red-yellow latosol (oxisol were evaluated at different sampling times after reuse of cassava wastewater as an alternative to mineral fertilizer in the cultivation of sunflower, hybrid Helio 250. The experiment was conducted at the Experimental Station of the Agricultural Research Company of Pernambuco (IPA, located in Vitória de Santo Antão. The experimental design was randomized blocks with 6×5 subplots; six doses of cassava wastewater (0; 8.5; 17.0; 34.0; 68.0; and 136 m3 ha−1; and five sampling times (21, 42, 63, 84, and 105 days after applying the cassava wastewater, with four replications. Concentrations of available phosphorus and exchangeable potassium, calcium, magnesium and sodium, pH, and electrical conductivity of the soil saturation extract were evaluated. Results indicate that cassava wastewater is an efficient provider of nutrients to the soil and thus to the plants, making it an alternative to mineral fertilizers.

  9. Rheological behavior of gamma-irradiated cassava (Manihot esculenta crantz) starch

    International Nuclear Information System (INIS)

    Cassava starch is the by-product of the process of pressing water out of cassava to make cassava meal. The juice has a fine starch, similar to rice or potato starch that, when dried, yields polvilho doce (sweet manioc starch); from the fermented juice comes polvilho azedo (sour manioc starch). Cassava starch can perform most of the functions where maize, rice and wheat starch are currently used. The aim of the present work was to determine the influence or ionizing radiation on the rheological behavior of aqueous preparations of gamma-irradiated cassava starch at different concentrations. Samples of polvilho doce and polvilho azedo were obtained at the local market and irradiated in plastic bags in a Gammacell 220 with doses of 1, 3 e 5 kGy, dose rate ∼ 1.2 kGy h-1. A Brooksfield viscometer was employed for the viscosity measurements. The results showed a strong dependence of the viscosity with the concentration of the starch solutions. In most of the cases there was a decrease of viscosity with the increase of the radiation dose usually seen in irradiated polysaccharides. Nevertheless, the dose response relation of the two kind of starch was different. (author)

  10. Intake, digestibility and performance of lambs fed with diets containing cassava peels

    Directory of Open Access Journals (Sweden)

    Gilmara Santos Guimarães

    2014-06-01

    Full Text Available Sheep farming is designated to economic exploitation, and dry matter intake is the most important factor that influences the performance of animal, thus seeking alternative foods. This study aimed to evaluate the effects of inclusion levels of cassava peel on intake, digestibility and performance of feedlot lambs. We used 32 crossbred lambs Santa Inês uncastrated, mean body weight of 21 ± 1.5 kg. Treatments were arranged in a randomized design to animals, with inclusion levels of cassava peel (0, 10, 20, 30% in the diet dry matter and forage cassava leaf hay. During 70 days, there have been weighing the food provided, leftovers, and animals, and feces collection. The intake of dry matter (DMI, organic matter (OMI, crude protein (CPI, ether extract (EEI, neutral detergent fiber corrected for ash and protein (NDIap, total carbohydrates (CTI, non-fiber carbohydrates (NFCI, total digestible nutrients (TDNI, as well as DMI and NDFap/kgCP, DMI and NDFIap/PC0.75 levels have not been affected by the inclusion of cassava peel. Similar results for DM digestibility, NDF, CP, MO, CT and the TDN. DEE had a growing linear effect whereas DNFC presented a quadratic effect. Average daily gain (ADG, feed conversion (FC, initial body weight (BWinitial, final body weight (BWfinal, warm carcass weight (WCW and warm carcass yield (WCR showed no changes. It is concluded that the peel cassava may be included in diet until 30%, without change dry matter intake and animal performance.

  11. Nuclear and related techniques in the improvement of traditional fermentation processing of cassava

    International Nuclear Information System (INIS)

    Cassava, a starchy, cyanide-containing tuber root grown throughout the tropical areas, is one of the world's important food staples. The cassava root is very low in protein: its typical content for many cultivars is around one or two percent and thus is completely unable to provide the consumer with sufficient protein. The main goal of the Agency's Co-ordinated Research Programme (CRP) on ''Nuclear Techniques in the Improvement of Traditional Fermentation Practice in Developing Countries with Particular Emphasis on Cassava'' was to assist researchers from the tropical countries in the development of the techniques utilizing ionizing radiation for producing genetically improved mutants of the cassava-fermenting microorganisms with high abilities to eliminate poisonous glucosides and to increase the yield of desired nutrients to the fermented end-product. This document consists of fourteen final reports submitted by the scientists concerned to the final RCM as well as discussion materials covering main approaches to the problem of the improvement of traditional reprocessing of cassava, such as general microbiological aspects of the fermentation process and the genetic improvement of the selected specific microorganisms with the help of classical microbial mutagenesis methods and modern molecular gene-engineering techniques and tools. Refs, figs and tabs

  12. Comparative Economic Study of Mixed and Sole Cassava Cropping Systems in Nigeria

    Directory of Open Access Journals (Sweden)

    J. O. Ajayi

    2014-12-01

    Full Text Available Agricultural economists continue to argue if mixed or sole cassava cropping system is more economically profitable and in terms of yield and returns to farmers particularly for Nigeria which is the world’s largest producer of the crop. The study was carried out to analyse the economics comparatively of mixed and sole cassava cropping systems in Nigeria. The study made use of both primary and secondary data. Primary data were collected with the aid of well-structured questionnaires assisted with interview schedules. Field data collection was conducted between March and April, 2014. Multi-stage sampling technique was used to select four hundred and eighty (480 respondents across the six major cassava-producing states in Nigeria (Benue, Cross Rivers, Enugu, Kogi, Ondo, and Oyo. Data collected were analysed using descriptive statistics and comparative budgetary analysis. The study showed that mixed cropping system is more male-dominated than sole cropping system. The study also revealed that sole cassava cropping system is more economically profitable than mixed cassava cropping system while the later provides opportunities of all-year-round farm incomes to serve as a better poverty- alleviating mechanism.

  13. Carcass and non-carcass characteristics of sheep fed on cassava (Manihot pseudoglaziovii Pax & K. Hoffm.

    Directory of Open Access Journals (Sweden)

    Michel V Maciel

    2015-09-01

    Full Text Available Sheep production systems installed in the semi-arid region of Brazil depend on the forage support the 'caatinga' biome. This study aimed at evaluating the substitution of hybrid 'Tifton 85' (Cynodon spp. by cassava (Manihotpseudoglaziovii Pax & K. Hoffm. hay or silage on the components of sheep's' body weight. Twenty-four animals, with no defined breed, were used for the study, with an initial body weight of 19.77 ± 1.95 kg and an average age of 6-mo, being divided into three treatments ('Tifton 85' hay, cassava silage, and cassava hay. The animals were slaughtered at 56 d and all the body parts of the animals were weighed. Data were subjected to ANOVA and mean comparison test (P = 0.05. Means were superior (P 0.05 for body weight at slaughter and cold carcass weight, which had means of 28.10 and 12.38 kg, respectively. The hot carcass and leg yields showed values of 58% and 34%, respectively, and were not influenced (P > 0.05 by different forages. The constituents that were not components of the carcass, organs, offal, and by-products were not affected by the replacement of 'Tifton 85' hay by cassava hay or silage. Cassava hay or silage can replace 'Tifton 85' hay for feeding sheep in complete diets without compromising their body components' yields and weights.

  14. Study of the effects of hydrogen cyanide exposure in Cassava workers

    Directory of Open Access Journals (Sweden)

    Priya Kali Dhas

    2011-01-01

    Full Text Available Background : Hydrogen cyanide is the chemical responsible for tissue hypoxia. Chronic exposure to HCN may cause neurological, respiratory, cardiovascular and thyroid defects. Onset of symptoms depends on dose and duration of exposure. Large scale of Cassava processing could be disastrous due to discharge of hydrocyanic acid into the air. Cassava processing is the major industrial work in and around Salem. Hence the present study is taken to assess the effects of HCN exposure in Cassava workers. Materials and Methods: Thirty-nine workers from a Cassava processing unit at Salem and age-matched controls of the same economic status were taken up for this study. Clinical history was obtained with a questionnaire and their Blood sugar, lipid profile, serum total protein, urea, creatinine, AST, ALT and T 3 , T 4 , TSH were estimated using a fasting blood sample and AIP was calculated. Statistical analysis was done by student t test. Results: Our study reveals a significant increase in triglyceride in Cassava workers when compared to the control. Atherogenic index of plasma (AIP is statistically highly significant. A significant decrease was seen in T 4. Conclusion: An increase in TGL and AIP shows a higher degree of cardiovascular risk. A decrease in T4 suggests an insufficient iodine uptake by thyroid gland. Hence a periodic medical evaluation should be done on such workers for their safety and to prevent the health hazard.

  15. Konzo and dietary pattern in cassava-consuming populations of Popokabaka, Democratic Republic of Congo.

    Science.gov (United States)

    Diasolua Ngudi, D; Banea-Mayambu, J-P; Lambein, F; Kolsteren, P

    2011-03-01

    Food frequencies and 24h diet recall were registered from 487 randomly selected heads of household in Popokabaka (Bandundu Province, DRC) where the first cases of konzo were reported more than seventy years ago. Konzo is still occurring in this area with a prevalence of 1.4%. High prevalence of konzo was found to be associated with female gender (P = 0.0024), unmarried status (P = 0.030), illiteracy (P = 0.021), farmer as main occupation (P cassava from own farm land (P = 0.045). The diet was largely dominated by cassava. Luku, cassava flour stiff porridge, was consumed at least once during the day in 99.2% of households. A median of 304 g (max. 592 g; min. 120 g) of cassava flour providing 1070 kcal (max. 2085 kcal; min. 422 kcal)/day/person was used to prepare luku. Saka-saka (pounded cassava leaves) (40%), cowpeas (30%), sesame (23.2%), mbondi (Salacia pynaertii) (18.1%), mushrooms (17.7%) and mfumbwa (Gnetum africanum) (11.3%) were consumed as side-dishes with luku. These results showed that major foods consumed are of poor quality in protein, especially in sulphur containing amino acids.

  16. RNAi-derived field resistance to Cassava brown streak disease persists across the vegetative cropping cycle.

    Science.gov (United States)

    Odipio, John; Ogwok, Emmanuel; Taylor, Nigel J; Halsey, Mark; Bua, Anton; Fauquet, Claude M; Alicai, Titus

    2014-01-01

    A confined field trial was established to determine durability of RNAi-mediated resistance to Cassava brown streak disease (CBSD). Stem cuttings were obtained from field-grown cassava plants of cv 60444 transgenic for construct p718, consisting of an 894 bp inverted repeat sequence from the Ugandan Cassava brown streak virus (UCBSV) coat protein. Plants were established from three transgenic lines previously shown to provide complete resistance to UCBSV and differing levels of protection to the non-homologous virus species Cassava brown streak virus (CBSV), and grown for 11 months. CBSD symptoms were observed on shoots and storage roots of all non-transgenic cv 60444 control plants and transgenic lines p718-002 and p718-005, but not on p718-001. RT-PCR diagnostic showed tissues of plant lines p718-002 and p718-005 to be infected with CBSV, but free of UCBSV. All leaves and roots of p718-001 plants were to carry no detectable levels of either pathogen. Plants of cv 60444 in this field trial showed severe cassava mosaic disease symptoms, indicating that presence of replicating geminiviruses did not cause significant suppression of RNAi-mediated resistance to CBSD. Resistance to CBSD across a vegetative cropping cycle confirms earlier field data, and provides an important step in proof of concept for application of RNAi technology to control of CBSD under conditions encountered in farmers' fields.

  17. Strategies for elimination of cyanogens from cassava for reducing toxicity and improving food safety.

    Science.gov (United States)

    Nambisan, Bala

    2011-03-01

    Toxicity of cassava arises due to the presence of the cyanoglucosides linamarin and lotaustralin which are hydrolysed by endogenous enzyme linamarase to acetonecyanohydrin (ACN) and cyanide (CN) which are toxic. Major research efforts to eliminate/reduce cyanoglucosides have focused on (i) development of acyanogenic cassava varieties by breeding; (ii) controlling its metabolism; and (iii) processing to remove cyanogens. The cyanoglucoside (CNG) content in cassava is genetically controlled and cultivars may be classified as low (100 μg CN eq./g) varieties. Molecular techniques for reducing tuber CNG have focused on development of transgenic plants with reduced expression of cyt P 450 in leaves, or increased expression of hydroxynitrilelyase in tuber. For immediate solution, CNG content can be reduced using several processing methods. Traditional methods used for processing include boiling, drying, parboiling and drying, baking, steaming, frying and preparation of flour. These processes result in CN losses ranging from 25% to 98%. The cyanogen level in the final product is influenced both by the tuber CNG and the method of processing. In order to achieve safe levels of 10 μg/g in cassava products, new methods of processing, especially for cassava containing more than 250 μg CN eq./g, remains a challenging problem.

  18. The predatory mite Typhlodromalus aripo prefers green-mite induced plant odours from pubescent cassava varieties.

    Science.gov (United States)

    Onzo, Alexis; Hanna, Rachid; Sabelis, Maurice W

    2012-12-01

    It is well known that plant-inhabiting predators use herbivore-induced plant volatiles to locate herbivores being their prey. Much less known, however, is the phenomenon that genotypes of the same host plant species vary in the attractiveness of these induced chemical signals, whereas they also differ in characteristics that affect the predator's foraging success, such as leaf pubescence. In a series of two-choice experiments (using a Y-tube olfactometer) we determined the preference of Typhlodromalus aripo for pubescent versus glabrous cassava cultivars infested with the cassava green mite Mononychellus tanajoa and also the preference for cultivars within each of the two groups. We found that when offered a choice between pubescent and glabrous cassava cultivars (either apex or leaves), T. aripo was significantly more attracted to pubescent cultivars. For each cultivar, M. tanajoa infested leaves and apices were equally attractive to T. aripo. There was however some variation in the response of T. aripo to M. tanajoa-infested plant parts within the group of pubescent cultivars, as well as within the group of glabrous cultivars. Our study confirms not only that T. aripo uses herbivore-induced plant volatiles to search for prey in cassava fields, but it also shows that it can discriminate between glabrous and pubescent cultivars and prefers the latter. This knowledge can be useful in selecting cultivars that are attractive and suitable to T. aripo, which, in turn, may promote biological control of the cassava green mite.

  19. Cassava cyanogens and free amino acids in raw and cooked leaves.

    Science.gov (United States)

    Ngudi, D Diasolua; Kuo, Y-H; Lambein, F

    2003-08-01

    Cassava leaves (Manihot esculenta Crantz) constitute the main daily source of protein as supplement to the major staple food, the processed cassava roots in remote rural areas of Africa. Konzo, an upper motoneurone disease with permanent spastic paralysis of both legs, has been reported among populations consuming this unbalanced diet. In commercial pounded cassava leaves residual cyanogens and the presence of inherent potentially toxic non-protein amino acids were analysed to check their safety. The initial total cyanogens before cooking ranged from 35.9+/-0.4 to 107.5+/-0.8 mg HCN (hydrogen cyanide) equivalent kg(-1) dry weight. After cooking, the residual cyanogens were significantly reduced (Pcassava leaves. The non-protein amino acids gamma-amino butyric acid (GABA) and alpha-amino butyric acid (alpha-ABA) were detected. No known potentially toxic non-protein amino acid was found. In konzo-affected areas, cassava leaves with inadequate preparation and cooking can be a non-negligible source of dietary exposure to cyanogens apart from the cassava roots that are suggested to be involved in the aetiology of konzo.

  20. Rheological behavior of gamma-irradiated cassava (Manihot esculenta crantz) starch

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Orelio L.; Uehara, Vanessa B.; Mastro, Nelida L. del, E-mail: nlmastro@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    Cassava starch is the by-product of the process of pressing water out of cassava to make cassava meal. The juice has a fine starch, similar to rice or potato starch that, when dried, yields polvilho doce (sweet manioc starch); from the fermented juice comes polvilho azedo (sour manioc starch). Cassava starch can perform most of the functions where maize, rice and wheat starch are currently used. The aim of the present work was to determine the influence or ionizing radiation on the rheological behavior of aqueous preparations of gamma-irradiated cassava starch at different concentrations. Samples of polvilho doce and polvilho azedo were obtained at the local market and irradiated in plastic bags in a Gammacell 220 with doses of 1, 3 e 5 kGy, dose rate ∼ 1.2 kGy h-1. A Brooksfield viscometer was employed for the viscosity measurements. The results showed a strong dependence of the viscosity with the concentration of the starch solutions. In most of the cases there was a decrease of viscosity with the increase of the radiation dose usually seen in irradiated polysaccharides. Nevertheless, the dose response relation of the two kind of starch was different. (author)

  1. Cloning and characterization of a tuberous root-specific promoter from cassava (Manihot esculenta Crantz).

    Science.gov (United States)

    Koehorst-van Putten, Herma J J; Wolters, Anne-Marie A; Pereira-Bertram, Isolde M; van den Berg, Hans H J; van der Krol, Alexander R; Visser, Richard G F

    2012-12-01

    In order to obtain a tuberous root-specific promoter to be used in the transformation of cassava, a 1,728 bp sequence containing the cassava granule-bound starch synthase (GBSSI) promoter was isolated. The sequence proved to contain light- and sugar-responsive cis elements. Part of this sequence (1,167 bp) was cloned into binary vectors to drive expression of the firefly luciferase gene. Cassava cultivar Adira 4 was transformed with this construct or a control construct in which the luciferase gene was cloned behind the 35S promoter. Luciferase activity was measured in leaves, stems, roots and tuberous roots. As expected, the 35S promoter induced luciferase activity in all organs at similar levels, whereas the GBSSI promoter showed very low expression in leaves, stems and roots, but very high expression in tuberous roots. These results show that the cassava GBSSI promoter is an excellent candidate to achieve tuberous root-specific expression in cassava.

  2. Genetic fidelity and variability of micropropagated cassava plants (Manihot esculenta Crantz) evaluated using ISSR markers.

    Science.gov (United States)

    Vidal, Á M; Vieira, L J; Ferreira, C F; Souza, F V D; Souza, A S; Ledo, C A S

    2015-07-14

    Molecular markers are efficient for assessing the genetic fidelity of various species of plants after in vitro culture. In this study, we evaluated the genetic fidelity and variability of micropropagated cassava plants (Manihot esculenta Crantz) using inter-simple sequence repeat markers. Twenty-two cassava accessions from the Embrapa Cassava & Fruits Germplasm Bank were used. For each accession, DNA was extracted from a plant maintained in the field and from 3 plants grown in vitro. For DNA amplification, 27 inter-simple sequence repeat primers were used, of which 24 generated 175 bands; 100 of those bands were polymorphic and were used to study genetic variability among accessions of cassava plants maintained in the field. Based on the genetic distance matrix calculated using the arithmetic complement of the Jaccard's index, genotypes were clustered using the unweighted pair group method using arithmetic averages. The number of bands per primer was 2-13, with an average of 7.3. For most micropropagated accessions, the fidelity study showed no genetic variation between plants of the same accessions maintained in the field and those maintained in vitro, confirming the high genetic fidelity of the micropropagated plants. However, genetic variability was observed among different accessions grown in the field, and clustering based on the dissimilarity matrix revealed 7 groups. Inter-simple sequence repeat markers were efficient for detecting the genetic homogeneity of cassava plants derived from meristem culture, demonstrating the reliability of this propagation system.

  3. Determinants of economically optimal cassava-to-ethanol plant capacities with consideration of GHG emissions

    International Nuclear Information System (INIS)

    The successful realization of biofuel plants depends on a number of economic and ecological factors. In this work, the production of bioethanol from cassava in China's Guangxi province is investigated by combining an economic optimization approach with results from corresponding Life Cycle Assessments. By using the potential plant's capacity as the optimization variable, it becomes possible to show the trade-offs associated with different capacities, especially with regard to the achievable profitability and the corresponding greenhouse gas emissions. In contrast to distinct case studies, this approach aims for the identification of optimal capacities from a continuous range of potential capacities. The combined assessment is then applied to a Chinese scenario to determine the effects of factors such as fertilizer application and of the conversion of fresh cassava to cassava chips to identify favorable options for potential future cassava-to-ethanol plants. In general, such modeling approaches are expected to facilitate the bioenergy plant planning by approximating the economic and ecological consequences of plants of different capacities. - Highlights: • A Life Cycle Assessment of a cassava-to-ethanol plant in China is performed. • Optimization methods are used to enhance the understanding of biomass logistics. • The two methods are combined to investigate trade-offs between economy and ecology. • Transportation-related specific GHG emissions are constant for optimal capacities. • Ethanol/product price and conversion ratio are among the most important parameters

  4. Water use impact of ethanol at a gasoline substitution ratio of 5% from cassava in Nigeria

    Energy Technology Data Exchange (ETDEWEB)

    Adeoti, O. [Dept. of Agricultural Engineering, The Federal Polytechnic, Along Ikare Road, Ado Ekiti, Ekiti State (Nigeria)

    2010-07-15

    The process of fuel ethanol production from cassava root is connected to a chain of impacts on the water resource of the country where the cassava plant is grown and the root processed into fuel ethanol. The paper assesses the impact of the domestic production of 5 per cent ethanol (E5) needed under the Nigerian biofuel programme from cassava root on the water resource of Nigeria. Using the 2007 Premium Motor Spirit (PMS) consumption as the baseline, Nigeria will require about 0.49 hm{sup 3} of ethanol to blend 9.32 hm{sup 3} of PMS to arrive at the 2007 consumption estimates. The impact of the domestic production of this ethanol requirement translates to about 6.0 km{sup 3} of water; out of which about 48 per cent is green and about 52 per cent is blue. Addressing future impact typical of a developing economy like Nigeria, a three-scenario analysis was adopted to examine the impact of future growth in cassava-fuel ethanol requirement on the water resource of Nigeria, and also, the impact of improved water use on the future water footprint of E5. The projected water impact of cassava-ethanol production into the future ranges from 6.02 to 7.28 km{sup 3}, while improved water use could lower these values by about 0.04-2.35 km{sup 3} for the same period, 2010 to 2020, under the projection assumptions made. (author)

  5. Strategy of gene silencing in cassava for validation of resistance genes

    International Nuclear Information System (INIS)

    Cassava (Manihot esculenta) is a major source of food for more than 1000 million people in the world and constitutes an important staple crop. Cassava bacterial blight, caused by the gram negative bacterium Xanthomonas axonopodis pv. manihotis, is one of the most important constraints for this crop. A candidate resistance gene against cassava bacterial blight, named RXam1, has been identified previously. In this work, we employed the gene silencing approach using the African cassava mosaic virus (ACMV) to validate the function of the RXam1 gene. We used as positive control the su gen, which produce photo blanching in leaves when is silenced. Plants from the SG10735 variety were bombardment with the ACMV-A-SU+ACMV-B y ACMV-A-RXam1+ACMV-B constructions. The silencing efficiency employing the su gene was low, only one of seven plants showed photo blanching. In the putative silenced plants for the RXam1 gene, no presence of siRNAs corresponding to RXam1 was observed; although a low diminution of the RXam1 gene expression was obtained. The growth curves for the Xam strain CIO136 in cassava plants inoculated showing a little but no significance difference in the susceptibility in the silenced plants compared to not silenced

  6. DEVELOPMENT OF ADHESIVE TO THE BASIS OF CORN AND CASSAVA STARCH

    Directory of Open Access Journals (Sweden)

    Rosane Furtado Fabrício

    2014-05-01

    Full Text Available Corn and native cassava starch were modified by oxidation and acid hydrolysis, aiming to develop paper and paperboard stickers. The oxidation was made with Sodium hypochlorite (NaOCl in two distinct concentrations of active chloride which is present on oxidizing agent solution. The synthesis resulting products were used to make stickers and they were compared to corn and cassava starch based stickers without any modification, as well as commercial stickers based on polyvinyl acetate (PVA. Two different methodologies were tested using acid hydrolysis to modify corn and cassava starch, both using phosphoric acid (H3PO4 in order to obtain dextrin and subsequently use it in the production of stickers and also comparing them to petrochemical-based commercial stickers. Considering the different starch modifications methods (oxidation and acid hydrolysis, stickers based on renewable raw material were obtained, which combine biodegradability, low costs and availability.

  7. Post-harvest conservation of organic strawberries coated with cassava starch and chitosan

    Directory of Open Access Journals (Sweden)

    Raquel P Campos

    2011-10-01

    Full Text Available The strawberry is as non-climacteric fruit, but has a high post-harvest respiration rate, which leads to a rapid deterioration at room temperature. This study aimed to evaluate the application of biodegradable coating on postharvest conservation of organic strawberries, cv. Camarosa, packed in plastic hinged boxes and stored at 10ºC. The treatments consisted of: a control; b 2% cassava starch; c 1% chitosan; and d 2% cassava starch + 1% chitosan. Physical and chemical characteristics of fruits were evaluated at 3, 6 and 9 days of storage, and microbiological and sensory analyses were carried out at the end of the storage period. The treatments influenced positively the post-harvest quality of organic strawberries. The coating cassava starch + chitosan provided the best results, with less than 6% of loss in fruit mass, lower counts of yeast and psychrophilic microorganisms and the best appearance according to the sensory analysis.

  8. Toward better understanding of postharvest deterioration: biochemical changes in stored cassava (Manihot esculenta Crantz) roots.

    Science.gov (United States)

    Uarrota, Virgílio Gavicho; Nunes, Eduardo da Costa; Peruch, Luiz Augusto Martins; Neubert, Enilto de Oliveira; Coelho, Bianca; Moresco, Rodolfo; Domínguez, Moralba Garcia; Sánchez, Teresa; Meléndez, Jorge Luis Luna; Dufour, Dominique; Ceballos, Hernan; Becerra Lopez-Lavalle, Luis Augusto; Hershey, Clair; Rocha, Miguel; Maraschin, Marcelo

    2016-05-01

    Food losses can occur during production, postharvest, and processing stages in the supply chain. With the onset of worldwide food shortages, interest in reducing postharvest losses in cassava has been increasing. In this research, the main goal was to evaluate biochemical changes and identify the metabolites involved in the deterioration of cassava roots. We found that high levels of ascorbic acid (AsA), polyphenol oxidase (PPO), dry matter, and proteins are correlated with overall lower rates of deterioration. On the other hand, soluble sugars such as glucose and fructose, as well as organic acids, mainly, succinic acid, seem to be upregulated during storage and may play a role in the deterioration of cassava roots. Cultivar Branco (BRA) was most resilient to postharvest physiological deterioration (PPD), while Oriental (ORI) was the most susceptible. Our findings suggest that PPO, AsA, and proteins may play a distinct role in PPD delay. PMID:27247771

  9. Optimization of cassava root sieviate medium to an enriched animal feed by Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Mbah G.O

    2016-07-01

    Full Text Available - Optimization of the media components cassava root sieviate with Aspergellus Niger was carried out using Face-Centered Central Composite Design (FCCCD of the Response Surface Methodology (RSM and the responses were measured in terms of protein and crude fiber contents. Statistical Analysis (ANOVA of the result showed that time and substrate concentration had effect on biodegraded cassava root sieviate (p-value was 0.00 ie. 0.00 < 0.05. The optimum value of enriched cassava root sieviate with Aspergellus Niger were found to be on 10 days (time and 6g/10ml concentration resulting to 9.42% from 1.85% enrichment in protein content and degrading crude fiber to 8.38%, from 70.3%, thus indicating the potency of Aspergillus niger for the production of economical livestock feed from renewable source.

  10. Bio-ethanol production from non-food parts of cassava (Manihot esculenta Crantz).

    Science.gov (United States)

    Nuwamanya, Ephraim; Chiwona-Karltun, Linley; Kawuki, Robert S; Baguma, Yona

    2012-05-01

    Global climate issues and a looming energy crisis put agriculture under pressure in Sub-Saharan Africa. Climate adaptation measures must entail sustainable development benefits, and growing crops for food as well as energy may be a solution, removing people from hunger and poverty without compromising the environment. The present study investigated the feasibility of using non-food parts of cassava for energy production and the promising results revealed that at least 28% of peels and stems comprise dry matter, and 10 g feedstock yields >8.5 g sugar, which in turn produced >60% ethanol, with pH ≈ 2.85, 74-84% light transmittance and a conductivity of 368 mV, indicating a potential use of cassava feedstock for ethanol production. Thus, harnessing cassava for food as well as ethanol production is deemed feasible. Such a system would, however, require supportive policies to acquire a balance between food security and fuel.

  11. Bio-ethanol production from non-food parts of Cassava (Manihot esculenta Crantz)

    Energy Technology Data Exchange (ETDEWEB)

    Nuwamanya, Ephraim; Kawuki, Robert S.; Baguma, Yona [National Agricultural Research organization, National Crops Resources Research Inst. (NaCRRI), Kampala (Uganda); Chiwona-Karltun, Linley [Dept. of Urban and Rural Development, Swedish Univ. of Agricultural Sciences, Uppsala (Sweden)], email: Linley.karltun@slu.se

    2012-03-15

    Global climate issues and a looming energy crisis put agriculture under pressure in Sub-Saharan Africa. Climate adaptation measures must entail sustainable development benefits, and growing crops for food as well as energy may be a solution, removing people from hunger and poverty without compromising the environment. The present study investigated the feasibility of using non-food parts of cassava for energy production and the promising results revealed that at least 28% of peels and stems comprise dry matter, and 10 g feedstock yields >8.5 g sugar, which in turn produced >60% ethanol, with pH {approx} 2.85, 74-84% light transmittance and a conductivity of 368 mV, indicating a potential use of cassava feedstock for ethanol production. Thus, harnessing cassava for food as well as ethanol production is deemed feasible. Such a system would, however, require supportive policies to acquire a balance between food security and fuel.

  12. Thin layer drying of cassava starch using continuous vibrated fluidized bed dryer

    Science.gov (United States)

    Suherman, Trisnaningtyas, Rona

    2015-12-01

    This paper present the experimental work and thin layer modelling of cassava starch drying in continuous vibrated fluidized bed dryer. The experimental data was used to validate nine thin layer models of drying curve. Cassava starch with 0.21 initial moisture content was dried in different air drying temperature (50°C, 55°C, 60°C, 65°C, 70°C), different weir height in bed (0 and 1 cm), and different solid feed flow (10 and 30 gr.minute-1). The result showed air dryer temperature has a significant effect on drying curve, while the weir height and solid flow rate are slightly. Based on value of R2, χ2, and RMSE, Page Model is the most accurate simulation for thin layer drying model of cassava starch.

  13. Radiosensitivity and in vitro mutagenesis in African accessions of cassava, Manihot esculenta Crantz

    International Nuclear Information System (INIS)

    Induced mutagenesis holds promise for the subtle manipulation of traits of interest in crop plants. For a vegetatively propagated crop like cassava with severe constraints posed on its genetic improvement by inherent biological systems, the adoption of this methodology seems even the more appealing. However, there is scant information on protocols for inducing mutations in this crop. We present in this report the preliminary data on the determination of radiosensitivities for some African cassava accessions. The optimal doses of gamma ray irradiation varied from as low 12 Gy to 25 Gy. The probable implication of genotypic variation in response to gamma irradiation as was found in this study buttresses the need to carry out this larger scale study in order to avail cassava scientists intending to adopt induced mutagenesis of requisite information in this regard. A modified in vitro culture medium, half strength MS without growth hormones, was also shown to greatly enhance the growth of the plantlets without producing callus. (author)

  14. Gene expression analysis during cassava defense response to bacterial blight disease

    Directory of Open Access Journals (Sweden)

    Soto-Suárez Mauricio

    2006-12-01

    Full Text Available Cassava bacterial blight (CBB caused by Xanthomonas axonopodis pv. manihotis (Xam is a destructive disease in the South América and África and yield losses range between 12 and 100%. Cytochemistry and biochemistry of defense response to CBB have been well studied. However, the response of the plant to pathogen attack at the molecular and cellular level remains uncharacterized. Identification of genes associated with defense responses is one of most critical steps leading to the elucidation of disease resistance mechanisms in cassava. In this study, we identified differentially expressed genes during pathogen attack by subtractive hybridization, using the Differential Subtraction Chain method (DSC. A population of cDNA obtained from infected plants was used as ";treatment"; and a population of cDNA obtained from healthy plants was used as ";control";. 1536 clones were isolated from the resistant varieties (MBRA 685 and SG 107-35. Of these, 110 randomly selected clones were sequenced and a homology search was conducted. The sequence analysis showed that 14 cDNA clones shared homology with plant genes involved in defense responses, 70 clones were either homologous to plant genes of unknown function or showed no homology, representing new genes potentially involved in cassava defense responses. A cDNA microarray was constructed by spotting the clones identified from our subtractive libraries. Other clones potentially involved in cassava defense responses were also included. The cassava defense cDNA microarray was used to confirm the differential expression of the clones. Keywords: cassava, bacterial blight, gene expression, subtractive library, microarrays.

  15. Non-destructive determination of photosynthetic rates of eight varieties of cassava (Manihot esculenta Crantz)

    International Nuclear Information System (INIS)

    Cassava is an important food security crop in Ghana and in the wake of climate change there is the need for plant breeders to develop varieties with high water use efficiency as well as high photosynthetic rate in order to adapt to the changing climate. Thus, the photosynthetic rates of eight cassava (Manihot esculenta Crantz) varieties were non-destructively evaluated using photosynthesis meter miniPPM300, from June 2014 to May 2015, with the aim of selecting varieties with high photosynthetic rate for future breeding programmes. The mean photosynthetic rate varied depending on the varieties ranging from 40.5 μmol/m2s in Bosom nsia to 45.2 μmol/m2s in Gbenze. However, the presence of African cassava mosaic disease (ACMD) marginally reduced the photosynthetic rate to below 40 μmol/m2s in all the varieties. Similarly, the chlorophyll content index (CCI) as measured by chlorophyll meter and spectrophotometer also varied from one variety to another; it was low in Nandom (17.9 CCI) and high in Gbenze (39.93 CCI) using the chlorophyll meter and was also reduced by the presence of the virus. Although, the stomatal density varied between the varieties it was not influenced by virus infection. Furthermore, ACMD significantly decreased the leaf surface area from 5705.8mm2 in uninfected plants to 1251.6mm2 in infected plants, consequently reducing the number and weight of tubers produced 11 month after planting (MAP). Molecular Testing of the viruses using virus specific primers JSP001/JSP002, EAB555F/EAB555R, EACMV1e/EACMV2e at 6 MAP and 11MAP, showed that the mosaic symptoms were caused by African Cassava Mosaic virus disease. Cassava varieties with high photosynthetic efficiency and low virus infection can be used in cassava improvement programmes in Ghana. (au)

  16. Determination of Juice Removal Difficulty from Mash Cake in Cassava Mash Dewatering Operation

    Directory of Open Access Journals (Sweden)

    Oladele Peter KOLAWOLE

    2012-08-01

    Full Text Available Cassava processing equipment operators have limited knowledge; this militates against the success recorded in the research so far in cassava mash dewatering. New dewatering schemes to make food processing economical to handle are in progress. Common dewatering processes use a variety of mechanical means such as screw presses and belt presses. Experiments were conducted using three samples of TMS 4(2 1425 variety while evaluating the difficulty of separating juice from mash cake. Average specific cake resistance (a of 5×1011 m/kg was obtained confirming that it is moderately easy to dewatering.

  17. Changes in scopoletin concentration in cassava chips from four varieties during storage

    DEFF Research Database (Denmark)

    Gnonlonfin, Gbemenou Joselin Benoit; Gbaguidi, Fernand; Gbenou, Joachim D.;

    2011-01-01

    The use of the root crop cassava (Manihot esculenta Crantz) is constrained by its rapid deterioration after harvesting. Chemical and spectroscopic examination earlier revealed the accumulation of the four hydroxycoumarins esculetin, esculin, scopolin and scopoletin derived from the phenylpropanoid...... pathway, during the time course of postharvest deterioration. In this investigation the scopoletin level in parenchymal samples of four cassava cultivars used in Benin, i.e. Kpaki kpika, Kpaki soan, Logoguesse kotorou and BEN 86052, was investigated by high-performance liquid chromatography (HPLC)....

  18. EXPLORING OPTIMAL FEED TO MICROBES RATIO FOR ANAEROBIC ACIDOGENIC FERMENTATION OF CASSAVA RESIDUE FROM BREWERY

    OpenAIRE

    Xinying Wang; Shuting Zhang; Jing Wang; Xiaoyan Yu; Xuebin Lu

    2012-01-01

    Cassava residue from breweries is being generated in large amounts in Guangxi Province of China, and this has potential to cause serious environmental problems if disposed of improperly. Two-stage anaerobic fermentation is a promising method for the treatment of such residue. In this study, the effect of feed to microbes ratio (F/M ratio) on the anaerobic acidogenic fermentation of cassava residue was studied to determine the optimal F/M ratio and to maximize the performance in a subsequent m...

  19. Carotenoid stability during storage of yellow gari made from biofortified cassava or with palm oil

    OpenAIRE

    Bechoff, Aurelie; Chijioke, Ugo; Tomlins, Keith I.; Govinden, Pesila; Ilona, Paul; Westby, Andrew; Boy, Erick

    2015-01-01

    The carotenoid composition of gari made from biofortified cassava (BG) was compared to that of existing gari of similar appearance but made from white cassava with added red palm oil (RPG). Storage of both yellow gari products was modelled at ambient temperatures typical of tropical areas (19-40 °C) over a 3 month-period at constant relative humidity. Carotenoid content and hence vitamin A activity of the gari products decreased markedly with time and temperature. Trans-β-carotene degradation...

  20. Leaf consumption and duration of instars of the cassava defoliator Erinnyis ello (L., 1758) (Lepidoptera, Sphingidae)

    OpenAIRE

    Dirceu Pratissoli; José Cola Zanúncio; Reginaldo Barros; Harley Nonato de Oliveira

    2002-01-01

    The objectives of this research were to evaluate leaf consumption and the developmental time of the larvae of Erynnyis ello (L., 1758) (Lepidoptera, Sphingidae) reared on cassava, in order to obtain information for the integrated management of this pest. The larvae were reared on excised cassava leaves in Petri dishes and later in gerbox, and kept in chambers at 24 ± 2 ºC and 75 ± 10% RH. The total leaf area consumed by the larva to complete its development was 589.67 cm²; each of the five in...

  1. High-resolution mapping of resistance to cassava mosaic geminiviruses in cassava using genotyping-by-sequencing and its implications for breeding.

    Science.gov (United States)

    Rabbi, Ismail Y; Hamblin, Martha T; Kumar, P Lava; Gedil, Melaku A; Ikpan, Andrew S; Jannink, Jean-Luc; Kulakow, Peter A

    2014-06-24

    Cassava mosaic disease (CMD), caused by different species of cassava mosaic geminiviruses (CMGs), is the most important disease of cassava in Africa and the Indian sub-continent. The cultivated cassava species is protected from CMD by polygenic resistance introgressed from the wild species Manihot glaziovii and a dominant monogenic type of resistance, named CMD2, discovered in African landraces. The ability of the monogenic resistance to confer high levels of resistance in different genetic backgrounds has led recently to its extensive usage in breeding across Africa as well as pre-emptive breeding in Latin America. However, most of the landraces carrying the monogenic resistance are morphologically very similar and come from a geographically restricted area of West Africa, raising the possibility that the diversity of the single-gene resistance could be very limited, or even located at a single locus. Several mapping studies, employing bulk segregant analysis, in different genetic backgrounds have reported additional molecular markers linked to supposedly new resistance genes. However, it is not possible to tell if these are indeed new genes in the absence adequate genetic map framework or allelism tests. To address this important question, a high-density single nucleotide polymorphism (SNP) map of cassava was developed through genotyping-by-sequencing a bi-parental mapping population (N=180) that segregates for the dominant monogenic resistance to CMD. Virus screening using PCR showed that CMD symptoms and presence of virus were strongly correlated (r=0.98). Genome-wide scan and high-resolution composite interval mapping using 6756 SNPs uncovered a single locus with large effect (R(2)=0.74). Projection of the previously published resistance-linked microsatellite markers showed that they co-occurred in the same chromosomal location surrounding the presently mapped resistance locus. Moreover, their relative distance to the mapped resistance locus correlated with

  2. Biological Implications in Cassava for the Production of Amylose-Free Starch: Impact on Root Yield and Related Traits

    Science.gov (United States)

    Karlström, Amanda; Calle, Fernando; Salazar, Sandra; Morante, Nelson; Dufour, Dominique; Ceballos, Hernán

    2016-01-01

    Cassava (Manihot esculenta, Crantz) is an important food security crop, but it is becoming an important raw material for different industrial applications. Cassava is the second most important source of starch worldwide. Novel starch properties are of interest to the starch industry, and one them is the recently identified amylose-free (waxy) cassava starch. Waxy mutants have been found in different crops and have been often associated with a yield penalty. There are ongoing efforts to develop commercial cassava varieties with amylose-free starch. However, little information is available regarding the biological and agronomic implications of starch mutations in cassava, nor in other root and tuber crops. In this study, siblings from eight full-sib families, segregating for the waxy trait, were used to determine if the mutation has implications for yield, dry matter content (DMC) and harvest index in cassava. A total of 87 waxy and 87 wild-type starch genotypes from the eight families were used in the study. The only significant effect of starch type was on DMC (p cassava varieties will have competitive FRYs but special efforts will be required to attain adequate DMCs. This study contributes to the limited knowledge available of the impact of starch mutations on the agronomic performance of root and tuber crops. PMID:27242813

  3. Effects of Climate Change on the Production and Profitability of Cassava in the Niger Delta Region of Nigeria

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    J. O. Ajayi

    2015-06-01

    Full Text Available Nigeria is the single largest producer of cassava in the world with the bulk of the cassava coming out from the Niger Delta region. Human, economic and agricultural activities are currently threatened in the region by vagaries in climatic factors. These vagaries affect the production and profitability of cassava. The study was therefore conducted to assess the effects of climate change on the production and profitability of cassava in the Niger Delta region of Nigeria. The study made use of a multi-stage sampling technique to select three hundred and sixty respondents across the three highest cassava-producing states (Awka Ibom, Cross Rivers and Ondo in the region. Data for the study were collected with the aid of well-structured questionnaires assisted with interview schedules. Data collected were analysed using descriptive statistics and regression model. The determinants of cassava profitability were farm size, farmers’ experience in cassava cultivation, farmers’ experience in adopting climate change coping strategies, number of climate change coping strategies adopted, costs of input materials in Naira and labour cost in Naira.

  4. An Analysis of Partial DNA Sequence of Meisa1 Gene on Sweet and Bitter Cassavas (Manihot esculenta Crantz.

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    Dewi Indriyani Roslim

    2016-04-01

    Full Text Available Sweet and bitter taste on cassava tuber is affected by starch metabolisms. Meisa1 gene is a gene in cassava (Manihot esculenta Crantz. encoding isoamylase1 enzyme involved in starch metabolisms. This study aimed to analyze partial DNA sequences of Meisa1 gene on sweet and bitter cassavas collected by Genetics Laboratory, Department Biology, Faculty of Mathematics and Natural Sciences, Riau University, Indonesia. Methods included total DNA extraction from fresh young leaves of cassava using CTAB buffer, polymerase chain reaction (PCR, electrophoresis, and sequencing. The obtained data were analyzed using MEGA software version 5. The results showed that there were nucleotide variations in the intron region, not in the exon region. The variations were caused by the transition substitution mutation (35.39% and transversion substitution mutation (64.61%. The genetic distance range between seven cassava genotypes was approximately 0% to 11%. Partial DNA sequence variations of Meisa1 gene located in intron region were unable to cluster seven cassava genotypes separately into two groups based on tuber taste.How to CiteRoslim, D., Nisa, F., & Herman, H. (2016. An Analysis of Partial DNA Sequence of Meisa1 Gene on Sweet and Bitter Cassavas (Manihot esculenta Crantz.. Biosaintifika: Journal of Biology & Biology Education, 8(1 103-110.

  5. Growth performance and carcass characteristics of feedlot Thai native × Lowline Angus crossbred steer fed with fermented cassava starch residue.

    Science.gov (United States)

    Pilajun, Ruangyote; Wanapat, Metha

    2016-04-01

    Ten Thai native × Lowline Angus crossbred (50:50) steers were used in a completely randomized design to receive two treatments including concentrate containing cassava chips (Control) and fermented cassava starch residue (FCSR) as major carbohydrate sources. FCSR was prepared as yeast (Saccharomyces cerevisiae) inoculates with exogenous enzyme addition. All steers received ad libitum rice straw and concentrate in equal proportions (1:1). Replacement of cassava chip with FCSR increased neutral detergent fiber and acid detergent fiber intakes but decreased non-protein nitrogen intake of steers. Digestibility of dry matter, organic matter, and crude protein were decreased with replacement of cassava chip by FCSR; however, digested nutrients were similar between groups. Replacement of cassava chip in the concentrate with FCSR resulted in comparable growth performance and feed efficiency of the feedlot steers. Moreover, carcass characteristics in terms of yield and meat quality of the steers were not affected by cassava chips replaced by FCSR as a major carbohydrate source in the concentrate. In conclusion, replacement of cassava chip in the concentrate with FCSR decreased feed digestibility; however, it did not impact negatively on growth performance and carcass traits of feedlot Thai native × Lowline Angus crossbred steers. PMID:26942915

  6. Genome-wide survey and expression analysis of the calcium-dependent protein kinase gene family in cassava.

    Science.gov (United States)

    Hu, Wei; Hou, Xiaowan; Xia, Zhiqiang; Yan, Yan; Wei, Yunxie; Wang, Lianzhe; Zou, Meiling; Lu, Cheng; Wang, Wenquan; Peng, Ming

    2016-02-01

    Calcium-dependent protein kinases (CPKs) play important roles in regulating plant tolerance to abiotic stress and signal transduction; however, no data are currently available regarding the CPK family in cassava. Herein, we identified 27 CPK genes from cassava based on our previous genome sequencing data. Phylogenetic analysis showed that cassava CPKs could be clustered into three groups, which was further supported by gene structure and conserved protein motif analyses. Global expression analysis suggested that MeCPK genes showed distinct expression patterns in different tissues between wild subspecies and cultivated varieties, indicating their involvement in the functional diversity of different varieties. Transcriptomics, interaction networks, and co-expression assays revealed a broad transcriptional response of cassava CPKs and CPK-mediated networks to drought stress and their differential expression profiles in different varieties, implying their contribution to drought stress tolerance in cassava. Expression analysis of eight MeCPK genes suggested a comprehensive response to osmotic stress, salt, cold, abscisic acid, and H2O2, which indicated that cassava CPKs might be convergence points for different signaling pathways. This study provides a basis for crop improvements and understanding of abiotic stress responses and signal transduction mediated by CPKs in cassava. PMID:26272723

  7. Tensile and Water Absorption Properties of Biodegradable Composites Derived from Cassava Skin/ Polyvinyl Alcohol with Glycerol as Plasticizer

    International Nuclear Information System (INIS)

    Natural organic and abundant resources biopolymers received more attention due to their low cost, availability and degradability after usage. Cassava skin was used as natural fillers to the polyvinyl alcohol (PVA). Cassava skin/ poly vinyl alcohol blends were compounded using melt extrusion twin screw extruder and test samples were prepared using the compression method. Various ratios of cassava skin and glycerol were investigated to identify suitable composition based on the water absorption and tensile properties. The water absorption of the cassava skins/ PVA samples increased at higher composition of cassava skin due to their hydrophilic properties but decrease with glycerol content. The strength of the cassava skins/ PVA samples increased with the higher composition of cassava skin up to 70 wt % while gradually decreased with the increasing composition of glycerol. The Young modulus increased with glycerol content but decreased with fibre loading up to 70 wt %. Elongation at break decreased with fibre loading and glycerol up to 70 wt % and 30 phr, respectively. (author)

  8. Effects of soya fatty acids on cassava ethanol fermentation.

    Science.gov (United States)

    Xiao, Dongguang; Wu, Shuai; Zhu, Xudong; Chen, Yefu; Guo, Xuewu

    2010-01-01

    Ethanol tolerance is a key trait of microbes in bioethanol production. Previous studies have shown that soya flour contributed to the increase of ethanol tolerance of yeast cells. In this paper, the mechanism of this ethanol tolerance improvement was investigated in cassava ethanol fermentation supplemented with soya flour or defatted soya flour, respectively. Experiment results showed that ethanol tolerance of cells from soya flour supplemented medium increased by 4-6% (v/v) than the control with defatted soya flour. Microscopic observation found that soya flour can retain the cell shape while dramatic elongations of cells were observed with the defatted soya flour supplemented medium. Unsaturated fatty acids (UFAs) compositions of cell membrane were analyzed and the UFAs amounts increased significantly in all tested strains grown in soya flour supplemented medium. Growth study also showed that soya flour stimulated the cell growth rate by approximately tenfolds at 72-h fermentation. All these results suggested that soya fatty acids play an important role to protect yeast cells from ethanol stress during fermentation process.

  9. Structure and properties of pregelatinized cassava starch/kaolin composites

    International Nuclear Information System (INIS)

    Highlights: ► Pregelatinized starch/kaolin composites were prepared using compression molding. ► The tensile strengths of the composites were higher than for thermoplastic starch. ► Degradation temperatures of the composites were higher than for thermoplastic starch. ► The retrogradation behavior of the composites was hindered by kaolin. -- Abstract: Pregelatinized cassava starch/kaolin composites were prepared using compression molding. The morphology of the fractured surfaces, retrogradation behavior, thermal decomposition temperatures and mechanical properties of the composites were investigated using scanning election microscopy (SEM), X-ray diffraction (XRD), thermal gravimetric analysis (TGA) and tensile testing, respectively. The tensile strengths and thermal degradation temperatures of the composites were higher than for thermoplastic starch (TPS). The retrogradation behavior of the composites was hindered by kaolin. The water absorption was measured after aging for 12 and 45 days at a relative humidity (RH) of 15% and 55%. It indicated that all the composites displayed lower water absorption values than TPS.

  10. Study of cassava starch enzymatic modification for maltodextrins obtention

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    Miguel Angel Díaz

    2012-05-01

    Full Text Available It was pretended to investigate the effect of the most relevant variables in cassava starch enzymatic hydrolysis process, on laboratory scale, to determine appropriate industrial conditions for the obtention of different kinds of maltodextrins. An a-Amylase enzyme, from genetically modified strain of Bacillus lichenijormis, was used to hydrolize the starch. Once the variables were chosen, an experimental fractioned factorial design was established with two levels. The Dextrose Equivalent (DE was taken as the response variable. The variables studied were: temperature (80-90°C, pH (5.5-6.5, dry-weight starch concentration (30-40% w/w, enzyme dosage (0.583-0.833 ul/g starch and calcium concentration (50-70 mgIL of CaClJ Some assays were settle in order to define the rheologic behavior and to determine the most relevant variables that affect the functional properties of the maltodextrin suspensions. Both, temperature and enzyme concentration were the variables that affect the most the initial convertion rate and the characteristics of the product convertion. For the interval of time considered, the highest DE obtained was 30 and the highest initial rate was 21.7 DE/hour. The functional properties of the maltodextrin solutions were affected by temperature and dry-weight starch concentration.

  11. Perception of Infestation Problems on Cassava Farms and Preference for Weed Management Practices in Humid Agro- Ecological Zone of Nigeria

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    Anthony Agumagu

    2008-06-01

    Full Text Available The problem of weed infestation on cassava farms is a major factor for low crop yield. This problem has caused untold hardship on the small-scale cassava farms where production at the subsistence level and where farmers still manage to produce some quantity for sale. The study examines cassava farmers’ perception of problems of infestation and preference for weed management practices in the humid agro-ecological zone of Nigeria. Data was collected with the aid of questionnaire and interviews. Random sampling technique was used to select 117 small-scale cassava farmers in the study area. Data analysis was done by simple descriptive statistics such as frequency, percentage and mean. Findings of the study revealed that majority of the respondents (73.5% grow cassava for both household use and for sale. The major source of labour identified by respondents was family labour (51.3%. About 55% of the respondents obtained cassava planting materials from the open market. Findings showed that the commonest weed control measures used by cassava farmers were hand pulling (100%, and hoes/cutlass (100%. However, the most preferred weed control measures identified include hoes/cutlass (100%, use of machines (100%, and a combination of methods (100%. Major problems affecting cassava farms as identified by respondents include grasses (88%, broadleaf weeds (66.6%, rodents (64.1%, other animals (63.3%, cassava rot (53.9% and insect pests (48.7%. Extension education should focus on the preferred weed control measures identified by respondents so as to work out modalities for their adequate use. This can be possible if regular extension farmer forum is ensured.

  12. Diversity of LTR-retrotransposons and Enhancer/Suppressor Mutator-like transposons in cassava (Manihot esculenta Crantz).

    Science.gov (United States)

    Gbadegesin, Michael A; Wills, Matthew A; Beeching, John R

    2008-10-01

    Cassava (Manihot esculenta Crantz), though a major world crop with enormous potential, is very under studied. Little is known about its genome structure and organisation. Transposable elements have a key role in the evolution of genome structure, and can be used as important tools in applied genetics. This paper sets out to survey the diversity of members of three major classes of transposable element within the cassava genome and in relation to similar elements in other plants. Members of two classes of LTR-retrotransposons, Ty1/copia-like and Ty3/gypsy-like, and of Enhancer/Suppressor Mutator (En/Spm)-like transposons were isolated and characterised. Analyses revealed 59 families of Ty1/copia, 26 families of Ty3/gypsy retrotransposons, and 40 families of En/Spm in the cassava genome. In the comparative analyses, the predicted amino acid sequences for these transposon classes were compared with those of related elements from other plant species. These revealed that there were multiple lineages of Ty1/copia-like retrotransposons in the genome of cassava and suggested that vertical and horizontal transmission as the source of cassava Mecops may not be mutually exclusive. For the Ty3/gypsy elements network, two groups of cassava Megyps were evident including the Arabidopsis Athila lineage. However, cassava En/Spm-like elements (Meens) constituted a single group within a network of plant En/Spm-like elements. Hybridisation analysis supported the presence of transposons in the genome of cassava in medium (Ty3/gypsy and En/Spm) to high (Ty1/copia) copy numbers. Thus the cassava genome was shown to contain diverse members of three major classes of transposable element; however, the different classes exhibited contrasting evolutionary histories.

  13. The effect of cassava-based bioethanol production on above-ground carbon stocks: A case study from Southern Mali

    International Nuclear Information System (INIS)

    Increasing energy use and the need to mitigate climate change make production of liquid biofuels a high priority. Farmers respond worldwide to this increasing demand by converting forests and grassland into biofuel crops, but whether biofuels offer carbon savings depends on the carbon emissions that occur when land use is changed to biofuel crops. This paper reports the results of a study on cassava-based bioethanol production undertaken in the Sikasso region in Southern Mali. The paper outlines the estimated impacts on above-ground carbon stocks when land use is changed to increase cassava production. The results show that expansion of cassava production for bioethanol will most likely lead to the conversion of fallow areas to cassava. A land use change from fallow to cassava creates a reduction in the above-ground carbon stocks in the order of 4–13 Mg C ha−1, depending on (a) the age of the fallow, (b) the allometric equation used and (c) whether all trees are removed or the larger, useful trees are preserved. This ‘carbon debt’ associated with the above-ground biomass loss would take 8–25 years to repay if fossil fuels are replaced with cassava-based bioethanol. - Highlights: ► Demands for biofuels make production of cassava-based bioethanol a priority. ► Farmers in Southern Mali are likely to convert fallow areas to cassava production. ► Converting fallow to cassava creates reductions in above-ground carbon stocks. ► Estimates of carbon stock reductions include that farmers preserve useful trees. ► The carbon debt associated with above-ground biomass loss takes 8–25 years to repay.

  14. Diversity of begomoviruses associated with mosaic disease of cultivated cassava (Manihot esculenta Crantz) and its wild relative (Manihot glaziovii Mull. Arg.) in Uganda.

    Science.gov (United States)

    Sserubombwe, W S; Briddon, R W; Baguma, Y K; Ssemakula, G N; Bull, S E; Bua, A; Alicai, T; Omongo, C; Otim-Nape, G W; Stanley, J

    2008-07-01

    Cassava (Manihot esculenta) growing in Uganda during 2001-2002 has been screened for the presence of begomoviruses using PCR-RFLP, cloning full-length genomic components and nucleotide sequence analysis. In contrast with a recent survey in neighbouring Kenya, which identified three distinct strains of East African cassava mosaic virus (EACMV, EACMV-UG and EACMV-KE2) as well as East African cassava mosaic Zanzibar virus and the new species East African cassava mosaic Kenya virus, only EACMV-UG and, to a lesser extent, African cassava mosaic virus (ACMV) were found associated with cassava in Uganda. The integrity of the cloned genomic components of representative virus isolates was confirmed by demonstrating their infectivity in Nicotiana benthamiana and cassava using biolistic inoculation, providing a convenient means to screen cassava varieties for disease resistance. Both EACMV-UG and ACMV were also associated with Manihot glaziovii. Infectivity studies using cloned components confirmed that viruses from one host could infect the other, suggesting that this wild relative of cassava might be a reservoir host for the disease. The relatively low level of diversity of begomoviruses associated with cassava mosaic disease in Uganda is consistent with reports that EACMV-UG has displaced other begomovirus species and strains during the recent epidemic that swept through the country.

  15. The effect of chemical treatments on the pH & microbial flora of cassava residues during storage

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    Thaísa Anders Carvalho Souza

    2013-09-01

    Full Text Available Cassava starch factories produce residues that can be commercialized as food ingredients. The objective of this study was to evaluate the microbiological safety of cassava peel and bagasse during storage, with and without chemical treatment. The bagasse was acidified with lactic acid, and the peel was immersed in a sodium hypochlorite solution. The microbiological analyses were carried out for 72 h after harvest. All of the samples showed the absence of pathogenic microorganisms, and the acidification and sanitization were effective in controlling total coliforms. Cassava bagasse and peel samples can be considered safe for consumption by humans as ingredients for other food products.

  16. Structural and Digestion Properties of Soluble-, Slowly Digestible and Resistant Maltodextrin from Cassava Starch by Enzymatic Modification

    DEFF Research Database (Denmark)

    Sorndech, Waraporn

    The combination of branching enzyme (BE) and amylomaltase (AM) were selected to modify cassava starch. AM were used to elongate the glucan chains in order to enhance BE activity to create branching linkages. Cassava starch were gelatinized and incubated with BE or AMBE or BEAMBE or simultaneous......) production was prepared by using simultaneous α-amylase and BE followed by α- transglucosidase (ABT) and simultaneous α-amylase and BE followed by simultaneous β-amylase and α-transglucosidase (ABbT) with 30% and 50% (w/v) cassava starch substrate concentration. ABT catalysis showed branching linkages...

  17. Biofortified cassava with pro-vitamin A is sensory and culturally acceptable for consumption by primary school children in Kenya.

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    Elise F Talsma

    Full Text Available BACKGROUND: Biofortification of cassava with pro-vitamin A can potentially reduce vitamin A deficiency in low-income countries. However, little is known about consumer acceptance of this deep yellow variety of cassava compared to the commonly available white varieties. We aimed to determine the sensory and cultural acceptability of the consumption of pro-vitamin A rich cassava in order to identify key factors predicting the intention to consume pro-vitamin A rich cassava by families with school-aged children in Eastern Kenya. METHODS: Sensory acceptability was measured by replicated discrimination tests and paired preference tests among 30 children (7-12 yr and 30 caretakers (18-45 yr in three primary schools. Cultural acceptability was assessed with a questionnaire based on the combined model of The Theory of Planned Behavior and The Health Belief Model in one primary school among 140 caretakers of children aged 6 to 12 years. Correlations and multivariate analyses were used to determine associations between summed scores for model constructs. RESULTS: Caretakers and children perceived a significant difference in taste between white and pro-vitamin A rich cassava. Both preferred pro-vitamin A rich cassava over white cassava because of its soft texture, sweet taste and attractive color. Knowledge about pro-vitamin A rich cassava and it's relation to health ('Knowledge' ((β = 0.29, P = <.01 was a strong predictor of 'Health behavior identity'. Worries related to bitter taste and color ('Perceived barriers 1' (β = -0.21, P = .02, the belief of the caretaker about having control to prepare cassava ('Control beliefs' (β = 0.18, P = .02 and activities like information sessions about pro-vitamin A rich cassava and recommendations from health workers ('Cues to action'(β = 0.51, P = <.01 were the best predictors of intention to consume pro-vitamin A rich cassava. CONCLUSIONS: Pro-vitamin A rich cassava is well

  18. Study on Development of Cassava Industry in Guizhou%贵州木薯产业发展研究

    Institute of Scientific and Technical Information of China (English)

    欧珍贵; 黎青; 罗亚红; 田大清; 周正邦

    2011-01-01

    By analyzing the current situation of the scientific research and production, the feasibility of developing cassava industry and the existent problems in the development of cassava industry in Guizhou, the author puts forward the developmental strategy of cassava industry in Guizhou.%通过对贵州的科研生产现状、贵州发展木薯的可行性及贵州木薯发展存在的问题进行分析,提出了贵州木薯产业的发展策略,旨在为贵州木薯产业发展提供决策参考.

  19. Determination of aflatoxin in processed dried cassava root: validation of a new analytical method for cassava flour.

    Science.gov (United States)

    Gnonlonfin, G J Benoit; Katerere, David R; Adjovi, Yann; Brimer, Leon; Shephard, Gordon S; Sanni, Ambaliou

    2010-01-01

    A new method that uses HPLC with a photochemical reactor for enhanced detection was developed and validated for the determination of aflatoxins in cassava flour. Samples were spiked with a mixture of four aflatoxins at 5, 10, and 20 microg/kg mixed with either 1 or 5 g NaCI and extracted with methanol-water (80 + 20, v/v) by shaking for 10 or 30 min. An immunoaffinity column was used for cleanup. HPLC with postcolumn derivatization, for enhancement of aflatoxin fluorescence, and fluorescence determination were used for quantitation of the toxin concentration. The method was validated for recovery, linearity, and precision at the three concentrations tested. Recovery ranges were 52-70, 69-85, and 80-89% for the spiking levels of 5.0, 10.0, and 20.0 microg/kg, respectively. It appears that the amount of salt (NaCl) and the shaking time are critical factors in this method; optimal performance was obtained when 1 g salt was used and the shaking time was 10 min. The good linearity and precision of the method allowed baseline separation from interferences, e.g., coumarins. PMID:21313816

  20. AGROECOSYSTEMS SUSTAINABILITY OF CASSAVA PRODUCTION OF PARAÍBA RURAL AREA FROM THE PERSPECTIVE OF BIOGRAM

    Directory of Open Access Journals (Sweden)

    Valdenildo Pedro da Silva

    2015-08-01

    Full Text Available Agriculture modernization resulting from green revolution occurred through means of diverse technological innovations as soluble fertilizers, pesticides, agricultural machinery and genetically modified seeds, aimed at increasing food production. However, the indiscriminate use of these innovations by farmers has been highlighted numerous environmental problems, affecting the productive agricultural system. This technological innovations reality and environmental obstacles, is also been experienced by cassava production in Paraíba rural area. Therefore, this study tried to assess the agroecosystems sustainability of cassava production (Manihot esculenta Crantz of Paraíba Rural Mesoregion, using Sustainable Development Index (S³ method, and its graphical representation, the Biogram. The results showed sustainability differences between the agroecosystems of investigated municipalities, of which Araçagi showed stable levels of sustainability, Araruna and Bananeiras demonstrated unstable levels, and Puxinanã showed the most critical sustainably level. It was concluded that, even the agroecosystems of Araçagi municipality showing better levels of sustainability, when compared with other municipalities assessed, cassava production showed unsustainability situations regarding its technological innovation levels, average yield of cassava production, land in erosion process, water scarcity and lack of social participation.

  1. Technical and Socioeconomic Potential of Biogas from Cassava Waste in Ghana

    Directory of Open Access Journals (Sweden)

    Francis Kemausuor

    2015-01-01

    Full Text Available This study analyses technical potential and ex ante socioeconomic impacts of biogas production using cassava waste from agroprocessing plants. An analysis was performed for two biodigesters in two cassava processing communities in Ghana. The results showed that the two communities generate an excess of 4,500 tonnes of cassava peels per year. Using approximately 5% of the peels generated and livestock manure as inoculum can generate approximately 75,000 m3 of gas with an estimated 60% methane content from two separate plants of capacities 500 m3 and 300 m3 in the two communities. If used internally as process fuel, the potential gas available could replace over 300 tonnes of firewood per year for cassava processing. The displacement of firewood with gas could have environmental, economic, and social benefits in creating sustainable development. With a 10 percent discount rate, an assumed 20-year biodigester will have a Net Present Value of approximately US$ 148,000, 7-year Payback Period, and an Internal Rate of Return of 18.7%. The project will create 10 full-time unskilled labour positions during the investment year and 4 positions during operation years.

  2. Effect of Hydrocolloids and Emulsifiers on Baking Quality of Composite Cassava-Maize-Wheat Breads

    Directory of Open Access Journals (Sweden)

    Maria Eduardo

    2014-01-01

    Full Text Available Cassava is widely available worldwide but bread quality is impaired when cassava is used in the bread formulation. To overcome this problem, different improvers were tested in the preparation of composite cassava-maize-wheat (CMW breads. Emulsifiers, diacetyl tartic acid ester of monoglycerides (DATEM, sodium stearoyl-2-lactylate (SSL, and lecithin (LC; and hydrocolloids, carboxymethylcellulose (CMC and high-methylated pectin (HM pectin were added during dough preparation of the composite flours (cassava-maize-wheat, 40 : 10 : 50. Each emulsifier was tested in combination with the hydrocolloids at levels of 0.1, 0.3, and 0.5% while hydrocolloids were used at a level of 3%. Bread quality attributes such as specific loaf volume, crust colour, crumb moisture, and firmness were measured. The specific volume of the fresh breads significantly improved with the addition of hydrocolloids (7.5 and 13% and in combination with emulsifiers (from 7.9 to 27% compared with bread produced without improvers. A significant improvement of brownness index and firmness of the composite flours breads was achieved with the addition of hydrocolloids and emulsifiers. The results show that emulsifiers and hydrocolloids can significantly improve the baking quality of CMW breads and thereby enhance the potential for using locally produced flours in bread baking.

  3. Cassava Ivorian bacilliform virus is a member of the genus Anulavirus.

    Science.gov (United States)

    Scott, Simon W; MacFarlane, Stuart A; McGavin, Wendy J; Fargette, Denis

    2014-10-01

    The complete genomic sequence of Cassava Ivorian bacilliform virus (CIBV) is described. The virus has a genomic organization similar to that of pelargonium zonate spot virus (PZSV), the type member of the genus Anulavirus, but it is most closely related to a second, recently described, anulavirus, Amazon lily mild mottle virus (ALiMMV). PMID:24838850

  4. EXPLORING OPTIMAL FEED TO MICROBES RATIO FOR ANAEROBIC ACIDOGENIC FERMENTATION OF CASSAVA RESIDUE FROM BREWERY

    Directory of Open Access Journals (Sweden)

    Xinying Wang,

    2012-01-01

    Full Text Available Cassava residue from breweries is being generated in large amounts in Guangxi Province of China, and this has potential to cause serious environmental problems if disposed of improperly. Two-stage anaerobic fermentation is a promising method for the treatment of such residue. In this study, the effect of feed to microbes ratio (F/M ratio on the anaerobic acidogenic fermentation of cassava residue was studied to determine the optimal F/M ratio and to maximize the performance in a subsequent methanogenic stage. The experiments were carried out at the F/M ratios of 0.2, 0.61, 1.02, 2.05, 3.07, and 4.09 g cassava-TS/g sludge-VSS in six laboratory-scale, completely stirred, tank reactors (CSTR at mesophilic temperature (35°C. An F/M ratio of 1.02 g cassava-TS/g sludge-VSS resulted in the highest solid removal efficiency and VFA/COD ratio, while starch removal efficiency was still near 100 percent, and acidification was relatively high. As a further benefit, the VFA distribution was more suitable for the subsequent methanogenic fermentation stage.

  5. Exploratory studies on the carboxymethylation of cassava starch in water-miscible organic media

    NARCIS (Netherlands)

    Yao, J; Chen, WR; Manurung, RM; Ganzeveld, KJ; Heeres, HJ; Manurung, Robbert M.; Chen, Wen-ren

    2004-01-01

    The carboxymethylation of cassava starch using sodium monochloroacetate (SMCA) as an etherification agent was investigated. Mixtures of water and water-miscible organic liquids were selected as carboxymethylation reaction medium to obtain a high degree of substitution (DS) without changing the granu

  6. Augmenting Iron Accumulation in Cassava by the Beneficial Soil Bacterium Bacillus subtilis (GBO3

    Directory of Open Access Journals (Sweden)

    Monica A Freitas

    2015-08-01

    Full Text Available Cassava (Manihot esculenta, a major staple food in the developing world, provides a basic carbohydrate diet for over half a billion people living in the tropics. Despite the iron abundance in most soils, cassava provides insufficient iron for humans as the edible roots contain 3-12 times less iron than other traditional food crops such as wheat, maize, and rice. With the recent identification that the beneficial soil bacterium Bacillus subtilis (strain GB03 activates iron acquisition machinery to increase metal ion assimilation in Arabidopsis, the question arises as to whether this plant-growth promoting rhizobacterium (PGPR also augments iron assimilation to increase endogenous iron levels in cassava. Biochemical analyses reveal that shoot-propagated cassava with GB03-inoculation exhibit elevated iron accumulation after 140 days of plant growth as determined by X-ray microanalysis and total foliar iron analysis. Growth promotion and increased photosynthetic efficiency were also observed for greenhouse-grown plants with GB03-exposure. These results demonstrate the potential of microbes to increase iron accumulation in an important agricultural crop and is consistent with idea that microbial signaling can regulate plant photosynthesis.

  7. Physicochemical and microbiological characterization of cassava flower honey samples produced by africanized honeybees

    Directory of Open Access Journals (Sweden)

    Lucimar Peres de Moura Pontara

    2012-09-01

    Full Text Available Cassava producers in the region of Marília-São Paulo are integrating their farming activity with beekeeping to diversify their income. The aim of this study was to evaluate the physicochemical and microbiological quality of honey samples produced by Africanized honeybees Apis mellifera from cassava flower in 2008. Analysis were carried out for pH, total soluble solids (TSS, acidity, moisture, reducing and total sugars, apparent sucrose, hydroxymethylfurfural, color, ash, proteins, water insoluble solids, diastasic activity, mineral content, microbiological evaluations, and mineral and hydrocyanic acid (HCN content. The honey samples showed physicochemical and microbiological characteristics favorable to commercialization, with the exception of apparent sucrose and acidity, which show the need for a narrow focus of attention to the honey maturation degree at the harvest time and more careful monitoring during production and processing. The commercialization of Brazilian cassava honey, still little explored, can be widely spread in the market since the levels of hydrocyanic acid (HCN showed no consumption risk; in addition the simultaneous production of honey and cassava provides an alternative to family income increase.

  8. CASSAVA ENTREPRENEURSHIP AND GENDER PARTICIPATION IN UDI LOCAL GOVERNMENT AREA OF ENUGU STATE, NIGERIA

    Directory of Open Access Journals (Sweden)

    Christopher Ogbonna EMEROLE

    2014-04-01

    Full Text Available This Study on cassava entrepreneurship and gender participation was carried out in Udi local Government Area of Enugu State, Nigeria. Quarterly data from a panel of thirty male-headed and thirty female-headed cassava-based farm households randomly selected followings a multistage sampling of ten out of 24 autonomous communities of the study area was subjected to descriptive and inferential statistical analyses. Both male and female entrepreneurs engaged more on three of cassava products namely Garri, Fufu and Tapioca on account of relatively better profits from them. Segregating male from female entrepreneurs, participation of males in cassava enterprise was negatively influenced by adult number of males, time spent on housework, and daily non-farm wage while participation of females in the enterprise was influenced by adult number of females in household, daily non-farm wage, time spent on housework and frequency of contact with extension agency with challenges of high operational costs, and poor packaging on the enterprise in the area. To bring male and female entrepreneurs at par in terms of resource needs, all social and cultural constraints on female access to arable land and credit should be addressed by law such that that there will be prohibition against any discrimination on women. We recommended provision of financial credit and grants for SMEs development to enable entrepreneurs (especially women purchase fertilizers and automated machines for processing, and packaging of the products to attract better prices.

  9. Modelling potential ß-carotene intake and cyanide exposure from consumption of biofortified cassava

    Science.gov (United States)

    Background: Vitamin A (VA) deficiency causes disability and mortality. Cassava, a staple crop in Africa, can be crossbred to improve its pro-vitamin A (PVA) content and used as an alternative to capsule supplementation. However it contains cyanide and its continued consumption may lead to chronic...

  10. Removal of Cu (II and Zn (II from water with natural adsorbents from cassava agroindustry residues

    Directory of Open Access Journals (Sweden)

    Daniel Schwantes

    2015-07-01

    Full Text Available Current study employs solid residues from the processing industry of the cassava (Manihot esculenta Crantz (bark, bagasse and bark + bagasse as natural adsorbents for the removal of metal ions Cu(II and Zn(II from contaminated water. The first stage comprised surface morphological characterization (SEM, determination of functional groups (IR, point of zero charge and the composition of naturally existent minerals in the biomass. Further, tests were carried out to evaluate the sorption process by kinetic, equilibrium and thermodynamic studies. The adsorbents showed a surface with favorable adsorption characteristics, with adsorption sites possibly derived from lignin, cellulose and hemicellulose. The dynamic equilibrium time for adsorption was 60 min. Results followed pseudo-second-order, Langmuir and Dubinin-Radushkevich models, suggesting a chemisorption monolayer. The thermodynamic parameters suggested that the biosorption process of Cu and Zn was endothermic, spontaneous or independent according to conditions. Results showed that the studied materials were potential biosorbents in the decontamination of water contaminated by Cu(II and Zn(II. Thus, the above practice complements the final stages of the cassava production chain of cassava, with a new disposal of solid residues from the cassava agroindustry activity.

  11. The production-ecological sustainability of cassava, sugarcane and sweet sorghum cultivation for bioethanol in Mozambique

    NARCIS (Netherlands)

    Vries, de S.C.; Ven, van de G.W.J.; Ittersum, van M.K.; Giller, K.E.

    2012-01-01

    We present an approach for providing quantitative insight into the production-ecological sustainability of biofuel feedstock production systems. The approach is based on a simple crop-soil model and was used for assessing feedstock from current and improved production systems of cassava for bioethan

  12. Analysis of the potential for sustainable, cassava-based bioethanol production in Mali

    DEFF Research Database (Denmark)

    Rasmussen, Kjeld; Bruun, Thilde Bech; Birch-Thomsen, Torben;

    The present project is covered in five main reports: 1) Analyses of the potential for sustainable, cassava-based bio-ethanol production in Mali 2) Agricultural residues for energy production in Mali 3) Pre-feasibility study for an electric power plant based on rice straw 4) Estimation of wind...

  13. Behavior of Fermentable Sugars in the Traditional Production Process of Cassava Bioethanol

    Directory of Open Access Journals (Sweden)

    P. Diakabana

    2014-10-01

    Full Text Available The aim of study is to evaluate the ferment ability of cassava must in the ethanol production process from cassava in Congo. Three traditional methods of ethyl fermentation were tested: spontaneous fermentation, fermentation with yeast inoculation and fermentation led with yeasting and sugaring. Consumption of fermentable sugars was further in the case of directed fermentation with yeast inoculation (3° Brix residual extract from 48 h compared to spontaneous fermentation without yeast inoculation (3.8° Brixresidual extract from 120 heures. Total sugars have been consumed only partially (66.7% of limit attenuation, while reducing sugars have been almost completely (about 91%. The addition of yeast in the cassava wort have led to a lower assessment of dextrins (2.7% glucose equivalent compared to spontaneous fermentation (3.6%. It have also assured a better overall ethanol productivity PTE= 0.83 g ethanol/L.h than sugaring proceeding (PTE = 0.61 g/L.h and without yeast additional (PTE = 0.32 g/L.h. Among the fermentable sugars developed in the cassava mash there are reducing sugars, such as glucose and maltose. Non-fermentable sugars represent a significant slice of stock of soluble carbohydrate (on average 3.24% dextrose equivalent of the must in the three cases of fermentation tested.

  14. Process for producing cassava hydroxypropyl distarch phosphate and study of the properties

    Institute of Scientific and Technical Information of China (English)

    邵亚东; 王艳楠; 刘大伟; 刘晓成

    2014-01-01

    In the experiment, the nature cassava starch reacted with 1,2-epoxypropane and sodium trimetaphosphate under basic condition to producing hydroxypropyl distarch phosphate.At same time ,prepared to researching characteristics of the starch, including the substitution degree, gelatinization temperature and peak viscosity.

  15. Development of retrotransposon-based markers IRAP and REMAP for cassava (Manihot esculenta).

    Science.gov (United States)

    Kuhn, B C; Mangolin, C A; Souto, E R; Vicient, C M; Machado, M F P S

    2016-04-07

    Retrotransposons are abundant in the genomes of plants. In the present study, inter-retrotransposon amplified polymorphism (IRAP) and retrotransposon-microsatellite amplified polymorphism (REMAP) markers were developed for the cassava genome (Manihot esculenta Crantz). Four cassava cultivars (Fécula Branca, IPR-União, Olho Junto, and Tamboara, two samples per cultivar) were used to obtain IRAP and REMAP fingerprints. Twelve designed primers were amplified alone and in combinations. The 42 IRAP/REMAP primer combinations amplified 431 DNA segments (bands; markers) of which 36 (8.36%) were polymorphic. The largest number of informative markers (16) was detected using the primers AYF2 and AYF2xAYF4. The number of bands for each primer varied from 3 to 16, with an average of 10.26 amplified segments per primer. The size of the amplified products ranged between 100 and 7000 bp. The AYF2 primer generated the highest number of amplified segments and showed the highest number of polymorphic bands (68.75%). Two samples of each cassava cultivar were used to illustrate the usefulness and the polymorphism of IRAP/REMAP markers. IRAP and REMAP markers produced a high number of reproducible bands, and might be informative and reliable for investigation of genetic diversity and relationships among cassava cultivars.

  16. Identification and distribution of the NBS-LRR gene family in the cassava genome

    Science.gov (United States)

    Plant resistance genes (R genes) exist in large families and usually contain both a nucleotide-binding site domain and a leucine-rich repeat domain, denoted NBS-LRR. The genome sequence of cassava (Manihot esculenta) is a valuable resource for analyzing the genomic organization of resistance genes i...

  17. Market impact on cassava's development potential in the Atlantic Coast region of Colombia.

    NARCIS (Netherlands)

    Janssen, W.G.

    1986-01-01

    The impact of markets on agricultural development was analyzed by means of a case study on cassava in the Atlantic Coast region of Colombia. In the development process, the demand for agricultural products changes considerably. Traditional food products, such as roots and tubers, face a decreasing d

  18. Bulk H analysis using neutrons for routine quality control of cassava and products

    Energy Technology Data Exchange (ETDEWEB)

    Jonah, S.A., E-mail: jonahsa2001@yahoo.co [Centre for Energy Research and Training, Ahmadu Bello University, Zaria (Nigeria); Okunade, I.O. [Centre for Energy Research and Training, Ahmadu Bello University, Zaria (Nigeria); Abolude, O. [Department of Physics, Ahmadu Bello University, Zaria (Nigeria); Onyike, E.; Inuwa, I.M. [Department of Biochemistry, Ahmadu Bello University, Zaria (Nigeria)

    2011-07-15

    Nuclear and related techniques are useful in addressing the issues of food security and safety facing the world today, via quality control of raw materials and products. In this work, experimental investigations were performed to assess the use of total hydrogen content in cassava and products as a quality control indicator of starch and cyanide contents. The work was carried out using a neutron reflection facility at the Centre for Energy Research and Training, Ahmadu Bello University, Zaria, Nigeria. Cassava samples and products were obtained from retail outlets of Ibadan, Umudike and Zaria, representing three major regions of Nigeria. In general, data obtained indicate a total hydrogen content range of 4.47{+-}0.11-10.71{+-}0.27 wt% for the various samples, including raw, dry and processed cassava. Results show that samples having low hydrogen content are generally rich in cyanide compounds and demonstrate an inverse relationship between hydrogen content and cyanide content. The implication of this is that the neutron reflection facility can be used as a quality control setup for routine determination of hydrogen as an indicator of the cyanide content in cassava and products.

  19. Preparation and physico-chemical properties of hydrogels from carboxymethyl cassava starch crosslinked with citric acid

    Science.gov (United States)

    Boonkham, Sasikan; Sangseethong, Kunruedee; Chatakanon, Pathama; Niamnuy, Chalida; Nakasaki, Kiyohiko; Sriroth, Klanarong

    2014-06-01

    Recently, environmentally friendly hydrogels prepared from renewable bio-based resources have drawn significant attention from both industrial and academic sectors. In this study, chemically crosslinked hydrogels have been developed from cassava starch which is a bio-based polymer using a non-toxic citric acid as a crosslinking agent. Cassava starch was first modified by carboxymethylation to improve its water absorbency property. The carboxymethyl cassava starch (CMCS) obtained was then crosslinked with citric acid at different concentrations and reaction times. The gel fraction of hydrogels increased progressively with increasing citric acid concentration. Free swelling capacity of hydrogels in de-ionized water, saline solution and buffers at various pHs as well as absorption under load were investigated. The results revealed that swelling behavior and mechanical characteristic of hydrogels depended on the citric acid concentration used in reaction. Increasing citric acid concentration resulted in hydrogels with stronger network but lower swelling and absorption capacity. The cassava starch hydrogels developed were sensitive to ionic strength and pH of surrounding medium, showing much reduced swelling capacity in saline salt solution and acidic buffers.

  20. Efficient production of transgenic plants by Agrobacterium-mediated transformation of cassava (Manihot esculenta Crantz)

    NARCIS (Netherlands)

    Schreuder, M.M.; Raemakers, C.J.J.M.; Jacobsen, E.; Visser, R.G.F.

    2001-01-01

    An efficient and reproducible method was developed for Agrobacterium-mediated transformation of embryogenic suspension cultures of cassava. LBA4404(pTOK233), containing the nptII, hph and gus marker genes, was used in the experiments. Chemical selection by means of kanamycin was used to establish 10

  1. Stoking residue from extraction of cassava starch without the use of storage technologies

    Directory of Open Access Journals (Sweden)

    Cleovani Rossi Javorski

    2015-03-01

    Full Text Available The purpose of this paper was to study the storage of the residue from the extraction of cassava starch without the use of storage technologies, through chemical evaluation, pH values, temperature, development of microorganisms and mycotoxins. A randomized block design was used with eight treatments (different storage periods: 0, 3, 6, 9, 12, 15, 18 and 21 days and five replications. There was a significant difference for DM content, as a function of days in storage. The chemical composition of the residue from the extraction of cassava starch did not changed throughout the storage period. A negative linear effect was obtained for the pH values, which decreased with days in storage. There was significance of the storage period only for the fungus and yeast population, which increased up to 17 days of storage, with subsequent reduction. Mycotoxins were detected in the residue from the extraction of cassava starch. Despite it did not showed changes in the chemical composition the storage of residue from the extraction of cassava starch for 21 days proved to be an inefficient preservation process, due to the development of molds and mycotoxins

  2. Bulk H analysis using neutrons for routine quality control of cassava and products

    International Nuclear Information System (INIS)

    Nuclear and related techniques are useful in addressing the issues of food security and safety facing the world today, via quality control of raw materials and products. In this work, experimental investigations were performed to assess the use of total hydrogen content in cassava and products as a quality control indicator of starch and cyanide contents. The work was carried out using a neutron reflection facility at the Centre for Energy Research and Training, Ahmadu Bello University, Zaria, Nigeria. Cassava samples and products were obtained from retail outlets of Ibadan, Umudike and Zaria, representing three major regions of Nigeria. In general, data obtained indicate a total hydrogen content range of 4.47±0.11-10.71±0.27 wt% for the various samples, including raw, dry and processed cassava. Results show that samples having low hydrogen content are generally rich in cyanide compounds and demonstrate an inverse relationship between hydrogen content and cyanide content. The implication of this is that the neutron reflection facility can be used as a quality control setup for routine determination of hydrogen as an indicator of the cyanide content in cassava and products.

  3. Data supporting the role of enzymes and polysaccharides during cassava postharvest physiological deterioration.

    Science.gov (United States)

    Uarrota, Virgílio Gavicho; Moresco, Rodolfo; Schmidt, Eder Carlos; Bouzon, Zenilda Laurita; da Costa Nunes, Eduardo; de Oliveira Neubert, Enilto; Peruch, Luiz Augusto Martins; Rocha, Miguel; Maraschin, Marcelo

    2016-03-01

    This data article is referred to the research article entitled The role of ascorbate peroxidase, guaiacol peroxidase, and polysaccharides in cassava (Manihot esculenta Crantz) roots under postharvest physiological deterioration by Uarrota et al. (2015). Food Chemistry 197, Part A, 737-746. The stress duo to PPD of cassava roots leads to the formation of ROS which are extremely harmful and accelerates cassava spoiling. To prevent or alleviate injuries from ROS, plants have evolved antioxidant systems that include non-enzymatic and enzymatic defence systems such as ascorbate peroxidase, guaiacol peroxidase and polysaccharides. In this data article can be found a dataset called "newdata", in RData format, with 60 observations and 06 variables. The first 02 variables (Samples and Cultivars) and the last 04, spectrophotometric data of ascorbate peroxidase, guaiacol peroxidase, tocopherol, total proteins and arcsined data of cassava PPD scoring. For further interpretation and analysis in R software, a report is also provided. Means of all variables and standard deviations are also provided in the Supplementary tables ("data.long3.RData, data.long4.RData and meansEnzymes.RData"), raw data of PPD scoring without transformation (PPDmeans.RData) and days of storage (days.RData) are also provided for data analysis reproducibility in R software. PMID:26900596

  4. Development of retrotransposon-based markers IRAP and REMAP for cassava (Manihot esculenta).

    Science.gov (United States)

    Kuhn, B C; Mangolin, C A; Souto, E R; Vicient, C M; Machado, M F P S

    2016-01-01

    Retrotransposons are abundant in the genomes of plants. In the present study, inter-retrotransposon amplified polymorphism (IRAP) and retrotransposon-microsatellite amplified polymorphism (REMAP) markers were developed for the cassava genome (Manihot esculenta Crantz). Four cassava cultivars (Fécula Branca, IPR-União, Olho Junto, and Tamboara, two samples per cultivar) were used to obtain IRAP and REMAP fingerprints. Twelve designed primers were amplified alone and in combinations. The 42 IRAP/REMAP primer combinations amplified 431 DNA segments (bands; markers) of which 36 (8.36%) were polymorphic. The largest number of informative markers (16) was detected using the primers AYF2 and AYF2xAYF4. The number of bands for each primer varied from 3 to 16, with an average of 10.26 amplified segments per primer. The size of the amplified products ranged between 100 and 7000 bp. The AYF2 primer generated the highest number of amplified segments and showed the highest number of polymorphic bands (68.75%). Two samples of each cassava cultivar were used to illustrate the usefulness and the polymorphism of IRAP/REMAP markers. IRAP and REMAP markers produced a high number of reproducible bands, and might be informative and reliable for investigation of genetic diversity and relationships among cassava cultivars. PMID:27173210

  5. Concentrations of radionuclides in cassava growing in high background radiation area and their transfer

    International Nuclear Information System (INIS)

    The concentrations of several natural radionuclides in common cassava (Manihot esculenta Crantz) growing in Yangjiang County, a high background radiation area in Guangdong Province, and their uptake from soil and distribution in the plant were investigated. The results show that the concentrations of natural uranium and thorium in cassava root are of the order of 10-6 g/kg, and those of radium-226, radium-228, lead-210 and polonium-210 are of the order of 10-11 Ci/kg. The highest level is 9.30 +- 0.30 x 10-11 Ci/kg (lead-210), and the lowest is 3.99 +- 0.20 x 10-11 Ci/kg (radium-226). The levels of natural uranium, thorium, radium-226 and polonium-210 in cassava are below the limits stipulated by the regulations for food hygiene in China, while the lead-210 level approaches the limit. It is noticeable that the highest level of radium-228 is 7.28 +- 1.03 x 10-11 Ci/kg, 10.4 times higher than the limit. The transfer of all he nuclides from soil to different parts of cassava shows a pattern contrary to that of he nuclides in the other regions where uranium-and radium-containing waste water and phosphate fertilizer are used in agriculture

  6. Anaerobic co-digestion of cyanide containing cassava pulp with pig manure.

    Science.gov (United States)

    Glanpracha, Naraporn; Annachhatre, Ajit P

    2016-08-01

    Anaerobic co-digestion of cyanide-containing cassava pulp with pig manure was evaluated using laboratory scale mesophilic digester. The digester was operated in a semi-continuous mode with the mixed feedstock having C/N ratio of 35:1. Digester startup was accomplished in 60days with loading of 0.5-1kgVS/m(3)d. Subsequently, the loading to digester was increased step-wise from 2 to 9kgVS/m(3)d. Digester performance was stable at loading between 2 and 6kgVS/m(3)d with an average volatile solid removal and methane yield of 82% and 0.38m(3)/kgVSadded, respectively. However, beyond loading of 7kgVS/m(3)d, solubilization of particulate matter did not take place efficiently. Cyanide present in cassava pulp was successfully degraded indicating that anaerobic sludge in the digester was well acclimatized to cyanide. The results show that cassava pulp can be successfully digested anaerobically with pig manure as co-substrate without any inhibitory effect of cyanide present in the cassava pulp. PMID:27128196

  7. EFFECTS OF INGREDIENTS AND EXTRUSION PARAMETERS ON AQUAFEEDS CONTAINING DDGS AND CASSAVA STARCH

    Science.gov (United States)

    Twenty seven isocaloric (3.05 kcal/g) ingredient blends were factorially formulated using three levels each of DDGS (20, 25, and 30% db), protein (30, 32.5, and 35% db), and feed moisture content (25, 35, and 45% db), along with appropriate quantities of cassava starch, soybean meal, fish meal, whey...

  8. Identification of rapid markers linked to pubescent trait in cassava (manihot esculenta crantz)

    International Nuclear Information System (INIS)

    The presence of pubescence on the leaves of cassava confers resistance to mealybug, an important pest of cassava in Africa. We therefore, investigated RAPD markers linked to the pubescent trait in four descendants of cassava clones TMS 4(2) 1425, namely, diploid (2X) 4(2)1425 pubescent, diploid (2X) 4(2)1425 non-pubescent, tetraploid (4X) 4(2)1425 pubescent, diploid (2X) 4(2)1425 non pubescent as well as forty-eight F1 plants obtained from crossing diploid pubescent and diploid non-pubescent lines. Segments of the extracted DNAs were amplified under standard amplification conditions using Operon primer series A, B, and C making a total of 60 primers. Most primers produced monomorphic fragments. However, two primers, OPA 13 and OPC 19 produced 798bp and 752 bp polymorphic fragments respectively. These were present in non-pubescent but absent in pubescent clones. The 48 F1 hybrids segregated for these markers in a ratio close to 1:1. The markers 798bp-OPA13 and 752bp-OPC19 may be useful for distinguishing between pubescent and non-pubescent cassava clones. (au)

  9. Artificial microRNA-derived resistance to Cassava brown streak disease.

    Science.gov (United States)

    Wagaba, Henry; Patil, Basavaprabhu L; Mukasa, Settumba; Alicai, Titus; Fauquet, Claude M; Taylor, Nigel J

    2016-05-01

    Artificial miRNAs (amiRNA) were generated targeting conserved sequences within the genomes of the two causal agents of Cassava brown streak disease (CBSD): Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV). Transient expression studies on ten amiRNAs targeting 21nt conserved sequences of P1(CBSV and UCBSV), P3(CBSV and UCBSV), CI(UCBSV), NIb(CBSV and UCBSV), CP(UCBSV) and the un-translated region (3'-UTR) were tested in Nicotiana benthamiana. Four out of the ten amiRNAs expressed the corresponding amiRNA at high levels. Transgenic N. benthamiana plants were developed for the four amiRNAs targeting the P1 and NIb genes of CBSV and the P1 and CP genes of UCBSV and shown to accumulate miRNA products. Transgenic plants challenged with CBSV and UCBSV isolates showed resistance levels that ranged between ∼20-60% against CBSV and UCBSV and correlated with expression levels of the transgenically derived miRNAs. MicroRNAs targeting P1 and NIb of CBSV showed protection against CBSV and UCBSV, while amiRNAs targeting the P1 and CP of UCBSV showed protection against UCBSV but were less efficient against CBSV. These results indicate a potential application of amiRNAs for engineering resistance to CBSD-causing viruses in cassava. PMID:26912232

  10. Technical and Socioeconomic Potential of Biogas from Cassava Waste in Ghana.

    Science.gov (United States)

    Kemausuor, Francis; Addo, Ahmad; Darkwah, Lawrence

    2015-01-01

    This study analyses technical potential and ex ante socioeconomic impacts of biogas production using cassava waste from agroprocessing plants. An analysis was performed for two biodigesters in two cassava processing communities in Ghana. The results showed that the two communities generate an excess of 4,500 tonnes of cassava peels per year. Using approximately 5% of the peels generated and livestock manure as inoculum can generate approximately 75,000 m(3) of gas with an estimated 60% methane content from two separate plants of capacities 500 m(3) and 300 m(3) in the two communities. If used internally as process fuel, the potential gas available could replace over 300 tonnes of firewood per year for cassava processing. The displacement of firewood with gas could have environmental, economic, and social benefits in creating sustainable development. With a 10 percent discount rate, an assumed 20-year biodigester will have a Net Present Value of approximately US$ 148,000, 7-year Payback Period, and an Internal Rate of Return of 18.7%. The project will create 10 full-time unskilled labour positions during the investment year and 4 positions during operation years.

  11. Genome-wide association mapping of provitamin A carotenoid content in cassava

    Science.gov (United States)

    Global efforts are underway to develop staple crops with improved levels of provitamin A carotenoids to help combat dietary vitamin A deficiency, which is widespread among resource-poor farmers in the developing world. As a staple crop for more than 500 million people in sub-Saharan Africa, cassava ...

  12. Efficient transmission of Cassava brown streak disease viral pathogens by chip bud grafting

    Science.gov (United States)

    2013-01-01

    Background Techniques to study plant viral diseases under controlled growth conditions are required to fully understand their biology and investigate host resistance. Cassava brown streak disease (CBSD) presents a major threat to cassava production in East Africa. No infectious clones of the causal viruses, Cassava brown streak virus (CBSV) or Ugandan cassava brown streak virus (UCBSV) are available, and mechanical transmission to cassava is not effective. An improved method for transmission of the viruses, both singly and as co-infections has been developed using bud grafts. Findings Axillary buds from CBSD symptomatic plants infected with virulent isolates of CBSV and UCBSV were excised and grafted onto 6–8 week old greenhouse-grown, disease-free cassava plants of cultivars Ebwanateraka, TME204 and 60444. Plants were assessed visually for development of CBSD symptoms and by RT-PCR for presence of the viruses in leaf and storage root tissues. Across replicated experiments, 70-100% of plants inoculated with CBSV developed CBSD leaf and stem symptoms 2–6 weeks after bud grafting. Infected plants showed typical, severe necrotic lesions in storage roots at harvest 12–14 weeks after graft inoculation. Sequential grafting of buds from plants infected with UCBSV followed 10–14 days later by buds carrying CBSV, onto the same test plant, resulted in 100% of the rootstocks becoming co-infected with both pathogens. This dual transmission rate was greater than that achieved by simultaneous grafting with UCBSV and CBSV (67%), or when grafting first with CBSV followed by UCBSV (17%). Conclusions The bud grafting method described presents an improved tool for screening cassava germplasm for resistance to CBSD causal viruses, and for studying pathogenicity of this important disease. Bud grafting provides new opportunities compared to previously reported top and side grafting systems. Test plants can be inoculated as young, uniform plants of a size easily handled in a

  13. Limitations of Cassava Bacterial Blight: New Advances Limitaciones de la bacteriosis vascular de yuca: Nuevos avances

    Directory of Open Access Journals (Sweden)

    Verdier Valérie

    2006-12-01

    Full Text Available Cassava (Manihot esculenta, a starchy root crop, constitutes the source of alimentation for over 600 million people worldwide. Cassava Bacterial Blight (CBB is caused bythe bacterium Xanthomonas axonopodis pv. manihotis (Xam. This review will focus on the current knowledge on the molecular cassava-Xam interaction. We will present the different molecular techniques developed to assess the genetic diversity and dynamics of Xam populations. We will also present different methods developed for detecting the pathogen in vegetative planting materials and true seeds and their contribution to reduce the impact of the disease. We will review different studies conducted to gain a better understanding on the molecular mechanisms and the genes involved in the cassava bacterial resistance, including the recent advances obtained using functional
    genomics. The acquired knowledge in the last years for this pathosystem will help to establish better disease control strategies and generate, in a short term, resistant cassava varieties contributing to solve one of the main problems of poor cassava farmers and this effort will open a new horizon to the cassava crop in the world.La yuca (Manihot esculenta constituye la base de la alimentación de más de 600 millones de personas en el mundo. Una de las principales limitaciones de este cultivo es la bacteriosis vascular, ocasionada por la bacteria Xanthomonas axonopodis pv. manihotis (Xam. Este artículo revisa el conocimiento actual acerca de la interacción Xanthomonas-yuca. Se presentan estudios recientes llevados a cabo sobre la diversidad y dinámica de las poblaciones de Xam empleando diferentes estrategias moleculares. Se describen los diferentes métodos desarrollados para la detección y diagnóstico de la bacteria en plantas y semillas de yuca y su contribución para reducir el impacto de la enfermedad. Se presentan los estudios encaminados a comprender los mecanismos moleculares y los genes

  14. LIMITACIONES DE LA BACTERIOSIS VASCULAR DE YUCA: NUEVOS AVANCES Limitations of Cassava Bacterial Blight: New Advances

    Directory of Open Access Journals (Sweden)

    CAMILO LÓPEZ

    Full Text Available La yuca (Manihot esculenta constituye la base de la alimentación de más de 600 millones de personas en el mundo. Una de las principales limitaciones de este cultivo es la bacteriosis vascular, ocasionada por la bacteria Xanthomonas axonopodis pv. manihotis (Xam. Este artículo revisa el conocimiento actual acerca de la interacción Xanthomonasyuca. Se presentan estudios recientes llevados a cabo sobre la diversidad y dinámica de las poblaciones de Xam empleando diferentes estrategias moleculares. Se describen los diferentes métodos desarrollados para la detección y diagnóstico de la bacteria en plantas y semillas de yuca y su contribución para reducir el impacto de la enfermedad. Se presentan los estudios encaminados a comprender los mecanismos moleculares y los genes responsables en la resistencia de la yuca a la bacteriosis vascular incluyendo los últimos avances obtenidos gracias a la aplicación de estrategias de genómica funcional. El conocimiento adquirido en los últimos años en este patosistema permitirá desarrollar mejores estrategias para el manejo de la enfermedad así como desarrollar a corto plazo variedades de yuca resistentes a la bacteriosis lo que contribuiría a resolver uno de los principales problemas de los productores pobres de yuca y le abriría un horizonte promisorio al cultivo de la yuca en el mundo.Cassava (Manihot esculenta, a starchy root crop, constitutes the source of alimentation for over 600 million people worldwide. Cassava Bacterial Blight (CBB is caused the bacterium Xanthomonas axonopodis pv. manihotis (Xam. This review will focus on the current knowledge on the molecular cassava-Xam interaction. We will present the different molecular techniques developed to assess the genetic diversity and dynamics of Xam populations. We will also present different methods developed for detecting the pathogen in vegetative planting materials and true seeds and their contribution to reduce the impact of the

  15. Elaboration of gluten free cupcakes from xanthosoma flours, taro, rice, cassava and their mixtures

    International Nuclear Information System (INIS)

    The effect of taro flour, xanthosoma, cassava and rice, their possible mixtures and two different percentages of egg protein in cupcakes with total substitution of wheat flour are studied. Flours of xanthosoma and taro were elaborated and have utilized flours of cassava and rice existing in market. The moisture was evaluated and found that taro flour presents a lower water content compared to rice flour, xanthosoma and cassava in all flours. 22 formulations of cupcakes were elaborated using the flours (100% substitutions), flour mixture (substitution 50:50 of each flour) and wheat as control, also the egg content (standard content to egg and lower content to egg), to analyze their sensory characteristics and consumer preferences. The study data was carried out with two independents groups of people, a trained panel that has conducted the descriptive analysis and a consumer group that has made the study of acceptance. An analysis of variance was applied to data, test Fisher LSD and external preference mapping, an analysis of ''cluster '' for proof of acceptance, with witch were identified the three consumer groups, composed by 19, 51, 35 people. All three groups have preferred the control samples with wheat in groups 2 and 3 cupcakes with rice-cassava with content standard and less content of egg, and cassava with less egg, have showed without significant differences in preference (p<0,0001). The group 1 has preferred to wheat samples, taro-cassava with the two egg protein contents, xanthosoma-rice, rice-cassava and xanthosoma with less egg content. An external preferred mapping was made in order to understand which characteristics of each type of cupcake have liked to consumers. The cupcakes with greater acceptance by the segments was observed that were cassava and mixtures with cassava, which have been more spongy, yellow or beige in the crumb and sweet flavor. The taro cupcakes with substitution 100%, blends and samples 100% rice have had less acceptance because

  16. The effects of short-term feeding of fresh cassava (Manihot esculenta) foliage on gastrointestinal nematode parasite infections in goats in Cambodia.

    Science.gov (United States)

    Seng, Sokerya; Waller, Peter J; Ledin, Inger; Höglund, Johan

    2007-06-01

    The antiparasitic effect of cassava (Manihot esculenta Crantz) was tested in goats artificially infected with gastrointestinal parasitic nematodes. Each experimental group consisted of 6 pen-fed goats kept on a slatted floor. The treatments compared were: 1) controls fed grass only, 2) cassava replaced grass for 3 weeks from the commencement of larval dosing period, and 3) cassava replaced grass for 3 weeks after the worm infection was patent. A total of 2000 mixed-species infective nematode larvae (L3) were administered to each goat in four doses of 500 L3/day, commencing 5 weeks after removal of previously acquired infections with ivermectin. The faecal egg counts (FEC) reduced in both cassava fed groups during the time of feeding, compared to the controls. Although, FEC increased differently with time (P cassava in the diet, they do suggest that feeding, or supplementation, of cassava over an extended period may prove beneficial.

  17. Thermal characterization of partially hydrolyzed cassava (Manihot esculenta starch granules

    Directory of Open Access Journals (Sweden)

    Luiz Gustavo Lacerda

    2008-12-01

    Full Text Available Cassava starch, partially hydrolyzed by fungal á-amylase, was characterized using thermal analysis, light microscopy and X-ray diffraction. Thermal degradation was initiated at lower degradation temperatures after enzymatic treatment and the DSC (Differential scanning calorimetry analysis showed almost similar range of gelatinization temperature, but the enthalpies of gelatinization were quite increased for the partially hydrolyzed starch granules. The results suggested that the partial degradation of the starch granules was concentrated in the amorphous regions.Amilases fúngicas são comumente empregadas a amidos com o intuito de otimizar o rendimento de leveduras, modificar a textura de produtos panificados e prolongar a vida de prateleira do produto final. A hidrólise parcial enzimática pode auxiliar no entendimento da estrutura do amido ganular. Amido de mandioca parcialmente hidrolisado por á-amilase fúngica foi investigado utilizando-se técnicas termoanalíticas, microscopia ótica e difratometria por raios X. A degradação térmica iniciou-se a temperaturas menores após o tratamento enzimático e a análise por DSC mostrou uma próxima faixa de temperatura de gelatinização, porém, a entalpia necessária para o evento foi maior para os grânulos parcialmente hidrolisados. Os resultados sugerem que a degradação parcial do amido granular foi concentrada em regiões amorfas.

  18. Fusarium species from the cassava root rot complex in west Africa.

    Science.gov (United States)

    Bandyopadhyay, Ranajit; Mwangi, Maina; Aigbe, Sylvester O; Leslie, John F

    2006-06-01

    ABSTRACT Fusarium species are a significant component of the set of fungi associated with cassava root rot. Yield losses due to root rot average 0.5 to 1 ton/ha but losses >3 ton/ha, an equivalent of 15 to 20% yield, often occur. This paper reviews previous work on cassava root rot and summarizes a few recent studies on Fusarium species associated with the disease. Our studies in Cameroon showed that 30% of rotted tubers were infected by Fusarium spp. 12 months after planting and represented 25% of all the fungal isolates recovered. Other commonly recovered fungi were Botryodiplodia theobromae and Armillaria spp. Numerous and diverse species of Fusarium were associated with rotted cassava roots in Nigeria and Cameroon. At least 13 distinct amplified fragment length polymorphism (AFLP) groups of Fusarium were distinguishable, each group probably a distinct species, and many of them might represent previously undescribed Fusarium species. The two largest of the AFLP groups correspond to F. oxysporum and F. solani species complex. The distribution of Fusarium spp. varied among countries and among locations within a country, suggesting that germ plasm resistant at one location may not be resistant at another. Fusarium spp. also cause seedling blight of cassava and can be recovered from the stems of infected plants up to 1 m above the ground. Therefore, the pathogen can spread with stems cut as planting material. Fusarium spp. also can colonize Chromolaena odorata, the dominant weed in short fallows, which could further complicate management efforts by serving as an alternative host for strains that colonize cassava. PMID:18943189

  19. Loss of CMD2-mediated resistance to cassava mosaic disease in plants regenerated through somatic embryogenesis.

    Science.gov (United States)

    Beyene, Getu; Chauhan, Raj Deepika; Wagaba, Henry; Moll, Theodore; Alicai, Titus; Miano, Douglas; Carrington, James C; Taylor, Nigel J

    2016-09-01

    Cassava mosaic disease (CMD) and cassava brown streak disease (CBSD) are the two most important viral diseases affecting cassava production in Africa. Three sources of resistance are employed to combat CMD: polygenic recessive resistance, termed CMD1, the dominant monogenic type, named CMD2, and the recently characterized CMD3. The farmer-preferred cultivar TME 204 carries inherent resistance to CMD mediated by CMD2, but is highly susceptible to CBSD. Selected plants of TME 204 produced for RNA interference (RNAi)-mediated resistance to CBSD were regenerated via somatic embryogenesis and tested in confined field trials in East Africa. Although micropropagated, wild-type TME 204 plants exhibited the expected levels of resistance, all plants regenerated via somatic embryogenesis were found to be highly susceptible to CMD. Glasshouse studies using infectious clones of East African cassava mosaic virus conclusively demonstrated that the process of somatic embryogenesis used to regenerate cassava caused the resulting plants to become susceptible to CMD. This phenomenon could be replicated in the two additional CMD2-type varieties TME 3 and TME 7, but the CMD1-type cultivar TMS 30572 and the CMD3-type cultivar TMS 98/0505 maintained resistance to CMD after passage through somatic embryogenesis. Data are presented to define the specific tissue culture step at which the loss of CMD resistance occurs and to show that the loss of CMD2-mediated resistance is maintained across vegetative generations. These findings reveal new aspects of the widely used technique of somatic embryogenesis, and the stability of field-level resistance in CMD2-type cultivars presently grown by farmers in East Africa, where CMD pressure is high. PMID:26662210

  20. Influence of cassava genotype and composite flours’ substitution level on rheological behaviour during bread-making

    Directory of Open Access Journals (Sweden)

    Sergio Henao Osorio

    2010-05-01

    Full Text Available Given increasing dependence on imported wheat, studies have been carried out in Colombia regarding the use of composite wheat-cassava flour in bread-making. A project was carried out from 1986-1991 in which different cassava genotypes, harvest ages, substitution levels and bread acceptability were evaluated. However, these studies did not have any effect on the baking sector because a constant supply of high quality, high volume and reasonably-priced cassava flour was lacking. Based on these studies, this work was aimed at determining the influence of three industrial cassava market genotypes (CMC-40, HMC-1, MCOL-1505, using four wheat-cassava flour composite substitution levels (0%, 5%, 10%, 15% regarding the rheological and fermentative characteristics of dough in bread-making. Farinogram, alveogram, amylogram and falling number index analysis were analysed. Specific volume and acceptability of three types of bread (common, mold and hamburger were evaluated. It was determined that composite flours had higher fiber and reduced sugar content than the wheat flour pattern, thereby increasing wa-ter absorption and available sugar content during fermentation. Dough development time for the composite flours was half the a-verage required for wheat flour and the tolerance index was higher; its stability became reduced due to increased substitution le-vels and its firmness increased due to a rise in water absorption. Falling number values came within an acceptable range (250-400 s. The specific volume of all bread having 5% and 10% substitution was higher than that for the pattern. The best general acceptability was assigned to common and mold type bread from all varieties and substitution levels.

  1. Interactive effects of temperature and drought on cassava growth and toxicity: implications for food security?

    Science.gov (United States)

    Brown, Alicia L; Cavagnaro, Timothy R; Gleadow, Ros; Miller, Rebecca E

    2016-10-01

    Cassava is an important dietary component for over 1 billion people, and its ability to yield under drought has led to it being promoted as an important crop for food security under climate change. Despite its known photosynthetic plasticity in response to temperature, little is known about how temperature affects plant toxicity or about interactions between temperature and drought, which is important because cassava tissues contain high levels of toxic cyanogenic glucosides, a major health and food safety concern. In a controlled glasshouse experiment, plants were grown at 2 daytime temperatures (23 °C and 34 °C), and either well-watered or subject to a 1 month drought prior to harvest at 6 months. The objective was to determine the separate and interactive effects of temperature and drought on growth and toxicity. Both temperature and drought affected cassava physiology and chemistry. While temperature alone drove differences in plant height and above-ground biomass, drought and temperature × drought interactions most affected tuber yield, as well as foliar and tuber chemistry, including C : N, nitrogen and cyanide potential (CNp; total cyanide released from cyanogenic glucosides). Conditions that most stimulated growth and yield (well-watered × high temperature) effected a reduction in tuber toxicity, whereas drought inhibited growth and yield, and was associated with increased foliar and tuber toxicity. The magnitude of drought effects on tuber yield and toxicity were greater at high temperature; thus, increases in tuber CNp were not merely a consequence of reduced tuber biomass. Findings confirm that cassava is adaptable to forecast temperature increases, particularly in areas of adequate or increasing rainfall; however, in regions forecast for increased incidence of drought, the effects of drought on both food quality (tuber toxicity) and yield are a greater threat to future food security and indicate an increasing necessity for processing of

  2. Interactive effects of temperature and drought on cassava growth and toxicity: implications for food security?

    Science.gov (United States)

    Brown, Alicia L; Cavagnaro, Timothy R; Gleadow, Ros; Miller, Rebecca E

    2016-10-01

    Cassava is an important dietary component for over 1 billion people, and its ability to yield under drought has led to it being promoted as an important crop for food security under climate change. Despite its known photosynthetic plasticity in response to temperature, little is known about how temperature affects plant toxicity or about interactions between temperature and drought, which is important because cassava tissues contain high levels of toxic cyanogenic glucosides, a major health and food safety concern. In a controlled glasshouse experiment, plants were grown at 2 daytime temperatures (23 °C and 34 °C), and either well-watered or subject to a 1 month drought prior to harvest at 6 months. The objective was to determine the separate and interactive effects of temperature and drought on growth and toxicity. Both temperature and drought affected cassava physiology and chemistry. While temperature alone drove differences in plant height and above-ground biomass, drought and temperature × drought interactions most affected tuber yield, as well as foliar and tuber chemistry, including C : N, nitrogen and cyanide potential (CNp; total cyanide released from cyanogenic glucosides). Conditions that most stimulated growth and yield (well-watered × high temperature) effected a reduction in tuber toxicity, whereas drought inhibited growth and yield, and was associated with increased foliar and tuber toxicity. The magnitude of drought effects on tuber yield and toxicity were greater at high temperature; thus, increases in tuber CNp were not merely a consequence of reduced tuber biomass. Findings confirm that cassava is adaptable to forecast temperature increases, particularly in areas of adequate or increasing rainfall; however, in regions forecast for increased incidence of drought, the effects of drought on both food quality (tuber toxicity) and yield are a greater threat to future food security and indicate an increasing necessity for processing of

  3. Cassava as a non-conventional filler in comminuted meat products.

    Science.gov (United States)

    Annor-Frempong, I E; Annan-Prah, A; Wiredu, R

    1996-11-01

    Cassava (Manihot esculenta) was used as an unconventional filler to produce affordable comminuted meat products that stored well under tropical conditions without refrigeration. The study involved two experiments. In experiment 1, five different emulsion-type pork sausages containing 5.4, 9.0 and 10.0% mould-free cassava flour, 5.4% crude full fat soy flour and a control without filler were assessed 0 and 7 days after preparation. A 40-member taste panel sensorily assessed the products in a 5 × 2 factorial (treatment × storage occasion) experiment based on the external appearance of the uncooked products and the external and internal colour, consistency, texture, aroma and taste of the cooked products. Although the panel judged products with 5.4% cassava flour as the best, the 9% inclusion level of cassava flour was found not to compromise the organoleptic qualities of the product. At this level 54 000 cedis (US$150) was saved on the cost of producing 1t of the product. In experiment 2, the sausages were pasteurised at 80 °C for 1 h and stored in a 4:1 vinegar-sugar solution or a 1:1:50 vinegar-sugar-water solution at 5 and 30 °C. Storage in 4:1 vinegar-sugar medium arrested bacterial growth over the 7-day monitoring period. It was concluded that 9% cassava flour could conveniently replace fat in comminuted meat products and a combination of pasteurisation and storage in vinegar-sugar solution is an effective method of storage of such products in the tropics. PMID:22060829

  4. Current knowledge and future research perspectives on cassava (Manihot esculenta Crantz) chemical defenses: An agroecological view.

    Science.gov (United States)

    Pinto-Zevallos, Delia M; Pareja, Martín; Ambrogi, Bianca G

    2016-10-01

    Cassava (Manihot esculenta Crantz) is one of the most important staple crops worldwide. It constitutes the major source of carbohydrates for millions of low-income people living in rural areas, as well as a cash crop for smallholders in tropical and sub-tropical regions. The Food and Agriculture Organization of the United Nations predicts that cassava plantations will increase and production systems will intensify in the future, highlighting the need for developing strategies that improve the sustainability of production. Plant chemical defenses hold the potential for developing pest management strategies, as these plant traits can influence the behavior and performance of both pests and beneficial arthropods. Cassava plants are well-defended and produce a number of compounds involved in direct defense, such as cyanogenic glycosides, flavonoid glycosides, and hydroxycoumarins. In addition, volatile organic compounds induced upon herbivory and the secretion of extrafloral nectar act as indirect defense against herbivores by recruiting natural enemies. Here, cassava chemical defenses against pest arthropods are reviewed, with the aim of identifying gaps in our knowledge and areas of research that deserve further investigation for developing sound pest control strategies to improve sustainable production of this crop, and how these defenses can be used to benefit other crops. Cyanogenic content in cassava is also highly toxic to humans, and can cause irreversible health problems even at sub-lethal doses when consumed over prolonged periods. Therefore, the promotion of chemical defense in this crop should not aggravate these problems, and must be accompanied with the education on processing methods that reduce human exposure to cyanide. PMID:27316676

  5. Phenolics, Flavonoids, Antioxidant Activity and Cyanogenic Glycosides of Organic and Mineral-base Fertilized Cassava Tubers

    Directory of Open Access Journals (Sweden)

    Puteri Edaroyati Megat Wahab

    2012-02-01

    Full Text Available A field study was conducted to determine the effect of organic and mineral-based fertilizers on phytochemical contents in the tubers of two cassava varieties. Treatments were arranged in a split plot design with three replicates. The main plot was fertilizer source (vermicompost, empty fruit bunch compost and inorganic fertilizer and sub-plot was cassava variety (Medan and Sri Pontian. The amount of fertilizer applied was based on 180 kg K2O ha−1. The tubers were harvested and analyzed for total flavonoids, total phenolics, antioxidant activity and cyanogenic glucoside content. Total phenolic and flavonoid compounds were determined using the Folin-Ciocalteu assay and aluminium chloride colorimetric method, respectively. Different sources of fertilizer, varieties and their interactions were found to have a significant effect on phytochemical content. The phenolic and flavonoid content were significantly higher (p < 0.01 in the vermicompost treatment compared to mineral fertilizer and EFB compost. The total flavonoids and phenolics content of vermicompost treated plants were 39% and 38% higher, respectively, than those chemically fertilized. The antioxidant activity determined using the DPPH and FRAP assays were high with application of organic fertilizer. Cyanogenic glycoside levels were decreased with the application of organic fertilizer. Among the two types of compost, vermicompost resulted in higher nutritional value of cassava tubers. Medan variety with application of vermicompost showed the most promising nutritional quality. Since the nutritional quality of cassava can be improved by organic fertilization, organic fertilizer should be used in place of chemical fertilizer for environmentally sustainable production of better quality cassava.

  6. Cassava Peels for Alternative Fibre in Pulp and Paper Industry: Chemical Properties and Morphology Characterization

    Directory of Open Access Journals (Sweden)

    Ashuvila Mohd Aripin

    2013-11-01

    Full Text Available Without a proper waste management, the organic wastes such as cassava peels could result in increased amount of solid waste dump into landfill. This study aims to use non-wood organic wastes as pulp for paper making industries; promoting the concept of ‘from waste to wealth and recyclable material’. The objective  of this study is to determine the potential of casssava peel as alternative fibre in pulp and paper based on its chemical properties and surface morphology characteristic. Quantified parameters involved are holocellulose, cellulose, hemicellulose, lignin, one percent of sodium hydroxide, hot water solubility and ash content. The chemical characterization was in accordance with relevant TAPPI Test, Kurscher-Hoffner and Chlorite methods. Scanning electron microscopy (SEM was used to observe and determine the morphological characteristic of untreated cassava peels fibre. In order to propose the suitability of the studied plant as an alternative fibre resource in pulp and paper making, the obtained results are compared to other published literatures especially from wood sources. Results indicated that the amount of holocellulose contents in cassava peels (66% is the lowest than of wood (70 - 80.5% and canola straw (77.5%; however this value is still within the limit suitability to produce paper. The lignin content (7.52% is the lowest than those of all wood species (19.9-26.22%. Finally, the SEM images showed that untreated cassava peel contains abundance fibre such as hemicellulose and cellulose that is hold by the lignin in it. In conclusion, chemical properties and morphological characteristics of cassava peel indicated that it is suitable to be used as an alternative fibre sources for pulp and paper making industry, especially in countries with limited wood resources

  7. An ordered EST catalogue and gene expression profiles of cassava (Manihot esculenta) at key growth stages.

    Science.gov (United States)

    Li, You-Zhi; Pan, Ying-Hua; Sun, Chang-Bin; Dong, Hai-Tao; Luo, Xing-Lu; Wang, Zhi-Qiang; Tang, Ji-Liang; Chen, Baoshan

    2010-12-01

    A cDNA library was constructed from the root tissues of cassava variety Huanan 124 at the root bulking stage. A total of 9,600 cDNA clones from the library were sequenced with single-pass from the 5'-terminus to establish a catalogue of expressed sequence tags (ESTs). Assembly of the resulting EST sequences resulted in 2,878 putative unigenes. Blastn analysis showed that 62.6% of the unigenes matched with known cassava ESTs and the rest had no 'hits' against the cassava database in the integrative PlantGDB database. Blastx analysis showed that 1,715 (59.59%) of the unigenes matched with one or more GenBank protein entries and 1,163 (40.41%) had no 'hits'. A cDNA microarray with 2,878 unigenes was developed and used to analyze gene expression profiling of Huanan 124 at key growth stages including seedling, formation of root system, root bulking, and starch maturity. Array data analysis revealed that (1) the higher ratio of up-regulated ribosome-related genes was accompanied by a high ratio of up-regulated ubiquitin, proteasome-related and protease genes in cassava roots; (2) starch formation and degradation simultaneously occur at the early stages of root development but starch degradation is declined partially due to decrease in UDP-glucose dehydrogenase activity with root maturity; (3) starch may also be synthesized in situ in roots; (4) starch synthesis, translocation, and accumulation are also associated probably with signaling pathways that parallel Wnt, LAM, TCS and ErbB signaling pathways in animals; (5) constitutive expression of stress-responsive genes may be due to the adaptation of cassava to harsh environments during long-term evolution.

  8. Growth and nutritive value of cassava (Manihot esculenta Cranz.) are reduced when grown in elevated CO.

    Science.gov (United States)

    Gleadow, Roslyn M; Evans, John R; McCaffery, Stephanie; Cavagnaro, Timothy R

    2009-11-01

    Global food security in a changing climate depends on both the nutritive value of staple crops as well as their yields. Here, we examined the direct effect of atmospheric CO(2) on cassava (Manihot esculenta Cranz., manioc), a staple for 750 million people worldwide. Cassava is poor in nutrients and contains high levels of cyanogenic glycosides that break down to release toxic hydrogen cyanide when damaged. We grew cassava at three concentrations of CO(2) (C(a): 360, 550 and 710 ppm) supplied together with nutrient solution containing either 1 mM or 12 mM nitrogen. We found that total plant biomass and tuber yield (number and mass) decreased linearly with increasing C(a). In the worst-case scenario, tuber mass was reduced by an order of magnitude in plants grown at 710 ppm compared with 360 ppm CO(2). Photosynthetic parameters were consistent with the whole plant biomass data. It is proposed that since cassava stomata are highly sensitive to other environmental variables, the decrease in assimilation observed here might, in part, be a direct effect of CO(2) on stomata. Total N (used here as a proxy for protein content) and cyanogenic glycoside concentrations of the tubers were not significantly different in the plants grown at elevated CO(2). By contrast, the concentration of cyanogenic glycosides in the edible leaves nearly doubled in the highest C(a). If leaves continue to be used as a protein supplement, they will need to be more thoroughly processed in the future. With increasing population density, declining soil fertility, expansion into marginal farmland, together with the predicted increase in extreme climatic events, reliance on robust crops such as cassava will increase. The responses to CO(2) shown here point to the possibility that there could be severe food shortages in the coming decades unless CO(2) emissions are dramatically reduced, or alternative cultivars or crops are developed.

  9. Current knowledge and future research perspectives on cassava (Manihot esculenta Crantz) chemical defenses: An agroecological view.

    Science.gov (United States)

    Pinto-Zevallos, Delia M; Pareja, Martín; Ambrogi, Bianca G

    2016-10-01

    Cassava (Manihot esculenta Crantz) is one of the most important staple crops worldwide. It constitutes the major source of carbohydrates for millions of low-income people living in rural areas, as well as a cash crop for smallholders in tropical and sub-tropical regions. The Food and Agriculture Organization of the United Nations predicts that cassava plantations will increase and production systems will intensify in the future, highlighting the need for developing strategies that improve the sustainability of production. Plant chemical defenses hold the potential for developing pest management strategies, as these plant traits can influence the behavior and performance of both pests and beneficial arthropods. Cassava plants are well-defended and produce a number of compounds involved in direct defense, such as cyanogenic glycosides, flavonoid glycosides, and hydroxycoumarins. In addition, volatile organic compounds induced upon herbivory and the secretion of extrafloral nectar act as indirect defense against herbivores by recruiting natural enemies. Here, cassava chemical defenses against pest arthropods are reviewed, with the aim of identifying gaps in our knowledge and areas of research that deserve further investigation for developing sound pest control strategies to improve sustainable production of this crop, and how these defenses can be used to benefit other crops. Cyanogenic content in cassava is also highly toxic to humans, and can cause irreversible health problems even at sub-lethal doses when consumed over prolonged periods. Therefore, the promotion of chemical defense in this crop should not aggravate these problems, and must be accompanied with the education on processing methods that reduce human exposure to cyanide.

  10. Variation in cassava germplasm for tolerance to post-harvest physiological deterioration.

    Science.gov (United States)

    Venturini, M T; Santos, L R; Vildoso, C I A; Santos, V S; Oliveira, E J

    2016-01-01

    Tolerant varieties can effectively control post-harvest physiological deterioration (PPD) of cassava, although knowledge on the genetic variability and inheritance of this trait is needed. The objective of this study was to estimate genetic parameters and identify sources of tolerance to PPD and their stability in cassava accessions. Roots from 418 cassava accessions, grown in four independent experiments, were evaluated for PPD tolerance 0, 2, 5, and 10 days post-harvest. Data were transformed into area under the PPD-progress curve (AUP-PPD) to quantify tolerance. Genetic parameters, stability (Si), adaptability (Ai), and the joint analysis of stability and adaptability (Zi) were obtained via residual maximum likelihood (REML) and best linear unbiased prediction (BLUP) methods. Variance in the genotype (G) x environment (E) interaction and genotypic variance were important for PPD tolerance. Individual broad-sense heritability (hg(2)= 0.38 ± 0.04) and average heritability in accessions (hmg(2)= 0.52) showed high genetic control of PPD tolerance. Genotypic correlation of AUP-PPD in different experiments was of medium magnitude (ȓgA = 0.42), indicating significant G x E interaction. The predicted genotypic values o f G x E free of interaction (û + ĝi) showed high variation. Of the 30 accessions with high Zi, 19 were common to û + ĝi, Si, and Ai parameters. The genetic gain with selection of these 19 cassava accessions was -55.94, -466.86, -397.72, and -444.03% for û + ĝi, Si, Ai, and Zi, respectively, compared with the overall mean for each parameter. These results demonstrate the variability and potential of cassava germplasm to introduce PPD tolerance in commercial varieties. PMID:27173317

  11. 木薯抗旱机制研究进展%Research Status of the Drought Resistance Mechanism of Cassava

    Institute of Scientific and Technical Information of China (English)

    孟富宣; 刘海刚; 沙毓沧; 段元杰; 杨玉皎; 黄洁

    2015-01-01

    Drought influences the growth and development of cassava seriously. The mechanism and the research status in domestic and overseas on drought resistance and endurance of cassava from three aspects: nutritional organ features, molecular biology and gene expression of drought resistance. Finally, this paper proposed the future research directions and emphasis about drought resistance mechanism of cassava. With the development of correlative researches and advanced technology, Molecular Biotechnology and gene expression will become research focus on the drought resistance mechanism of cassava.%从木薯营养器官特性、生理生化特性、抗旱分子生物学与抗旱基因等3个方面对国内外木薯抗旱和耐旱机制及研究现状进行综述,提出了今后研究木薯抗旱机制的重点和方向。

  12. [Multi-objectives optimization on life cycle pollutants emission of cassava-based ethanol blended gasoline fuels].

    Science.gov (United States)

    Pu, Geng-qiang; Hu, Zhi-yuan; Wang, Cheng-tao

    2004-09-01

    An optimization model on life cycle pollutants emission of cassava-based ethanol blended gasoline fuels, including single and multi-objectives, was carried out in this paper. And, the single and multi-objectives optimization of cassava-based ethanol blended gasoline fuels were done, using the life cycle CO, NOx, PM, HC, SOx, CO2 emissions as objectives. Moreover, sensitivity analysis of design variables was done. The multi-objectives results shown that the blend ratio between cassava-based ethanol and gasoline was 63%. Compare with the initial value, multi-objective optimization of cassava-based ethanol blended gasoline fuels achieved a little more life cycle CO, NOx and PM emissions, about 1%, 15% and 19% respectively, and reduced life cycle HC, SOx and CO2 emissions, 8%, 50%, and 21% respectively.

  13. Analysis of the cost and return to management of small scale cassava production in the humid zone of Nigeria

    Directory of Open Access Journals (Sweden)

    Guobadia, E.

    1993-01-01

    Full Text Available Cassava is a major staple food in Nigeria. Available literature showed that not much work had been done on the return to management (RTM of this crop particularly in recent times. Crop production variables of capital, hired labour, family labour and fertilizer-use were studied. Costs and returns of cassava production in the study area were computed. The study showed that the average cost of producing an hectare of cassava irf N 10, 343.99. The total return was valued at N 45, 165.57 with an average RTM of N 34, 821.58. The study also revealed that labour and fertilizer are crucial variables to productivity of the farm-firm in terms of output per hectare. It was concluded that cassava production is a profitable venture and comparable to any Government Service which the unemployed and young school leavers should be encouraged to go into.

  14. Differentiated Gender Ownership of Cassava Fields and Implications for Root Yield Variations in Small Holder Agriculture of Southeast Nigeria

    Directory of Open Access Journals (Sweden)

    Enete, AA.

    2001-01-01

    Full Text Available As a result of their relatively limited access to production resources, it has been variously reported that women obtain lower yields from their individual crop fields than men. Cassava root yields obtained from farmers' fields in three villages of southeast Nigeria were compared using separate ownership of fields by gender as a factor. The result of the analysis fails to confirm lower yields from women's fields. Instead, mean fresh root yield was lower for fields owned individually by men than for those owned individually by women, and about the same for fields owned jointly by the whole family and those owned individually by women. This was apparently because of differences in the use of purchased inputs, especially hired labor and improved cassava varieties, and perhaps also due to differences in the age of cassava at harvest and the intercropping of cassava as a minor crop with yam.

  15. Comparative Proteome Analysis of the Tuberous Roots of Six Cassava (Manihot esculenta) Varieties Reveals Proteins Related to Phenotypic Traits.

    Science.gov (United States)

    Schmitz, Gabriela Justamante Händel; de Magalhães Andrade, Jonathan; Valle, Teresa Losada; Labate, Carlos Alberto; do Nascimento, João Roberto Oliveira

    2016-04-27

    Cassava (Manihot esculenta Crantz) is a staple food and an important source of starch, and the attributes of its tuberous root largely depend on the variety. The proteome of cassava has been investigated; however, to date, no study has focused on varieties that reveal the molecular basis of phenotypical characteristics. Therefore, we aimed to compare the proteome of the tuberous roots of six cassava varieties that differed in carbohydrates, carotenoids, and resistance to diseases, among other attributes. Two-dimensional gels showed 146 differential spots between the varieties, and the functional roles of some differential proteins were correlated to phenotypic characteristics of the varieties, such as the amount of carbohydrates or carotenoids and the resistance to biotic or abiotic stresses. The results obtained here highlight elements that might help to direct the improvement of new cultivars of cassava, which is an economically and socially relevant crop worldwide.

  16. Comparative Proteome Analysis of the Tuberous Roots of Six Cassava (Manihot esculenta) Varieties Reveals Proteins Related to Phenotypic Traits.

    Science.gov (United States)

    Schmitz, Gabriela Justamante Händel; de Magalhães Andrade, Jonathan; Valle, Teresa Losada; Labate, Carlos Alberto; do Nascimento, João Roberto Oliveira

    2016-04-27

    Cassava (Manihot esculenta Crantz) is a staple food and an important source of starch, and the attributes of its tuberous root largely depend on the variety. The proteome of cassava has been investigated; however, to date, no study has focused on varieties that reveal the molecular basis of phenotypical characteristics. Therefore, we aimed to compare the proteome of the tuberous roots of six cassava varieties that differed in carbohydrates, carotenoids, and resistance to diseases, among other attributes. Two-dimensional gels showed 146 differential spots between the varieties, and the functional roles of some differential proteins were correlated to phenotypic characteristics of the varieties, such as the amount of carbohydrates or carotenoids and the resistance to biotic or abiotic stresses. The results obtained here highlight elements that might help to direct the improvement of new cultivars of cassava, which is an economically and socially relevant crop worldwide. PMID:26982619

  17. Development Trend of Cassava Industry and Market Analysis in China%我国木薯产业的发展趋势与市场分析①

    Institute of Scientific and Technical Information of China (English)

    文玉萍

    2014-01-01

    Expatiating on domestic current progress in cassava planting, cassava starch (modified starch) and cassava alcohol, and prospects of their future development tendency.%对我国的木薯种植,木薯淀粉(变性淀粉),木薯酒精行业的发展现状进行阐述,展望其发展趋势。

  18. Physical characteristics of extruded cassava starch Características físicas de amido de mandioca extrusado

    OpenAIRE

    Magali Leonel; Taila Santos de Freitas; Martha Maria Mischan

    2009-01-01

    Considering the importance of cassava starch for Brazilian industries, the current work aimed at evaluating the effects of extrusion parameters on the physical characteristics, mainly viscosity properties of extruded cassava starch. A factorial central composite design (2³) with three independent variables and the response surface methodology were used to evaluate the results of expansion index, specific volume, water absorption index, water solubility index, color and paste properties, accor...

  19. Effect of the Addition of Catfish Meat on Improving of Jerked Meat Protein from Cassava Leaves (Manihot utilissima)

    OpenAIRE

    Sahadi Didi Ismanto; Surini Siswardjono; Silvia Nengsih

    2015-01-01

    This study aimed to determine the effect of catfish meat to increase protein of jerked meat cassava leaves (Manihot utilissima) and  to find the best products from cassava leaves jerked meat. This research was conducted at the Laboratory of Engineering and Process Technology,  Chemical Agricultural Products and Nutrition Department of Agricultural Technology Andalas University from August to October 2014. The method used in this study experimental method, using a completely randomized design ...

  20. The effect of chemical treatments on the pH & microbial flora of cassava residues during storage

    OpenAIRE

    Thaísa Anders Carvalho Souza; Manoel Soares Júnior; Maria Raquel Hidalgo Campos; Thaynara Stella Carvalho Souza; Lívia Cunha Bandeira

    2013-01-01

    Cassava starch factories produce residues that can be commercialized as food ingredients. The objective of this study was to evaluate the microbiological safety of cassava peel and bagasse during storage, with and without chemical treatment. The bagasse was acidified with lactic acid, and the peel was immersed in a sodium hypochlorite solution. The microbiological analyses were carried out for 72 h after harvest. All of the samples showed the absence of pathogenic microorganisms, and the acid...

  1. Large-Scale SNP Discovery through RNA Sequencing and SNP Genotyping by Targeted Enrichment Sequencing in Cassava (Manihot esculenta Crantz)

    OpenAIRE

    Pootakham, Wirulda; Shearman, Jeremy R.; Ruang-areerate, Panthita; Sonthirod, Chutima; Sangsrakru, Duangjai; Jomchai, Nukoon; Yoocha, Thippawan; Triwitayakorn, Kanokporn; Tragoonrung, Somvong; Tangphatsornruang, Sithichoke

    2014-01-01

    Cassava (Manihot esculenta Crantz) is one of the most important crop species being the main source of dietary energy in several countries. Marker-assisted selection has become an essential tool in plant breeding. Single nucleotide polymorphism (SNP) discovery via transcriptome sequencing is an attractive strategy for genome complexity reduction in organisms with large genomes. We sequenced the transcriptome of 16 cassava accessions using the Illumina HiSeq platform and identified 675,559 EST-...

  2. Interaction Between An Insect Pseudotheraptus devastans dist And A Fungus Colletotrichum gloeosporioides penz On Setting Of Anthracnose On Cassava Cuttings

    Directory of Open Access Journals (Sweden)

    Makambila, C.

    1994-01-01

    Full Text Available Interaction of an insect Pseudotheraptus devastans and of a fungus Colletotrichum gloeosporioides on cassava anthracnose development has been studied. Disease setting is made in two stages : realization of wounds on cassava cuttings by Pseudotheraptus devastans, then invasion of those ones by Colletotrichum gloeosporioides. Infection also needs a high level of relative humidity (87 % and a favourable temperature. Optimal values are situated between 24 and 28°C.

  3. Domestication Syndrome Is Investigated by Proteomic Analysis between Cultivated Cassava (Manihot esculenta Crantz and Its Wild Relatives.

    Directory of Open Access Journals (Sweden)

    Feifei An

    Full Text Available Cassava (Manihot esculenta Crantz wild relatives remain a largely untapped potential for genetic improvement. However, the domestication syndrome phenomena from wild species to cultivated cassava remain poorly understood. The analysis of leaf anatomy and photosynthetic activity showed significantly different between cassava cultivars SC205, SC8 and wild relative M. esculenta ssp. Flabellifolia (W14. The dry matter, starch and amylose contents in the storage roots of cassava cultivars were significantly more than that in wild species. In order to further reveal the differences in photosynthesis and starch accumulation of cultivars and wild species, the globally differential proteins between cassava SC205, SC8 and W14 were analyzed using 2-DE in combination with MALDI-TOF tandem mass spectrometry. A total of 175 and 304 proteins in leaves and storage roots were identified, respectively. Of these, 122 and 127 common proteins in leaves and storage roots were detected in SC205, SC8 and W14, respectively. There were 11, 2 and 2 unique proteins in leaves, as well as 58, 9 and 12 unique proteins in storage roots for W14, SC205 and SC8, respectively, indicating proteomic changes in leaves and storage roots between cultivated cassava and its wild relatives. These proteins and their differential regulation across plants of contrasting leaf morphology, leaf anatomy pattern and photosynthetic related parameters and starch content could contribute to the footprinting of cassava domestication syndrome. We conclude that these global protein data would be of great value to detect the key gene groups related to cassava selection in the domestication syndrome phenomena.

  4. Impact of style of processing on retention and bioaccessibility of beta-carotene in cassava (Manihot esculanta, Crantz).

    Science.gov (United States)

    Thakkar, Sagar K; Huo, Tianyao; Maziya-Dixon, Bussie; Failla, Mark L

    2009-02-25

    We previously demonstrated that the quantity of beta-carotene (BC) partitioning in mixed micelles during simulated small intestinal digestion, i.e., the bioaccessibility, of boiled cassava is highly correlated with the BC content of different cultivars. However, cassava is also traditionally prepared by fermentation and roasting. These different methods of preparation have the potential to affect both the retention and bioaccessibility of BC. Here, we first compared retention of BC in boiled cassava, gari (fermentation followed by roasting), and fufu (fermentation followed by sieving and cooking into a paste) prepared from roots of three cultivars. BC content in unprocessed cultivars ranged from 6-8 microg/g wet weight, with cis isomers accounting for approximately one-third of total BC. Apparent retention of BC was approximately 90% for boiled cassava and fufu. In contrast, roasting fermented cassava at 195 degrees C for 20 min to prepare gari decreased BC content by 90%. Retention was increased to 63% when temperature was decreased to 165 degrees C and roasting was limited to 10 min. Processing was also associated with a decline in all-trans-BC and concomitant increase in 13-cis-BC. The efficiency of micellarization of all-trans and cis isomers of BC during simulated digestion was 25-30% for boiled cassava and gari and independent of cultivar. However, micellarization of BC isomers during digestion of fufu was only 12-15% (P cassava products prepared according to traditional processing methods suggest that gari and fufu may provide less retinol activity equivalents than isocaloric intake of boiled cassava.

  5. Domestication Syndrome Is Investigated by Proteomic Analysis between Cultivated Cassava (Manihot esculenta Crantz) and Its Wild Relatives.

    Science.gov (United States)

    An, Feifei; Chen, Ting; Stéphanie, Djabou Mouafi Astride; Li, Kaimian; Li, Qing X; Carvalho, Luiz J C B; Tomlins, Keith; Li, Jun; Gu, Bi; Chen, Songbi

    2016-01-01

    Cassava (Manihot esculenta Crantz) wild relatives remain a largely untapped potential for genetic improvement. However, the domestication syndrome phenomena from wild species to cultivated cassava remain poorly understood. The analysis of leaf anatomy and photosynthetic activity showed significantly different between cassava cultivars SC205, SC8 and wild relative M. esculenta ssp. Flabellifolia (W14). The dry matter, starch and amylose contents in the storage roots of cassava cultivars were significantly more than that in wild species. In order to further reveal the differences in photosynthesis and starch accumulation of cultivars and wild species, the globally differential proteins between cassava SC205, SC8 and W14 were analyzed using 2-DE in combination with MALDI-TOF tandem mass spectrometry. A total of 175 and 304 proteins in leaves and storage roots were identified, respectively. Of these, 122 and 127 common proteins in leaves and storage roots were detected in SC205, SC8 and W14, respectively. There were 11, 2 and 2 unique proteins in leaves, as well as 58, 9 and 12 unique proteins in storage roots for W14, SC205 and SC8, respectively, indicating proteomic changes in leaves and storage roots between cultivated cassava and its wild relatives. These proteins and their differential regulation across plants of contrasting leaf morphology, leaf anatomy pattern and photosynthetic related parameters and starch content could contribute to the footprinting of cassava domestication syndrome. We conclude that these global protein data would be of great value to detect the key gene groups related to cassava selection in the domestication syndrome phenomena.

  6. Effect of elevated CO2 concentration and nitrate: ammonium ratios on gas exchange and growth of cassava (Manihot esculenta Crantz)

    Science.gov (United States)

    This study evaluated how different nitrogen forms affect growth and photosynthetic responses of cassava to CO2 concentration. Cassava was grown in 12-L pots in a greenhouse (30/25o C day / night) at 390 or 750 ppm of CO2. Three nitrogen treatments were applied: (a) 12 mM NO3-, (b) 6 mM NO3- + 6 mM N...

  7. Biological parameters of Bemisia tabaci (Gennadius) biotype B (Hemiptera: Aleyrodidae) on Jatropha gossypiifolia, commercial (Manihot esculenta) and wild cassava (Manihot flabellifolia and M. carthaginensis) (Euphorbiaceae).

    Science.gov (United States)

    Carabalí, Arturo; Belloti, Anthony C; Montoya-Lerma, James

    2010-01-01

    Bemisia tabaci (Gennadius) is one of the most important pests of cassava in Africa and several countries of Asia due to the damage caused by direct feeding, the excretion of honeydew, and its capacity as a vector of cassava mosaic geminivirus. There is a general consensus that B. tabaci is a complex of morphologically indistinguishable populations with different biotypes. In the Americas, the polyphagous biotype B does not appear to feed on cassava. Recent studies indicate that it is possible, however, for biotype B to gradually adapt to cassava using phylogenetically related hosts. Therefore, the possibility that some wild species of cassava constitute intermediate hosts in the adaptation process may lead to the establishment of biotype B on commercial varieties of Manihot esculenta. In here, we evaluated Jatropha gossypiifolia, two wild species of cassava (Manihot flabellifolia and M. carthaginensis) and a commercial cassava variety (MCol 2063) as hosts of biotype B. The highest oviposition rate (2.7 eggs /two days) occurred on M. esculenta, although the development time (44 d) was the longest when compared to M. carthaginensis and J. gossypiifolia. About 60% of the population could reproduce on the wild cassava species vs. 55% on J. gossypiifolia and 27.5% on the commercial variety. Our data suggest that J. gossypiifolia is a suitable host and the wild species M. carthaginensis can constitute a potential intermediate host in the adaptation of biotype B to commercial varieties of cassava.

  8. The use of blends of cassava flour and extruded full-fat soybeans in diets for broiler chickens.

    Science.gov (United States)

    Waldroup, P W; Ritchie, S J; Reese, G L; Ramsey, B E

    1984-09-01

    A study was conducted to determine the effects of blending different levels of a low-prussic acid cassava flour with extruded full-fat soybeans in diets for growing broiler chickens. The full-fat soybeans contribute oil which increases the energy content of the diet, aids in overcoming the dusty nature of cassava, and provide high-quality protein. One-third, two-thirds, and all of the maize was replaced by cassava in diets with none, 12.5 and 25% extruded full-fat soybeans. Diets were fed in pelleted form to broiler chickens for a 47-day feeding trial. Replacement of one-third of the maize with cassava had no adverse effects on body weight gains in this study with a reduction in weight at higher levels at the conclusion of the study. Feed utilization was reduced more severely than was anticipated. However, growth rate on the higher levels of cassava was reasonably good, indicating that producers might feed these diets for a slightly longer period of time and produce chickens more economically if cassava meal were available at a cost significantly less than that of maize. PMID:6544063

  9. Genome-Wide Identification and Expression Analysis of the Mitogen-Activated Protein Kinase Gene Family in Cassava.

    Science.gov (United States)

    Yan, Yan; Wang, Lianzhe; Ding, Zehong; Tie, Weiwei; Ding, Xupo; Zeng, Changying; Wei, Yunxie; Zhao, Hongliang; Peng, Ming; Hu, Wei

    2016-01-01

    Mitogen-activated protein kinases (MAPKs) play central roles in plant developmental processes, hormone signaling transduction, and responses to abiotic stress. However, no data are currently available about the MAPK family in cassava, an important tropical crop. Herein, 21 MeMAPK genes were identified from cassava. Phylogenetic analysis indicated that MeMAPKs could be classified into four subfamilies. Gene structure analysis demonstrated that the number of introns in MeMAPK genes ranged from 1 to 10, suggesting large variation among cassava MAPK genes. Conserved motif analysis indicated that all MeMAPKs had typical protein kinase domains. Transcriptomic analysis suggested that MeMAPK genes showed differential expression patterns in distinct tissues and in response to drought stress between wild subspecies and cultivated varieties. Interaction networks and co-expression analyses revealed that crucial pathways controlled by MeMAPK networks may be involved in the differential response to drought stress in different accessions of cassava. Expression of nine selected MAPK genes showed that these genes could comprehensively respond to osmotic, salt, cold, oxidative stressors, and abscisic acid (ABA) signaling. These findings yield new insights into the transcriptional control of MAPK gene expression, provide an improved understanding of abiotic stress responses and signaling transduction in cassava, and lead to potential applications in the genetic improvement of cassava cultivars. PMID:27625666

  10. The development of cassava stem returning crushing machine%木薯杆粉碎还田机的研制

    Institute of Scientific and Technical Information of China (English)

    吴锡毅; 关意昭; 周世英; 黄正文; 邵仁清

    2014-01-01

    针对木薯收获的需要,研究开发一款木薯茎杆(以下统称木薯杆)粉碎还田机械。根据木薯杆砍伐、收集、粉碎作业的特点,该机器采用拖拉机前悬挂布置方式,由液压系统传递动力,集合木薯杆砍伐、收集、粉碎功能,是木薯全程机械化种植的重要组成部分。%Aiming at the need of cassava harvest, research and development a cassava stem (hereinafter generally referred to as the cassava stem) returning grinding machine. According to the characteristics of cassava stem deforestation, collection, crushing homework, the machine adopts the tractor front suspension arrangement, by the hydraulic system transfer the power, the collection of cassava stem cutting, collection, crushing function, is an important part of cassava full mechanization planting.

  11. Domestication and defence: Foliar tannins and C/N ratios in cassava and a close wild relative

    Science.gov (United States)

    Mondolot, Laurence; Marlas, Amandine; Barbeau, Damien; Gargadennec, Annick; Pujol, Benoît; McKey, Doyle

    2008-09-01

    Plant domestication is accompanied by shifts in resource allocation, as a result of farmer selection for genotypes that give high yields in agricultural habitats. Relaxed natural selection for chemical and physical defences in these habitats could facilitate resource allocation to yield. We compared the concentrations of tannins, and C/N ratios, which are often correlated with investment in cell-wall compounds, in leaves of landraces of domesticated cassava ( Manihot esculenta) and a close wild relative in French Guiana. Foliar concentrations of tannins were about 1.9 times higher in the wild relative than in domesticated cassava. Histochemical analyses showed that tannins were present in nearly all palisade and spongy parenchyma cells of the wild taxon, but in only some cells of these tissues in M. esculenta. C/N ratios were also 1.9 times higher in leaves of the wild relative than in those of domesticated cassava. Tannins accounted for only a small proportion of total carbon, and the higher C/N ratio in wild than in domesticated cassava may reflect higher investment in carbon-containing compounds additional to tannins, such as cell-wall compounds. The divergence in these traits between cassava and this close wild relative mirrors a broad pattern observed in wild plant species across habitats varying in resource availability. One explanation for our results is that domestication in cassava may have favoured a shift from a resource conservation strategy to a resource acquisition strategy.

  12. Isolation and partial characterization of a root-specific promoter for stacking multiple traits into cassava (Manihot esculenta CRANTZ).

    Science.gov (United States)

    Gbadegesin, M A; Beeching, J R

    2011-06-07

    Cassava can be cultivated on impoverished soils with minimum inputs, and its storage roots are a staple food for millions in Africa. However, these roots are low in bioavailable nutrients and in protein content, contain cyanogenic glycosides, and suffer from a very short post-harvest shelf-life, and the plant is susceptible to viral and bacterial diseases prevalent in Africa. The demand for improvement of cassava with respect to these traits comes from both farmers and national agricultural institutions. Genetic improvement of cassava cultivars by molecular biology techniques requires the availability of appropriate genes, a system to introduce these genes into cassava, and the use of suitable gene promoters. Cassava root-specific promoter for auxin-repressed protein was isolated using the gene walking approach, starting with a cDNA sequence. In silico analysis of promoter sequences revealed putative cis-acting regulatory elements, including root-specific elements, which may be required for gene expression in vascular tissues. Research on the activities of this promoter is continuing, with the development of plant expression cassettes for transformation into major African elite lines and farmers' preferred cassava cultivars to enable testing of tissue-specific expression patterns in the field.

  13. Enhancer/Suppressor mutator (En/Spm)-like transposable elements of cassava (Manihot esculenta) are transcriptionally inactive.

    Science.gov (United States)

    Gbadegesin, M A; Beeching, J R

    2010-04-13

    Transposable elements contribute to the size, structure, variation, and diversity of the genome and have major effects on gene function. Sequencing projects have revealed the diversity of transposable elements in many organisms and have shown that they constitute a high percentage of the genome. PCR-based techniques using degenerate primers designed from conserved enzyme domains of transposable elements can provide quick and extensive surveys, making study of diversity and abundance and their applications possible in species where full genome sequence data are not yet available. We studied cassava (Manihot esculenta) En/Spm-like transposons (Meens) with regard to genomic distribution, sequence diversity and methylation status. Cassava transposase fragments characteristic of En/Spm-like transposons were isolated, cloned and characterized. Sequence analysis showed that cassava En/Spm-like elements are highly conserved, with overall identity in the range of 68-98%. Southern hybridization supports the presence of multiple copies of En/Spm-like transposons integrated in the genome of all cassava cultivars that we tested. Hybridization patterns of HpaII- and MspI-digested cassava genomic DNA revealed highly methylated sequences. There were no clear differences in hybridization pattern between the cultivars. We did not detect RNA transcripts of Meens by Northern procedures. We examined the possibility of recent transposition activities of the cassava En/Spm-like elements.

  14. Genome-Wide Identification and Expression Analysis of the Mitogen-Activated Protein Kinase Gene Family in Cassava

    Science.gov (United States)

    Yan, Yan; Wang, Lianzhe; Ding, Zehong; Tie, Weiwei; Ding, Xupo; Zeng, Changying; Wei, Yunxie; Zhao, Hongliang; Peng, Ming; Hu, Wei

    2016-01-01

    Mitogen-activated protein kinases (MAPKs) play central roles in plant developmental processes, hormone signaling transduction, and responses to abiotic stress. However, no data are currently available about the MAPK family in cassava, an important tropical crop. Herein, 21 MeMAPK genes were identified from cassava. Phylogenetic analysis indicated that MeMAPKs could be classified into four subfamilies. Gene structure analysis demonstrated that the number of introns in MeMAPK genes ranged from 1 to 10, suggesting large variation among cassava MAPK genes. Conserved motif analysis indicated that all MeMAPKs had typical protein kinase domains. Transcriptomic analysis suggested that MeMAPK genes showed differential expression patterns in distinct tissues and in response to drought stress between wild subspecies and cultivated varieties. Interaction networks and co-expression analyses revealed that crucial pathways controlled by MeMAPK networks may be involved in the differential response to drought stress in different accessions of cassava. Expression of nine selected MAPK genes showed that these genes could comprehensively respond to osmotic, salt, cold, oxidative stressors, and abscisic acid (ABA) signaling. These findings yield new insights into the transcriptional control of MAPK gene expression, provide an improved understanding of abiotic stress responses and signaling transduction in cassava, and lead to potential applications in the genetic improvement of cassava cultivars. PMID:27625666

  15. Genome-Wide Identification and Expression Analysis of the NAC Transcription Factor Family in Cassava.

    Directory of Open Access Journals (Sweden)

    Wei Hu

    Full Text Available NAC [no apical meristem (NAM, Arabidopsis transcription activation factor [ATAF1/2] and cup-shaped cotyledon (CUC2] proteins is one of the largest groups of plant specific transcription factors and plays a crucial role in plant growth, development, and adaption to the environment. Currently, no information is known about the NAC family in cassava. In this study, 96 NAC genes (MeNACs were identified from the cassava genome. Phylogenetic analysis of the NACs from cassava and Arabidopsis showed that MeNAC proteins can be clustered into 16 subgroups. Gene structure analysis found that the number of introns of MeNAC genes varied from 0 to 5, with the majority of MeNAC genes containing two introns, indicating a small gene structure diversity of cassava NAC genes. Conserved motif analysis revealed that all of the identified MeNACs had the conserved NAC domain and/or NAM domain. Global expression analysis suggested that MeNAC genes exhibited different expression profiles in different tissues between wild subspecies and cultivated varieties, indicating their involvement in the functional diversity of different accessions. Transcriptome analysis demonstrated that MeNACs had a widely transcriptional response to drought stress and that they had differential expression profiles in different accessions, implying their contribution to drought stress resistance in cassava. Finally, the expression of twelve MeNAC genes was analyzed under osmotic, salt, cold, ABA, and H2O2 treatments, indicating that cassava NACs may represent convergence points of different signaling pathways. Taken together, this work found some excellent tissue-specific and abiotic stress-responsive candidate MeNAC genes, which would provide a solid foundation for functional investigation of the NAC family, crop improvement and improved understanding of signal transduction in plants. These data bring new insight on the complexity of the transcriptional control of MeNAC genes and support the

  16. Genome-Wide Identification and Expression Analysis of the NAC Transcription Factor Family in Cassava.

    Science.gov (United States)

    Hu, Wei; Wei, Yunxie; Xia, Zhiqiang; Yan, Yan; Hou, Xiaowan; Zou, Meiling; Lu, Cheng; Wang, Wenquan; Peng, Ming

    2015-01-01

    NAC [no apical meristem (NAM), Arabidopsis transcription activation factor [ATAF1/2] and cup-shaped cotyledon (CUC2)] proteins is one of the largest groups of plant specific transcription factors and plays a crucial role in plant growth, development, and adaption to the environment. Currently, no information is known about the NAC family in cassava. In this study, 96 NAC genes (MeNACs) were identified from the cassava genome. Phylogenetic analysis of the NACs from cassava and Arabidopsis showed that MeNAC proteins can be clustered into 16 subgroups. Gene structure analysis found that the number of introns of MeNAC genes varied from 0 to 5, with the majority of MeNAC genes containing two introns, indicating a small gene structure diversity of cassava NAC genes. Conserved motif analysis revealed that all of the identified MeNACs had the conserved NAC domain and/or NAM domain. Global expression analysis suggested that MeNAC genes exhibited different expression profiles in different tissues between wild subspecies and cultivated varieties, indicating their involvement in the functional diversity of different accessions. Transcriptome analysis demonstrated that MeNACs had a widely transcriptional response to drought stress and that they had differential expression profiles in different accessions, implying their contribution to drought stress resistance in cassava. Finally, the expression of twelve MeNAC genes was analyzed under osmotic, salt, cold, ABA, and H2O2 treatments, indicating that cassava NACs may represent convergence points of different signaling pathways. Taken together, this work found some excellent tissue-specific and abiotic stress-responsive candidate MeNAC genes, which would provide a solid foundation for functional investigation of the NAC family, crop improvement and improved understanding of signal transduction in plants. These data bring new insight on the complexity of the transcriptional control of MeNAC genes and support the hypothesis that

  17. Evaluation of Jatropha curcas as an alternative host of African cassava mosaic virus

    International Nuclear Information System (INIS)

    A study was conducted to evaluate ten local accessions of Jatropha curcas L. (physic nut) as an alternative host of African cassava mosaic virus (ACMV). The ten local accessions of J. curcas were planted in a field trial at the research farm of the Biotechnology and Nuclear Agriculture Research Institute, intercropped with ACMV-infected cassava cultivar 'Afisiafi' and left to natural spread of ACMV from the cassava to J. curcas. The J. curcas plants which became infected generally showed mild symptoms, with severity ranging from 1.00 at eight weeks after planting (WAP) to 3.00 at 16 WAP on a scale of 1 (no symptoms) to 5 (severe symptoms). Whitefly populations recorded on the J. curcas accessions in the wet (Sept. - Oct., 2008) and dry (Jan. - Feb., 2009) seasons were generally low. However, significant differences (p < 0.05) were found in the mean whitefly numbers found on the individual J. curcas accessions in the dry season. Disease incidence as determined by symptom expression varied among accessions at eight, twelve and sixteen weeks after planting, though the differences not statistically significant. Leaf samples from the ten J. curcas accessions were tested at six, nine and twelve months after planting (MAP) for the presence of ACMV by enzyme-linked immunosorbent assays (ELISA) and by polymerase chain reaction (PCR). ELISA tests using monoclonal antibody SCRI 33, in a double antibody sandwich ELISA (DAS-ELISA) showed ACMV infection in the J. curcas accessions. Infection ranged from 0% at 6MAP to 50% at 12MAP. Molecular analysis by PCR with a virus-specific primer (JSP001/JSP002) of the viral DNA extracted from leaves of the number of samples tested, as against 37.7% by ELISA. Infection among the accessions as shown by to PCR varied significantly (p < 0.05) and ranged from as low as 16.6% to as high as 91.6%. ACMV infection of the J. curcas plants was further confirmed by infectivity tests on Nicotiana benthamiana indicator plants. Three of (3) out of 132

  18. Evaluating Changes In Fertility Status Of An Alfisol Under Different Growth Stages Of Cassava Manihot Esculenta Crantz

    Directory of Open Access Journals (Sweden)

    B. Osundare

    2015-02-01

    Full Text Available Abstract Evaluating changes in soil nutrient status under different growth stages of cassava makes possible determination of the most critical stage in its vegetative growth phase when its demand for nutrients is highest. Determining the most critical stage in cassava vegetative growth phase when its nutrient demand is highest will enhance properly timed fertilizer application in such a way the application will coincide with the most critical stage in cassava vegetative phase when its demand for nutrients is highest. In view of this a two year field experiment was designed to assess changes in nutrient status of an Alfisol under different growth stages of cassava during 2010 and 2011 cropping seasons at the Teaching and Research Farm of the Ekiti State University Ado Ekiti Ekiti State Nigeria. The experiment was laid out in a randomized complete block design with three replicates. The different growth stages of cassava when changes in nutrient status of Alfisol were evaluated included 3 6 9 and 12 months after planting MAP. The results indicated existence of significant P 0.05 differences among the different growth stages of cassava as regards their effects on chemical properties of Alfisol. During 2010 cropping season the significant decreases in soil organic carbon SOC under growth stages of cassava were from 0.96 g kg-1 for ISNSPTC to 0.88 0.80 0.72 and0.64 g kg-1 for ages 3 6 9 and 12 MAP respectively. Similarly during 2011 cropping season the significant decreases in soil organic carbon SOC under growth stages of cassava were from 0.96 g kg-1 for ISNSPTC to 0.80 0.73 0.66 and0.58 g kg-1 for ages 3 6 9 and 12 MAP respectively. During 2010 cropping season the significant decreases in total N under growth stages of cassava were from 0.68 g kg-1 for ISNSPTC to 0.57 0.50 0.43 and0.35 g kg-1 for ages 3 6 9 and 12 MAP respectively. During 2011 cropping season the significant decreases in total N under growth stages of cassava were from 0.68 g kg-1

  19. 国内木薯病害普查及细菌性萎蔫病安全性评估%General Survey on Cassava Diseases and Safety Assessment of Cassava Bacterial Blight

    Institute of Scientific and Technical Information of China (English)

    李超萍; 时涛; 刘先宝; 蔡吉苗; 裴月令; 黄贵修

    2011-01-01

    2007~2010年,对广西、海南、云南等木薯主产区进行病害普查.结果发现,至今危害国内木薯的主要病害有7种,包括真菌病害6种[褐斑病(Cercosporidium henningsii)、炭疽病(colletotrichum gloeosPorioides)、离孺孢叶斑病(Bipolaris setariae)、棒孢霉叶斑病(Corynespora cassiicola)、白点病(phaeoramularia manihotis)和萎蔫叶斑病(Cercospora vicosae)],细菌病害1种[细菌性萎蔫病(Xanthomonas axonopodis pv manihotis)],其中离孺孢叶斑病和棒孢霉叶斑病为新发病害;7种病害中褐斑病和细菌性萎蔫病发生面积最大,危害最为严重.风险评估结果表明,细菌性萎蔫病菌为高度危险性有害生物.%During 2007 to 2010, cassava(Manihot esculenta Crantz)diseases survey was conducted in Guangxi, Hainan and Yunnan, the main cassava planting areas of China. The results showed that only seven diseases, six fungal diseases and one bacterial disease, were found. The cassava brown leaf spot caused by Cercosporidium henningsii and the bacterial blight caused by Xanthomonas axonopodis pv Manihotis prevailed in most cassava planting areas and caused serious damage. The safety assessment indicated that the cassava bacterial blight was a high risk disease. At present, cassava diseases are becoming one of the most important limiting factors for the development of cassava industry and would have a very serious,potential economic risk on correlative industry and the ecology of the tropic area.

  20. Biological Implications in Cassava for the Production of Amylose-Free Starch: Impact on Root Yield and Related Traits.

    Science.gov (United States)

    Karlström, Amanda; Calle, Fernando; Salazar, Sandra; Morante, Nelson; Dufour, Dominique; Ceballos, Hernán

    2016-01-01

    Cassava (Manihot esculenta, Crantz) is an important food security crop, but it is becoming an important raw material for different industrial applications. Cassava is the second most important source of starch worldwide. Novel starch properties are of interest to the starch industry, and one them is the recently identified amylose-free (waxy) cassava starch. Waxy mutants have been found in different crops and have been often associated with a yield penalty. There are ongoing efforts to develop commercial cassava varieties with amylose-free starch. However, little information is available regarding the biological and agronomic implications of starch mutations in cassava, nor in other root and tuber crops. In this study, siblings from eight full-sib families, segregating for the waxy trait, were used to determine if the mutation has implications for yield, dry matter content (DMC) and harvest index in cassava. A total of 87 waxy and 87 wild-type starch genotypes from the eight families were used in the study. The only significant effect of starch type was on DMC (p < 0.01), with waxy clones having a 0.8% lower content than their wild type counterparts. There was no effect of starch type on fresh root yield (FRY), adjusted FRY and harvest index. It is not clear if lower DMC is a pleiotropic effect of the waxy starch mutation or else the result of linked genes introgressed along with the mutation. It is expected that commercial waxy cassava varieties will have competitive FRYs but special efforts will be required to attain adequate DMCs. This study contributes to the limited knowledge available of the impact of starch mutations on the agronomic performance of root and tuber crops. PMID:27242813

  1. Involvement of miR160/miR393 and their targets in cassava responses to anthracnose disease.

    Science.gov (United States)

    Pinweha, Nattaya; Asvarak, Thipa; Viboonjun, Unchera; Narangajavana, Jarunya

    2015-02-01

    Cassava is a starchy root crop for food and industrial applications in many countries around the world. Among the factors that affect cassava production, diseases remain the major cause of yield loss. Cassava anthracnose disease is caused by the fungus Colletotrichum gloeosporioides. Severe anthracnose attacks can cause tip die-backs and stem cankers, which can affect the availability of planting materials especially in large-scale production systems. Recent studies indicate that plants over- or under-express certain microRNAs (miRNAs) to cope with various stresses. Understanding how a disease-resistant plant protects itself from pathogens should help to uncover the role of miRNAs in the plant immune system. In this study, the disease severity assay revealed different response to C. gloeosporioides infection in two cassava cultivars. Quantitative RT-PCR analysis uncovered the differential expression of the two miRNAs and their target genes in the two cassava cultivars that were subjected to fungal infection. The more resistant cultivar revealed the up-regulation of miR160 and miR393, and consequently led to low transcript levels in their targets, ARF10 and TIR1, respectively. The more susceptible cultivar exhibited the opposite pattern. The cis-regulatory elements relevant to defense and stress responsiveness, fungal elicitor responsiveness and hormonal responses were the most prevalent present in the miRNAs gene promoter regions. The possible dual role of these specific miRNAs and their target genes associated with cassava responses to C. gloeosporioides is discussed. This is the first study to address the molecular events by which miRNAs which might play a role in fungal-infected cassava. A better understanding of the functions of miRNAs target genes should greatly increase our knowledge of the mechanism underlying susceptibility and lead to new strategies to enhance disease tolerance in this economically important crop.

  2. Effects of citric acid esterification on digestibility, structural and physicochemical properties of cassava starch.

    Science.gov (United States)

    Mei, Ji-Qiang; Zhou, Da-Nian; Jin, Zheng-Yu; Xu, Xue-Ming; Chen, Han-Qing

    2015-11-15

    In this study, citric acid was used to react with cassava starch in order to compare the digestibility, structural and physicochemical properties of citrate starch samples. The results indicated that citric acid esterification treatment significantly increased the content of resistant starch (RS) in starch samples. The swelling power and solubility of citrate starch samples were lower than those of native starch. Compared with native starch, a new peak at 1724 cm(-1) was appeared in all citrate starch samples, and crystalline peaks of all starch citrates became much smaller or even disappeared. Differential scanning calorimetry results indicated that the endothermic peak of citrate starches gradually shrank or even disappeared. Moreover, the citrate starch gels exhibited better freeze-thaw stability. These results suggested that citric acid esterification induced structural changes in cassava starch significantly affected its digestibility and it could be a potential method for the preparation of RS with thermal stability.

  3. Cassava and turmeric flour blends as new raw materials to extruded snacks

    Directory of Open Access Journals (Sweden)

    Alessandra Mussato Spinello

    2014-02-01

    Full Text Available Short cooking time and ability to blend varieties of food ingredients have made extrusion cooking a medium for low-cost and nutritionally improved food products. The effect of moisture, extrusion temperature and amount of turmeric flour mixed with cassava flour on physical characteristic of puffed snacks was evaluated in this work. Extrusion process was carried out using a single-screw extruder in a factorial central composite design with four factors. Results showed effect of extrusion parameters on dependents variables. High expansion, low browning, low water solubility index, intermediate water absorption index and high crispness desirable characteristics to puffed snacks are obtained in conditions of 12% moisture, 5% turmeric flour, 105º C of temperature and 250 rpm of screw speed. These paper point to the potential still unexplored of the use of flours of cassava and turmeric as raw materials in the development of extruded puffed snacks.

  4. Mathematical modelling of the thin layer solar drying of banana, mango and cassava

    Energy Technology Data Exchange (ETDEWEB)

    Koua, Kamenan Blaise; Fassinou, Wanignon Ferdinand; Toure, Siaka [Laboratoire d' Energie Solaire, Universite de Cocody- Abidjan, 22 BP 582 Abidjan 22 (Ivory Coast); Gbaha, Prosper [Laboratoire d' Energie Nouvelle et Renouvelable, Institut National Polytechnique, Felix HOUPHOUET - BOIGNY de Yamoussoukro (Ivory Coast)

    2009-10-15

    The main objectives of this paper are firstly to investigate the behaviour of the thin layer drying of plantain banana, mango and cassava experimentally in a direct solar dryer and secondly to perform mathematical modelling by using thin layer drying models encountered in literature. The variation of the moisture content of the products studied and principal drying parameters are analysed. Seven statistical models, which are empirical or semi-empirical, are tested to validate the experimental data. A non-linear regression analysis using a statistical computer program is used to evaluate the constants of the models. The Henderson and Pabis drying model is found to be the most suitable for describing the solar drying curves of plantain banana, mango and cassava. The drying data of these products have been analysed to obtain the values of the effective diffusivity during the falling drying rate phase. (author)

  5. Assay of Antioxidant Potential of Two Filamentous Fungi Isolated from the Indonesian Fermented Dried Cassava.

    Science.gov (United States)

    Sugiharto, Sugiharto; Yudiarti, Turrini; Isroli, Isroli

    2016-02-02

    The antioxidant capacity and antioxidant constituents of two filamentous fungi (Acremonium charticola and Rhizopus oryzae) isolated from the Indonesian fermented dried cassava (gathot) were evaluated in the present study. The antioxidant capacity of the fungal crude extracts was assessed based on the 2,2'-azino-bis(3-ethyl-benzthiazolin-6-sulfonicacid) (ABTS) method. Total phenolics were determined based on the Folin-Ciocalteu method, while the flavonoids content in the fungal extracts was determined by the spectrophotometric method with aluminum chloride. Total tannins were estimated by the Folin-Denis method. The ABTS⁺ radical scavenging activity was higher (p Indonesian fermented dried cassava exhibited antioxidant potentials as indicated by their capabilities to scavenge ABTS⁺. A. charticola had a higher antioxidant capacity than R. oryzae. The antioxidant capacity of A. charticola was attributed mainly to its phenolics and tannins contents.

  6. Analysis of Cassava Product (Garri Marketing in Ekiti Local Government Area, Kwara State, Nigeria

    Directory of Open Access Journals (Sweden)

    Olasore Abiodun Amos

    2013-10-01

    Full Text Available This study is on analysis of cassava product (garri marketing in Ekiti Local Government Area, Kwara State, Nigeria. Data for the study were obtained from 150 respondents from the target group using a two-stage sampling procedure and analyzed using descriptive statistics, Gini Coefficient and Lorenz Curve. Gini Coefficient for all cassava product traders was estimated to be 0.624 or 62.4%. The estimated Gini Coefficient show high degree of inequality in the sales/income distribution. The Lorenz Curve plotted further revealed sales/income inequality among the traders. A wide gap between line of inequality and the plotted Lorenz Curve showed that there is a high inequality in the distribution of income among traders.

  7. Consumer acceptability of stiff porridge based on various composite flour proportions of sorghum, maize and cassava.

    Science.gov (United States)

    Bangu, N T; Mtebe, K; Nzallawahe, T S

    1994-12-01

    A study was conducted to determine consumer acceptable proportions of flours in sorghum (var. serena) and maize or sorghum, maize and cassava composite flours. Breeder's serena flour extracted at 75 percent was mixed at various proportions with maize or with maize and cassava to constitute composite flours. The various composite flours were made into stiff porridge and presented to a group of panellists for sensory evaluation. The evaluation was conducted by scoring on a hedonic scale of 0-5 for poor to excellent, respectively, for the parameters colour, texture, flavour, taste and overall acceptability. The responses were analysed statistically. Alternatively the panellists were allowed to eat ad-lib any of the presented samples which appealed to them. The results demonstrated that slight incorporation (porridge overrides other factors in contributing to its acceptability.

  8. Evaluation of phenotypic stability of cassava clones by AMMI analysis in northwestern Paraná state

    Directory of Open Access Journals (Sweden)

    Marcus Vinícius Kvitschal

    2006-01-01

    Full Text Available High yield stability and adaptability of storage root are highly desirable attributes of cassava clones. Theobjective of this study was therefore to evaluate the effect of the genotype x environment interaction (G x E and the stability ofcassava clones developed at IAC. A subset of eight cassava genotypes was chosen in trials of storage root yield, arranged ina randomized complete block design with four replications, in two counties (Araruna and Maringá, in the northwesternregion of Paraná State, over five growing seasons (1997-2001. The G x E interaction was evaluated by joint varianceanalysis and stability and adaptability by AMMI analysis. The G x E interaction was significant (P<0.05 for storage rootyield. Results indicated AMMI analysis as an efficient tool for the evaluation of phenotypic adaptability and stability of cassavaclones and IAC 190 as the most promising clone.

  9. Culture conditions for yellow pigment formation byMonascus sp. KB 10 grown on cassava medium.

    Science.gov (United States)

    Yongsmith, B; Tabloka, W; Yongmanitchai, W; Bavavoda, R

    1993-01-01

    An isolate ofMonascus, from a commercial, fermented soybean curd (sufu) was grown on a cassava medium. With medium at an initial pH of 7.0 an orange-red pigmentation was produced but with an initial pH below 4, a light golden pigment was obtained. A medium containing, w/v, 3% cassava starch, 0.4% peptone and 0.1% glutamic acid, with an initial pH of 2.5 was optimal for the production of this yellow pigment, which had a single maximum absorption spectrum at 330 nm. The spectroscopic characterization of the purified yellow pigments demonstrated a monascin-ankaflavin-monascorubrin skeleton.

  10. Soil mycoflora of banana and cassava in peatland and alluvial soil in Bengkulu

    Directory of Open Access Journals (Sweden)

    SUCIATMIH

    2006-10-01

    Full Text Available In order to discover the diversity and population of soil fungi, a study was carried out at banana (Musa paradisiaca and cassava (Manihot utilissima plants where both those plants planted in peatland and alluvial soil. Soil fungi were isolated using serial dilution plate method and they were incubated at both room temperature (27-28oC and 45oC. This process was replicated two times for each sample. The result indicated that from 4 soil samples, 24 genera of fungi representing 4 Ascomycotina, 15 Deuteromycotina, and 5 Zygomycotina were detected. The highest soil fungi population was found in cassava planted in peat land and incubated at room temperature (8.5 105 cfu/ g dry soil, while the lower soil fungi population came from banana plant that was planted in peat land and incubated at 45oC (7.1 103 cfu/g dry soil.

  11. Cassava Starch Edible Film Incorporated with Lemongrass Oil: Characteristics and Application

    Directory of Open Access Journals (Sweden)

    Muhammad Dani Supardan

    2016-04-01

    Full Text Available The objective of this research is to evaluate the effect of the addition of lemongrass essential oil (LGO on the characteristics and antimicrobial properties of cassava starch based films. Edible films were prepared from a mixture of cassava starch and glycerol. LGO was added to edible films as natural antimicrobial agent. There was a reduction in tensile strength of edible film because of incorporation of LGO. The presence of LGO also caused to a reduction in roughness of the edible film. The experimental results showed that Trichoderma and Penicillium was not appear upon the film until the third day of incubation. Meanwhile, the use of edible films containing LGO as antimicrobial agents caused to a reduction in microbial counts of meat during storage.

  12. Response of Cassava canopy to mid-day pseudo sunrise induced by solar eclipse

    Science.gov (United States)

    Latha, R.; Murthy, B. S.

    2013-07-01

    Variations in CO2 concentration over a cassava canopy were measured during a solar eclipse at Thiruvananthapuram, India. The analysis presented attempts to differentiate between the eclipse effect and the possible effect of thick clouds, taking CO2 as a proxy for photosynthesis. CO2 and water vapor were measured at a rate of 10 Hz, and radiation at 1 Hz, together with other meteorological parameters. A rapid reduction in CO2 observed post-peak eclipse, due apparently to intense photosynthesis, appears similar to what happens at daybreak/post-sunrise. The increase in CO2 (4 ppm) during peak eclipse, with radiation levels falling below the photosynthesis cut-off for cassava, indicates domination of respiration due to the light-limiting conditions.

  13. Preparation of metal adsorbent from poly(methyl acrylate)-grafted-cassava starch via gamma irradiation

    Science.gov (United States)

    Suwanmala, Phiriyatorn; Hemvichian, Kasinee; Hoshina, Hiroyuki; Srinuttrakul, Wannee; Seko, Noriaki

    2012-08-01

    Metal adsorbent containing hydroxamic acid groups was successfully synthesized by radiation-induced graft copolymerization of methyl acrylate (MA) onto cassava starch. The optimum conditions for grafting were studied in terms of % degree of grafting (Dg). Conversion of the ester groups present in poly(methyl acrylate)-grafted-cassava starch copolymer into hydroxamic acid was carried out by treatment with hydroxylamine (HA) in the presence of alkaline solution. The maximum percentage conversion of the ester groups of the grafted copolymer, % Dg=191 (7.63 mmol/g of MA), into the hydroxamic groups was 70% (5.35 mmol/g of MA) at the optimum condition. The adsorbent of 191%Dg had total adsorption capacities of 2.6, 1.46, 1.36, 1.15 and 1.6 mmol/g-adsorbent for Cd2+, Al3+, UO22+, V5+ and Pb2+, respectively, in the batch mode adsorption.

  14. Polymeric flocculant based on cassava starch grafted polydiallyldimethylammonium chloride: Flocculation behavior and mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Razali, M.A.A.; Ariffin, A., E-mail: srazlan@usm.my

    2015-10-01

    Graphical abstract: - Highlights: • Flocculation performance of cassava grafted polyDADMAC was studied. • Turbidity and TSS removal increased with increasing grafting percentage. • The grafted polymer showed good removal in acidic and neutral region. • Zeta potential results pointed to the charge neutralization mechanism. • Flocs increased with increasing grafting percentage and molecular weight. - Abstract: In this work, flocculation properties of cassava starch grafted polydiallyldimethylammonium chloride (polyDADMAC) with different grafting percentages were investigated. Flocculation performance was evaluated in simulated kaolin suspension. The grafting percentages used were 1.76 %, 14.84 %, and 21.98 %. The effectiveness of the flocculation was measured based on the reduction of the turbidity and total suspended solids (TSSs), zeta potential measurements, particle size, and atomic force microscopy imaging. Grafted polymers improved the removal rate of turbidity and TSS compared with gelatinized starch, and the removal rate increased with increasing grafting percentage and dosage.

  15. Microbial control of the invasive spiraling whitefly on cassava with entomopathogenic fungi

    Directory of Open Access Journals (Sweden)

    Thangavel Boopathi

    2015-01-01

    Full Text Available AbstractThe entomopathogenic fungi Beauveria bassiana, Metarhizium anisopliae, Lecanicillium lecanii and Isaria fumosorosea were tested for their efficacy in managing the exotic spiraling whitefly Aleurodicus dispersus (Hemiptera, Aleyrodidae on cassava (Manihot esculenta during 2 seasons (2011-2012 and 2012-2013. The fungi I. fumosorosea and L. lecanii exhibited promising levels of control (> 70% mortality of the A. dispersus population. The percent mortality increased over time in both seasons. Application of I. fumosorosea was highly pathogenic to A. dispersusin both seasons compared to the other entomopathogenic fungi. Analysis of the percent mortality in both seasons revealed differences in efficacy between 3 and 15 days after treatment. The season also influenced the effects of the fungi on the A. dispersus population. Thus, entomopathogenic fungi have the potential to manage A. dispersus infestation of cassava.

  16. Gamma radiation use to avoid enzymatic browning of cassava root (Manihot utilissima Pohl) in natura, peeled

    International Nuclear Information System (INIS)

    Cassava root was treated with gamma radiation at doses of 2, 4, 6, 8 and 10 kGy to avoid enzymatic browning. The irradiated samples were kept for 9 days at room temperature and evaluated for color and sensorial analysis. Two days after harvest, the control sample showed black spots and alterations of organoleptic characteristics. The irradiated sample with 2 to 6 kGy showed good appearance and acceptability. However, after 9 days of storage, the control and the irradiated (2 to 6 kGy) samples were not safe to eat, only the irradiated cassava with doses of 8 and 10 kGy did not show enzymatic browning and kept the good sensorial characteristics. (author)

  17. Effect of acid additives on grafting efficiency and water absorption of hydrolyzed cassava starch grafted polymers

    International Nuclear Information System (INIS)

    Gelatinized cassava starch was radiation graft copolymerized with acrylamide, acrylic acid or their mixture in the presence of sulphuric acid or maleic acid. Various acid concentrations were used from 0.001 to 0.1 M of sulphuric acid while the maleic acid concentrations were varied from 1 to 3% (by weight). The optimum total dose and dose rate were investigated. The saponification temperature and time had the marked effects on grafting characteristics and water absorption capacity. We found that the effect of maleic acid addition gave a profound effect on water absorption. The CHNS/O analyses indicated significant changes in the nitrogen content in the hydrolyzed starch grafted polyacrylamide with 2% maleic acid. The article explains the possible causes for the enhancement influence of mineral acid and maleic acid on grafting behavior and water absorption of the saponified cassava starch grafted polyacrylamide super absorbent polymer. (author)

  18. Assay of Antioxidant Potential of Two Filamentous Fungi Isolated from the Indonesian Fermented Dried Cassava.

    Science.gov (United States)

    Sugiharto, Sugiharto; Yudiarti, Turrini; Isroli, Isroli

    2016-01-01

    The antioxidant capacity and antioxidant constituents of two filamentous fungi (Acremonium charticola and Rhizopus oryzae) isolated from the Indonesian fermented dried cassava (gathot) were evaluated in the present study. The antioxidant capacity of the fungal crude extracts was assessed based on the 2,2'-azino-bis(3-ethyl-benzthiazolin-6-sulfonicacid) (ABTS) method. Total phenolics were determined based on the Folin-Ciocalteu method, while the flavonoids content in the fungal extracts was determined by the spectrophotometric method with aluminum chloride. Total tannins were estimated by the Folin-Denis method. The ABTS⁺ radical scavenging activity was higher (p cassava exhibited antioxidant potentials as indicated by their capabilities to scavenge ABTS⁺. A. charticola had a higher antioxidant capacity than R. oryzae. The antioxidant capacity of A. charticola was attributed mainly to its phenolics and tannins contents. PMID:26848695

  19. Super absorbent Prepared by Radiation Induced Graft Copolymerization of Acrylic Acid onto Cassava Starch

    International Nuclear Information System (INIS)

    Full text: Super absorbent was synthesized by radiation-induced graft polymerization of acrylic acid onto cassava starch. Parameters such as the absorbed dose and the amount of monomer were investigated in order to determine the optimum conditions for the grafting polymerization. Water retention, germination percentage and germination energy were determined in order to evaluate the possibility of super absorbent in agricultural applications, especially in arid regions. The graft copolymer was characterized by FTIR. Results indicated that the sand mixed with 0.1%wt super absorbent can absorb more water than the sand without super absorbent. The germination energy of corn seeds mixed with 0.5% super absorbent was obviously higher than those without super absorbent. These experimental results showed that the super absorbent has considerable effect on seed germination and the growth of young plants. Keywords: Super absorbent, Radiation, Acrylic acid, Cassava starch

  20. Polymeric flocculant based on cassava starch grafted polydiallyldimethylammonium chloride: Flocculation behavior and mechanism

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • Flocculation performance of cassava grafted polyDADMAC was studied. • Turbidity and TSS removal increased with increasing grafting percentage. • The grafted polymer showed good removal in acidic and neutral region. • Zeta potential results pointed to the charge neutralization mechanism. • Flocs increased with increasing grafting percentage and molecular weight. - Abstract: In this work, flocculation properties of cassava starch grafted polydiallyldimethylammonium chloride (polyDADMAC) with different grafting percentages were investigated. Flocculation performance was evaluated in simulated kaolin suspension. The grafting percentages used were 1.76 %, 14.84 %, and 21.98 %. The effectiveness of the flocculation was measured based on the reduction of the turbidity and total suspended solids (TSSs), zeta potential measurements, particle size, and atomic force microscopy imaging. Grafted polymers improved the removal rate of turbidity and TSS compared with gelatinized starch, and the removal rate increased with increasing grafting percentage and dosage