Household utilization of Manioc (Manihot esculenta Crantz) in Northern Mozambique.
Muoki, Penina N; Maziya-Dixon, Bussie
2010-01-01
Mozambique is ranked ninth of top manioc (Manihot esculenta Crantz) producing countries in the world. Manioc roots are a staple to people living in the northern part of the country. Despite this, information on production, utilization, postharvest handling, and marketing is scarce. The purpose of this baseline study was to document selected information on manioc, from the production to marketing stage. To gather this information, 70 focus groups consisting of 1,724 participants purposely sampled from 10 districts were engaged in discussions using a questionnaire. The results show that manioc is the most important crop in terms of contribution to household food security and income in the region. Both men and women participate in the delivery of manioc production chain. Typically, 5 to 15 varieties identified by local language can be found on most farms in the study area. Manioc leaves and roots are the parts of the plant used as human food. Sun dried manioc roots are principally marketed within the locality of production by individual farmers. This baseline study suggests the need for location-targeted interventions as the farmers reported varied challenges along the manioc production chain.
Fraser, James Angus; Alves-Pereira, Alessandro; Junqueira, André Braga; Peroni, Nivaldo; Clement, Charles Roland
2012-01-01
Shifting cultivation in the humid tropics is incredibly diverse, yet research tends to focus on one type: long-fallow shifting cultivation. While it is a typical adaptation to the highly-weathered nutrient-poor soils of the Amazonian terra firme, fertile environments in the region offer opportunities for agricultural intensification. We hypothesized that Amazonian people have developed divergent bitter manioc cultivation systems as adaptations to the properties of different soils. We compared bitter manioc cultivation in two nutrient-rich and two nutrient-poor soils, along the middle Madeira River in Central Amazonia. We interviewed 249 farmers in 6 localities, sampled their manioc fields, and carried out genetic analysis of bitter manioc landraces. While cultivation in the two richer soils at different localities was characterized by fast-maturing, low-starch manioc landraces, with shorter cropping periods and shorter fallows, the predominant manioc landraces in these soils were generally not genetically similar. Rather, predominant landraces in each of these two fertile soils have emerged from separate selective trajectories which produced landraces that converged for fast-maturing low-starch traits adapted to intensified swidden systems in fertile soils. This contrasts with the more extensive cultivation systems found in the two poorer soils at different localities, characterized by the prevalence of slow-maturing high-starch landraces, longer cropping periods and longer fallows, typical of previous studies. Farmers plant different assemblages of bitter manioc landraces in different soils and the most popular landraces were shown to exhibit significantly different yields when planted in different soils. Farmers have selected different sets of landraces with different perceived agronomic characteristics, along with different fallow lengths, as adaptations to the specific properties of each agroecological micro-environment. These findings open up new avenues for research and debate concerning the origins, evolution, history and contemporary cultivation of bitter manioc in Amazonia and beyond.
Fraser, James Angus; Alves-Pereira, Alessandro; Junqueira, André Braga; Peroni, Nivaldo; Clement, Charles Roland
2012-01-01
Shifting cultivation in the humid tropics is incredibly diverse, yet research tends to focus on one type: long-fallow shifting cultivation. While it is a typical adaptation to the highly-weathered nutrient-poor soils of the Amazonian terra firme, fertile environments in the region offer opportunities for agricultural intensification. We hypothesized that Amazonian people have developed divergent bitter manioc cultivation systems as adaptations to the properties of different soils. We compared bitter manioc cultivation in two nutrient-rich and two nutrient-poor soils, along the middle Madeira River in Central Amazonia. We interviewed 249 farmers in 6 localities, sampled their manioc fields, and carried out genetic analysis of bitter manioc landraces. While cultivation in the two richer soils at different localities was characterized by fast-maturing, low-starch manioc landraces, with shorter cropping periods and shorter fallows, the predominant manioc landraces in these soils were generally not genetically similar. Rather, predominant landraces in each of these two fertile soils have emerged from separate selective trajectories which produced landraces that converged for fast-maturing low-starch traits adapted to intensified swidden systems in fertile soils. This contrasts with the more extensive cultivation systems found in the two poorer soils at different localities, characterized by the prevalence of slow-maturing high-starch landraces, longer cropping periods and longer fallows, typical of previous studies. Farmers plant different assemblages of bitter manioc landraces in different soils and the most popular landraces were shown to exhibit significantly different yields when planted in different soils. Farmers have selected different sets of landraces with different perceived agronomic characteristics, along with different fallow lengths, as adaptations to the specific properties of each agroecological micro-environment. These findings open up new avenues for research and debate concerning the origins, evolution, history and contemporary cultivation of bitter manioc in Amazonia and beyond. PMID:22952727
Alves-Pereira, Alessandro; Peroni, Nivaldo; Cavallari, Marcelo Mattos; Lemes, Maristerra R; Zucchi, Maria Imaculada; Clement, Charles R
2017-01-01
Although manioc is well adapted to nutrient-poor Oxisols of Amazonia, ethnobotanical observations show that bitter manioc is also frequently cultivated in the highly fertile soils of the floodplains and Amazonian dark earths (ADE) along the middle Madeira River. Because different sets of varieties are grown in each soil type, and there are agronomic similarities between ADE and floodplain varieties, it was hypothesized that varieties grown in ADE and floodplain were more closely related to each other than either is to varieties grown in Oxisols. We tested this hypothesis evaluating the intra-varietal genetic diversity and the genetic relationships among manioc varieties commonly cultivated in Oxisols, ADE and floodplain soils. Genetic results did not agree with ethnobotanical expectation, since the relationships between varieties were variable and most individuals of varieties with the same vernacular name, but grown in ADE and floodplain, were distinct. Although the same vernacular name could not always be associated with genetic similarities, there is still a great amount of variation among the varieties. Many ecological and genetic processes may explain the high genetic diversity and differentiation found for bitter manioc varieties, but all contribute to the maintenance and amplification of genetic diversity within the manioc in Central Amazonia.
Alves-Pereira, Alessandro; Peroni, Nivaldo; Cavallari, Marcelo Mattos; Lemes, Maristerra R.; Zucchi, Maria Imaculada; Clement, Charles R.
2017-01-01
Abstract Although manioc is well adapted to nutrient-poor Oxisols of Amazonia, ethnobotanical observations show that bitter manioc is also frequently cultivated in the highly fertile soils of the floodplains and Amazonian dark earths (ADE) along the middle Madeira River. Because different sets of varieties are grown in each soil type, and there are agronomic similarities between ADE and floodplain varieties, it was hypothesized that varieties grown in ADE and floodplain were more closely related to each other than either is to varieties grown in Oxisols. We tested this hypothesis evaluating the intra-varietal genetic diversity and the genetic relationships among manioc varieties commonly cultivated in Oxisols, ADE and floodplain soils. Genetic results did not agree with ethnobotanical expectation, since the relationships between varieties were variable and most individuals of varieties with the same vernacular name, but grown in ADE and floodplain, were distinct. Although the same vernacular name could not always be associated with genetic similarities, there is still a great amount of variation among the varieties. Many ecological and genetic processes may explain the high genetic diversity and differentiation found for bitter manioc varieties, but all contribute to the maintenance and amplification of genetic diversity within the manioc in Central Amazonia. PMID:28399193
Genetic structure of traditional varieties of bitter manioc in three soils in Central Amazonia.
Alves-Pereira, Alessandro; Peroni, Nivaldo; Abreu, Aluana Gonçalves; Gribel, Rogério; Clement, Charles R
2011-10-01
Manioc is the most important food crop that originated in Amazonia. Many studies have increased our understanding of its evolutionary dynamics under cultivation. However, most of them focused on manioc cultivation in environments with low soil fertility, generally Oxisols. Recent ethnobotanical observations showed that bitter manioc also performs well in high fertility soils, such as Amazonian dark earths (ADE) and the floodplain. We used 10 microsatellite loci to investigate the genetic diversity and structure of bitter manioc varieties grown in different soil types in communities of smallholder farmers along the middle Madeira River in Central Amazonia. The genetic diversity of some sweet varieties and seedlings was also evaluated. Adult individuals showed higher levels of genetic diversity and smaller inbreeding coefficients (A ( R ) = 5.52, H ( O ) = 0.576, f = 0.086) than seedlings (A ( R ) = 4.39, H ( O ) = 0.421, f = 0.242). Bitter manioc varieties from the floodplain showed higher levels of genetic diversity (A ( R ) = 5.19, H ( O ) = 0.606) than those from ADE (A ( R ) = 4.45, H ( O ) = 0.538) and from Oxisols (A ( R ) = 4.15, H ( O ) = 0.559). The varieties grown in the floodplain were strongly differentiated from the varieties grown in Oxisols (F ( ST ) = 0.093) and ADE (F ( ST ) = 0.108), suggesting important genetic structuring among varieties grown in the floodplain and upland soils (ADE and Oxisols). This is the first time that genetic divergence of bitter manioc varieties in cultivation in different Amazonian soils in a small geographic area is reported.
Ménard, Léa; McKey, Doyle; Mühlen, Gilda S.; Clair, Bruno; Rowe, Nick P.
2013-01-01
Domestication can influence many functional traits in plants, from overall life-history and growth form to wood density and cell wall ultrastructure. Such changes can increase fitness of the domesticate in agricultural environments but may negatively affect survival in the wild. We studied effects of domestication on stem biomechanics in manioc by comparing domesticated and ancestral wild taxa from two different regions of greater Amazonia. We compared mechanical properties, tissue organisation and wood characteristics including microfibril angles in both wild and domesticated plants, each growing in two different habitats (forest or savannah) and varying in growth form (shrub or liana). Wild taxa grew as shrubs in open savannah but as lianas in overgrown and forested habitats. Growth form plasticity was retained in domesticated manioc. However, stems of the domesticate showed brittle failure. Wild plants differed in mechanical architecture between shrub and liana phenotypes, a difference that diminished between shrubs and lianas of the domesticate. Stems of wild plants were generally stiffer, failed at higher bending stresses and were less prone to brittle fracture compared with shrub and liana phenotypes of the domesticate. Biomechanical differences between stems of wild and domesticated plants were mainly due to changes in wood density and cellulose microfibril angle rather than changes in secondary growth or tissue geometry. Domestication did not significantly modify “large-scale” trait development or growth form plasticity, since both wild and domesticated manioc can develop as shrubs or lianas. However, “finer-scale” developmental traits crucial to mechanical stability and thus ecological success of the plant were significantly modified. This profoundly influenced the likelihood of brittle failure, particularly in long climbing stems, thereby also influencing the survival of the domesticate in natural situations vulnerable to mechanical perturbation. We discuss the different selective pressures that could explain evolutionary modifications of stem biomechanical properties under domestication in manioc. PMID:24023960
de Oliveira, S R; Bion, F M; Lopes, S M; Metri, A C
2001-03-01
The nutritive value of manioc flour (Manihot esculenta) enriched with yeast protein (Saccharomyces cerevisiae) added to a food mixture most frequently consumed by low-income populations was assessed in female Wistar rats (n = 30; 100-120 days old). Animals were divided into three groups, mated and had free access to diets and water. Diets were as follows: beans, rice, yeast-enriched manioc flour (BRYMF17); beans, rice, manioc flour (BRMF13); casein (17% protein) (CAS17). Body weight gains and food consumption were recorded during pregnancy and lactation. At the parturition, the number of pups per litter was recorded and offspring were uniformly distributed (7 pups per litter). Weight gains were determined until weaning (21 days). At weaning two youngs were selected from each litter and individually housed. Weight gains, food consumption and the length of the tail were measured until rats were 70 days old. Rats had their liver and brain removed for protein determination and wet and relative weights. Liver samples were histologically examined. Blood hemoglobin, hematocrit and proteins, as well as the Food Efficiency Ratio (FER), were determined. ANOVA and Tukey's test were used. The experimental diet had not significant effect on pregnant and lactating dams. Values for the investigated parameters were higher in experimental youngs than in their controls and lower than in the standard group. This yeast protein-enriched manioc flour proved to be valid in terms of dietary supplementation.
Jiménez, María Eugenia; Sammán, Norma
2014-06-01
There is great interest in consuming foods that can provide the nutrients for a good nutrition and other health beneficial compounds. The aim of this work was to determine the chemical composition of native foods of the Andean region and to quantify some functional com-ponents. Proximal composition, vitamin C, total phenolic compounds, antiradical activity (DPPH) in peel and pulp, dietary fiber soluble and insoluble, fructooligosaccharides (FOS), total and resistant starch (in tubers and raw roots, boiled and boiled and stored) of 6 varieties of Oca (Oxalis tuberosa), 4 clones of manioc (Manihot esculenta Crantz) and yacon (Smallanthus sonchifolius were determined. The results showed greater amount of bioactive compounds and antiradical activity in the skin of these products. The highest content was found in the oca peel. In all cases, the content of insoluble fiber was greater than the soluble. The manioc had higher total starch than Andean roots and tubers. The boiling process decreased the resistant starch content of ocas and maniocs, but when these are stored for 48 h at 5 ° C, the resistant starch content increased. The FOS content of the ocas was similar for all varieties (7%). The main component of yacon carbohydrates were FOS (8.89%). The maniocs did not contain FOS. It can be concluded that the roots and tubers studied, in addition to provide nutrients, contain functional compounds that confer additional helpful value for preventing no communicable diseases.
Irish, J D; Turner, C G
1997-01-01
To date, the distinctive dental wear pattern known as LSAMAT, or "lingual surface attrition of the maxillary anterior teeth," has been documented in prehistoric samples from Brazil, Panama, and Puerto Rico only. However, new data from a historic Senegalese sample reveals the first example of this wear pattern outside the Americas. The Senegal LSAMAT is present in 45% of 22 adult crania, and is associated with a caries rate of 40% in 38 adults (6.7% of 534 permanent teeth). A correlation between LSAMAT and caries was also observed in the Latin American samples. In these cases, it was hypothesized that LSAMAT was caused by the specialized consumption of an abrasive, high carbohydrate food, such as manioc. Manioc is a common cultigen in Senegal; thus, it may have also caused the African LSAMAT. The chewing of sugar cane could have been an additional, contributing factor.
Application of genetics to the development of starch-fermenting yeasts
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mattoon, J.R.; Kim, K.; Laluce, C.
1987-01-01
Yeast strains capable of direct fermentation of manioc starch were developed by hybridizing strains of Saccharomyces diastaticus and Saccharomyces cerevisiae. Hybrids were evaluated for speed of alcohol production, and yields and speed of formation of glycoamylase. Up to 6% solutions of Lintner starch could be fermented directly with about 80% conversion to alcohol. Pretreatment of crude 40% manioc starch suspensions with alpha-amylase, followed by fermentations with a starch-fermenting yeast strain, permitted accumulation of 12% ethanol within three days. Starch conversion was almost 100%. A fragment of DNA was cloned from S. diastaticus using the yeast-E. coli shuttle vector, YEp13, andmore » was used to transform a strain of S. cerevisiae to a starch-fermenting state. Supported by National Science Foundation grant INT 7927328 and National Institutes of Health grant GM 27860. Dr. Laluce was supported by a grant from Fundacao de Amparo a Pesquisa do Estado do Sao Paulo and by her university. (Refs. 5).« less
Fat substitutes in processing of sausages using piramutaba waste.
de Fátima Henriques Lourenço, Lúcia; Dos Santos Galvão, Giane Célia; da Conceição Amaral Ribeiro, Suezilde; de Fátima Amaral Ribeiro, Carmelita; Park, Kil Jin
2014-07-01
The aim of this study was to evaluate fat substitute in processing of sausages prepared with surimi of waste from piramutaba filleting. The formulation ingredients were mixed with the fat substitutes added according to a fractional planning 2(4-1), where the independent variables, manioc starch (Ms), hydrogenated soy fat (F), texturized soybean protein (Tsp) and carrageenan (Cg) were evaluated on the responses of pH, texture (Tx), raw batter stability (RBS) and water holding capacity (WHC) of the sausage. Fat substitutes were evaluated in 11 formulations and the results showed that the greatest effects on the responses were found to Ms, F and Cg, being eliminated from the formulation Tsp. To find the best formulation for processing piramutaba sausage was made a complete factorial planning of 2(3) to evaluate the concentrations of fat substitutes in an enlarged range. The optimum condition found for fat substitutes in the sausages formulation were carrageenan (0.51%), manioc starch (1.45%) and fat (1.2%).
NASA Astrophysics Data System (ADS)
Barbosa Lima, Amanda; Westphal Muniz, Aleksander; Lenhart, Katharina; Moser, Gerald; Brenzinger, Kristof; Ha, Mi-Kyung; Eckhardt, Christian; Steffens, Diedrich; Kammann, Claudia; Müller, Christoph
2017-04-01
Amazonian Dark Earth (ADE) in the Brazilian Amazon provide a strong indication that soils lacking in nutrients can be converted into highly fertile land. These soils have been considered as a model soil when compared to the surrounding soil due to the high concentrations of P, Ca, Mg, Zn, Mn, stable organic matter and soil organic C (SOC). Soils with high SOC contents can lead to extensive emissions of the greenhouse gas N2O. In this context, we measured the fluxes of CO2, N2O and CH4 in ADE and adjacent (ADJ) soils under secondary forest and manioc plantation. Moreover, we added 15N-NH4+ and -NO3- and measured N2O emissions and gross-N transformations of the different N species for two weeks (15N signal, N concentrations; work on-going), to quantify the simultaneousyl operating N transformation rates (method see: Müller et al. (2004; 2007). We observed higher amounts of NO3- in both ADE and ADJ soils under forest. High consumption rates for NH4+ were shown by both ADE soils under forest followed by manioc plantation. CO2 effluxes from ADJ were higher than from ADE soils, and higher from the forest compared to the manioc plantation. N2O fluxes were much lower in ADE under forest and higher in the other soils. The results of the gross N transformations are distinctively different among ADE and Adjacent sites, providing a strong indication how the dynamics of the individual N transformation rates have been affected by the long-term management. References cited Müller et al. (2004) A 15N tracing model to analyse N-transformations in old grassland soil. SBB 36:619-632. Müller et al. (2007) Estimation of parameters in complex 15N tracing models by Monte Carlo sampling. SBB 39:715-726.
Amazonian foods and implications for human biology.
Dufour, Darna L; Piperata, Barbara A; Murrieta, Rui S S; Wilson, Warren M; Williams, Drake D
2016-07-01
Diets of subsistence-based Amazonian populations have been linked to local resources, but are changing with market penetration. To review the available data on traditional Amazonian foods and diets and evaluate their implications for human biology as a step toward understanding nutrition transitions in the region. This study used the Human Relations Area Files for information on the diets of Amerindian groups in the Amazon Basin from 1950 to the present, and used other published sources and the authors' own data. Data on food use was identified for only nine groups and dietary intake data for individuals in only three of the groups. A diet based on starchy staples (manioc and plantains) and fish, supplemented with a limited variety of other plant and animal foods, was found. Bitter manioc-based foods were associated with the consumption of cyanogens and fish with the consumption of mercury. Diets of adults appear to be adequate in energy and protein and low in fats. Children's diets were not well documented. Based on the limited available data, Amazonian diets are restricted in variety, but appear to be adequate in energy and protein for adults, but likely insufficiently nutrient-dense for children.
40K/137Cs discrimination ratios to the aboveground organs of tropical plants.
Sanches, N; Anjos, R M; Mosquera, B
2008-07-01
In the present work, the accumulation of caesium and potassium in aboveground plant parts was studied in order to improve the understanding on the behaviour of monovalent cations in several compartments of tropical plants. We present the results for activity concentrations of (137)Cs and (40)K, measured by gamma spectrometry, from five tropical plant species: guava (Psidium guajava), mango (Mangifera indica), papaya (Carica papaya), banana (Musa paradisíaca), and manioc (Manihot esculenta). Caesium and potassium have shown a high level of mobility within the plants, exhibiting the highest values of concentration in the growing parts (fruits, leaves, twigs, and barks) of the woody fruit and large herbaceous shrub (such as manioc) species. In contrast, the banana and papaya plants exhibited the lowest levels of (137)Cs and (40)K in their growing parts. However, a significant correlation between activity concentrations of (137)Cs and (40)K was observed in these tropical plants. The (40)K/(137)Cs discrimination ratios were approximately equal to unity in different compartments of each individual plant, suggesting the possibility of using caesium to predict the behaviour of potassium in several tropical species.
Henman, A R
1982-11-01
Guaraná is considered an ideal crop for supplementing the incomes of small peasant farmers in the Amazon basin. A fast-growing perennial, guaraná can be planted in the midst of manioc crops, allowing the formation of extensive orchards in the place of regenerating scrub once the manioc has been harvested. Traditional forms of guaraná agriculture practised by the Saterê-Mawé Indians compare favourably with the plantation system favoured by government agronomists. Indigenous techniques of hand-processing guaraná are also shown to produce better quality in the finished product than those practices adopted by industrial concerns. A detailed comparison of two systems of production show the Indians' implicit concern to avoid oxidization of the phenolic compounds in the seed, since this leads to the guaraná becoming dark in colour, bitter in taste, and irritating to the gastrointestinal tract. The short-term medicinal effects of guaraná are commonly thought to result from a high content of caffeine and associated alkaloids, as well as from considerable amounts of tannin. Future research may well show that various saponins also play an important part in the drug's pharmacology, particularly with regard to its long-term influence as a general tonic and prophylactic.
NASA Technical Reports Server (NTRS)
Romanoff, Steven
1991-01-01
Cross-cultural, village-level, and farmer surveys have been used with a geographical information system to describe the distribution and relative importance of cassava (manioc, yuca, Manihot esculenta) in its cultural, economic, and ecological contexts. It presents examples of data management for mapping, sample selection, cross-tabulation of characteristics, combination of data types for indices and hypothesis testing. The methods used are reviewed, and some of the main conclusions of the study are presented.
Do Sri Lankan meals help decrease blood glucose response?
Hettiaratchi, U P K; Ekanayake, S; Welihinda, J
2009-06-01
The prevalence of diabetes mellitus (DM) has rapidly increased in Asian countries including Sri Lanka during the past decade. Scientific data on postprandial glycaemic influence of common meals is essential when formulating diets. Objectives of this study were to analyse glycaemic indices (GI) of five common meals and effects of macronutrients, sources of carbohydrates, and physicochemical properties of starch on observed GI values. The meals analysed were; 1 - red rice (AT 353) meal, 2 - red rice mixed meal, 3 - stringhopper (wheat flour) meal, 4 - stringhopper (rice flour) meal, 5 - manioc (Manihot esculenta) meal. University of Sri Jayewardenepura. Healthy individuals (n=10; age: 20-30 years). GI of each meal was calculated according to FAO/WHO guidelines by taking the ratio of incremental area under blood glucose curve (IAUC) of test and the standard. GI of meals 1-5 were 99 +/- 10, 60 +/- 5, 104 +/- 7, 102 +/- 11 and 120 +/- 9 respectively. The glycaemic response to rice mixed meal was significantly lower (p<0.05) than the others. The total dietary fibre content showed a significant negative correlation (p=0.044) with the GI value while the protein showed a non-significant negative relationship (p>0.05). Red rice had a combination of intact, swollen and disintegrated starch granules while string hoppers and manioc showed only the latter two types. The rice mixed meal has the lowest glycaemic index. Presence of dietary fibre and a legume reduces the glycaemic response. Cooking may change the glycaemic response of certain food.
Gourd and squash artifacts yield starch grains of feasting foods from preceramic Peru
Duncan, Neil A.; Pearsall, Deborah M.; Benfer, Robert A.
2009-01-01
In a study of residues from gourd and squash artifacts, we recovered starch grains from manioc (Manihot esculenta), potato (Solanum sp.), chili pepper (Capsicum spp.), arrowroot (Maranta arundinacea), and algarrobo (Prosopis sp.) from feasting contexts at the Buena Vista site, a central Peruvian preceramic site dating to ≈2200 calendar years B.C. This study has implications for the study of plant food use wherever gourds or squashes are preserved, documents the earliest evidence for the consumption of algarrobo and arrowroot in Peru, and provides insights into foods consumed at feasts. PMID:19633184
Tucker, Bram
2007-09-01
Governments and non-govermental organizations (NGOs) that plan projects to conserve the environment and alleviate poverty often attempt to modify rural livelihoods by halting activities they judge to be destructive or inefficient and encouraging alternatives. Project planners typically do so without understanding how rural people themselves judge the value of their activities. When the alternatives planners recommend do not replace the value of banned activities, alternatives are unlikely to be adopted, and local people will refuse to participate. Human behavioral ecology and behavioral economics may provide useful tools for generating and evaluating hypotheses for how people value economic activities in their portfolios and potential alternatives. This is demonstrated with a case example from southwestern Madagascar, where plans to create a Mikea Forest National Park began with the elimination of slash-and-burn maize agriculture and the encouragement to plant labor-intensive manioc instead. Future park plans could restrict access to wild tuber patches, hunting small game, and fishing. The value of these activities is considered using observational data informed by optimal foraging theory, and experimental data describing people's time preference and covariation perception. Analyses suggest that manioc is not a suitable replacement for maize for many Mikea because the two crops differ in terms of labor requirements, delay-to-reward, and covariation with rainfall. Park planners should promote wild tuber foraging and stewardship of tuber patches and the anthropogenic landscapes in which they are found. To conserve small game, planners must provide alternative sources of protein and cash. Little effort should be spent protecting lemurs, as they are rarely eaten and never sold.
The Chemistry of Diet: Medicine, Nutrition, and Staple Foods in Imperial Brazil.
Loureiro de Mendonça Couto, Cristiana
2015-01-01
Brazilian cuisine is much admired by present-day international chefs. However, in the nineteenth century, local ingredients and recipes were looked down upon by the Portuguese colonists, as well as by visiting European naturalists. This fact, together with medical and chemical views formulated throughout the 1800s, led locally trained doctors to attribute the occurrence of countless diseases that devastated Rio de Janeiro to local staple foods, particularly corn and manioc flour. In the first part of the present article, I review the dietary habits of Brazilians through the eyes of European naturalists who travelled across the country in the early nineteenth century. In the second part, I summarise the ideas formulated by French and German chemists on the components, and consequent nutritional value, of cereals and other sources of flour, and then analyse the appropriation of such ideas--particularly those of Justus Liebig--by Brazilian doctors and their adaptation to local conditions.
Dynamical Structure of a Traditional Amazonian Social Network
Hooper, Paul L.; DeDeo, Simon; Caldwell Hooper, Ann E.; Gurven, Michael; Kaplan, Hillard S.
2014-01-01
Reciprocity is a vital feature of social networks, but relatively little is known about its temporal structure or the mechanisms underlying its persistence in real world behavior. In pursuit of these two questions, we study the stationary and dynamical signals of reciprocity in a network of manioc beer (Spanish: chicha; Tsimane’: shocdye’) drinking events in a Tsimane’ village in lowland Bolivia. At the stationary level, our analysis reveals that social exchange within the community is heterogeneously patterned according to kinship and spatial proximity. A positive relationship between the frequencies at which two families host each other, controlling for kinship and proximity, provides evidence for stationary reciprocity. Our analysis of the dynamical structure of this network presents a novel method for the study of conditional, or non-stationary, reciprocity effects. We find evidence that short-timescale reciprocity (within three days) is present among non- and distant-kin pairs; conversely, we find that levels of cooperation among close kin can be accounted for on the stationary hypothesis alone. PMID:25053880
Histopathological changes in rat pancreas after fasting and cassava feeding.
Geldof, A A; Becking, J L; de Vries, C D; van der Veen, E A
1992-01-01
Histopathological changes in rat pancreas were induced by cyclic periods of experimental malnutrition or by cassava (manioc) feeding for 11 weeks. Decline of body weight was correlated with decrease in testicular fat pad weight as a measure of body fat stores. A marked decrease in pancreatic weight in the cassava-fed group was correlated with shrinkage of acinar structures and degenerative features in exocrine pancreas. In the malnutrition group vacuolisation and loss of tissue architecture were observed in some parts of the organ. No signs of ductal obstruction as a tentative cause of pancreatic pathology after malnutrition could be detected. Loss of islets tissue was occasionally seen in degenerative areas. It is concluded that histopathological changes in exocrine pancreas result from malnutrition and cassava feeding differentially and precede ultimate degenerative processes of pancreas endocrine tissue. Tropical malnutrition type diabetes and low protein related diabetes may in their etiology be different entities, but may coincide in practice and aggravate each other to yield severe and irreversible morbidity.
Starch grains reveal early root crop horticulture in the Panamanian tropical forest.
Piperno, D R; Ranere, A J; Holst, I; Hansell, P
2000-10-19
Native American populations are known to have cultivated a large number of plants and domesticated them for their starch-rich underground organs. Suggestions that the likely source of many of these crops, the tropical forest, was an early and influential centre of plant husbandry have long been controversial because the organic remains of roots and tubers are poorly preserved in archaeological sediments from the humid tropics. Here we report the occurrence of starch grains identifiable as manioc (Manihot esculenta Crantz), yams (Dioscorea sp.) and arrowroot (Maranta arundinacea L.) on assemblages of plant milling stones from preceramic horizons at the Aguadulce Shelter, Panama, dated between 7,000 and 5,000 years before present (BP). The artefacts also contain maize starch (Zea mays L.), indicating that early horticultural systems in this region were mixtures of root and seed crops. The data provide the earliest direct evidence for root crop cultivation in the Americas, and support an ancient and independent emergence of plant domestication in the lowland Neotropical forest.
Dynamical Structure of a Traditional Amazonian Social Network.
Hooper, Paul L; DeDeo, Simon; Caldwell Hooper, Ann E; Gurven, Michael; Kaplan, Hillard S
2013-11-13
Reciprocity is a vital feature of social networks, but relatively little is known about its temporal structure or the mechanisms underlying its persistence in real world behavior. In pursuit of these two questions, we study the stationary and dynamical signals of reciprocity in a network of manioc beer (Spanish: chicha ; Tsimane': shocdye' ) drinking events in a Tsimane' village in lowland Bolivia. At the stationary level, our analysis reveals that social exchange within the community is heterogeneously patterned according to kinship and spatial proximity. A positive relationship between the frequencies at which two families host each other, controlling for kinship and proximity, provides evidence for stationary reciprocity. Our analysis of the dynamical structure of this network presents a novel method for the study of conditional, or non-stationary, reciprocity effects. We find evidence that short-timescale reciprocity (within three days) is present among non- and distant-kin pairs; conversely, we find that levels of cooperation among close kin can be accounted for on the stationary hypothesis alone.
Peña-Venegas, C P; Stomph, T J; Verschoor, G; Echeverri, J A; Struik, P C
Outsiders often oversimplify Amazon soil use by assuming that abundantly available natural soils are poorly suited to agriculture and that sporadic anthropogenic soils are agriculturally productive. Local perceptions about the potentials and limitations of soils probably differ, but information on these perceptions is scarce. We therefore examined how four indigenous communities in the Middle Caquetá River region in the Colombian Amazon classify and use natural and anthropogenic soils. The study was framed in ethnopedology: local classifications, preferences, rankings, and soil uses were recorded through interviews and field observations. These communities recognized nine soils varying in suitability for agriculture. They identified anthropogenic soils as most suitable for agriculture, but only one group used them predominantly for their swiddens. As these communities did not perceive soil nutrient status as limiting, they did not base crop-site selection on soil fertility or on the interplay between soil quality and performance of manioc genetic resources.
Carvalho, Edilaine Oliveira; da Rocha, Emersom Ferreira
2011-01-01
It is a transverse study where a questionnaire of alimentary frequency was applied (QAF) in 150 adults resident of the rural area of the city of Ibatiba (ES, Brazil). QAF classified the alimentary consumption as: habitual (>4 times in the week), not habitual (<4 times in the week) and rarely (1 time a month), with objective of correlating the alimentary consumption with the chronic-degenerative diseases. The results evidenced a habitual consumption of rice, breads, stalk, bean, cow milk, animal fat, margarine, sugar and coffee, and a non habitual consumption of cake, potato, cookies, manioc, sweet potato, chayote, carrot, beet, pumpkin, juice of fruits, banana, orange, guava, mango and tangerine. It can be concluded that the feeding habit presented by the studied population it can come to increase in a medium or long period the prevalence and occurrences of chronic-degenerative diseases as hypertension, diabetes, obesity and coronary diseases. The alimentary consumption of this population needs concern, because when compared with the national patterns, it is observed some inadequacies, and it is known that this picture comes to every day causing damages the public health.
Mediate gamma radiation effects on some packaged food items
NASA Astrophysics Data System (ADS)
Inamura, Patricia Y.; Uehara, Vanessa B.; Teixeira, Christian A. H. M.; del Mastro, Nelida L.
2012-08-01
For most of prepackaged foods a 10 kGy radiation dose is considered the maximum dose needed; however, the commercially available and practically accepted packaging materials must be suitable for such application. This work describes the application of ionizing radiation on several packaged food items, using 5 dehydrated food items, 5 ready-to-eat meals and 5 ready-to-eat food items irradiated in a 60Co gamma source with a 3 kGy dose. The quality evaluation of the irradiated samples was performed 2 and 8 months after irradiation. Microbiological analysis (bacteria, fungus and yeast load) was performed. The sensory characteristics were established for appearance, aroma, texture and flavor attributes were also established. From these data, the acceptability of all irradiated items was obtained. All ready-to-eat food items assayed like manioc flour, some pâtés and blocks of raw brown sugar and most of ready-to-eat meals like sausages and chicken with legumes were considered acceptable for microbial and sensory characteristics. On the other hand, the dehydrated food items chosen for this study, such as dehydrated bacon potatoes or pea soups were not accepted by the sensory analysis. A careful dose choice and special irradiation conditions must be used in order to achieve sensory acceptability needed for the commercialization of specific irradiated food items.
Gayo, Eugenia M.; Santoro, Calogero M.; De Pol-Holz, Ricardo; Latorre, Claudio
2017-01-01
Archaeological and palaeoecological studies throughout the Americas have documented widespread landscape and environmental transformation during the pre-Columbian era. The highly dynamic Formative (or Neolithic) period in northern Chile (ca. 3700–1550 yr BP) brought about the local establishment of agriculture, introduction of new crops (maize, quinoa, manioc, beans, etc.) along with a major population increase, new emergent villages and technological innovations. Even trees such as the Algarrobos (Prosopis section Algarobia) may have been part of this transformation. Here, we provide evidence that these species were not native to the Atacama Desert of Chile (18–27°S), appearing only in the late Holocene and most likely due to human actions. We assembled a database composed of 41 taxon specific AMS radiocarbon dates from archaeobotanical and palaeoecological records (rodent middens, leaf litter deposits), as well an extensive bibliographical review comprising archaeobotanical, paleoecological, phylogenetic and taxonomic data to evaluate the chronology of introduction and dispersal of these trees. Although Algarrobos could have appeared as early as 4200 yr BP in northernmost Chile, they only became common throughout the Atacama over a thousand years later, during and after the Formative period. Cultural and natural factors likely contributed to its spread and consolidation as a major silvicultural resource. PMID:28742126
Dickau, Ruth; Ranere, Anthony J; Cooke, Richard G
2007-02-27
The Central American isthmus was a major dispersal route for plant taxa originally brought under cultivation in the domestication centers of southern Mexico and northern South America. Recently developed methodologies in the archaeological and biological sciences are providing increasing amounts of data regarding the timing and nature of these dispersals and the associated transition to food production in various regions. One of these methodologies, starch grain analysis, recovers identifiable microfossils of economic plants directly off the stone tools used to process them. We report on new starch grain evidence from Panama demonstrating the early spread of three important New World cultigens: maize (Zea mays), manioc (Manihot esculenta), and arrowroot (Maranta arundinacea). Maize starch recovered from stone tools at a site located in the Pacific lowlands of central Panama confirms previous archaeobotanical evidence for the use of maize there by 7800-7000 cal BP. Starch evidence from preceramic sites in the less seasonal, humid premontane forests of Chiriquí province, western Panama, shows that maize and root crops were present by 7400-5600 cal BP, several millennia earlier than previously documented. Several local starchy resources, including Zamia and Dioscorea spp., were also used. The data from both regions suggest that crop dispersals took place via diffusion or exchange of plant germplasm rather than movement of human populations practicing agriculture.
Carod-Artal, F J
A wide range of plants, seeds and fruits used for nutritional and medicinal purposes can give rise to neurotoxic symptoms. We review the neurological pathology associated with the acute or chronic consumption of plants, seeds and fruits in human beings and in animals. Of the plants that can trigger acute neurotoxic syndromes in humans, some of the most notable include Mandragora officinalis, Datura stramonium, Conium maculatum (hemlock), Coriaria myrtifolia (redoul), Ricinus communis, Gloriosa superba, Catharanthus roseus, Karwinskia humboldtiana and Podophyllum pelatum. We also survey different neurological syndromes linked with the ingestion of vegetable foodstuffs that are rich in cyanogenic glycosides, Jamaican vomiting sickness caused by Blighia sapida, Parkinson dementia ALS of Guam island and exposition to Cycas circinalis, Guadeloupean parkinsonism and exposition to Annonaceae, konzo caused by ingestion of wild manioc and neurolathyrism from ingestion of Lathyrus sativus, the last two being models of motor neurone disease. Locoism is a chronic disease that develops in livestock feeding on plants belonging to Astragalus and Oxytropis sp., Sida carpinifolia and Ipomea carnea, which are rich in swainsonine, a toxin that inhibits the enzyme alpha mannosidase and induces a cerebellar syndrome. The ingestion of neurotoxic seeds, fruits and plants included in the diet and acute poisoning by certain plants can give rise to different neurological syndromes, some of which are irreversible.
Dickau, Ruth; Ranere, Anthony J.; Cooke, Richard G.
2007-01-01
The Central American isthmus was a major dispersal route for plant taxa originally brought under cultivation in the domestication centers of southern Mexico and northern South America. Recently developed methodologies in the archaeological and biological sciences are providing increasing amounts of data regarding the timing and nature of these dispersals and the associated transition to food production in various regions. One of these methodologies, starch grain analysis, recovers identifiable microfossils of economic plants directly off the stone tools used to process them. We report on new starch grain evidence from Panama demonstrating the early spread of three important New World cultigens: maize (Zea mays), manioc (Manihot esculenta), and arrowroot (Maranta arundinacea). Maize starch recovered from stone tools at a site located in the Pacific lowlands of central Panama confirms previous archaeobotanical evidence for the use of maize there by 7800–7000 cal BP. Starch evidence from preceramic sites in the less seasonal, humid premontane forests of Chiriquí province, western Panama, shows that maize and root crops were present by 7400–5600 cal BP, several millennia earlier than previously documented. Several local starchy resources, including Zamia and Dioscorea spp., were also used. The data from both regions suggest that crop dispersals took place via diffusion or exchange of plant germplasm rather than movement of human populations practicing agriculture. PMID:17360697
Earth Observations taken by the Expedition 16 Crew
2007-11-22
ISS016-E-011999 (22 Nov. 2007) --- Sao Simao Reservoir, Brazil is featured in this image photographed by an Expedition 16 crewmember on the International Space Station (ISS). The Sao Simao reservoir, near the confluence of the Rio Paranaiba and Rio Verde in Brazil, is the featured subject in a milestone image of Earth. This colorful, patchwork image is the 300,000th image of Earth downlinked from the space station. There are now over 745,000 images of Earth taken by astronaut crews, beginning with the Mercury missions in 1961 and continuing to the present day on the ISS. The Sao Simao reservoir is located on the border between the states of Goias and Minas Gerais (near the geographic coordinates of 18.7S 50.4W). Though the town of Sao Simao was founded around 1935, major growth occurred when the hydroelectric power plant and dam were built - forming the reservoir -- in 1975. The reservoir is part of a major navigation link that allows transport of goods and commerce between central Brazil, the Prata River and the South Atlantic. With 600,000 square kilometers of surface area, the reservoir also serves as a tourist destination for fishing, swimming and boating. In addition to hydroelectric power production, the economy of the region is based in agribusiness. The image highlights agricultural fields of various kinds and in different stages of cultivation. The major commodities include corn, soybeans, sesame seeds, sugarcane, beans, manioc, coffee and meat production.
NASA Astrophysics Data System (ADS)
Giordano, Raquel L. C.; Trovati, Joubert; Schmidell, Willibaldo
This work presents a continuous simultaneous saccharification and fermentation (SSF) process to produce ethanol from starch using glucoamylase and Saccharomyces cerevisiae co-immobilized in pectin gel. The enzyme was immobilized on macroporous silica, after silanization and activation of the support with glutaraldehyde. The silicaenzyme derivative was co-immobilized with yeast in pectin gel. This biocatalyst was used to produce ethanol from liquefied manioc root flour syrup, in three fixed bed reactors. The initial reactor yeast load was 0.05 g wet yeast/ml of reactor (0.1 g wet yeast/g gel), used in all SSF experiments. The enzyme concentration in the reactor was defined by running SSF batch assays, using different amount of silica-enzyme derivative, co-immobilized with yeast in pectin gel. The chosen reactor enzyme concentration, 3.77 U/ml, allowed fermentation to be the rate-limiting step in the batch experiment. In this condition, using initial substrate concentration of 166.0 g/1 of total reducing sugars (TRS), 1 ml gel/1 ml of medium, ethanol productivity of 8.3 g/l/h was achieved, for total conversion of starch to ethanol and 91% of the theoretical yield. In the continuous runs, feeding 163.0 g/1 of TRS and using the same enzyme and yeast concentrations used in the batch run, ethanol productivity was 5.9 g ethanol/1/h, with 97% of substrate conversion and 81% of the ethanol theoretical yield. Diffusion effects in the extra-biocatalyst film seemed to be reduced when operating at superficial velocities above 3.7 × 10-4 cm/s.
McKey, Doyle; Rostain, Stéphen; Iriarte, José; Glaser, Bruno; Birk, Jago Jonathan; Holst, Irene; Renard, Delphine
2010-04-27
The scale and nature of pre-Columbian human impacts in Amazonia are currently hotly debated. Whereas pre-Columbian people dramatically changed the distribution and abundance of species and habitats in some parts of Amazonia, their impact in other parts is less clear. Pioneer research asked whether their effects reached even further, changing how ecosystems function, but few in-depth studies have examined mechanisms underpinning the resilience of these modifications. Combining archeology, archeobotany, paleoecology, soil science, ecology, and aerial imagery, we show that pre-Columbian farmers of the Guianas coast constructed large raised-field complexes, growing on them crops including maize, manioc, and squash. Farmers created physical and biogeochemical heterogeneity in flat, marshy environments by constructing raised fields. When these fields were later abandoned, the mosaic of well-drained islands in the flooded matrix set in motion self-organizing processes driven by ecosystem engineers (ants, termites, earthworms, and woody plants) that occur preferentially on abandoned raised fields. Today, feedbacks generated by these ecosystem engineers maintain the human-initiated concentration of resources in these structures. Engineer organisms transport materials to abandoned raised fields and modify the structure and composition of their soils, reducing erodibility. The profound alteration of ecosystem functioning in these landscapes coconstructed by humans and nature has important implications for understanding Amazonian history and biodiversity. Furthermore, these landscapes show how sustainability of food-production systems can be enhanced by engineering into them follows that maintain ecosystem services and biodiversity. Like anthropogenic dark earths in forested Amazonia, these self-organizing ecosystems illustrate the ecological complexity of the legacy of pre-Columbian land use.
Giordano, Raquel L C; Trovati, Joubert; Schmidell, Willibaldo
2008-03-01
This work presents a continuous simultaneous saccharification and fermentation (SSF) process to produce ethanol from starch using glucoamylase and Saccharomyces cerevisiae co-immobilized in pectin gel. The enzyme was immobilized on macroporous silica, after silanization and activation of the support with glutaraldehyde. The silica-enzyme derivative was co-immobilized with yeast in pectin gel. This biocatalyst was used to produce ethanol from liquefied manioc root flour syrup, in three fixed bed reactors. The initial reactor yeast load was 0.05 g wet yeast/ml of reactor (0.1 g wet yeast/g gel), used in all SSF experiments. The enzyme concentration in the reactor was defined by running SSF batch assays, using different amount of silica-enzyme derivative, co-immobilized with yeast in pectin gel. The chosen reactor enzyme concentration, 3.77 U/ml, allowed fermentation to be the rate-limiting step in the batch experiment. In this condition, using initial substrate concentration of 166.0 g/l of total reducing sugars (TRS), 1 ml gel/1 ml of medium, ethanol productivity of 8.3 g/l/h was achieved, for total conversion of starch to ethanol and 91% of the theoretical yield. In the continuous runs, feeding 163.0 g/l of TRS and using the same enzyme and yeast concentrations used in the batch run, ethanol productivity was 5.9 g ethanol/l/h, with 97% of substrate conversion and 81% of the ethanol theoretical yield. Diffusion effects in the extra-biocatalyst film seemed to be reduced when operating at superficial velocities above 3.7 x 10(-4) cm/s.
McKey, Doyle; Rostain, Stéphen; Iriarte, José; Glaser, Bruno; Birk, Jago Jonathan; Holst, Irene; Renard, Delphine
2010-01-01
The scale and nature of pre-Columbian human impacts in Amazonia are currently hotly debated. Whereas pre-Columbian people dramatically changed the distribution and abundance of species and habitats in some parts of Amazonia, their impact in other parts is less clear. Pioneer research asked whether their effects reached even further, changing how ecosystems function, but few in-depth studies have examined mechanisms underpinning the resilience of these modifications. Combining archeology, archeobotany, paleoecology, soil science, ecology, and aerial imagery, we show that pre-Columbian farmers of the Guianas coast constructed large raised-field complexes, growing on them crops including maize, manioc, and squash. Farmers created physical and biogeochemical heterogeneity in flat, marshy environments by constructing raised fields. When these fields were later abandoned, the mosaic of well-drained islands in the flooded matrix set in motion self-organizing processes driven by ecosystem engineers (ants, termites, earthworms, and woody plants) that occur preferentially on abandoned raised fields. Today, feedbacks generated by these ecosystem engineers maintain the human-initiated concentration of resources in these structures. Engineer organisms transport materials to abandoned raised fields and modify the structure and composition of their soils, reducing erodibility. The profound alteration of ecosystem functioning in these landscapes coconstructed by humans and nature has important implications for understanding Amazonian history and biodiversity. Furthermore, these landscapes show how sustainability of food-production systems can be enhanced by engineering into them fallows that maintain ecosystem services and biodiversity. Like anthropogenic dark earths in forested Amazonia, these self-organizing ecosystems illustrate the ecological complexity of the legacy of pre-Columbian land use. PMID:20385814
Piperata, Barbara A; Ivanova, Sofia A; Da-gloria, Pedro; Veiga, Gonçalo; Polsky, Analise; Spence, Jennifer E; Murrieta, Rui S S
2011-01-01
The goal of this study was to understand the relationship between economic change (wage labor, retirement, and the Bolsa Família program) and dietary patterns in the rural Amazon and to determine the extent to which these changes followed the pattern of the nutrition transition. The study was longitudinal. The weighed-inventory method and economic interviews were used to collect data on dietary intake and household economics in a sample of 30 and 52 women in 2002 and 2009, respectively. Twenty of the women participated in both years and make-up the longitudinal sub-sample. Comparative statistics were used to identify changes in dietary patterns over time and multiple linear regressions were used to explore the relationship between economics, subsistence strategies, and diet. There was a significant decline in kcal (P < 0.01) and carbohydrate (P < 0.01) but no change in protein intake over time in both the larger and smaller, longitudinal subsample. The percent of energy, carbohydrate, protein, and fat purchased increased in the larger and longitudinal samples (P ≤ 0.02) and there was an increase in refined carbohydrate and processed, fatty-meat consumption over time. The abandonment of manioc gardens was associated with increased dependence on purchased food (P = 0.03) while receipt of the Bolsa Família was associated with increased protein intake and adequacy (P = 0.02). The dietary changes observed are only in partial agreement with predictions of the nutrition transition literature. The relationship between the economic and diet changes was shaped by the local context which should be considered when implementing CCT programs, like the Bolsa Família. Copyright © 2011 Wiley-Liss, Inc.
Assessment of Bacterial bph Gene in Amazonian Dark Earth and Their Adjacent Soils
Brossi, Maria Julia de Lima; Mendes, Lucas William; Germano, Mariana Gomes; Lima, Amanda Barbosa; Tsai, Siu Mui
2014-01-01
Amazonian Anthrosols are known to harbour distinct and highly diverse microbial communities. As most of the current assessments of these communities are based on taxonomic profiles, the functional gene structure of these communities, such as those responsible for key steps in the carbon cycle, mostly remain elusive. To gain insights into the diversity of catabolic genes involved in the degradation of hydrocarbons in anthropogenic horizons, we analysed the bacterial bph gene community structure, composition and abundance using T-RFLP, 454-pyrosequencing and quantitative PCR essays, respectively. Soil samples were collected in two Brazilian Amazon Dark Earth (ADE) sites and at their corresponding non-anthropogenic adjacent soils (ADJ), under two different land use systems, secondary forest (SF) and manioc cultivation (M). Redundancy analysis of T-RFLP data revealed differences in bph gene structure according to both soil type and land use. Chemical properties of ADE soils, such as high organic carbon and organic matter, as well as effective cation exchange capacity and pH, were significantly correlated with the structure of bph communities. Also, the taxonomic affiliation of bph gene sequences revealed the segregation of community composition according to the soil type. Sequences at ADE sites were mostly affiliated to aromatic hydrocarbon degraders belonging to the genera Streptomyces, Sphingomonas, Rhodococcus, Mycobacterium, Conexibacter and Burkholderia. In both land use sites, shannon's diversity indices based on the bph gene data were higher in ADE than ADJ soils. Collectively, our findings provide evidence that specific properties in ADE soils shape the structure and composition of bph communities. These results provide a basis for further investigations focusing on the bio-exploration of novel enzymes with potential use in the biotechnology/biodegradation industry. PMID:24927167
Assessment of bacterial bph gene in Amazonian dark earth and their adjacent soils.
Brossi, Maria Julia de Lima; Mendes, Lucas William; Germano, Mariana Gomes; Lima, Amanda Barbosa; Tsai, Siu Mui
2014-01-01
Amazonian Anthrosols are known to harbour distinct and highly diverse microbial communities. As most of the current assessments of these communities are based on taxonomic profiles, the functional gene structure of these communities, such as those responsible for key steps in the carbon cycle, mostly remain elusive. To gain insights into the diversity of catabolic genes involved in the degradation of hydrocarbons in anthropogenic horizons, we analysed the bacterial bph gene community structure, composition and abundance using T-RFLP, 454-pyrosequencing and quantitative PCR essays, respectively. Soil samples were collected in two Brazilian Amazon Dark Earth (ADE) sites and at their corresponding non-anthropogenic adjacent soils (ADJ), under two different land use systems, secondary forest (SF) and manioc cultivation (M). Redundancy analysis of T-RFLP data revealed differences in bph gene structure according to both soil type and land use. Chemical properties of ADE soils, such as high organic carbon and organic matter, as well as effective cation exchange capacity and pH, were significantly correlated with the structure of bph communities. Also, the taxonomic affiliation of bph gene sequences revealed the segregation of community composition according to the soil type. Sequences at ADE sites were mostly affiliated to aromatic hydrocarbon degraders belonging to the genera Streptomyces, Sphingomonas, Rhodococcus, Mycobacterium, Conexibacter and Burkholderia. In both land use sites, shannon's diversity indices based on the bph gene data were higher in ADE than ADJ soils. Collectively, our findings provide evidence that specific properties in ADE soils shape the structure and composition of bph communities. These results provide a basis for further investigations focusing on the bio-exploration of novel enzymes with potential use in the biotechnology/biodegradation industry.
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.
Bentley, G R; Harrigan, A M; Ellison, P T
1998-04-01
To assess dietary composition in relation to energetic status and ovarian function. An eight-month prospective study undertaken in 1989. Ituri Forest, northeast Democratic Republic of Congo. Sixty-four female volunteers of reproductive age (16-45), with a subsample of 30 for nutritional focal follows, 39 for analysis of salivary progesterone levels, and 18 for analysis of salivary oestradiol. Regular anthropometric measurements of heights, weights, and mid-triceps skinfolds, 204 h of nutritional focal follows when all foods prepared and consumed were recorded and weighed, analysis of dietary composition using African food tables, collection of saliva samples every-other day for radioimmunoassay of salivary oestradiol and progesterone. The primary staple in the Lese diet is manioc, consumed at nearly every meal, but the diet is subject to seasonal fluctuations. Important seasonal crops are groundnuts and rice. Carbohydrates comprise 64% of the diet, protein 14% and fat 22%, but seasonal fluctuations in food items create significant differences in protein content (P = 0.007). Energy intake falls by 25% in the hunger season. Lese energy balance reflects this lack with women losing a mean 7% of total body weight. The mean BMI for Lese women at the beginning of the study was 22.8 but, during the hunger season, the BMI for 20% of women fell to < 18.5, indicative of chronic energy shortage. Mean levels of Lese salivary oestradiol and progesterone are chronically and significantly lower than healthy, Western controls (P = 0.0001 for progesterone; P = 0.03 for follicular values of oestradiol, P = 0.0001 for mid-cycle values, and P = 0.0002 for luteal values). Mean salivary progesterone levels were significantly lower for those Lese women losing weight (P = 0.03), and significantly lower for weight-loss women when comparing levels at the beginning and end of the hunger season (P = 0.03). The relatively low-fat, high-fibre diet of the Lese appears healthy, but there are occasional seasonal deficiencies in protein-energy and micronutrient content, especially for pregnant and lactating women. Dietary composition may affect Lese levels of reproductive steroids, partly explaining the chronically low salivary oestradiol profile of this population.
What is a population? Spouse import in the northwest Amazon.
Chernela, J M
1994-03-01
In northwest Amazon societies, diverse groups marry across linguistic and geographic barriers: kinship and kin proximity occur according to cultural rules, and kinship, language, and residence may not be equated with genetic relatedness, as previously postulated. The assumption of genetic relatedness and random mating within a prescribed geographic zone or linguistic unit does not always hold true. Models should be based on cultural determinants of population dynamics that are more sensitive to detailed mate choice and gene flow patterns. The example is given of the Wanano, who belong to the Eastern Tukanoan Language group in the Central Northwest Amazon basin of the Uaupes River; 500-600 lived in Brazil, 180 Colombia, and 800 in the Vaupes Territory of Colombia. Settlements were 3-24 km from the river and had a population of 17-160 people. Men pursued fishing and women engaged in manioc cultivation. There was minimal exploitation of resources. The Wanano are unilineal kin groups with cross cousin marriages. They share a common cultural heritage with 15-20 other kin groups, and are linked through intermarriage. 14,000 Indians of diverse languages are thus united in marriage and kinship. Neighboring Arawakan and Cariban speaking groups reside to the north and west. About 13 distinct languages are part of the Eastern Tukanoan language. The basic principles of descent, marriage, and residence were supplied, and the consequences for village composition explicated. Focus was placed on 3 Wanano villages (Yapima; Mo, a large village with in-marrying from the village of Buhpoara; and Buhpoara) and spouse importation. Social organization was on the basis of sib (patrilineal descent group), language group (common identity, language, ancestry, and group name), and phratry, or nonresidential association of language groups. Ties were strong among more intimate or a"in-groups." Marriage rules applied to preferences for patrilineal cross cousins and sister exchange. The villages described exemplified the imbalances in the sex ratio and the bachelor surplus in the smaller Wanano villages. The result has been the practice of patrilocality and linguistic exogamy, where adult males of the same ethnicity live together and adult females are located through marriage.
Prevedello, Jayme Augusto; Forero-Medina, Germán; Vieira, Marcus Vinícius
2010-11-01
1. For animal species inhabiting heterogeneous landscapes, the tortuosity of the dispersal path is a key determinant of the success in locating habitat patches. Path tortuosity within and beyond perceptual range must differ, and may be differently affected by intrinsic attributes of individuals and extrinsic environmental factors. Understanding how these factors interact to determine path tortuosity allows more accurate inference of successful movements between habitat patches. 2. We experimentally determined the effects of intrinsic (body mass and species identity) and extrinsic factors (distance to nearest forest fragment and matrix type) on the tortuosity of movements of three forest-dwelling didelphid marsupials, in a fragmented landscape of the Atlantic Forest, Brazil. 3. A total of 202 individuals were captured in forest fragments and released in three unsuitable matrix types (mowed pasture, abandoned pasture and manioc plantation), carrying spool-and-line devices. 4. Twenty-four models were formulated representing a priori hypotheses of major determinants of path tortuosity, grouped in three scenarios (only intrinsic factors, only extrinsic factors and models with combinations of both), and compared using a model selection approach. Models were tested separately for individuals released within the perceptual range of the species, and for individuals released beyond the perceptual range. 5. Matrix type strongly affected path tortuosity, with more obstructed matrix types hampering displacement of animals. Body mass was more important than species identity to determine path tortuosity, with larger animals moving more linearly. Increased distance to the fragment resulted in more tortuous paths, but actually reflects a threshold in perceptual range: linear paths within perceptual range, tortuous paths beyond. 6. The variables tested explained successfully path tortuosity, but only for animals released within the perceptual range. Other factors, such as wind intensity and direction of plantation rows, may be more important for individuals beyond their perceptual range. 7. Simplistic scenarios considering only intrinsic or extrinsic factors are inadequate to predict path tortuosity, and to infer dispersal success in heterogeneous landscapes. Perceptual range represents a fundamental threshold where the effects of matrix type, body mass and individual behaviour change drastically. © 2010 The Authors. Journal compilation © 2010 British Ecological Society.
NASA Astrophysics Data System (ADS)
Jambert, Corinne; Pacifico, Federica; Delon, Claire; Lohou, Fabienne; Reinares Martinez, Irene; Brilouet, Pierre-Etienne; Derrien, Solene; Dione, Cheikh; Brosse, Fabien; Gabella, Omar; Pedruzzo Bagazgoitia, Xavier; Durand, Pierre
2017-04-01
Tropospheric oxidation of VOCs (Volatile Organic Compounds), including isoprene, in the presence of NOx and sunlight leads to the formation of O3 and Secondary Organic Aerosols (SOA). Changes in NO or VOCs sources will consequently modify their atmospheric concentrations and thus, the rate of O3 production and SOA formation. NOx have also an impact on the abundance of the hydroxyl radical (OH) which determines the lifetime of some pollutants and greenhouse gases. Anthropogenic emissions of pollutants from mega cities located on the Guinean coast in South West Africa are likely to increase in the next decades due to a strong anthropogenic pressure and to land use changes at the regional or continental scale. The consequences on regional air quality and on pollutant deposition onto surfaces may have some harmful effects on human and ecosystem health. Furthermore, the regional climate and water cycle are affected by changes in atmospheric chemistry. When transported northward on the African continent, polluted air masses meet biogenic emissions from rural areas which contributes to increase ozone and SOA production, in high temperature and solar radiation conditions, highly favourable to enhanced photochemistry. During the Dynamics-aerosol-chemistry-cloud interactions in West Africa (DACCIWA) field campaign, we measured the atmospheric chemical composition and the exchanges of trace components in a hinterland area of Benin, at the Savé super-site (8°02'03" N, 2°29'11″ E). The observations, monitored in June and July 2016, in a rural mixed agricultural area, include near surface concentrations of ozone (O3), carbon monoxide (CO), nitrogen oxides (NOx) and isoprene, isoprene fluxes and meteorological parameters. We observed hourly average concentrations of O3 up to 50 ppb, low NOx concentrations (ca. 1 ppb and CO concentrations between 75 and 300 ppb. An 8 m tower was equipped with a Fast Isoprene Sensor and sonic anemometer to measure isoprene concentrations and determine isoprene fluxes with eddy-covariance technique over a mixed (patched maize, manioc and anacardium) agricultural plot. We discuss the influence of meteorological conditions on biogenic emissions (i.e. isoprene fluxes) and on ambient atmospheric chemistry (i.e. isoprene, NOx, O3 and CO concentrations observed on the site). We also studied the impact of remote anthropogenic emissions from cities on the Guinean southern coast on local chemistry.
2010-01-01
Background Ethyl carbamate (EC) is a multi-site carcinogen in experimental animals and probably carcinogenic to humans (IARC group 2A). Traces of EC below health-relevant ranges naturally occur in several fermented foods and beverages, while higher concentrations above 1 mg/l are regularly detected in only certain spirits derived from cyanogenic plants. In Brazil this concerns the sugarcane spirit cachaça and the manioc (cassava) spirit tiquira, which both regularly exceed the national EC limit of 0.15 mg/l. This study aims to estimate human exposure in Brazil and provide a quantitative risk assessment. Methods The human dietary intake of EC via alcoholic beverages was estimated based on WHO alcohol consumption data in combination with own surveys and literature data. This data comprises the EC contents of the different beverage groups cachaça, tiquira, other spirits, beer, wine, and unrecorded alcohol (as defined by the WHO; including alcohol which is not captured in routine government statistics nor taxed). The risk assessment was conducted using the margin of exposure (MOE) approach with benchmark doses obtained from dose-response modelling of animal experiments. Lifetime cancer risk was calculated using the T25 dose descriptor. Results Considering differences between pot-still and column-still cachaça, its average EC content would be 0.38 mg/l. Tiquira contained a considerably higher average EC content of 2.34 mg/l. The whole population exposure from all alcoholic beverages was calculated to be around 100 to 200 ng/kg bw/day, with cachaça and unrecorded alcohol as the major contributing factors. The MOE was calculated to range between 400 and 2,466, with the lifetime cancer risk at approximately 3 cases in 10,000. An even higher risk may exist for binge-drinkers of cachaça and tiquira with MOEs of up to 80 and 15, respectively. Conclusions According to our risk assessment, EC poses a significant cancer risk for the alcohol-drinking population in Brazil, in addition to that of alcohol alone. Model calculations show that the implementation of the 0.15 mg/l limit for cachaça would be beneficial, including an increase of the MOE by a factor between 3 to 6. The implementation of policy measures for tiquira and unrecorded alcohol also appears to be advisable. PMID:20529350
Cassava biology and physiology.
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 species, pointing to the need for further research on cultivated and wild Manihot to further improve its photosynthetic potential and yield,particularly under stressful environments. Moreover, a wide range in values of Km (CO2) for the C3 photosynthetic enzyme Rubisco was found among cassava cultivars indicating the possibility of selection for higher affinity to CO2, and consequently higher leaf photosynthesis. Several plant traits that may be of value in crop breeding and improvement have been identified, such as an extensive fine root system, long leaf life, strong root sink and high leaf photosynthesis. Selection of parental materials for tolerance to drought and infertile soils under representative field conditions have resulted in developing improved cultivars that have high yields in favorable environments while producing reasonable and stable yields under stress.
[Brazil: agricultural modernisation and food production restructuring in the international crisis].
Bertrand, J P
1985-01-01
This study examines the complex relationship of capital accumulation, external debt, and food supply in Brazil, a country which has simultaneously increased its food exports and its unsatisfied demand for food imports in the context of the world economic crisis. In Brazil, the substitution of export cash crops for subsistence crops has been accompanied by a profound but incomplete restructuring of the basic food supply and model of consumption, a restructuring made possible by declining real cost of the new foods. The gap between the extremely rapid evolution of consumption, especially in the urban areas, and the possibilities of concomitant transformation of production is the characteristic feature of the change occuring in Brazil. The current diet of the developed countries evolved over a relatively long period and was based on the declining real cost of basic foodstuffs made possible by increasing labor productivity. Between 1800-1900, the real cost of a kilo of bread was halved, while that of meat remained stable. In France and the US respectively, 80 and 90% of the principal cereals are consumed by animals, while in developing countries most grains are directly consumed. Numerous indices suggest that Brazil has begun to differentiate its food regime in the direction of decreased consumption of cereals, tubers, and legumes, and increased consumption of animal products, with grains increasingly consumed indirectly by animals. Since the early 1970s, Brazil has developed a powerful processed food industry which supports intensive breeding of poultry and, to a lesser extent, pork and milk cattle. However, low income population groups have been forced to reduce their consumption of traditional foodstuffs, whose real prices have undergone relative increases, without achieving a satisfactory level of consumption of the new products. Brazilian food problems result not from insufficient production of food but from the choice of a strongly internationalist model of development in the mid-1960s which required insertion into the world economy, notably through a search for new export sectors. The agricultural sector was assigned 3 functions: producing food as cheaply as possible, increasing the proportion of exportable crops, and substituting some of the foods imported. Brazil evolved in 2 decades from a classic agroexporter to a more complex structure reflecting the semiindustrialized state of the economy. The share of processed agricultural goods increased accordingly. The foods produced for the internal market have been changing at the same time that a new hierarchy of exportable products has evolved. Agricultural policy involved recourse to market mechanisms and cheap credit focused on the south and southeastern regions, large and medium sized producers, and a few products including soy, coffee, sugar cane, and cotton. Just 3% of credits went to the traditional foodstuffs beans and manioc. The most serious consequence of the internationalization of the agricultural economy has been a dangerous increase in the vulnerability of low income groups to world food price fluctuations.
[Government policies and actions in Burundi in the area of rural development].
Mworoha, E
1986-01-01
This article discusses policies and actions designed by the government of Burundi to assure food self-sufficiency and to improve living conditions in rural areas. Burundi has had a long history of food self-sufficiency due to good soils, adequate rainfall, and hard work by the rural population. In the past 3 decades, however, the food supply has been threatened by various factors including soil erosion and rapid population increase. The government has undertaken a reforestation program which covered 51,050 hectares in the past 7 years with plans to cover 20% of the national territory by the year 2000. Work has also been done to contain rivers within their courses and to popularize antierosion techniques such as terracing and proper use of pastures. Partly because the population is growing at a rate of 2.7% per year, the average plot available per household is estimated at only 1.3 hectare, rendering efforts to improve productivity imperative. The high cost of chemical fertilizers has forced reliance on compost, and some 6 million compost heaps are now in existence. Agropastoral integration projects are seeking to improve yields through better combinations of livestock and land use. Research to improve the seed supply has already resulted in improved strains of rice, maize, wheat, kidney beans, manioc, sweet potatoes, cotton, tea and coffee. Regional seed production centers are planned to facilitate distribution and adaptation of seeds to each ecological zone. Research is underway to identify appropriate new crops and to extend the ranges of existing crops. To encourage participation of the rural population in agricultural improvement efforts, the government is financing schools and institutions which will train local level agricultural promoters and extension agents. Local governments at all levels, regional development societies, cooperatives and other structures are also being organized to assist farmers. In order to restructure and modernize the rural environment, the government has invested heavily in agricultural development and the prices of agricultural products have been raised repeatedly since 1976. Improved road networks and other infrastructure, provision of credit for agricultural improvements, and provision of affordable building materials and housing credits are among related efforts. Health interventions such as an immunization program which has achieved 50% coverage through 17 medical centers have caused some decline in the infant mortality rate. By the year 2000 according to current plans there will be 300 health centers or 1/10,000 population, and 35 hospitals compared to the 29 currently operating. The number of physicians has increased from 111 in 1980 to 216 in 1984 following addition of a medical school to the University of Burundi. The number of medical technicians has increased from 450 to 555, of auxiliary nurses from 453 to 575, of sanitary technicians from 11 to 28. In pursuit of the government objective of basic education for all children by 1987, the number of students increased from 159,729 in 1979-80 to 296,672 in 1983-84. Practical work in agriculture, artisanry, and other areas is to be introduced, and classes will be conducted in local language rather than French. Centers for nonformal education are also being introduced. Attempts are being made to assure that rural development efforts are in harmony with the culture and social aspects of life in the countryside.