CiteULike: jcherfas's library [50 articles]

Indicators for biodiversity in agricultural landscapes: a pan-European study

R Billeter — 2008-02-26T10:49:39-00:00

Journal of Applied Ecology, Vol. 45, No. 1. (2008), pp. 141-150.

Summary 1. In many European agricultural landscapes, species richness is declining considerably. Studies performed at a very large spatial scale are helpful in understanding the reasons for this decline and as a basis for guiding policy. In a unique, large-scale study of 25 agricultural landscapes in seven European countries, we investigated relationships between species richness in several taxa, and the links between biodiversity and landscape structure and management. 2. We estimated the total species richness of vascular plants, birds and five arthropod groups in each 16-km2 landscape, and recorded various measures of both landscape structure and intensity of agricultural land use. We studied correlations between taxonomic groups and the effects of landscape and land-use parameters on the number of species in different taxonomic groups. Our statistical approach also accounted for regional variation in species richness unrelated to landscape or land-use factors. 3. The results reveal strong geographical trends in species richness in all taxonomic groups. No single species group emerged as a good predictor of all other species groups. Species richness of all groups increased with the area of semi-natural habitats in the landscape. Species richness of birds and vascular plants was negatively associated with fertilizer use. 4. Synthesis and applications. We conclude that indicator taxa are unlikely to provide an effective means of predicting biodiversity at a large spatial scale, especially where there is large biogeographical variation in species richness. However, a small list of landscape and land-use parameters can be used in agricultural landscapes to infer large-scale patterns of species richness. Our results suggest that to halt the loss of biodiversity in these landscapes, it is important to preserve and, if possible, increase the area of semi-natural habitat.

Animal genetic resource trade flows: Economic assessment

Douglas Gollin — 2008-08-19T13:52:36-00:00

Livestock Science, Vol. In Press, Corrected Proof

Throughout human history, livestock producers have relied on a vibrant international exchange of genetic resources to achieve improvements in the quality and productivity of their animals. In recent years, however, some observers have argued that changes in the legal, technological, and economic environment now imply that international exchanges of animal genetic resources (AnGR) systematically benefit rich countries at the expense of poor countries. It is argued that international flows of AnGR are displacing the indigenous animal genetic resources of developing countries, and also that the genetic wealth of the developing world is being expropriated by rich countries. In reaction, there have been growing calls for limitations and/or barriers to the exchange of animal genetic resources. These discussions, however, seem to be based on limited information about the magnitude and direction of current trade flows in AnGR. This paper offers an analysis of AnGR trade flows from 1990 to 2005. The paper draws on national-level data from 150 countries that reported information to the United Nations Statistics Division. Three major trade categories were evaluated: live cattle and pigs for breeding, and cattle semen. Over the period studied, Europe and North America were the primary exporters of genetic resources for the species evaluated. OECD countries accounted for 98.7, 92.5, and 95% of cattle semen, live cattle, and swine exports in 2005, respectively. In evaluating the direction of trade between developed (North) and developing (South) countries, North-North trade had the largest magnitude, followed by North-South, South-South, and South-North. The data do not support the notion that Southern genetic resources are being used on a large scale in the North. We believe that importation from South to North is limited by the vast discrepancies in production efficiency and production systems between countries in the North and South. Given the low volume of South-North exchange, it seems doubtful that sufficient revenues could be acquired through a "benefit-sharing mechanism" to have any substantial impact on in situ or ex situ conservation efforts, or to generate benefits for poor livestock keepers in developing countries. We question whether global agreements or restrictions on trade will achieve the desired goal of conserving rare breeds and threatened genetic resources. We also doubt whether these agreements will succeed in improving the well-being of the poor. We suggest that resources instead be urgently employed for conservation and that more direct measures should be taken to aid poor farmers, ranchers, and herders in their efforts to conserve genetic resources.

Citation Advantage of Open Access Articles

Gunther Eysenbach — 2006-06-27T15:15:18-00:00

PLoS Biology, Vol. 4, No. 5. (1 May 2006)

Open access (OA) to the research literature has the potential to accelerate recognition and dissemination of research findings, but its actual effects are controversial. This was a longitudinal bibliometric analysis of a cohort of OA and non-OA articles published between June 8, 2004, and December 20, 2004, in the same journal (PNAS: Proceedings of the National Academy of Sciences). Article characteristics were extracted, and citation data were compared between the two groups at three different points in time: at “quasi-baseline” (December 2004, 0–6 mo after publication), in April 2005 (4–10 mo after publication), and in October 2005 (10–16 mo after publication). Potentially confounding variables, including number of authors, authors' lifetime publication count and impact, submission track, country of corresponding author, funding organization, and discipline, were adjusted for in logistic and linear multiple regression models. A total of 1,492 original research articles were analyzed: 212 (14.2% of all articles) were OA articles paid by the author, and 1,280 (85.8%) were non-OA articles. In April 2005 (mean 206 d after publication), 627 (49.0%) of the non-OA articles versus 78 (36.8%) of the OA articles were not cited (relative risk = 1.3 [95% Confidence Interval: 1.1–1.6]; p = 0.001). 6 mo later (mean 288 d after publication), non-OA articles were still more likely to be uncited (non-OA: 172 [13.6%], OA: 11 [5.2%]; relative risk = 2.6 [1.4–4.7]; p < 0.001). The average number of citations of OA articles was higher compared to non-OA articles (April 2005: 1.5 [SD = 2.5] versus 1.2 [SD = 2.0]; Z = 3.123; p = 0.002; October 2005: 6.4 [SD = 10.4] versus 4.5 [SD = 4.9]; Z = 4.058; p < 0.001). In a logistic regression model, controlling for potential confounders, OA articles compared to non-OA articles remained twice as likely to be cited (odds ratio = 2.1 [1.5–2.9]) in the first 4–10 mo after publication (April 2005), with the odds ratio increasing to 2.9 (1.5–5.5) 10–16 mo after publication (October 2005). Articles published as an immediate OA article on the journal site have higher impact than self-archived or otherwise openly accessible OA articles. We found strong evidence that, even in a journal that is widely available in research libraries, OA articles are more immediately recognized and cited by peers than non-OA articles published in the same journal. OA is likely to benefit science by accelerating dissemination and uptake of research findings.

Conservation of protists: is it needed at all?

F Cotterill — 2008-03-13T00:05:48-00:00

Biodiversity and Conservation, Vol. 17, No. 2. (26 February 2008), pp. 427-443.

Abstract Protists have scarcely been considered in traditional perspectives and strategies in environmental management and biodiversity conservation. This is a remarkable omission given that these tiny organisms are highly diverse, and have performed as key ecological players in evolutionary theatres for over a billion years of Earth history. Protists hold key roles in nearly all ecosystems, notably as participants in fluxes of energy and matter through foodwebs that centre on their predation on microbes. In spite of this, they have been largely ignored in conservation issues due to a widespread, naive belief that protists are ubiquitous and cosmopolitanously distributed. Nevertheless, recent research shows that many protists have markedly restricted distributions. These range from palaeoendemics (Gondwanan-Laurasian distribution) to local endemics. Our ignorance about the ultimate and proximate causes of such acute disparities in scale-dependent distributions of protists can be flagged as a singular reason to preserve these more cryptic participants in ecological and evolutionary dynamics. This argument is disturbing when one considers anthropogenic modifications of landscapes and the very poorly understood roles of protists in ecological processes in soils, not least in agroecolandscapes and hydrological systems. Major concerns include host specific symbiotic, symphoric and parasitic species which become extinct, unseen and largely unknown, alongside their metazoan hosts; change or loss of habitats; massive change or loss of type localities; and losses of unique genetic resources and evolutionary potential. These concerns are illustrated by examples to argue that conservation of protists should be integral to any strategy that traditionally targets vascular plants and animals. The ongoing decline in research capacity to inventory and classify protist diversity exemplifies a most acute symptom of the failures, at local, national and international levels, to support scientific responses to the biodiversity crisis. Responsible responses to these severe problems need to centre on the revival of natural history as the core discipline in biology.

CLIMATE: Food Security Under Climate Change

Molly Brown — 2008-02-01T14:21:02-00:00

Science, Vol. 319, No. 5863. (1 February 2008), pp. 580-581.

10.1126/science.1154102

Glycemic index, glycemic load, and chronic disease risk--a meta-analysis of observational studies.

AW Barclay — 2008-03-12T08:23:34-00:00

Am J Clin Nutr, Vol. 87, No. 3. (March 2008), pp. 627-637.

BACKGROUND: Inconsistent findings from observational studies have prolonged the controversy over the effects of dietary glycemic index (GI) and glycemic load (GL) on the risk of certain chronic diseases. OBJECTIVE: The objective was to evaluate the association between GI, GL, and chronic disease risk with the use of meta-analysis techniques. DESIGN: A systematic review of published reports identified a total of 37 prospective cohort studies of GI and GL and chronic disease risk. Studies were stratified further according to the validity of the tools used to assess dietary intake. Rate ratios (RRs) were estimated in a Cox proportional hazards model and combined by using a random-effects model. RESULTS: From 4 to 20 y of follow-up across studies, a total of 40 129 incident cases were identified. For the comparison between the highest and lowest quantiles of GI and GL, significant positive associations were found in fully adjusted models of validated studies for type 2 diabetes (GI RR = 1.40, 95% CI: 1.23, 1.59; GL RR = 1.27, 95% CI: 1.12, 1.45), coronary heart disease (GI RR = 1.25, 95% CI: 1.00, 1.56), gallbladder disease (GI RR = 1.26, 95% CI: 1.13, 1.40; GL RR = 1.41, 95% CI: 1.25, 1.60), breast cancer (GI RR = 1.08, 95% CI: 1.02, 1.16), and all diseases combined (GI RR = 1.14, 95% CI: 1.09, 1.19; GL RR = 1.09, 95% CI: 1.04, 1.15). CONCLUSIONS: Low-GI and/or low-GL diets are independently associated with a reduced risk of certain chronic diseases. In diabetes and heart disease, the protection is comparable with that seen for whole grain and high fiber intakes. The findings support the hypothesis that higher postprandial glycemia is a universal mechanism for disease progression.

Questioning the ecosystem services argument for biodiversity conservation

Ben Ridder — 2008-03-04T10:29:00-00:00

Biodiversity and Conservation

Abstract One of the central justifications for the conservation of biodiversity is the notion that species diversity is essential for the maintenance of ecosystem services. However, an important observation overlooked by proponents of this argument is that most ecosystem services are provided not by whole ecosystems, but by any group of species that fulfils certain basic functional criteria. Distinguishing between services that are resilient in response to species decline, and those that are not, is a far less challenging task than identifying the precise influence on ecosystem functioning of rare species. Conservationists have been almost unanimous in their failure to acknowledge this distinction between resilient and sensitive ecosystem services. Not only does this threaten the credibility of conservation science, but also increases the likelihood that natural area management becomes hijacked by the demand that ecosystem service provision be made the dominant management criteria.

Maternal and child undernutrition: global and regional exposures and health consequences

Robert Black — 2008-02-15T14:58:58-00:00

The Lancet, Vol. 371, No. 9608., pp. 243-260.

Summary Maternal and child undernutrition is highly prevalent in low-income and middle-income countries, resulting in substantial increases in mortality and overall disease burden. In this paper, we present new analyses to estimate the effects of the risks related to measures of undernutrition, as well as to suboptimum breastfeeding practices on mortality and disease. We estimated that stunting, severe wasting, and intrauterine growth restriction together were responsible for 2[middle dot]2 million deaths and 21% of disability-adjusted life-years (DALYs) for children younger than 5 years. Deficiencies of vitamin A and zinc were estimated to be responsible for 0[middle dot]6 million and 0[middle dot]4 million deaths, respectively, and a combined 9% of global childhood DALYs. Iron and iodine deficiencies resulted in few child deaths, and combined were responsible for about 0[middle dot]2% of global childhood DALYs. Iron deficiency as a risk factor for maternal mortality added 115[punctuation space]000 deaths and 0[middle dot]4% of global total DALYs. Suboptimum breastfeeding was estimated to be responsible for 1[middle dot]4 million child deaths and 44 million DALYs (10% of DALYs in children younger than 5 years). In an analysis that accounted for co-exposure of these nutrition-related factors, they were together responsible for about 35% of child deaths and 11% of the total global disease burden. The high mortality and disease burden resulting from these nutrition-related factors make a compelling case for the urgent implementation of interventions to reduce their occurrence or ameliorate their consequences.

A Global Assessment of Salmon Aquaculture Impacts on Wild Salmonids

Jennifer Ford — 2008-02-13T09:56:31-00:00

PLoS Biology, Vol. 6, No. 2. (1 February 2008), e33.

Since the late 1980s, wild salmon catch and abundance have declined dramatically in the North Atlantic and in much of the northeastern Pacific south of Alaska. In these areas, there has been a concomitant increase in the production of farmed salmon. Previous studies have shown negative impacts on wild salmonids, but these results have been difficult to translate into predictions of change in wild population survival and abundance. We compared marine survival of salmonids in areas with salmon farming to adjacent areas without farms in Scotland, Ireland, Atlantic Canada, and Pacific Canada to estimate changes in marine survival concurrent with the growth of salmon aquaculture. Through a meta-analysis of existing data, we show a reduction in survival or abundance of Atlantic salmon; sea trout; and pink, chum, and coho salmon in association with increased production of farmed salmon. In many cases, these reductions in survival or abundance are greater than 50%. Meta-analytic estimates of the mean effect are significant and negative, suggesting that salmon farming has reduced survival of wild salmon and trout in many populations and countries.

Nonhematological Benefits of Iron

R Agarwal — 2008-01-11T13:53:01-00:00

American Journal of Nephrology, Vol. 27 (2007), pp. 565-571.

Iron deficiency anemia is common in people with chronic kidney disease (CKD) and its importance in supporting erythropoiesis is unquestioned especially in those patients treated with erythropoietin. Clinical symptomatology such as fatigability, cold intolerance, failure to concentrate and poor effort intolerance is often attributed to anemia or uremia. That iron deficiency, per se, can cause these symptoms is poorly recognized. Clinical and animal studies that support the benefits of iron supplementation, independent of increasing hemoglobin, such as those on immune function, physical performance, thermoregulation, cognition, and restless leg syndrome and aluminum absorption is the subject of this narrative review.

The importance of β-carotene as a source of vitamin A with special regard to pregnant and breastfeeding women

Manuela Strobel — 2008-01-11T13:50:15-00:00

European Journal of Nutrition, Vol. 46, No. 0. (2007), pp. 1-20.

Summary Vitamin A is essential for growth and differentiation of a number of cells and tissues. Notably during pregnancy and throughout the breastfeeding period, vitamin A has an important role in the healthy development of the fetus and the newborn, with lung development and maturation being particularly important. The German Nutrition Society (DGE) recommends a 40% increase in vitamin A intake for pregnant women and a 90% increase for breastfeeding women. However, pregnant women or those considering becoming pregnant are generally advised to avoid the intake of vitamin A rich liver and liver foods, based upon unsupported scientific findings. As a result, the provitamin A carotenoid β-carotene remains their essential source of vitamin A. Basic sources of provitamin A are orange and dark green vegetables, followed by fortified beverages which represent between 20% and 40% of the daily supply. The average intake of β-carotene in Germany is about 1.5–2 mg a day. Assuming a vitamin A conversion rate for β-carotene for juices of 4:1, and fruit and vegetables between 12:1 and 26:1; the total vitamin A contribution from β-carotene intake represents 10–15% of the RDA. The American Pediatrics Association cites vitamin A as one of the most critical vitamins during pregnancy and the breastfeeding period, especially in terms of lung function and maturation. If the vitamin A supply of the mother is inadequate, her supply to the fetus will also be inadequate, as will later be her milk. These inadequacies cannot be compensated by postnatal supplementation. A clinical study in pregnant women with short birth intervals or multiple births showed that almost 1/3 of the women had plasma retinol levels below 1.4 �mol/l corresponding to a borderline deficiency. Despite the fact that vitamin A and beta-carotene rich food is generally available, risk groups for low vitamin A supply exist in the western world. It is therefore highly critical to restrict the β-carotene supply from diet, particularly from sources of β-carotene with high consumer acceptance such as fortified juices (e.g. “ACE juices”) or dietary supplements (e.g. multivitamins for pregnant women). For the part of the population unable to meet vitamin A requirements according to the DACH recommendations, sufficient intake of β-carotene may be crucial to help improve and maintain adequate vitamin A status and prevention of developmental disorders. At this time it has to be urgently advised against restricting the β-carotene supply or putting warning labels on β-carotene fortified products. It is, however, highly recommended to improve the available data on nutrient intakes in Germany, especially for pregnant and breastfeeding women. For them, recommendations to be aware of potential nutrient intake inadequacies might prove useful.

Global-scale mapping of economic benefits from agricultural lands: Implications for conservation priorities

Robin Naidoo — 2007-11-06T09:18:35-00:00

Biological Conservation, Vol. 140, No. 1-2. (November 2007), pp. 40-49.

Research in systematic conservation planning has focused heavily on biological considerations, even though a growing number of studies demonstrate that integrating economic costs into the planning process markedly increases the efficiency of resulting plans. At the global scale, the availability of biodiversity maps is increasing, but analogous maps for economic factors that affect biodiversity conservation are rare, and no study has examined global conservation planning at high resolution using both biodiversity and cost information. Here, we integrate spatial information on crop productivity, livestock density, and prices to produce a global map of the gross economic rents from agricultural lands. We then illustrate the importance of including such opportunity costs in global planning for the conservation of endemic vertebrate species. Plans that consider costs represent endemic species at 10-33% of the opportunity cost of plans that do not, and produce priority sets that diverge from existing schemes. Given scarce resources and the great cost-effectiveness of plans that consider both biodiversity and costs, mapping of the economic costs of conservation should receive similar levels of research attention as mapping of biodiversity.

The coincidence of people and biodiversity in Europe

Miguel Araujo — 2007-08-06T11:59:58-00:00

Global Ecology and Biogeography, Vol. 12, No. 1. (2003), pp. 5-12.

ABSTRACT A positive correlation between human population density and species richness has been recorded across the tropics. Here I investigate whether this correlation holds true for Europe. Analyses reveal a positive correlation between human population density and plant (rho = 0.505), mammal (rho = 0.471) and reptile and amphibian (rho = 0.556) species richness. The results are largely concordant with those obtained in similar studies for Africa. However, contrary to previous analyses, the correlation found between people and breeding bird species richness (rho = 0.186) was weak. Of three measures of endemism used, only combined European endemic species richness correlated with human density (rho = 0.437). Richness among combined restricted-range European endemics was not correlated (rho = 0.095) with human density, while richness among all combined restricted-range species was only weakly correlated with human density (rho = 0.167). The results partially support the idea of a correlation between people and biodiversity, although there are some important exceptions. Discussion of possible mechanisms underling the observed patterns is undertaken.

ECOLOGY: How Does Climate Change Affect Biodiversity?

Miguel Araujo — 2006-09-12T00:00:39-00:00

Science, Vol. 313, No. 5792. (8 September 2006), pp. 1396-1397.

10.1126/science.1131758

Dietary glycemic index, glycemic load, and the risk of breast cancer in an Italian prospective cohort study.

S Sieri — 2007-10-10T14:50:24-00:00

Am J Clin Nutr, Vol. 86, No. 4. (October 2007), pp. 1160-1166.

BACKGROUND: Interest in the roles of glycemic index (GI) and glycemic load (GL) in breast cancer etiology has been stimulated by indications that disease risk is linked to insulinemia, sex hormone bioavailability, and insulin-like growth factor 1. OBJECTIVE: We aimed to determine whether GI and GL were associated with the risk of breast cancer in a cohort of Italian women volunteers from Northern Italy, who enrolled between 1987-1992 in the Hormones and Diet in the Etiology of Breast Tumors Study (ORDET Study). DESIGN: Volunteers completed a semiquantitative food-frequency questionnaire, and anthropometric and lifestyle data were collected. Dietary GI and GL in relation to breast cancer risk were examined in 8926 cohort women, including 289 with breast cancer identified after a mean follow-up of 11.5 y. RESULTS: The relative risk (RR) of breast cancer in the highest (versus lowest) quintiles of GI and GL was 1.57 (95% CI: 1.04, 2.36; P for trend = 0.040) and 2.53 (95% CI: 1.54, 4.16; P for trend = 0.001), respectively. Total carbohydrate intake was not associated with greater breast cancer risk, but high carbohydrate from high-GI foods was. When women were categorized by baseline menopausal status and body mass index (BMI; in kg/m(2)), the increased risk of dietary GL was confined to those who were premenopausal (RR = 3.89; 95% CI: 1.81, 8.34) and who had normal BMI (ie, <25) (RR = 5.79; 95% CI: 2.60, 12.90) (P for trend = 0.001 for both). CONCLUSIONS: A high-GL diet may increase the risk of breast cancer in Italian women. The effect is particularly evident in premenopausal women and those with BMI < 25.

The effects of maternal and infant vitamin A supplementation on vitamin A status: a randomised trial in Kenya.

RA Ayah — 2007-10-03T09:12:44-00:00

Br J Nutr, Vol. 98, No. 2. (August 2007), pp. 422-430.

Postpartum vitamin A supplementation of mothers and infants is recommended, but the efficacy has been questioned. In this double-blind, placebo-controlled trial, Kenyan mother-infant pairs were randomised to maternal vitamin A (400,000 IU) or placebo <24 h postpartum, and infant vitamin A (100,000 IU) or placebo at 14 weeks. Milk retinol was determined at weeks 4, 14 and 26, and maternal and infant serum retinol at weeks 14 and 26. Infant retinol stores were assessed at week 26, using a modified relative dose response (MRDR) test. Among 564 women, serum retinol at 36 weeks gestation was 0.81 (SD 0.21) micromol/l, and 33.3% were<0.7 micromol/l. Maternal serum retinol was not different between groups, but milk retinol was higher in the vitamin A group: (0.67 v. 0.60 micromol/l; 0.52 v. 0.44 micromol/l; 0.50 v. 0.44 micromol/l at 4, 14 and 26 weeks, respectively). When expressed per gram fat, milk retinol was higher in the vitamin A group only at 4 weeks. Infant serum retinol was not different between groups. However, although most infants had deficient vitamin A stores (MRDR>0.06%) at 26 weeks, vitamin A to infants, but not mothers, resulted in a lower proportion of infants with deficient vitamin A stores (69 v. 78 %). High-dose postpartum vitamin A supplementation failed to increase serum retinol and infant stores, despite modest effects on milk retinol. Infant supplementation, however, increased stores. There is a need for a better understanding of factors affecting absorption and metabolism of vitamin A.

Trypanosoma cruzi: treatment with the iron chelator desferrioxamine reduces parasitemia and mortality in experimentally infected mice.

JM Arantes — 2007-10-03T09:11:44-00:00

Exp Parasitol, Vol. 117, No. 1. (September 2007), pp. 43-50.

The effects of prolonged treatment with iron chelator (desferrioxamine) on the development of infection in mice inoculated with Y Trypanosoma cruzi were determined. Infected/treated mice presented lower levels of parasitemia and reduced mortality rate compared with infected/non-treated animals. The five out of twenty infected/treated mice that survived the acute phase of infection showed negative hemoculture and positive ELISA in the acute and chronic phases and positive PCR in the acute phase: in the chronic phase, three of the animals presented negative PCR. The single surviving infected/non-treated animal exhibited positive hemoculture, PCR and ELISA in both phases of infection. Infected groups presented lower levels of iron in the liver compared with treated/non-infected or non-treated/non-infected animals. The serum iron levels of the infected/non-treated group were higher on the 21st day post-infection in comparison with control and infected/treated groups. These results suggest that decrease of iron in the host leads to T. cruzi infection attenuation.

Iron deficiency anaemia and evaluation of the utility of iron deficiency indicators among healthy Nigerian children.

ZA Jeremiah — 2007-10-03T09:11:07-00:00

Hematology, Vol. 12, No. 3. (June 2007), pp. 249-253.

The hemoglobin (Hb), serum iron (SI), total iron binding capacity (TIBC), transferrin saturation (TS) and serum ferritin (SF) values of 240 apparently healthy children were determined in a prospective cross-sectional study conducted in Port Harcourt, Nigeria. Standard colorimetric and enzyme immunoassay procedures were used for the estimation all variables. The mean values of all parameters in this study population were; Hb (11.2 +/- 1.83 gldl), TIBC (361.4 +/- 245.7 ugldl, log(c) SI (1.807 +/- 0.45), log(c) SF (1.51 +/- 0.47) and TS (29.3 +/- 18.5%). There was an age-dependent statistical significant difference in the Hb, TIBC and TS values (P < 0.01). Sex was not found to exert any significant influence on the parameters except TIBC. TS had the highest sensitivity and efficiency values of 48 and 95%, respectively. Positive predictive value (PPV), likelihood ratio (LR(+)) and post-test probability values were highest with SF (58%, 3.3 and 62.2%, respectively) as a diagnostic indicator. Hb values correlated positively and significantly with TS (P < 0.01), log(c) SI and log(c) SF concentrations (P < 0.05). Log(c) SF also correlated positively and significantly with Hb and TIBC (P < 0.05). The overall prevalence of iron deficiency anaemia among these children was 33.75%. We conclude that there is a high prevalence of iron deficiency anaemia among apparently healthy children under the age of five years in this part of the world and these results may justify the need for the introduction of a broad intervention programme for this highly vulnerable group. This study is also in support of the hypothesis that SF is the best test for diagnosing or excluding iron deficiency anaemia. The combination of SF, Hb and TS determinations may prove more useful in a resource-limited moderate setting.

Glycaemic index of common foods tested in the UK and India.

C J K Henry — 2007-10-03T08:25:06-00:00

Br J Nutr (1 October 2007), pp. 1-6.

The aim of this study was to ascertain whether international glycaemic index (GI) values, predominantly developed using peoples living in Europe, North America or Australia, are applicable to Asian Indians resident in their own country. Thirty-four Caucasian subjects were recruited in Oxford, UK and thirteen Asian Indian subjects in Chennai, India. Two types of sweet biscuits and three breakfast cereals were tested for glycaemic response in each group. Subjects were served equivalent available carbohydrate amounts (50 g) of test foods and a reference food (glucose), on separate occasions. Capillary blood glucose was measured from finger-prick samples in fasted subjects ( - 5 and 0 min) and at 15, 30, 45, 60, 90 and 120 min after starting to eat. For each test food, the incremental area under the curve (IAUC) and GI values were determined. Although the glycaemic response to the reference food was higher in Asian Indian subjects compared with UK Caucasian subjects (IAUC 219 mmol/min per litre v. 157 mmol/min per litre, respectively; P < 0.01), there was no significant difference in GI values of the five test foods between the two groups. This is the first study known to the authors to examine the role of ethnicity on GI when the subjects are resident in their own countries. The findings from this study have important implications for the use of the GI concept worldwide and support the application of international values to different ethnic groups. The higher glycaemic response to all foods in Asian Indians may represent another mechanism for increased diabetes susceptibility among Asian Indians.

Iron bioavailability as a protective factor against anemia among children aged 12 to 16 months.

MR Vitolo — 2007-09-12T09:54:51-00:00

J Pediatr (Rio J), Vol. 83, No. 1. (b 2007), pp. 33-38.

OBJECTIVE: This study investigates the nutritional factors that determine the absence of anemia in infants from families with a low socioeconomic background submitted to a nutrition intervention program, as well as iron intake according to recommendations. METHODS: The study included 369 children from a cohort of inhabitants of São Leopoldo, state of Rio Grande do Sul, Brazil, who were randomized at birth into an intervention group and into a control group. The intervention group had nutritional guidance in the first year of life, with monthly follow-up home visits, whereas the control group was visited at 6 and 12 months, without nutritional intervention. At the end of the first year of life, a 24-hour recall was used. Anemia was diagnosed based on a hemoglobin level less than 11 g/dL. The children's diets were classified according to iron bioavailability. RESULTS: The prevalence of anemia amounted to 63.7% in this study. The proportion of children with adequate iron intake relative to the recommendations was statistically higher in the nonanemic group (26.8%) than in the anemic one (17.7%). Nonanemic children had a greater intake of iron (p = 0.019), vitamin C (p = 0.001), energy density at dinner (p = 0.006), iron density per 1,000 calories (p = 0.045); and 16.3% of them had a diet with high iron bioavailability (p = 0.002). CONCLUSIONS: A diet with high iron bioavailability protects children from anemia and can be used as an intervention measure by basic health services and by the municipal departments of children's education.

A prospective study of plasma vitamin D metabolites, vitamin D receptor polymorphisms, and prostate cancer.

H Li — 2007-09-12T09:53:16-00:00

PLoS Med, Vol. 4, No. 3. (March 2007)

BACKGROUND: Vitamin D insufficiency is a common public health problem nationwide. Circulating 25-hydroxyvitamin D3 (25[OH]D), the most commonly used index of vitamin D status, is converted to the active hormone 1,25 dihydroxyvitamin D3 (1,25[OH]2D), which, operating through the vitamin D receptor (VDR), inhibits in vitro cell proliferation, induces differentiation and apoptosis, and may protect against prostate cancer. Despite intriguing results from laboratory studies, previous epidemiological studies showed inconsistent associations of circulating levels of 25(OH)D, 1,25(OH)2D, and several VDR polymorphisms with prostate cancer risk. Few studies have explored the joint association of circulating vitamin D levels with VDR polymorphisms. METHODS AND FINDINGS: During 18 y of follow-up of 14,916 men initially free of diagnosed cancer, we identified 1,066 men with incident prostate cancer (including 496 with aggressive disease, defined as stage C or D, Gleason 7-10, metastatic, and fatal prostate cancer) and 1,618 cancer-free, age- and smoking-matched control participants in the Physicians' Health Study. We examined the associations of prediagnostic plasma levels of 25(OH)D and 1,25(OH)2D, individually and jointly, with total and aggressive disease, and explored whether relations between vitamin D metabolites and prostate cancer were modified by the functional VDR FokI polymorphism, using conditional logistic regression. Among these US physicians, the median plasma 25(OH)D levels were 25 ng/ml in the blood samples collected during the winter or spring and 32 ng/ml in samples collected during the summer or fall. Nearly 13% (summer/fall) to 36% (winter/spring) of the control participants were deficient in 25(OH)D (<20 ng/ml) and 51% (summer/fall) and 77% (winter/spring) had insufficient plasma 25(OH)D levels (<32 ng/ml). Plasma levels of 1,25(OH)2D did not vary by season. Men whose levels for both 25(OH)D and 1,25(OH)2D were below (versus above) the median had a significantly increased risk of aggressive prostate cancer (odds ratio [OR] = 2.1, 95% confidence interval [CI] 1.2-3.4), although the interaction between the two vitamin D metabolites was not statistically significant (pinteraction = 0.23). We observed a significant interaction between circulating 25(OH)D levels and the VDR FokI genotype (pinteraction < 0.05). Compared with those with plasma 25(OH)D levels above the median and with the FokI FF or Ff genotype, men who had low 25(OH)D levels and the less functional FokI ff genotype had increased risks of total (OR = 1.9, 95% CI 1.1-3.3) and aggressive prostate cancer (OR = 2.5, 95% CI 1.1-5.8). Among men with plasma 25(OH)D levels above the median, the ff genotype was no longer associated with risk. Conversely, among men with the ff genotype, high plasma 25(OH)D level (above versus below the median) was related to significant 60% approximately 70% lower risks of total and aggressive prostate cancer. CONCLUSIONS: Our data suggest that a large proportion of the US men had suboptimal vitamin D status (especially during the winter/spring season), and both 25(OH)D and 1,25(OH)2D may play an important role in preventing prostate cancer progression. Moreover, vitamin D status, measured by 25(OH)D in plasma, interacts with the VDR FokI polymorphism and modifies prostate cancer risk. Men with the less functional FokI ff genotype (14% in the European-descent population of this cohort) are more susceptible to this cancer in the presence of low 25(OH)D status.

Domestication of Plants in the Americas: Insights from Mendelian and Molecular Genetics

Barbara Pickersgill — 2007-09-06T06:28:57-00:00

Ann Bot (31 August 2007), mcm193.

BackgroundPlant domestication occurred independently in four different regions of the Americas. In general, different species were domesticated in each area, though a few species were domesticated independently in more than one area. The changes resulting from human selection conform to the familiar domestication syndrome, though different traits making up this syndrome, for example loss of dispersal, are achieved by different routes in crops belonging to different families. Genetic and Molecular Analyses of DomesticationUnderstanding of the genetic control of elements of the domestication syndrome is improving as a result of the development of saturated linkage maps for major crops, identification and mapping of quantitative trait loci, cloning and sequencing of genes or parts of genes, and discoveries of widespread orthologies in genes and linkage groups within and between families. As the modes of action of the genes involved in domestication and the metabolic pathways leading to particular phenotypes become better understood, it should be possible to determine whether similar phenotypes have similar underlying genetic controls, or whether human selection in genetically related but independently domesticated taxa has fixed different mutants with similar phenotypic effects. ConclusionsSuch studies will permit more critical analysis of possible examples of multiple domestications and of the origin(s) and spread of distinctive variants within crops. They also offer the possibility of improving existing crops, not only major food staples but also minor crops that are potential export crops for developing countries or alternative crops for marginal areas. 10.1093/aob/mcm193

Vitamin D deficiency: A global perspective.

F Bandeira — 2007-09-04T08:37:12-00:00

Arq Bras Endocrinol Metabol, Vol. 50, No. 4. (August 2006), pp. 640-646.

Vitamin D is essential for the maintenance of good health. Its sources can be skin production and diet intake. Most humans depend on sunlight exposure (UVB 290-315 nm) to satisfy their requirements for vitamin D. Solar ultraviolet B photons are absorbed by the skin, leading to transformation of 7-dehydrocholesterol into vitamin D3 (cholecalciferol). Season, latitude, time of day, skin pigmentation, aging, sunscreen use, all influence the cutaneous production of vitamin D3. Vitamin D deficiency not only causes rickets among children but also precipitates and exacerbates osteoporosis among adults and causes the painful bone disease osteomalacia. Vitamin D deficiency has been associated with increased risk for other morbidities such as cardiovascular disease, type 1 and type 2 diabetes mellitus and cancer, especially of the colon and prostate. The prevalence of hypovitaminosis D is considerable even in low latitudes and should be taken into account in the evaluation of postmenopausal and male osteoporosis. Although severe vitamin D deficiency leading to rickets or osteomalacia is rare in Brazil, there is accumulating evidence of the frequent occurrence of subclinical vitamin D deficiency, especially in elderly people.

A low glycaemic index breakfast cereal preferentially prevents children's cognitive performance from declining throughout the morning.

J Ingwersen — 2007-09-04T06:54:09-00:00

Appetite, Vol. 49, No. 1. (July 2007), pp. 240-244.

This study investigated whether the glycaemic index (GI) of breakfast cereal differentially affects children's attention and memory. Using a balanced cross-over design, on two consecutive mornings 64 children aged 6-11 years were given a high GI cereal and a low GI cereal in a counterbalanced order. They performed a series of computerised tests of attention and memory, once prior to breakfast and three times following breakfast at hourly intervals. The results indicate that children's performance declines throughout the morning and that this decline can be significantly reduced following the intake of a low GI cereal as compared with a high GI cereal on measures of accuracy of attention (M=-6.742 and -13.510, respectively, p<0.05) and secondary memory (M=-30.675 and -47.183, respectively, p<0.05).

High dietary glycemic load and glycemic index increase risk of cardiovascular disease among middle-aged women: a population-based follow-up study.

JW Beulens — 2007-09-04T06:30:50-00:00

J Am Coll Cardiol, Vol. 50, No. 1. (3 July 2007), pp. 14-21.

OBJECTIVES: The goal of this work was to assess whether high dietary glycemic load and glycemic index are associated with an increased risk of cardiovascular disease (CVD). BACKGROUND: The associations of dietary glycemic index and glycemic load with risk of CVD are not well established, particularly in populations consuming modest glycemic load diets. Moreover, risk may differ between lean and overweight subjects. METHODS: Associations of glycemic index and glycemic load with incident CVD were examined in a prospective cohort of 15,714 Dutch women age 49 to 70 years without diabetes or CVD. Dietary glycemic index and glycemic load were calculated using the glycemic index, carbohydrate content, and frequency of intake of individual foods. RESULTS: During 9 +/- 2 years of follow-up, 556 cases of coronary heart disease (CHD) and 243 cases of cerebrovascular accident (CVA) occurred. Dietary glycemic load (mean = 100; SD = 17) was associated with increased risk of CVD, adjusted for CVD risk factors and dietary variables, with a hazard ratio (HR) for the highest against lowest quartile of 1.47 (95% confidence interval [CI] 1.04 to 2.09; p(trend) = 0.03). Similar results were observed for dietary glycemic index with a corresponding HR of 1.33 (95% CI 1.07 to 1.67; p(trend) = 0.02). Glycemic load tended to be associated with both CHD (HR 1.44; 95% CI 0.95 to 2.19; p(trend) = 0.14) and CVA (HR 1.55; 95% CI 0.81 to 2.97; p(trend) = 0.10), but glycemic index only with CHD (HR 1.44; 95% CI 1.10 to 1.89; p(trend) = 0.01). Among overweight women (body mass index >25 kg/m2), glycemic load was associated with CVD (1.78; 95% CI 1.11 to 2.85; p(trend) = 0.04), but not among normal weight women (p(interaction) = 0.19). Body mass index did not modify the association of glycemic index with CVD. CONCLUSIONS: Among women consuming modest glycemic load diets, high dietary glycemic load and glycemic index increase the risk of CVD, particularly for overweight women.

A fresh look at shifting cultivation: Fallow length an uncertain indicator of productivity

Ole Mertz — 2007-08-06T07:08:34-00:00

Agricultural Systems, Vol. In Press, Corrected Proof

Shifting cultivation is practiced by millions of farmers in the tropics and has been accused of causing deforestation and keeping farmers in poverty. The assumed positive relationship between fallow length and crop yields has long shaped such negative opinions on the sustainability and environmental impact of the system, as population growth is believed inevitably to lead to its collapse. Empirical evidence for this assumption is scarce, however, and a better understanding of system dynamics is needed before discarding shifting cultivation as unsustainable. With cases from Malaysia and Indonesia, we show that fallow length is a weak predictor of crop yields, though interactions with fertilizer inputs may increase its importance. Other factors such as drought, flooding, and pests are more important determinants of yields. The implication is that when using natural fallow as the only means of nutrient supply, there is no need to cut old fallow vegetation. Moreover, there is no evidence of system collapse, even at short fallow periods. We conclude that shifting cultivation should be accepted as a rational land use system and that earlier calls for bringing a "Green Revolution" to shifting cultivators are still relevant to achieve intensive and sustainable production.

Does Low Biodiversity Resulting from Modern Agricultural Practice Affect Crop Pollination and Yield?

AJ Richards — 2007-05-27T21:59:51-00:00

pp. 165-172.

This Botanical Briefing examines the hypothesis that modern agricultural practice affects natural biotic pollination to the extent that crop yields suffer. Few staple foods depend on animal pollination and relatively few other crops are totally dependent on animal pollination. However, there are many crops of local economic importance whose yield or quality may be enhanced by good pollinator activity: studies of these deserve more attention. Amongst those cases already documented, intensification and habitat loss are the most frequent causes of pollinator impoverishment reducing crop yield. As yet there is no clear example of low crop yield resulting from the effect of pesticides or transgenic plants on pollinators, and only one example involving herbicides, although each of these agents can affect populations of crop pollinators. Copyright 2001 Annals of Botany Company

Agricultural Biodiversity in Northwest Somalia an Assessment Among Selected Somali Sorghum(Sorghum bicolor (L.) Moench) Germplasm

Marco Manzelli — 2005-12-21T05:30:17-00:00

Biodiversity and Conservation, Vol. 14, No. 14. (December 2005), pp. 3381-3392.

Agricultural Biodiversity is Essential for Adapting to Climate Change

Kotschi — 2007-07-09T10:35:33-00:00

GAIA - Ecological Perspectives for Science and Society, Vol. 16, No. 2. (June 2007), pp. 98-101.

Long-term enhancement of agricultural production by restoration of biodiversity

James Bullock — 2007-01-06T00:40:42-00:00

Journal of Applied Ecology, Vol. 44, No. 1. (February 2007), pp. 6-12.

GM-gene-deletor: fused loxP-FRT recognition sequences dramatically improve the efficiency of FLP or CRE recombinase on transgene excision from pollen and seed of tobacco plants

Luo — 2007-02-25T17:45:27-00:00

Plant Biotechnology Journal, Vol. 5, No. 2. (March 2007), pp. 263-374.

The unappreciated ecology of landrace populations: Conservation consequences of soil seed banks in Cassava

Benoit Pujol — 2007-02-26T07:35:04-00:00

Biological Conservation, Vol. In Press, Corrected Proof

Failure to take into account the ecological complexity of landrace populations of crop plants limits our ability to conserve their genetic resources in situ. Soil seed banks are a central feature of the ecology of landrace populations of cassava; their existence has consequences for conservation. Seedlings recruited from seed banks are incorporated by farmers into their stocks of clones of this vegetatively propagated crop, transforming pure clonality into a mixed clonal/sexual reproductive system. Soil seed banks, and farmers' responses to them, play an important role in maintaining diversity in populations of cassava landraces. In a study combining genetic and ethnobiological approaches, we showed the following: (i) Recruitment from soil seed banks increased diversity of populations at the local scale. At the level of a field, the presence of plants issued from seeds resulted in significantly greater diversity of genotypes and phenotypes than if only individuals planted by farmers had been present. (ii) Farmers' use of seed banks has enabled indirect `exchange' of locally adapted cassava germplasm between cultural groups, without requiring that groups actually encountered one another and engaged in social exchange of cultivars. (iii) Farmers have responded to catastrophic crop failure by using seed banks to regenerate stocks of clones. This use of seed banks should enable cassava populations to respond to disasters by an increase of genetic diversity, rather than by a narrowing of the genetic base, often feared in such situations.

Fortified foods: friend or foe?

AP Nugent — 2004-12-28T16:17:02-00:00

Nutrition Bulletin, Vol. 29, No. 4., 295.

The role of foreign direct investment in the nutrition transition

Corinna Hawkes — 2005-06-25T21:01:51-00:00

Public Health Nutrition, Vol. 8, No. 4. (June 2005), pp. 357-365.

Uneven dietary development: linking the policies and processes of globalization with the nutrition transition, obesity and diet-related chronic diseases

Corinna Hawkes — 2006-06-06T10:32:43-00:00

Globalization and Health, Vol. 2 (28 March 2006), 4.

Iron and vitamin a deficiency in long-term african refugees.

AJ Seal — 2005-04-01T06:37:47-00:00

J Nutr, Vol. 135, No. 4. (April 2005), pp. 808-813.

Five cross-sectional surveys were conducted in African refugee camps to assess the level of iron deficiency anemia and vitamin A deficiency in populations dependent on long-term international food aid and humanitarian assistance. The prevalence of anemia in children [hemoglobin (Hb) <110 g/L] was high, with >60% affected in 3 of 5 camps. Iron deficiency [serum transferrin receptor (sTfR) >8.5 mg/L] was also high, ranging from 23 to 75%; there was also a strong ecological correlation between the prevalence of iron deficiency and anemia among different camps. Within camps, sTfR predicted the concentration of Hb with adjusted R(2) values ranging from 0.19 to 0.51. Although children were more affected, anemia was also a public health problem in adolescents and women. The effect of recent recommendations on Hb cutoff values for African populations was assessed and found to produce decreases in the prevalence of anemia of between 5 and 21%; this did not affect the public health categorization of the anemia problem within the most affected camps. Mean serum retinol in children, after adjustment for infection status, ranged from 0.72 +/- 0.2 to 0.88 +/- 0.2 mumol/L in the 4 camps assessed and vitamin A deficiency (<0.7 mumol/L) was present at levels ranging from 20.5 to 61.7%. In areas in which vitamin A capsule distribution programs were in effect, coverage ranged from 3.5 up to 66.2%. The high level of micronutrient deficiencies seen in long-term refugees argues in favor of further enhancements in food aid fortification and the strengthening of nutrition and public health programs.

Biofortification, biodiversity and diet: A search for complementary applications against poverty and malnutrition

Timothy Johns — 2007-02-21T14:04:35-00:00

Food Policy, Vol. 32, No. 1. (February 2007), pp. 1-24.

Biofortification, the focus of the HarvestPlus program of the Consultative Group on International Agriculture Research (CGIAR), represents a potentially powerful tool to increase dietary intake of essential nutrients in staple foods. This paper evaluates the compatibility of biofortification with the preferred option of dietary diversification and its potential impacts on the agricultural biodiversity essential for long term sustainability. In poor countries, biofortification requires increasing public investment in agricultural research and infrastructure for success. Rather than cereal commodities, biofortification for developing countries should focus on vegetatively propagated species or in improving quality of coarse cereals, as well as fodders. Community participatory approaches that identify local food resources with nutritional, agronomic and economic advantages to small-scale farmers could complement and set targets for biofortification as one of many approaches to alleviate nutritional deficiencies. Furthermore using agricultural biodiversity to reinforce dietary diversity can help situate biofortification within the larger context of sustainable food-based approaches. In this light, this paper evaluates specific biofortification interventions from environmental, sociocultural, political, economic, ethical, and biomedical perspectives.

Soil biodiversity for agricultural sustainability

Lijbert Brussaard — 2007-02-21T13:57:25-00:00

Agriculture, Ecosystems & Environment, Vol. In Press, Corrected Proof

We critically highlight some evidence for the importance of soil biodiversity to sustaining (agro-)ecosystem functioning and explore directions for future research. We first deal with resistance and resilience against abiotic disturbance and stress. There is evidence that soil biodiversity does confer stability to stress and disturbance, but the mechanism is not yet fully understood. It appears to depend on the kind of stress and disturbance and on the combination of stress and disturbance effects. Alternatively, community structure may play a role. Both possible explanations will guide further research. We then discuss biotic stress. There is evidence that soil microbial diversity confers protection against soil-borne disease, but crop and soil type and management also play a role. Their relative importance as well as the role of biodiversity in multitrophic interactions warrant further study. Henceforth, we focus on the effects of plant and soil biodiversity on nutrient and water use efficiencies as important ecological functions in agroecosystems. The available evidence suggests that mycorrhizal diversity positively contributes to nutrient and, possibly, water use efficiency. Soil fauna effects on nutrient and water use efficiencies are also apparent, but diversity effects may be indirect, through effects on soil structure. We present a conceptual diagram relating plant and soil biodiversity with soil structure and water and nutrient use efficiencies as a framework for future studies. We then consider how cropping systems design and management are interrelated and how management options might be interfaced with farmers' knowledge in taking management decisions. Finally, we attempt to express some economic benefits of soil biodiversity to society as part of a wider strategy of conserving and using agrobiodiversity.

PLoS Biology: Switching Drugs for Livestock May Help Save Critically Endangered Asian Vultures

2006-03-15T08:22:55-00:00

Extirpating the Agriculture versus Conservation Dichotomy.

2006-01-24T07:46:32-00:00

Conservation Biology, Vol. 20, pp. 253-254.

Conservation, Human Rights, and Poverty Reduction

2006-01-24T07:42:49-00:00

Conservation Biology, Vol. 20 (2006), pp. 250-252.

Preventing Micronutrient Malnutrition

2006-01-10T13:17:40-00:00

(1997)

The burden of food related ill health in the UK

Mike Rayner — 2005-11-16T10:19:43-00:00

J Epidemiol Community Health, Vol. 59, No. 12. (1 December 2005), pp. 1054-1057.

Study objective: To quantify the burden of ill health in the UK that can be attributed to food (the burden of food related ill health). Design: Review and further analysis of the results of work concerned with estimates of the burden of disease measured as morbidity, mortality, and in financial terms and with the proportion of that burden that can be attributed to food. Main results: Food related ill health is responsible for about 10% of morbidity and mortality in the UK and costs the NHS about pound6 billion annually. Conclusions: The burden of food related ill health measured in terms of mortality and morbidity is similar to that attributable to smoking. The cost to the NHS is twice the amount attributable to car, train, and other accidents, and more than twice that attributable to smoking. The vast majority of the burden is attributable to unhealthy diets rather than to food borne diseases.

Planting the seeds of a new paradigm.

MA Matzke — 2005-08-08T14:00:55-00:00

PLoS Biol, Vol. 2, No. 5. (May 2004)

Diversity decreases invasion via both sampling and complementarity effects

Joseph Fargione — 2005-05-27T05:44:38-00:00

Ecology Letters, Vol. 8, No. 6. (June 2005), pp. 604-611.

Novel genetic basis of field-evolved resistance to Bt toxins in Plutella xylostella

S Baxter — 2005-05-25T04:24:49-00:00

Insect Molecular Biology, Vol. 14, No. 3. (June 2005), pp. 327-334.

Genetic diversity and disease control in rice

Youyong Zhu — 2005-08-08T08:55:32-00:00

Nature, Vol. 406 (17 August 2000), pp. 718-722.

Crop heterogeneity is a possible solution to the vulnerability of monocultured crops to disease. Both theory and observation indicate that genetic heterogeneity provides greater disease suppression when used over large areas, though experimental data are lacking. Here we report a unique cooperation among farmers, researchers and extension personnel in Yunnan Province, China—genetically diversified rice crops were planted in all the rice fields in five townships in 1998 and ten townships in 1999. Control plots of monocultured crops allowed us to calculate the effect of diversity on the severity of rice blast, the major disease of rice. Disease-susceptible rice varieties planted in mixtures with resistant varieties had 89% greater yield and blast was 94% less severe than when they were grown in monoculture. The experiment was so successful that fungicidal sprays were no longer applied by the end of the two-year programme. Our results support the view that intraspecific crop diversification provides an ecological approach to disease control that can be highly effective over a large area and contribute to the sustainability of crop production.

Mitigation of HIV/AIDS- impacts through agricultural and rural development - success stories and future actions

2005-03-07T09:02:16-00:00

This report, produced by the Southern African Regional Poverty Network (SARPN), summarises the findings of a May 2003 workshop on mitigating the impacts of HIV and AIDS through agriculture and rural development. The workshop explored experiences in a number of areas, including: enhancing livelihood resilience at farm household level, agrobiodiversity and indigenous knowledge in the mitigation of the consequences of HIV and AIDS, mitigation of the impact of HIV and AIDS on rural Livelihoods through low-labour input agriculture and related activities, and action oriented HIV and AIDS research issues. Key findings included the following: development, relief and rehabilitation must be addressed together; policy should encourage and be influenced by local implementation; better targeting and participation help affected people take charge; and greater focus is needed on multi-sectoral partnerships at district and village level. The workshop also identified the need to move beyond “labour saving” technologies and practices to using a labour management approach, which includes spreading labour demands over time to minimise work load at peak periods. Finally, the report calls for both policy and practice to be based on experimentation and evidence of success. [adapted from authors]

Analysis of food composition data on rice from a plant genetic resources perspective

Gina Kennedy — 2005-02-25T11:15:34-00:00

Food Chemistry, Vol. 80, No. 4. (April 2003), pp. 589-596.

Rice accounts for 21, 14 and 2% of global energy, protein and fat supply, respectively. There are thousands of different rice varieties; some have been in the diet for centuries, while others are new hybrids promoted for qualities such as high yield and drought and disease resistance. Little is known about the nutrient composition of many of the world's rice varieties. This paper investigates the literature on nutrient composition of rice varieties. Standardization of data to 100 g samples of unpolished rice (dry matter basis), showed intra-varietal ranges of; 9 g protein, 5.65 mg iron, 3.34 mg zinc, 1.6 mg thiamin, 0.392 mg riboflavin and 7.2 mg niacin. Currently, several research institutions are working toward improving the nutrient content of rice through greater utilization of rice genetic resources. The results section discusses in detail the magnitude of intra-varietal differences and highlights practical applications of genetic diversity in rice.

Carotenoid Content in Different Varieties of Pumpkins

M Murkovic — 2004-12-28T16:57:07-00:00

Journal of Food Composition and Analysis, Vol. 15, No. 6. (December 2002), pp. 633-638.