Water scarcity in certain regions of sub-Saharan Africa impacts agricultural production while prolonging dry seasons, and contributing to food insecurity and malnutrition. The objectives of the study were to evaluate ...Water scarcity in certain regions of sub-Saharan Africa impacts agricultural production while prolonging dry seasons, and contributing to food insecurity and malnutrition. The objectives of the study were to evaluate the nutritional yield (edible yield × nutritional content) of indigenous leafy vegetables commonly consumed in Africa under water-stressed conditions. Two species of amaranth, two species of African nightshade, and two varieties of Ethiopian kale were examined under environment-controlled water-sufficient and water-deficient conditions. Fresh and dry stem and leaf weights significantly decreased in the three crop groups under the water-deficient treatment. Nutritional values for carotenoids, tocopherols, calcium and zinc showed significant differences at the content level among treatments. Among the 6 crops evaluated, the amaranth species named Amaranthus hypochondriacus and the African nightshade species named Solanum scabrum had the lowest nutrient losses in drought conditions.展开更多
Research carried out to assess the impact of open-pollinated Tomato leaf curl virus（ToLCV）-resistant tomatoes and hybrids on the livelihoods of resource-poor farmers in Southern India is described and discussed.Thre...Research carried out to assess the impact of open-pollinated Tomato leaf curl virus（ToLCV）-resistant tomatoes and hybrids on the livelihoods of resource-poor farmers in Southern India is described and discussed.Three high-yielding ToLCV-resistant tomato varieties were developed initially using conventional breeding and screening techniques involving inoculation by ToLCV-viruliferous whitefly,Bemisia tabaci.In 2003 and 2004,respectively,these varieties were released officially by the Karnataka State Seed Committee and the Indian Ministry of Agriculture through notification in the Gazette of India.From 2003 to 2005,eleven seed companies bought breeder seed of the ToLCV-resistant varieties and used them to begin breeding F1 hybrids from them.Socio-economic studies carried out to assess the benefits obtained from growing the ToLCV-resistant varieties found that farmers could gain up to 10 times the profit by growing the ToLCV-resistant varieties compared to the pre-existing ToLCV-susceptible varieties.Adoption of ToLCV-resistant tomatoes was also associated with reduced pesticide use.Extra income from tomato sales was prioritised by farmers to pay for children＇s education,better nutrition and medicines.In a joint effort with the commercial seed sector in India,a promotional field day was organised in 2007.As well as the three ToLCV-resistant varieties,62 ToLCV-resistant hybrid tomatoes were exhibited during a farmer-field day by 17 commercial seed companies and several public institutes.Tomatoes with ToLCV-resistance are now grown widely in South India and seeds of the three open-pollinated varieties have been distributed to more than 12 countries.In 2007,a conservative estimate of the financial-benefit to cost of the research ratio was already more than 837：1.展开更多
Increasing foreign exchange problems and deteriorating prices of traditional exports have led policy makers and donor agencies to seek diversification in export crop production. In Ghana, crops such as pineapples and ...Increasing foreign exchange problems and deteriorating prices of traditional exports have led policy makers and donor agencies to seek diversification in export crop production. In Ghana, crops such as pineapples and mangoes appear promising because of their high labour intensity and expanding demand for fruits in Europe. Notwithstanding, there is a possible trade-off between export and food crop production because of the possibility of resource re-allocation. So far the major concern of government has been the growth in export earnings while the micro-level distributional effects remain under-investigated. The study focused on a household survey undertaken in the forest and coastal-savannah transition zones, where the farming system has undergone transition from an established food-crop farming for urban markets to an intensive production of horticultural products for export. Logistic regression and Gini coefficient approaches were used to estimate the determinants of household food availability and income distribution respectively. Though, households engaged in export horticulture appear better-off than those that do not, the sole adoption of either staple or export crop is not sufficient for improving food availability. Consequently, linkages which allow simultaneous and reliably access to equitable distribution of resources and services are critical for household survival in competitive global food markets展开更多
文摘Water scarcity in certain regions of sub-Saharan Africa impacts agricultural production while prolonging dry seasons, and contributing to food insecurity and malnutrition. The objectives of the study were to evaluate the nutritional yield (edible yield × nutritional content) of indigenous leafy vegetables commonly consumed in Africa under water-stressed conditions. Two species of amaranth, two species of African nightshade, and two varieties of Ethiopian kale were examined under environment-controlled water-sufficient and water-deficient conditions. Fresh and dry stem and leaf weights significantly decreased in the three crop groups under the water-deficient treatment. Nutritional values for carotenoids, tocopherols, calcium and zinc showed significant differences at the content level among treatments. Among the 6 crops evaluated, the amaranth species named Amaranthus hypochondriacus and the African nightshade species named Solanum scabrum had the lowest nutrient losses in drought conditions.
基金funded by the Department for Interna-tional Development,UK(DFID project codes R6627,R7460,R8247(Crop Protection Programme)and Phase Ⅲ of the International Whitefly Project)
文摘Research carried out to assess the impact of open-pollinated Tomato leaf curl virus（ToLCV）-resistant tomatoes and hybrids on the livelihoods of resource-poor farmers in Southern India is described and discussed.Three high-yielding ToLCV-resistant tomato varieties were developed initially using conventional breeding and screening techniques involving inoculation by ToLCV-viruliferous whitefly,Bemisia tabaci.In 2003 and 2004,respectively,these varieties were released officially by the Karnataka State Seed Committee and the Indian Ministry of Agriculture through notification in the Gazette of India.From 2003 to 2005,eleven seed companies bought breeder seed of the ToLCV-resistant varieties and used them to begin breeding F1 hybrids from them.Socio-economic studies carried out to assess the benefits obtained from growing the ToLCV-resistant varieties found that farmers could gain up to 10 times the profit by growing the ToLCV-resistant varieties compared to the pre-existing ToLCV-susceptible varieties.Adoption of ToLCV-resistant tomatoes was also associated with reduced pesticide use.Extra income from tomato sales was prioritised by farmers to pay for children＇s education,better nutrition and medicines.In a joint effort with the commercial seed sector in India,a promotional field day was organised in 2007.As well as the three ToLCV-resistant varieties,62 ToLCV-resistant hybrid tomatoes were exhibited during a farmer-field day by 17 commercial seed companies and several public institutes.Tomatoes with ToLCV-resistance are now grown widely in South India and seeds of the three open-pollinated varieties have been distributed to more than 12 countries.In 2007,a conservative estimate of the financial-benefit to cost of the research ratio was already more than 837：1.
文摘Increasing foreign exchange problems and deteriorating prices of traditional exports have led policy makers and donor agencies to seek diversification in export crop production. In Ghana, crops such as pineapples and mangoes appear promising because of their high labour intensity and expanding demand for fruits in Europe. Notwithstanding, there is a possible trade-off between export and food crop production because of the possibility of resource re-allocation. So far the major concern of government has been the growth in export earnings while the micro-level distributional effects remain under-investigated. The study focused on a household survey undertaken in the forest and coastal-savannah transition zones, where the farming system has undergone transition from an established food-crop farming for urban markets to an intensive production of horticultural products for export. Logistic regression and Gini coefficient approaches were used to estimate the determinants of household food availability and income distribution respectively. Though, households engaged in export horticulture appear better-off than those that do not, the sole adoption of either staple or export crop is not sufficient for improving food availability. Consequently, linkages which allow simultaneous and reliably access to equitable distribution of resources and services are critical for household survival in competitive global food markets
