Tropicultura 

About: Tropicultura is an academic journal published by AGRI-OVERSEAS. The journal publishes majorly in the area(s): Agriculture & Crop yield. It has an ISSN identifier of 0771-3312. It is also open access. Over the lifetime, 502 publications have been published receiving 3122 citations.

Cassava Market Participation Decisions of Producing Households in Africa

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

Evaluation of Iron Toxicity on Lowland Irrigated Rice in West Africa

Abstract: Summary In tropical areas, lowland rice (Oryza sativa L.) cultivation (with or without irrigation) is often hampered by iron toxicity. This edaphic stress is common in West African savanna and forest lowlands. It is a nutrient disorder associated with high iron concentrations in the soil solution. The reducing conditions of waterlogged lowland soils boost iron toxicity through solubilization of almost all iron in its ferrous form (Fe 2+ ). This iron toxicity promoting edaphic features of lowland soils depends on the soil and climatic conditions, thus explaining the high spatiotemporal variability. The high quantity of ferrous ions in the soil solution upsets the mineral element balance in the rice and affects its growth. Ferrous iron (Fe 2+ ) is abundantly taken up by the plant and becomes concentrated in the leaves, causing limb discoloration, reduced tillering, stunted growth, while substantially reducing yields. A survey was conducted to quantify the effects of iron toxicity on rice in three countries (Guinea, Ivory Coast and Ghana) in the West African subregion. It was confirmed that iron toxicity is a major edaphic constraint in cultivated lowlands as it affects more than 50% of lowlands and about 60% of cultivated rice plots on average. About 10% of lowland crop fields were even abandoned due to high iron toxicity stress. Studies have also shown that more than 55% of rice-growing areas are affected by excess iron. There is also a significant impact on yield since affected plots were found to have a mean 54% lower yield as compared to healthy plots.

Technology adoption and productivity difference among growers of New Rice for Africa in savanna zone of Nigeria.

Abstract: Summary The use of New Rice for Africa (NERICA) and complementary rice production technology is being promoted by Nigeria government in order to increase productivity of upland rice farming. This study examines the levels, determinants and effects of complementary technology adoption on productivity of NERICA rice farming. Data for the study were obtained from sample survey of 227 NERICA rice farmers in the guinea savanna zone using multistage sampling technique. Data collected were analyzed using Tobit regression model and Cobb-Douglas production function. Results showed that the average technology score was 52.1 percent (+ 0.242). Fifty-five percent of the farmers who scored above the mean were categorized as low technology users. Tobit regression estimation shows that farmers’ technology score was affected significantly (P< 0.05) by farmer’s level of education (0.0127), extension visit (0.0145), farming experience (0.0085), land ownership status (0.0687), credit use (0.0698) and level of rice commercialization (0.3783). Cobb-Douglas production estimation shows a neutrally outward shift in production function as the level of complementary technology increases, indicating increasing productivity. Thus, promotion of complementary technology in NERICA rice production is a worthwhile effort and should continue to be funded. Improvement of those factors that significantly affect adoption of complementary technology is recommended.

Plant secondary metabolites in some medicinal plants of Mongolia used for enhancing animal health and production.

Abstract: Summary The levels and activities of a number of plant secondary metabolites (PSMs) are known to increase in response to increase in stress. The Mongolian plants considered to possess medicinal properties may contain novel compounds since they are exposed to severe conditions; such plants could become good candidates for modern drug discovery programmes. Information on distribution, palatability to livestock and opinion of local people on their nutritive and medicinal values was compiled for 15 plant materials from 14 plant species considered important for medicinal purposes. These plants were evaluated for nutritive value and PSMs: tannins, saponins, lectins, alkaloids and cyanogens. High levels of tannins were found in roots of Bergenia crassifolia and in leaves of B. crassifolia, Vaccinium vitisidaea and Rheum undulatum. High lectin activity (haemagglutination) was present in B. crassifolia roots, and leaves of R. undulatum, Iris lacteal and Thymus gobicus contained weak lectin activity. Tanacetum vulgare, Serratula centauroids, Taraxacum officinale and Delphinum elatum leaves contained saponin activity (haemolysis). Alkaloids and cyanogens were not present in any of the samples. The paper discusses the known medicinal uses of these plants in light of the PSMs levels, and identifies plant samples for future applications in human and livestock health, welfare and safety.