Journal of Agriculture and Rural Development in the Tropics and Subtropics (JARTS)
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Decomposition of Organic Substrates and their Effect on Mungbean Growth in Two Soils of the Mekong Delta
Get PDFAgricultural land use in the Mekong Delta of Vietnam is dominated by intensive irrigated rice cropping systems on both alluvial and acid sulfate soils. A stagnating and occasionally declining productivity may be linked on the alluvial soils to low N use efficiency and low soil organic matter content while on acid sulfate soils to acidity, Al toxicity and P deficiency. For economic reasons, farmers increasingly diversify their cropping system by replacing the dry season rice by high-value horticultural crops grown under upland conditions. However, upland cropping is likely to further exacerbate the soil-related problems. Organic substrates from decentralized waste and waste water management are widely available and may help to alleviate the reported soil problems. During the dry season of 2003/2004, the effect of the application of various types and rates of locally available waste products on crop performance was evaluated at both an alluvial and an acid sulfate soil site. The C and N mineralization dynamics of nine organic substrates from waste and waste water treatment were determined by anaerobic (N) and aerobic (C) incubation in the laboratory. The response of 12 week-old mungbean (dry matter accumulation) to substrate application (1.5 – 6.0 Mg ha−1) was evaluated on a degraded alluvial and on an acid sulfate soil. In the alluvial soil, largest mineralization rates were observed from anaerobic sludge. Biomass increases in 12 week-old mungbean ranged from 25-98% above the unfertilized control. In the acid sulfate soil, highest net-N release rates were observed from aerobic composts with high P content. Mungbean biomass was related to soil pH and exchangeable Al3+ and was highest with the application of aerobic composts. We conclude that the use of organic substrates in the rice-based systems of the Mekong Delta needs to be soil specific
Green Gram Rotation Effects on Maize Growth Parameters and Soil Quality in Myanmar
Get PDFAt present maize–green gram crop rotations are not widely practiced among farmers in Myanmar. However, this cropping system might become more popular in the future given raising prices for green gram and maize grain and scarcity of mineral nitrogen (N) fertilizers in this Asian country. The results of a cropping systems experiment with continuous maize versus a green gram-maize rotation, manure application (0 and 2 t ha−1) and phosphorus (P) fertilization (0 and 15 kg P ha−1) in each of five consecutive seasons revealed a strong decline in total dry matter and grains yields for both crops irrespective of the treatment. Treatment effects on yield components, nutrient concentrations, mycorrhizal infection and nematode infestation were small or negligible. The data show that in addition to manure used at 2 t ha−1, application of mineral N fertilizers is essential to maintain particularly maize yields. A comparison of different green gram cultivars did not indicate genotype specific effects on maize growth. The incorporation of legume residues, unless they are used as animal feed, is recommended to increase the recycling of N and to balance N fluxes when green gram is cultivated for seed
Vernacular Languages and Cultures in Rural Development: Theoretical Discourse and Some Examples
Get PDFThe role of language and culture in rural development projects is investigated. Examples taken from the context of Northern Iran, the significance of which is not confined to its agricultural and forestry resources and extends beyond national borders, are presented. A starting point of the analysis is an appreciation of diversity, not only in the biological, but also in the cultural sense, as an asset and viewing development endeavors as sense making acts. It is further argued that new intangible forms of capital are increasingly gaining in importance in the contemporary world. Capital is considered not merely as an asset, but as a relation having accumulation moment as well, and impact on the regeneration of cultural and economic divides. A central concern is enhancing social inclusion and promoting conditions for making voices of otherness heard. It is deemed that vernacular voices encompass valuable indigenous knowledge and modes of perception, the negligence of which can undermine the success of rural development projects
Factors Influencing Irrigation Technology Adoption and its Impact on Household Poverty in Ghana
Get PDFThe treadle pump technology was promoted and disseminated as an alternative to traditional rope and bucket for irrigation in Ghana by the International Non-Governmental Organization, Enterprise Works. The aim is to improve output, increase incomes and consequently reduce poverty among farm households. The paper employed the Heckman two-stage and the Ordinary Least Square procedures to identify the factors that influence adoption of the technology and the impact of adoption on the poverty status of farm households. Farm and household level data were obtained from 108 farmers consisting of 52 adopters and 58 non-adopters. The results demonstrated that availability of labor and increases in number of extension visits per year are factors that increase the probability of adoption. The results also showed that increase in irrigated area has the highest impact on poverty followed by adoption of treadle pump and literacy level of farmers
Investigation of Imperata sp. as a Primary Feedstock for Compost Production in Ucayali region, Peru
Get PDFFive compost piles with different initial C : N ratios have been investigated in this study. As a primary feedstock Imperata sp. was used. The primary feedstock was mixed with poultry litter and vegetable refuse in order to obtain different C : N ratio. The results show that during 64 days of well managed composting under tropical conditions the initial C : N ratio between 30:1 and 50:1 decreased to ratio 11:1 to 15:1, respectively. Results of bioassay tests expressed as the germination index (GI) indicate particular compost phytotoxicity. The value of GI was 51.4%, 48.6%, 47.8%, 46.7% and 40.0% for samples from the compost with initial C : N ratios of 30:1, 37:1, 40:1, 44:1 and 50:1, respectively
Phosphate Sorption Characteristics and External P Requirements of Selected South African Soils
Get PDFThe Transkei is the largest consolidated area in South Africa where land is held by smallholder farmers but little is known about the extent of phosphate fixation in the region. This study was conducted to determine the phosphate sorption properties and external P requirements (EPR) of selected soils from the Transkei region, South Africa and to relate derived sorption values to selected soil parameters. The P sorption maxima and EPR values varied widely ranging from 192.3 to 909.1 mg P kg−1 and from 2 to 123 mg P kg−1−1 soil, respectively. Citrate dithionite bicarbonate-extractable aluminum explained most of the observed variations in P sorption. About 43% of the soils were found to be moderate P fixers and may need management interventions to ensure adequate P availability to crops. The single point sorption index accurately predicted the EPR of the soils obviating the need to use multiple point sorption isotherms. The results suggested that the use of blanket phosphate fertilizer recommendations may not be a good strategy for the region as it may lead to under-application or over-application of P in some areas
Interaction between Coffee (Coffea arabica L.) and Intercropped Herbs under Field Conditions in the Sierra Norte of Puebla, Mexico
Get PDFCaffeine released from decaying seeds and leaves accumulates in a soluble form in the soil. The compound is known to inhibit mitosis, reduce the access of nutrients and water to surrounding plants which is one of limiting problems in intercropped coffee plantations. The allelopathic interactions between coffee (Coffea arabica L.) and mint (Mentha piperita L.), basil (Ocimum basilicum L.), oregano (Origanum vulgare L.) and sage (Salvia officinalis L.) could be a diversification alternative and extra income activity for coffee growers outside the harvest period that could cope with high levels of caffeine in the soil. We tested the interaction of the proposed system (2004 – 2005) in rural area of Puebla State, Mexico. The results demonstrate that intercropping sage, spearmint, basil and oregano stimulate the plagiotropic growth of Coffea arabica plants most effectively in young production systems, through volatile essential oils. Intercropping basil, sage, spearmint and oregano in coffee plantations seems to be a promising approach for higher income and increasing yield and quality production in coffee farms
Study on the Effect of Different Urea Fertilizer Rates and Plant Populations on the Severity of Bacterial Blight (BB) of Rice
Get PDFTo study the effect of different urea fertilizer rates and plant populations on disease severity of bacterial blight of rice and yield lasses related to disease, the experiments including three plant populations (110000, 150000, 190000) and five urea fertilizer rates (0,56 lb, 112 lb, 168 lb and 224 lb per acre) were conducted at Central Agriculture Research Institute farm in 1999 and 2000 rainy seasons. Manawthukha was used as a test variety that is susceptible to bacterial blight of rice. The disease severity could be increased by the application of urea. Although urea 112 lb per acre gave moderate disease severity than without urea, its yield is highest. The higher disease severity also showed the related effect of plant population of 150000 and above. However the combination of urea 224 lb per acre with the population of 190000 and 150000 gave the highest severity of bacterial blight disease and the minimum grain yield. The application of urea 224 lbs per acre can cause yield reduction ranging from 18.67 percent to 27.57 percent over the application of urea 112 lb per acre
Economic Impact Assessment for Technology: The Case of Improved Soybean Varieties in Southwest Nigeria
Get PDFThe Study on economic impact assessment for the production of improved soybean varieties in Nigeria was carried out in Nigeria using the agronomic data on yield of the nationally coordinated soybean research from two major zones namely the southwest and the middle belt. The study assesses the economic returns due to improved soybean varieties. Primary data were collected with the use of structured and validated questionnaires. A sample of 288 respondents was drawn from four states namely Oyo, Ogun, Kwara and Niger State at 72 respondents per state. Secondary data were collected from Agricultural Development Programme (ADP), International Institute for Tropical Agriculture (IITA), Institute of Agricultural Research and Training, (IAR T), National Cereals Research Institute (NCRI), Central Bank of Nigeria CBN and Federal Office of Statistics (FOS). An internal rate of return (IRR) of 38 percent was estimated from the stream of netted real social gains at 1985 constant. The return to investment in soybean production technology is attractive and justifies the investments made on the technologies. The policy implication is that there is underinvestment in soybean production research
Assessment of Structural Traits and Management Related to Dairy Herds in the Peri-urban Area of Bobo Dioulasso (South West of Burkina Faso)
Get PDFTo define mean herd size, structural traits, animal sourcing and use, management and aspects related to the milk production, 118 dairy herds, involved in a FAO dairy development project were studied. The mean herd size after allocation to clusters: Small (≤38 heads), Medium (38, ≤61 heads) and Large (61 heads) was 52.8±25.8, ranging from 7 to 134 heads of cattle. The following genotypes: Cross bred (CR) 58.8%, Zebu (ZB) 23.2% and Taurine cattle (TA) 18.0% which were not uniformly distributed neither across nor within herds were identified. Sex ratio was two thirds of females (70.6%), one third of males (28.1%) and a low proportion (1.3%) of castrated males. No mature TA males compared to 53.3% of the male ZB and 31.4% of the male CR, were indicated as potential sires. Investments in purchase of animals were higher in Small than in Medium and Large herds; of all purchased sires 53.8% were found in Small herds vs. 28.2% and 18.0% in Medium and Large. Herd property was equally distributed between single (56.8%) and multi property (43.2%). There was more manpower available per 100 cows in Small, being almost double and triple than in Medium and Large herds. Although milk extracted, was similar in all clusters averaging 2.4±0.5 litres/day/cow, milk off take rate, due to higher proportion of lactating cows, appeared higher in Small herds