中国三个杂交稻组合在孟加拉的试验研究

用四川农业大学水稻研究所提供的3个杂交水稻组合QL-081、QL-083和QL-052在孟加拉进行多点品比试验.结果表明,3个组合与孟加拉当地主栽品种相比不仅产量明显提高,而且抗病、无倒伏发生,适于在孟加拉推广.     

The spread of highly pathogenic avian influenza (subtype H5N1) clades in Bangladesh, 2010 and 2011

Since the global spread of highly pathogenic avian influenza H5N1 during 2005–2006, control programs have been successfully implemented in most affected countries. HPAI H5N1 was first reported in Bangladesh in 2007, and since then 546 outbreaks have been reported to the OIE. The disease has apparently become endemic in Bangladesh. Spatio-temporal information on 177 outbreaks of HPAI H5N1 occurring between February 2010 and April 2011 in Bangladesh, and 37 of these outbreaks in which isolated H5N1 viruses were phylogenetically characterized to clade, were analyzed.     

Freshwater prawn farming in Bangladesh: history, present status and future prospects

Within the overall agro-based economy in Bangladesh, freshwater prawn ( Macrobrachium rosenbergii ) farming is currently one of the most important sectors of the national economy. During the last two decades, its development has attracted considerable attention for its export potential. Freshwater prawn farming offers diverse livelihood opportunities for a large number of rural poor. Although the prospects for prawn farming are positive, it requires some research and development activities for long-term sustainability. This paper provides an overview of freshwater prawn farming in Bangladesh.     

Marketing systems of freshwater prawns in three coastal districts of Bangladesh

The present study analyzes the prawn marketing chain before and after the implementation of a Danish-funded project (GNAEP) in three coastal districts of greater Noakhali, southeast region of Bangladesh. The results reveal that, before GNAEP, there was a longer prawn marketing chain with a number of intermediaries who used to share a considerable amount of market margin. However, after implementation of GNAEP, the prawn marketing chain has become shorter with a significant reduction of intermediaries which facilitates direct selling of prawns to processing plants through local Community Based Organizations (CBOs). The present prawn marketing system in the regions is in favor of prawn farmers. Farmers have greater advantages because 1) CBOs provide reasonable market price and actual weight, 2) CBOs can bargain with processing plants as the former are aware of the latest international market prices through Marketing Information System 3) number of intermediaries is lowered and 4) transport and preservation costs are reduced. The displaced intermediaries, some of whom are powerful persons in the society, have again started to influence the prawn market in different ways. This fact has opened up another discussion on how the power structure is shifting in this region and how they are affecting prawn marketing.     

THE SUSTAINABLE LIVELIHOODS APPROACH TO THE DEVELOPMENT OF FRESHWATER PRAWN MARKETING SYSTEMS IN SOUTHWEST BANGLADESH

A conceptual framework, drawn from an approach to poverty reduction known as the Sustainable Livelihoods Approach (SLA), is applied to understanding the role of freshwater prawn (Macrobrachium rosenbergii) marketing systems in southwest Bangladesh. Freshwater prawn marketing potentially provides economic returns and social benefits to the rural poor. Although the potential benefits are great, a number of constraints were identified for the long-term sustainability of prawn marketing systems. The study used the SLA framework as an analytical tool to identify ways to strengthen livelihoods of prawn traders and associated groups.     

A comparison of development opportunities for crab and shrimp aquaculture in southwestern Bangladesh, using GIS modelling

The present study identifies and quantifies appropriate sites for brackish water aquaculture development in southwestern Bangladesh using remote sensing, GPS and geographical information systems (GIS). A colour composite Landsat TM image from 1996 covering the southwestern part of Bangladesh was used to identify the extent of brackish water and to classify land use. The remotely sensed data were complemented by secondary data digitised from a range of sources, including hard copy maps, to create a spatial database that included environmental and infrastructural data. A series of GIS models were developed in order to identify and prioritise the most suitable areas for brackish water shrimp and crab farming. Using qualitative and quantitative output from the models, the benefits of shrimp and crab farming and alternative land uses in the Khulna region were compared, based on gross production, economic output and employment potential. Comparisons were made of brackish water shrimp and crab culture with moderately saline-tolerant tilapia and prawn culture, freshwater carp culture and traditional rice production systems. Shrimp was identified as the most capital intensive and risky production system. Earnings per hectare were a little higher for shrimp culture than for crab culture. The present study demonstrates the usefulness of GIS as an aquaculture planning tool in a region where natural resources are already under considerable pressure.     

CONSTRAINTS TO THE ADOPTION OF RICE-FISH FARMING BY SMALLHOLDERS IN BANGLADESH: A FARMING SYSTEMS ANALYSIS

In spite of its potential, the adoption of rice-fish farming among smallholders in Bangladesh is low. This paper seeks to explain this low adoption by evaluating the rice-fish technology as one element of the household farming system. The adoption of the technology is associated with a range of technical, human, and institutional constraints. Rice-fish technology is not structured to address the food security goal of smallholders and, therefore, is adopted by only those who are better placed to assume the risks. This paper concludes that the adoption of the technology among this group of smallholders would accelerate when policymakers acknowledge its constraints and structure extension services accordingly.     

孟加拉国曼尼普尔部落对部族药用植物的利用

通过问卷调查的方式,调查了孟加拉国曼尼普尔部落对民族药用植物的利用。发现有26个科29个属32种药用植物用于治疗37种疾病。结果表明：所调查的32种植物中,多利用其地上部分（86％）,而地下部分的利用相对较少（14％）。在植物药用制备中,叶片的使用最高（17个种）,接下来依次是树皮、果实、根／地下茎、整个植株、种子和花。在32个植物种中,用于治疗痢疾的物种有10个,治疗发烧和风湿病的物种各5个,治疗哮喘、便秘、创伤和皮肤病的各4个物种,低烧病、咳嗽、腹泻各3种。32个物种中,72％的药用植物都能治疗至少一种疾病：75％口服使用,9％外服用,16％口服和外服结合使用。本研究突出了民族植物研究的潜力和迫切需求获取药用植物在人类健康利用的健康医疗实践知识。     

SOIL CHARACTERISTICS AND CARBON SEQUESTRATION POTENTIALS OF VEGETATION IN DEGRADED HILLS OF CHITTAGONG,BANGLADESH

The impacts of tree and horticultural plantations, and grassland on soil characteristics in the degraded hills of Chittagong District, Bangladesh are reported on this paper. The carbon sequestration potential and the present value of carbon revenue flow were also estimated for the degraded hills of Chittagong using A. auriculiformis plantations for the purpose. The results showed that the change of land use from degraded hill to vegetation cover had altered the physico‐chemical characteristics of soil in the study area. The organic carbon concentration and storage under vegetated land uses were significantly (p < 0·05) higher than those in the degraded hill areas. The results also showed that about 17 million megagram carbon (MgC) could be sequestered in the degraded hill areas of Chittagong District by planting A. auriculiformis trees in a 15‐year rotation. The present value of revenue flow generated by this sequestration at the current international market carbon price and assuming a realistic market interest rate could be as high as US$ 326 million. The net present value of the revenue stream is expected to be positive. Copyright © 2011 John Wiley & Sons, Ltd.     

Nature Farming with Vesicular-Arbuscular Mycorrhizae in Bangladesh

Summary

Systematic research on the effect of vesicular-arbuscular mycorrhizal fungi with different agricultural crops, sand dune plants and plantation crops has been carried out in Bangladesh for last few years. Large numbers of VA-mycorrhizal fungi have been detected in different soil types for identification and inoculum production and for use in nurseries and the field as an alternative to chemical fertilizers and pesticides and to progress towards nature farming. The VAM fungi not only absorb and translocate immobile nutrients like phosphorus, zinc and copper (especially phosphorus) through external hyphae, but also play important roles in inter- and intra-specific transfer of carbon, phosphorus, and nitrogen from plant to plant. VAM fungi may also protect plants from certain root-infecting pathogens, improve plant-water relations, enhance the establishment and growth of micro-propagated plants, and increase plant tolerance to salinity. VAM fungi can improve the ecological and environmental conditions of the country and its agriculture by reducing the farmer's dependence and expenditure on chemical fertilizers and pesticides. Effective mycorrhizal inoculum can be introduced directly to the field or indirectly through the production of VAM-infected seedlings from nurseries. The gap of knowledge on the occurrence of VAM fungi in association with different agricultural and forest crops is still immense in Bangladesh. This article has been prepared to draw attention of agricultural scientists, plant physiologist, forest managers, policy-makers and different government and non-government officials towards nature farming systems utilizing VAM and possibility of utilizing VAM in production system.