BIOLOGICAL NITROGEN-FIXATION FOR SUSTAINABLE AGRICULTURE - A PERSPECTIVE
BIOLOGICAL NITROGEN-FIXATION FOR SUSTAINABLE AGRICULTURE - A PERSPECTIVE
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DOI：
10.1007/bf00011307
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发表时间：
1992-03-01
期刊：
影响因子：
4.9
通讯作者：
GEORGE, T
中科院分区：
文献类型：
--
作者：
BOHLOOL, BB;LADHA, JK;GEORGE, T
在农业中大量使用化学氮肥的经济和环境成本是全球关注的问题。可持续性的考虑要求必须迫切寻求氮肥的替代品。生物固氮（BNF）是一种将大气中的氮转化为植物可用形式的微生物过程，提供了这种替代方案。固氮系统提供了一种经济上有吸引力和生态上无害的减少外部投入和改善内部资源的手段。豆科植物和根瘤菌等共生系统是大多数种植系统中氮素的主要来源，红萍和鱼腥藻等共生系统对水稻具有特殊的价值。联合和自由生活的微生物的固氮作用也很重要。然而，科学和社会文化制约因素限制了生物固氮系统在农业中的应用。虽然已经研究了影响生物固氮的几个环境因素，但关于生物体如何对特定情况作出反应仍然存在不确定性。在豆科植物的情况下，生态模型，预测的可能性和规模的反应根瘤菌接种现在变得可用。分子生物学使人们有可能将选择属性引入固氮生物体，但对它们如何与环境相互作用的有限知识使得很难定制生物体。在田间检测引入的生物体的困难仍然是评估接种成功或失败的主要障碍。生产层面的问题和社会文化因素也限制了生物固氮系统与实际耕作情况的结合。只有通过分析和解决生物固氮在田间的主要制约因素以及农民采用和使用该技术，才能实现最大效益。
The economic and environmental costs of the heavy use of chemical N fertilizers in agriculture are a global concern. Sustainability considerations mandate that alternatives to N fertilizers must be urgently sought. Biological nitrogen fixation (BNF), a microbiological process which converts atmospheric nitrogen into a plant-usable form, offers this alternative. Nitrogen-fixing systems offer an economically attractive and ecologically sound means of reducing external inputs and improving internal resources. Symbiotic systems such as that of legumes and Rhizobium can be a major source of N in most cropping systems and that of Azolla and Anabaena can be of particular value to flooded rice crop. Nitrogen fixation by associative and free-living microorganisms can also be important. However, scientific and socio-cultural constraints limit the utilization of BNF systems in agriculture. While several environmental factors that affect BNF have been studied, uncertainties still remain on how organisms respond to a given situation. In the case of legumes, ecological models that predict the likelihood and the magnitude of response to rhizobial inoculation are now becoming available. Molecular biology has made it possible to introduce choice attributes into nitrogen-fixing organisms but limited knowledge on how they interact with the environment makes it difficult to tailor organisms to order. The difficulty in detecting introduced organisms in the field is still a major obstacle to assessing the success or failure of inoculation. Production-level problems and socio-cultural factors also limit the integration of BNF systems into actual farming situations. Maximum benefit can be realized only through analysis and resolution of major constraints to BNF performance in the field and adoption and use of the technology by farmers.