TOWARDS FERTILISERS FOR IMPROVED UPTAKE BY PLANTS

摘要

Meeting human needs within the ecological limits of our planet calls for continuous reflection on and redesigning of our agricultural practices. Several transformations that drastically changed the course of agriculture have been realised over the past century including dramatic increases in yields, reduced labour requirement, optimised use efficiency of inputs and chain logistics, and spatial integration of agricultural and natural functions within the landscape, caused by driving forces such as growing ecological insights, technological innovations and societal change. The discovery and use of mineral fertilisers has been one of the driving forces for increased crop yields and agricultural productivity. These benefits come however at an environmental cost and have not yet been effectively used to lift many poor farmers out of poverty. Any unbalanced composition of nutrients contained in fertilisers could also cause reduced nutritional quality of crop produce. Agronomic practices to apply existing fertilisers at the right time, the right place, in the right amount, and of the right composition can improve the use efficiency of fertilisers. Yet, the overall progress to reduce the negative side effects is insufficient for the desired transformation in agriculture. There have been no fundamental reflections about the role and functioning of mineral fertilisers over the past four decades or more, and little investment is made in mineral fertiliser research and development. It is for this reason that the Virtual Fertilizer Research Centre was established to foster the creation of the next generation of fertilisers and production technologies in order to help feed the world's growing population and provide sustainable increases in global food production. The centre is virtual in the sense that it comprises the work of multiple research institutions around the world, cooperating to advance a unified research agenda. It is proposed in this paper to more deliberately adopt knowledge of plant physiological processes, including the diversity of mineral nutrient uptake mechanisms, their translocation and metabolism as an entry point in identifying the composition, amount, and timing of nutrients to meet plant physiological needs for improved instantaneous uptake. In addition to the root, efforts should be redoubled with several other avenues, which as of now are at best haphazard, for the delivery of nutrients to the plant. The current surge in nanotechnology could for instance be leveraged to produce or deliver fertilisers in nanoparticle forms. Furthermore, ecological processes including interactions and symbioses with micro-organisms could be exploited to enhance nutrient uptake. This paper reflects on current fertilisers and proposed research and development avenues to arrive at novel fertilisers or delivery mechanism that can leapfrog agro-technical and socio-economic developments. In addition to R&D efforts on fertiliser development, a global dialogue and the engagement of actors from sectors other than the traditional agricultural and environmental sectors will be needed. Given the link between plant fertilisation and nutrition and human nutrition, and the role as input factor in raising agricultural productivity, such actors would include those from the health and medical sector, the food industry, and development organisations.