Engineering phosphorus metabolism in plants to produce a dual fertilization and weed control system

Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Irapuato, Guanajuato, México.
Nature Biotechnology (Impact Factor: 41.51). 08/2012; 30(9). DOI: 10.1038/nbt.2346
Source: PubMed


High crop yields depend on the continuous input of orthophosphate (PO(4)(-3))-based fertilizers and herbicides. Two major challenges for agriculture are that phosphorus is a nonrenewable resource and that weeds have developed broad herbicide resistance. One strategy to overcome both problems is to engineer plants to outcompete weeds and microorganisms for limiting resources, thereby reducing the requirement for both fertilizers and herbicides. Plants and most microorganisms are unable to metabolize phosphite (PO(3)(-3)), so we developed a dual fertilization and weed control system by generating transgenic plants that can use phosphite as a sole phosphorus source. Under greenhouse conditions, these transgenic plants require 30-50% less phosphorus input when fertilized with phosphite to achieve similar productivity to that obtained by the same plants using orthophosphate fertilizer and, when in competition with weeds, accumulate 2-10 times greater biomass than when fertilized with orthophosphate.

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    • "Our results are in agreement with earlier studies that have provided evidence of a lack of a stimulating effect of Pi/Phi combinations on the growth and development of plants, and it has been clearly demonstrated that plants are unable to metabolize Phi [53] [54] [55] [56] [57]. The only way that plants can use Phi as a P source is through the expression of a bacterial phosphite dehydrogenase, as was recently demonstrated for Arabidopsis thaliana and Nicotiana tabacum [58]. The implementation of the novel fertilization and weed control system based on transgenic plants capable of using Phi as a sole P source will implicate an increased use of Phi in agriculture, stimulating concern regarding effects on microalgae and marine species. "
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    • "Reserve estimates for phosphate rock have recently been revised substantially upward [6]. Furthermore, there is always potential for adaptive responses of technology (such as nutrient recovery or crop biotechnology approaches) and market systems to emerging geological scarcity [7]–[9]. Nevertheless, converging trends suggest that the fertilizer/food system will come under increased pressure in coming decades. "
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