Towards Phosphorus Use Efficiency in Wheat; An Interdiciplinary Research

农业对环境的影响一直是农业和环境科学界关注的主要问题。农业的扩张被认为导致了生物多样性的丧失、栖息地的丧失和对土壤条件的不利影响。农业的集约化可能会导致化肥和杀虫剂对环境的污染、水的退化和能源消耗的增加。例如，自20世纪60年代以来，人类对合成氮肥的使用在全球范围内增加了9倍，而对磷肥的需求增加了两倍。因此，在满足世界未来粮食安全需求的同时，在减少农业对环境的不利影响方面取得进展是一项全球性挑战。 小麦(Triticum astivum L.)是世界范围内的重要农作物，安大略省的年产量为190万公吨，是安大略省和加拿大经济的重要贡献者。考虑到安大略省90%以上的小麦作物是冬季种植的，因此，它作为种植制度的一个组成部分，与其他作物轮作，发挥着非常重要的作用，这不仅为种植制度提供了多样性，而且在冬季提供了土壤覆盖。 磷是植物生长发育所必需的、不可替代的宏观营养物质之一，作物生产严重依赖磷。磷肥是从磷矿中生产的，磷矿是一种有限的资源，据估计，在未来50年至最长400年内，全球范围内磷矿将耗尽。因此，需要大幅减少磷的流失，避免未来的磷危机，这是一个重要的全球关切。磷利用效率(PUE)提高的作物品种被认为对磷资源的可持续利用做出了重大贡献。本项目将尝试采取多学科的方法，以帮助更好地了解小麦PUE的机制。这些机制可能包括，但不限于，增加磷指控的根结构，帮助从稀少的可用池塘中开采磷的根分泌物，如磷酸酶，以及改善PUE以产生更多干物质和单位磷吸收的产量。这项研究将1)研究和剖析根的形态性状，确定影响较高PUE的简单和可遗传的性状，2)为与PUE相关的生理和形态性状开发改进的表型策略，3)在磷有效性有限的现实田间条件下确定优越的表型，4)确定小麦基因组中与磷的有效利用有关的区域，以及5)在已确定的基因组区域中识别和表征候选基因的表达。

The environmental impacts of agriculture have been a major concern among the agricultural and environmental scientific communities. The expansion of agriculture is thought to have resulted in loss of biodiversity, loss of habitat and adverse impact on soil condition. The intensification of agriculture may contribute to environmental pollution by chemical fertilizers and pesticides, degradation of water, and increased energy use. As an example since the 1960s, human use of synthetic nitrogen fertilizer has increased 9 fold, globally, while demand for phosphorus fertilizers has tripled. Therefore, meeting the world’s future food security needs, while making progress towards reducing the adverse environmental impacts of agriculture is a global challenge. Wheat (Triticum asetivum L.) is an important crop, world-wide, and with 1.9 million metric tonnes of annual production in Ontario, an important contributor to Ontario and Canadian economy. Considering that more than 90 % of the wheat crop in Ontario is winter-grown, it therefore plays a very important role as an integral part of the cropping system, in rotation with other crops, which not only offers diversity in the cropping system but also provides soil cover during the winter. Phosphorus is among the essential and un-substitutable macro-nutrients for plant growth and development, on which crop production is heavily dependent. Phosphorus fertilizers are manufactured from phosphorus rock which is a finite resource, estimated to be depleting, on a global scale, in the next 50 to a maximum of 400 years. Therefore, the need to significantly reduce phosphorus losses and to avert a future phosphorus crisis is an important global concern. Varieties of crops with improved Phosphorus use efficiency (PUE) are believed to make a significant contribution to the sustainable use of phosphorus resources. This project will attempt to take a multi-disciplinary approach to contribute to a better understanding of mechanisms of PUE in wheat. These mechanisms may involve, but are not limited to root structures that increase accusation of phosphorus, root exudates such as phosphatases that assist in mining phosphorus from the sparingly available pools, and improved PUE to produce more dry matter and yield per unit of phosphorus uptake. This research will 1) study and dissect root morphological traits and identify simple and heritable traits influencing higher PUE, 2) develop improved phenotyping strategies for physiological and morphological traits related to PUE, 3) identify superior phenotypes under realistic field conditions with limited phosphorus availability, 4) identify regions in the wheat genome that contribute to an fficient use of phosphorus, and 5) identify and characterize the expression of candidate genes in the identified genomic regions.