Strategies to improve nitrogen use in forage crops

氮素利用效率是全世界农业面临的主要问题。我们现在有许多分子工具来以新的方式解决这个重要的问题。牧草和豆科作物在叶冠完全形成时收获，干燥的材料是动物饲料的重要蛋白质来源。饲料作物种植者面临的挑战是在减少化肥投入的情况下维持蛋白质生产，以满足新的立法要求。作物蛋白质含量取决于植物在收获前获得足够的氮素。叶N以营养储存蛋白的形式储存，这是一种特殊类型的细胞液泡。过量的氮也可以以硝酸盐的形式储存在液泡中。在饲料作物中，这些氮素储存形式对氮素利用效率和干燥产品的最终饲料价值都很重要。这项研究将探索优化饲料作物氮肥使用和蛋白质生产的方法。通过与模式植物的合作，已经确定了一些营养储存蛋白、液泡类型和作物氮素状况的标记基因，这些基因将在这些饲料作物中进行测试。这些分子标记将在一系列不同环境和管理做法下收集的现场样本中进行测试。田间采样制度还可以包括筛选一些可用于改变植物N储存池的天然化合物。在这些田间试验中也有机会使用一种新型的土壤N传感器来检查供应对N储存池的影响。

Nitrogen (N) use efficiency is a major issue for agriculture across the world. We now have many molecular tools to address this important topic in new ways. Grass and legume forage crops are harvested when the leaf canopy is fully established and the dried material is an important protein source for animal feed. The challenge for the growers of forage crops is to maintain the protein production with decreased fertilizer inputs to meet new legislation requirements. Crop protein content depends on the plant receiving sufficient N until harvest. Leaf N is stored as vegetative storage protein a specialised type of cell vacuole. Excess N can also be stored as nitrate in the vacuole. In forage crops these N storage forms are important for both N use efficiency and the final feed value of the dried product. This research will investigate ways to optimise N fertilizer use and protein production in forage crops.Work with model plants has identified some marker genes for vegetative storage proteins, vacuole type and the crop N status that will be tested in these forage crops. These molecular markers will be tested in field samples collected under a range of different environments and management practices. The field sampling regimes can also include the screening of some natural compounds that can be applied to alter plant N storage pools. There is also an opportunity to use a new type of soil N sensor in these field experiments to check the influence of supply on N storage pools.