面对人口的爆炸式增长,长期以来育种的首要目标是高产,推动水稻第一次绿色革命的矮秆育种,使之能在大量施用化肥情况下,植株不会过高而造成倒伏,从而在高肥下获得较高产量。然而,长期高肥下的育种导致一些重要基因资源的丢失,以致主栽水稻品种肥料利用效率普遍较低。因此,对于未来的可持续农业而言,提高作物的氮利用效率至关重要。2021年1月6号,Nature杂志在线发表了来自中科院遗传与发育生物学研究所储成才课题组题为“Genomic basis of geographical adaptation to soil nitrogen in rice”的研究论文,该研究表明水稻的氮利用效率的遗传基础与当地土壤的适应性相关,揭示了氮素调控水稻分蘖发育过程的分子基础。该研究是该领域里程碑式的工作进展,对未来培育施氮肥少而高产的水稻奠定了基础。
综上所述,该研究表明OsTCP19中的等位基因变异有助于水稻对当地土壤氮的地理适应。野生稻中OsTCP19-H的高等位基因频率表明,OsTCP19-H在氮含量通常较低的自然土壤中经历了自然选择。在不同地理位置的水稻驯化期间,田间土壤中的氮含量可能差异很大。在缺氮区域中,OsTCP19-H在低氮的选择压力下保留,而在富氮区域中,OsTCP19-H丢失。将这一氮高效变异重新引入现代水稻品种,在氮素减少的条件下,水稻氮肥利用效率可提高20-30%,也就是说,在水稻生产中,使用更少的化肥,也能达到相同的产量。附:植物学界著名科学家对该工作对评价著名植物研究中心JIC的所长Dale评价:This is truly ground-breaking work, and the study is beautifully-conducted.This work will have implications not only for basic understanding of how plants/rice works, but also enormous implications for reducing fertiliser use.德国著名氮营养学家Nicolaus von Wiren 评论:I am really fascinated by your story and liked it from the beginning, not only because of the uncovered regulatory module but also due to the association of the OsTCP19-H allele with low soil N. Actually, this makes a lot of sense and shows the potential of digging out such genetic variation for improving germplasm.德国马普分子植物生理所 Alisdair Fernie教授评论:“这项发现本身非常令人兴奋,而且作者证明了OsTCP19等位基因多样性与水稻地理分布相关,使得这项工作更具吸引力(Whilst these findings in themselves were highly exciting the fact that the authors were able to demonstrate that OsTCP19 allelic diversity was associated with rice geographic distribution rendered the work fascinating)”“这一出色研究告诉我们,通过重新追溯我们的育种历史,并理解现代集约化农业的适应性改良,可以找到一种减少化肥投入但不牺牲粮食产量的解决方案(As such this fantastic study highlights how retracing our steps and understanding adaptation to the intensive agriculture that characterizes modern agriculture may represent one solution towards minimizing agricultural inputs without compromising yield security or even – as this example proves- enhancing yields)”。