Lambers Hans, Shane Michael W, Cramer Michael D, Pearse Stuart J, Veneklaas Erik J
School of Plant Biology, Faculty of Natural and Agricultural Sciences, The University of Western Australia, 35 Stirling Highway, WA 6009, Australia.
Ann Bot. 2006 Oct;98(4):693-713. doi: 10.1093/aob/mcl114. Epub 2006 Jun 12.
Global phosphorus (P) reserves are being depleted, with half-depletion predicted to occur between 2040 and 2060. Most of the P applied in fertilizers may be sorbed by soil, and not be available for plants lacking specific adaptations. On the severely P-impoverished soils of south-western Australia and the Cape region in South Africa, non-mycorrhizal species exhibit highly effective adaptations to acquire P. A wide range of these non-mycorrhizal species, belonging to two monocotyledonous and eight dicotyledonous families, produce root clusters. Non-mycorrhizal species with root clusters appear to be particularly effective at accessing P when its availability is extremely low.
There is a need to develop crops that are highly effective at acquiring inorganic P (Pi) from P-sorbing soils. Traits such as those found in non-mycorrhizal root-cluster-bearing species in Australia, South Africa and other P-impoverished environments are highly desirable for future crops. Root clusters combine a specialized structure with a specialized metabolism. Native species with such traits could be domesticated or crossed with existing crop species. An alternative approach would be to develop future crops with root clusters based on knowledge of the genes involved in development and functioning of root clusters.
Root clusters offer enormous potential for future research of both a fundamental and a strategic nature. New discoveries of the development and functioning of root clusters in both monocotyledonous and dicotyledonous families are essential to produce new crops with superior P-acquisition traits.
全球磷（P）储量正在枯竭，预计在2040年至2060年之间会出现一半的储量枯竭。施用于肥料中的大部分磷可能会被土壤吸附，而缺乏特定适应性的植物无法利用这些磷。在澳大利亚西南部和南非开普地区严重缺磷的土壤上，非菌根物种表现出高效获取磷的适应性。这些非菌根物种广泛分布于两个单子叶植物科和八个双子叶植物科，它们会产生根簇。当磷的有效性极低时，具有根簇的非菌根物种似乎在获取磷方面特别有效。
需要培育出能从吸磷土壤中高效获取无机磷（Pi）的作物。澳大利亚、南非和其他缺磷环境中具有根簇的非菌根物种所具备的性状，对于未来作物来说是非常理想的。根簇将一种特殊结构与特殊代谢结合在一起。具有此类性状的本地物种可以被驯化或与现有作物品种杂交。另一种方法是基于对参与根簇发育和功能的基因的了解，培育具有根簇的未来作物。
根簇为未来的基础研究和战略研究提供了巨大潜力。对单子叶植物科和双子叶植物科根簇发育和功能的新发现，对于培育具有优异磷获取性状的新作物至关重要。
