Raising yield potential in wheat
Raising yield potential in wheat
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DOI：
10.1093/jxb/erp016
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发表时间：
2009-05-01
影响因子：
6.9
通讯作者：
Angus, William J.
中科院分区：
文献类型：
--
作者：
Reynolds, Matthew;Foulkes, M. John;Angus, William J.
作物研究的最新进展有可能加速小麦的遗传增益，特别是如果与育种观点相协调。例如，通过利用Rubisco催化速率的自然变化或采用C-4代谢来改善光合作用，可以将产量潜力的基线提高50%或更多。然而，穗的肥力也必须提高，以允许充分利用整个作物生命周期的光合能力，这有几个组成部分。虽然更大的辐射利用效率将增加总同化物穗生长，从而增加潜在的粒数，优化的物候模式将允许最大限度地分配可用的同化物的穗。未充分利用的光合能力在灌浆过程中的精英材料的证据表明不必要的小花败育。因此，更好地了解其生理和遗传基础，包括响应光周期或生长限制资源的可能信号，可能会使小花败育最小化，以实现更优化的源库平衡。然而，为了防止因倒伏而造成的产量损失，可能需要在穗生长期间将同化物分配到竞争性汇方面进行权衡，以改善根的锚定和茎的强度。可用于补充常规方法的育种技术包括与小麦族成员广泛杂交以拓宽小麦基因库，以及生理和分子育种策略性地联合收割机互补性状并更有效地鉴定优良后代。
Recent advances in crop research have the potential to accelerate genetic gains in wheat, especially if co-ordinated with a breeding perspective. For example, improving photosynthesis by exploiting natural variation in Rubisco's catalytic rate or adopting C-4 metabolism could raise the baseline for yield potential by 50% or more. However, spike fertility must also be improved to permit full utilization of photosynthetic capacity throughout the crop life cycle and this has several components. While larger radiation use efficiency will increase the total assimilates available for spike growth, thereby increasing the potential for grain number, an optimized phenological pattern will permit the maximum partitioning of the available assimilates to the spikes. Evidence for underutilized photosynthetic capacity during grain filling in elite material suggests unnecessary floret abortion. Therefore, a better understanding of its physiological and genetic basis, including possible signalling in response to photoperiod or growth-limiting resources, may permit floret abortion to be minimized for a more optimal source:sink balance. However, trade-offs in terms of the partitioning of assimilates to competing sinks during spike growth, to improve root anchorage and stem strength, may be necessary to prevent yield losses as a result of lodging. Breeding technologies that can be used to complement conventional approaches include wide crossing with members of the Triticeae tribe to broaden the wheat genepool, and physiological and molecular breeding strategically to combine complementary traits and to identify elite progeny more efficiently.