IMPROMALT: Improving winter malting barley quality and developing an understanding of the interactions of introgressions with genetic background

麦芽酿造商、啤酒酿造商和酿酒商担心大麦作物的长期可持续性。欧洲许多地区的季节性问题导致啤酒大麦供应受限，阿根廷的收成高于平均水平，这才刚刚得到缓解。在英国，干旱条件导致大麦作物质量下降，即蛋白质样本增加，特别是在英格兰东部，那里是英国麦芽大麦的主要产地。在预测的气候变化情景下，这样的干旱条件可能会变得更加频繁，对春季作物的影响将远远超过冬季作物，冬季作物可以通过更早的成熟来逃脱夏季干旱的最严重影响。虽然冬季大麦可能因此提供更稳定的供应，但在过去20年里，英国麦芽农购买的比例下降了25%以上。这一下降是由于与春季相比，冬季作物的质量水平下降，因此蒸馏器平均每吨麦芽可以多生产16升原酒。对于一个预计将使用2012年收获的60万吨大麦的行业来说，这在生产效率上是一个非常显著的差异。目前英国所有的冬季大麦麦芽品种都是从1965年首次推荐的Maris Otter衍生而来的。Maris Otter将老品种Proctor的春季麦芽质量属性与先锋的冬季习惯结合在一起。普罗科特多年来一直是英国主要的春季麦芽品种，但Triumph的引入在质量和产量方面都是春季作物的一次巨大飞跃。在之前的一个项目中，我们分析了英国春麦和冬麦麦芽品种的DNA指纹，以确定这两种作物之间与麦芽质量相关的遗传差异。虽然植物育种者之前曾试图将春季的质量属性引入冬小麦，但他们一直依靠偶然事件来组装正确的基因，当作物的基因差异达到数千个时，这是一项不可能完成的任务。但我们现在有知识和工具以高度有针对性的方式将春季属性导入冬麦，以检验这样的假设，即它们的引入将改善冬麦的麦芽品质。从这项建议中产生的种质将被该项目的植物育种伙伴用于进一步的杂交和选择，以培育出接近春季质量水平但具有适合当代耕作实践的合适农艺背景的改良冬季制麦品种，从而重新引起人们对使用冬季大麦酿造用于酿造和蒸馏的兴趣。如上一段所述，更多地使用冬季作物可能会在未来提供更稳定的啤酒大麦供应。由于各种市场因素导致麦芽供应变得更加紧张，转向产量更高的冬季作物也将意味着，对更有利可图的作物争夺土地的影响将对麦芽大麦供应产生不那么明显的影响。由于六行大麦品种的产量往往高于两行大麦，较长期的目标是开发六种行麦芽类型，以进一步减少确保啤酒大麦供应所需的土地面积。

Maltsters, brewers and distillers are concerned about the long-term sustainability of the barley crop. Seasonal problems in many parts of Europe resulted in a restricted malting barley supply that has only just been alleviated by an above average harvest in Argentina. Within the UK, drought conditions resulted in reduced barley crop quality, i.e. higher protein samples, particularly in Eastern England, where much English malting barley is sourced. Under predicted climate change scenarios, such drought conditions are likely to become more frequent and will affect the spring crop much more than the winter crop, which can escape the worst effects of summer drought through a much earlier maturity. Whilst winter barley might therefore provide a more consistent supply, the proportion bought by English maltsters has declined by over 25% over the past 20 years. This decline is due to the reduced quality level of the winter crop compared to the spring so that distillers can produce 16 more litres of raw spirit per tonne of malt on average from the latter. For an industry predicted to use 600,000t of barley from the 2012 harvest, this is a highly significant difference in production efficiency.All current UK winter barley malting varieties have been derived from Maris Otter, first recommended in 1965. Maris Otter combined the spring malting quality attributes of an older variety, Proctor, with the winter habit of Pioneer. Proctor was the major spring malting variety in the UK for many years but the introduction of Triumph was a quantum leap forward for the spring crop in terms of both quality and yield. In a previous project, we have analysed DNA fingerprints of UK spring and winter barley malting cultivars to identify genetic differences between the two crops that are associated with malting quality. Whilst plant breeders have previously tried to introgress spring quality attributes into winter barley, they have relied on chance events to assemble the right genes, which is an impossible task when the crops differ at thousands of genes. But we now have the knowledge and tools to conduct the introgression of spring attributes into winter barley in a highly targeted manner to test the hypothesis that their introduction will improve winter malting quality. The germplasm emerging from this proposal will then be used by the plant breeding partners of the project in further rounds of crossing and selection to develop improved winter malting quality cultivars that approached the spring quality levels but in a suitable agronomic background for contemporary farming practise and would thus re-generate interest in using winter barley for malting for use in brewing and distilling. As indicated in the previous paragraph, greater use of the winter crop is likely to provide a more consistent supply of malting barley in the future. As malting supplies are becoming tighter due to a variety of market factors, a switch to the higher yielding winter crop would also mean that the effects of competition for land for more profitable crops would have a less pronounced effect upon malting barley supply. As six row barley varieties tend to have a higher yield than two row, a longer term aim is to develop six row malting types that would further decrease the land area required to secure a malting barley supply.