Protecting second wheat through the reduction of take-all inoculum build up

全蚀病是英国冬小麦最重要的真菌病之一，有多达一半的作物受到影响，农民每年损失高达6000万英镑。该病害造成根系损害，导致水分和氮吸收减少，从而影响产量和品质。目前的控制措施并非100%有效，包括文化做法和化学控制。洛桑研究所之前的研究表明，阿瓦隆和卡丹扎两种作物在收获后留在土壤中的“万能菌”数量上存在差异。这就影响了第二茬小麦的接种量。控制这一性状的遗传位点已经确定，该项目的目的是利用这些结果开发抗全蚀性积累（TAB）的品种。第一个目标将是评估来自三个合作伙伴的英国品种和品系的进一步范围，以考虑这种全面积累表型。第二个目标将是利用Avalon x Cadenza WGIN定位群体中的更多品系，进一步绘制遗传位点。从这一分析，我们的目标是更精细地绘制这一性状，以便为我们提供用于标记辅助选择（MAS）的诊断标记。第三个目标是探索是否存在一种地上可见的作物生理性状，该性状与地下土壤中积累的低或高全蚀菌量有关。这种目视评价可以在将来被育种者用作额外的诊断标记。在这个项目中，我们将选择品种和先进的材料直接在市场上使用，这些品种和材料显示出这种减少的TAB表型，为目前进入注册的材料提供附加值。开发具有这种独特性状的英国品种不仅有利于我们的公司，而且有利于小麦产量，特别是通过提高第二季小麦的产量，英国小麦总产量将持续提高190万吨。

Take-all is one of the most important fungal diseases of UK winter wheat, with up to half the crop being affected with losses costing farmers up to 60m per annum. The disease causes root system damage, resulting in reduced water and nitrogen uptake, which impacts on both yield and quality. Current control measures are not 100% effective and include cultural practices and chemical control. Previous work at Rothamsted Research has shown that the varieties Avalon and Cadenza show differences in the amount of the take-all fungus left behind in the soil after harvest. This influences the inoculum available for infection of a second wheat crop. The genetic loci controlling this trait have been identified and the aim of this project is to utilise these results in developing varieties which resist take-all build up (TAB). The 1st objective will be to assess a further range of UK varieties and lines from the three partners with respect to this take-all build-up phenotype. The 2nd objective will be to map the genetic loci further, using more lines from the Avalon x Cadenza WGIN mapping population. From this analysis we aim to map this trait more finely in order to give us diagnostic markers for use in marker-assisted selection (MAS). The 3rd objective is to explore whether an above ground visible crop physiology trait exists which is associated with either low or high take-all inoculum build up in the soil below. This visual assessment could in the future be used as an additional diagnostic marker by the breeders.During this project, we will have selected varieties and advanced material for direct use in the market place which show this reduced TAB phenotype, giving added value to material currently entering registration. Development of UK varieties carrying this unique trait will benefit not only our companies, but also wheat productivity by increasing overall UK wheat yields consistently by up to 1.9 m tonnes pa specifically by improving the performance of 2nd wheat crops.