Raising the ceiling on UK wheat yields / introgression and assessment of novel 'large-ear' CIMMYT germplasm into UK pre-breeding lines

英国小麦的大多数主要变化，如引入矮秆基因（降低了植株高度，但增加了产量），都是从远缘杂交中引入的。远缘杂交仍然可以用来引入新的基因，从而使英国小麦发生进一步的重大变化。这里提出的建议将引入新的基因，赋予更长的穗轴（=穗轴），与墨西哥小麦（来自CIMMYT）的穗育性提高相关，这可能有助于英国小麦总产量的飞跃。测试这一点的材料已经生产出来了。具体来说，我们已经从墨西哥“大耳朵”线和生产力（高效地将阳光转化为糖）英国适应小麦Rialto之间的杂交中创建了一个品系群体。在一项初步研究中，我们已经表明，穗轴长度与穗育性（和单位土地面积的籽粒数）呈正相关。这项提案要求资金来研究为什么墨西哥小麦每穗产量比英国小麦多，以及我们是否可以使用相同的基因来提高英国小麦产量。该计划与来自CPB-Twyford Ltd的英国植物育种家合作，从墨西哥材料中生产含有这些新基因的小麦预育种系。对于育种者来说，要将新的性状引入英国的优良品种，他们必须首先知道哪些基因负责控制这些性状，以及它们如何导致品种之间的差异。因此，我们将绘制控制穗育性的基因，并在此过程中开发遗传标记，以便于在育种计划中进行选择。不同国家的天气和环境条件可能有很大差异，在某些国家有用的基因可能在其他国家没有。我们计划进行生理实验，以确定为什么墨西哥小麦每穗有更多的谷粒，以及这如何有助于提高英国小麦品种的产量。我们还将进行实验，以检查这些基因是否影响作物水平上产量的其他重要决定因素，如穗数和粒重。最重要的是，由于Rialto的高光合能力与“大穗”系中更肥沃的穗相结合，应该会有额外的好处。我们已经有了完成这项工作所需的杂交种子，但需要资金来了解小麦如何控制每穗产量。我们的工业合作伙伴将利用他们的育种专业知识来制造适合英国育种的新品系，我们将帮助开发这些品系，并利用这些品系来帮助我们了解每穗产生多少谷物的遗传学。使用这种结合的方法，我们将确定一个候选基因池，可能直接影响这一性状。

Most major changes in UK wheats, such as the introduction of dwarfing genes (which reduced plant height, but increased the yield) have been introduced from wide crosses. Wide crosses can still be used to introduce new genes which allow further major changes to be made in UK wheats. The proposal presented here will introduce new genes conferring longer ear rachis (= axis of the ear) associated with improved ear fertility from Mexican wheats (from CIMMYT) which could facilitate a quantum leap in overall yield in UK wheats. The material to test this has already been produced. Specifically, we have created a population of lines from a cross between the Mexican 'big-ear' line and a productive (highly efficient at turning sunlight into sugar) UK adapted wheat, Rialto. In a preliminary study, we have shown rachis length to be positively correlated with ear fertility (and grain number per unit land area). This proposal asks for funds to look at why the Mexican wheat produces more grain for each ear than UK wheat and whether we can use the same genes to improve UK wheat yields. The programme works with UK plant breeders from CPB-Twyford Ltd to produce wheat pre-breeding lines containing these new genes from the Mexican material. For breeders to introduce novel traits into elite UK varieties, they must first know which genes are responsible for controlling the traits and how they work to cause differences between varieties. So, we will map the genes controlling ear fertility and in doing so develop genetic markers to facilitate their selection in breeding programmes. The weather and environmental conditions can vary considerably between different countries and genes that may be useful in some countries may not be in others. We plan to carry out physiological experiments which would identify why the Mexican wheat has more grains in each ear and how this might help improve wheat yield in the UK varieties. We will also carry out experiments to examine whether these genes influence other important determinants of yield at the crop level, such as ear number and grain weight. Crucially, there should be added benefits due to the high photosynthetic ability of Rialto combined with more fertile ears in the 'big-ear' line. We already have seed from the crosses which are needed to do this work, but need funding to understand how wheat controls the number of grains produced per ear. Our industrial partner will use their breeding expertise to make new lines suited to UK breeding, and we will help develop these lines and also use these lines to help us understand the genetics of how many grains are produced per ear. Using this combined approach we will then identify a pool of candidate genes which may directly influence this trait.