Control of infertility in wheat by phenotype screening and genetic analysis of varieties and breeding lines

小麦开花后产出的谷物可供人类、动物和工业使用。产量是花的数量和成功结粒的花的比例的乘积。英国的小麦产量普遍较高，但在某些环境条件下，一些品种表现出不育（开花结粒比例低）。这个问题的一个例子发生在20世纪80年代中期的冬小麦品种“Moulin”上，当时糟糕的粮食状况给种植者造成了高达90%的损失。小麦不育仍然是一个严重的威胁，因为具有这一弱点的品种可能会通过目前的试验系统，造成严重的产量失败。此外，较低和较不明显的不育水平可能会抑制小麦产量。据估计，生育率每下降1%，英国就会损失1800万英镑（即粮食价格为每吨120英镑，产量为1500万吨）。因此，消除导致不育的等位基因将提高产量并防止产量失败。尽管这个问题很严重，但人们对导致某些品种易患不孕症的基因知之甚少。为了解决这个问题，生产英国95%小麦品种的Nickerson-Advanta UK Ltd、RAGT Seeds Ltd和KWS UK Ltd与英国本土谷物管理局（HGCA）、苏格兰农业学院（SAC）和约翰英尼斯中心（JIC）合作启动了一个项目。这些公司将提供父母之间的双单倍体（DH）群体，已知他们对不孕症的易感性不同。这些种群将通过SAC在已知可诱导可再生不育水平的地点生长。通过结合基因数据，将有可能确定控制该性状的数量性状位点（QTL）。这将允许育种者对这些不良影响进行选择。将对五个不同的人群进行研究，主要目的是确定不孕不育是否有一种或几种遗传原因。这对于制定应对这一问题的战略非常重要。结果将在公司提供的更多品种和品系中进行测试，结果最终将纳入新的测试制度，这将有助于防止“有风险”的品系进入市场。

Flowering in wheat results in the production of grain that is harvested for human, animal and industrial use. Yield is a product of the number of flowers and the proportion of the flowers that successfully set grain. Wheat yields in the UK are generally high but some varieties show infertility (a low proportion of flowers setting grain) under certain environmental conditions. An example of this problem occurred in the winter wheat variety 'Moulin' in the mid 1980's when poor grain set caused losses to growers of up to 90%. Wheat infertility remains a serious threat because a variety with this weakness may slip through the current trialling system and give a serious yield failure. In addition, lower and less obvious levels of infertility may be suppressing wheat yields. Each 1% loss in fertility is estimated to cost £18m to the UK (i.e. 15mt production at a grain price of £120 per ton). Eliminating alleles that cause infertility will therefore enhance yield and protect against yield failure. Despite the seriousness of this problem very little is known about the genes that make some varieties vulnerable to infertility. To address this, Nickerson-Advanta UK Ltd, RAGT Seeds Ltd and KWS UK Ltd, who produce 95% of the current wheat varietes in the UK, have initiated a project in collaboration with the Home Grown Cereals Authority (HGCA), the Scottish Agricultural College (SAC) and the John Innes Centre (JIC). The companies will provide doubled haploid (DH) populations between parent known to differ in vulnerability to infertility. These popluations will be grown by SAC in sites known to induce reproducible levels of infertility. By combining this with genotying data it will be possible to identify quantitative trait loci (QTL) that control the trait. This will allow breeders to select against these undesirable effects. Five diverse populations will be studied, and a primary aim is to determine if there are one or several genetic causes of infertility. This is important for developing a strategy to combat this problem. Results will be tested in a larger collection of varieties and lines provided by the companies and results will ultimately feed through into new testing regimes that will help prevent 'at risk' lines from reaching the market place.