Novel strategies for genetic improvement of disease resistance in perennial ryegrass

多年生黑麦草（PRG）为英国的牲畜提供了大部分饲料，并通过种子销售为萌芽控股（GHL）提供商业回报。anderchslera andersonii或网斑病是PRG的一种严重真菌疾病，英国处于高或中等风险。第一次刈割时，每公顷生物量产量下降可超过1dm。现有品种抗性好，英国高糖草（HSG）品种抗性差。使用杀菌剂不是一个可行的选择。减少HSG品种的使用将导致销售减少，增加抗性更高但糖含量不高的进口品种，从而提高反刍动物的营养效率，减少温室气体排放。例如，HSG种子销售减少20%将对GHL产生严重的商业影响。阿伯里斯特威斯大学IBERS将与GHL合作，利用基因组选择辅助的新回交策略，培育抗净斑病的HSG品种。这将提高抗病杂交种恢复先前农艺和HSG性状值的速度和可靠性，从而帮助GHL保持或增加市场份额。

Perennial ryegrass (PRG) provides the majority of forage for livestock in the UK, and delivers commercial returns to Germinal Holdings (GHL) through seed sales. Drechslera andersonii or net blotch is a serious fungal disease of PRG, and the UK is at high or medium risk. Biomass yield decreases can be more than 1t DM per hectare in the first cut. Few current varieties have good resistance, and the UK bred high sugar grass (HSG) varieties show poor resistance. Fungicide use is not a viable option. Reduction in the use of HSG varieties will lead to decreasing sales and increased imported varieties with higher resistance, but without the high sugar content, which improves ruminant nutrition efficiency and reduce GHG emissions from them. A 20% reduction in HSG seed sales for example would have serious commercial implications for GHL. IBERS, Aberystwyth University will collaborate with GHL to breed net blotch resistant HSG varieties using a novel backcross strategy aided by genomic selection. This will increase the speed and reliability with which disease resistant hybrids recover previous values of agronomic and HSG traits, and thus help GHL maintain or increase market share.