Novel strategies for genetic improvement of disease resistance in perennial ryegrass

多年生黑麦草抗病性遗传改良的新策略

• 批准号: BB/M028267/1
• 负责人: Leif Skot
• 金额: $ 30.26万
• 依托单位: Aberystwyth University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2015
• 资助国家: 英国
• 起止时间: 2015 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FM028267%2F1
• 关键词: Novel; strategies; genetic; improvement; disease

Perennial ryegrass (PRG) provides the majority of forage for livestock in the UK. Drechslera andersonii or net blotch is a serious fungal disease of PRG, and the UK is at high or medium risk. Yield effects can be over 1t DM per hectare in the first cut (British Society of Plant Breeders - Recommended List). Few current diploid 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 increase in imported varieties with higher resistance, but without the high sugar content, which improves ruminant nutrition efficiency. The project brings together the only UK owned forage grass and legume seed production and wholesale company (Germinal Holdings Ltd), and the major forage plant breeding and genetics research organisation within the UK (IBERS, Aberystwyth University) in a consortium that has the skills and commercial experience to deliver new net blotch resistant PRG varieties with HSG characteristics. IBERS, Aberystwyth University will breed net blotch resistant HSG varieties using a novel backcross strategy aided by genomic selection. This will increase the speed with which disease resistant hybrids recover previous values of agronomic and HSG traits. This has not been done before in a ryegrass breeding programme. New net blotch resistant HSG ryegrass varieties will help GHL maintain and increase market share in the UK and abroad. We have identified ecotypes with high net blotch resistance. They will initially be crossed with AberWolf, a high performing HSG varieties with low net blotch resistance. The F1 progeny will be assessed phenotypically for disease resistance, and genotyped with a 4000 molecular marker SNP chip. This allows us to identify quantitative trait loci (QTLs) for net blotch resistance. Secondly, prediction models have been developed to derive genomic estimated breeding values for agronomic and forage quality traits. This will enable us to select the best candidates for disease resistance as well as HSG traits. A polycross of the F1 plants will be performed to guarantee segregation of the disease resistance traits. By year 5 three further rounds of backcrossing with the recurrent HSG parent will have been completed. Seed will be set aside from year 3 for small scale field trials in Devon for the remaining two years. These field trials will also include a wide range of susceptible and resistant material with high or low water soluble carbohydrate (WSC) content for comparison and as controls. These rigorous trials will ensure that by the end of the project, we will have populations with much higher net blotch resistance in addition to the beneficial properties of AberHSG varieties in terms of yield, WSC and digestibility. A range of activities will be undertaken to publicise this work, and thus facilitate fast on-farm uptake of these new varieties. This includes communication with seed distributors, advisors and farmers. The technology will be demonstrated at various livestock shows, including demonstration plots, where possible. GHL will also produce easy to follow management guidelines for farmers.

多年生黑麦草（PRG）为英国的牲畜提供了大部分饲料。Drechslera 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。第一次收割时，产量影响可超过每公顷1吨DM（英国植物育种家协会-推荐清单）。目前很少有二倍体品种具有良好的抗性，英国育成的高糖草（HSG）品种表现出较差的抗性。使用杀真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，并增加进口品种，这些品种具有较高的抗性，但不具有高糖含量，这提高了反刍动物的营养效率。该项目汇集了英国唯一拥有的牧草和豆类种子生产和批发公司（German Holdings Ltd），以及英国主要的饲料植物育种和遗传学研究机构（IBERS，阿伯里斯特威斯大学），组成一个具有技术和商业经验的财团，提供具有HSG特性的新的抗网斑病PRG品种。IBERS，阿伯里斯特威斯大学将使用基因组选择辅助的新型回交策略培育抗网斑病HSG品种。这将增加抗病杂交种恢复先前农艺和HSG性状值的速度。这在以前的黑麦草育种计划中还没有做过。新的抗网斑病HSG黑麦草品种将有助于GHL保持和增加在英国和国外的市场份额。我们已经确定了具有高抗网斑病的生态型。它们最初将与AberWolf杂交，AberWolf是一种具有低净斑点抗性的高性能HSG品种。将对F1后代进行抗病性表型评估，并用4000分子标记SNP芯片进行基因分型。这使我们能够确定净斑病抗性的数量性状位点（QTL）。其次，已经开发了预测模型，以获得农艺和饲料品质性状的基因组估计育种值。这将使我们能够选择抗病性和HSG性状的最佳候选者。将进行F1植物的多交以保证抗病性状的分离。到第5年，将完成与复发HSG亲本的另外三轮回交。从第3年开始，将留出种子，在剩下的两年里在德文郡进行小规模田间试验。这些田间试验还将包括一系列具有高或低水溶性碳水化合物（WSC）含量的敏感和抗性材料，用于比较和作为对照。这些严格的试验将确保到项目结束时，我们将拥有具有更高净斑点抗性的种群，以及AberHSG品种在产量，WSC和消化率方面的有益特性。将开展一系列活动来宣传这项工作，从而促进这些新品种在农场的快速吸收。这包括与种子经销商、顾问和农民的沟通。该技术将在各种牲畜展览会上展示，包括在可能的情况下展示示范区。GHL还将为农民提供易于遵循的管理指南。

项目成果

Prediction of breeding values and variance in Lolium perenne (L.) breeding populations

黑麦草 (Lolium perenne (L.)) 育种群体育种值和方差的预测

• 发表时间: 2018
• 作者: Skot, L.

Implementation of Genomic Prediction in Lolium perenne (L.) Breeding Populations.

• DOI: 10.3389/fpls.2016.00133
• 发表时间: 2016
• 期刊: Frontiers in plant science
• 影响因子: 5.6
• 作者: Grinberg NF;Lovatt A;Hegarty M;Lovatt A;Skøt KP;Kelly R;Blackmore T;Thorogood D;King RD;Armstead I;Powell W;Skøt L
• 通讯作者: Skøt L

Encyclopedia of Applied Plant Sciences

应用植物科学百科全书

• DOI: 10.1016/b978-0-12-394807-6.00228-8
• 发表时间: 2017
• 作者: Skøt L