Toxicity of Epichloë endophytes in agricultural grass species on pastures

本项目的主要目的是了解表生真菌在德国牧场冷季型牧草和商业种子混合物中的分布和毒性。在第一个工作包中，将对德国各地150个播种牧场(50头牛、50头羊和50匹马)的表观物种以及途径生物碱和最终产品的基因和化学多样性进行量化。此外，还将对50个放牧绵羊的半天然草原和50个马匹患有严重板层炎病例的种马牧场进行测试。还将对200个牧场使用的种子混合物进行分析，以找出受Eichloë感染的寄主草和有毒化合物的可能来源。在第二个工作包中，我们将从欧洲和国际市场购买可用于牧场和草坪的商业种子混合物，以再次寻找表观内生植物及其生物碱的存在。当种子混合物中应该含有受环氧氯丙烷感染的种子时，我们将在大学花园中播种这种混合物，并检测一年生植物中的生物碱，以评估它们的毒性。最后，我们将要求欧洲的主要种子生产商和德国的联邦植物变种办公室获得受感染的混合种子的牧草品种，以检测表观感染的来源。通过这个项目，我想为即将到来的关于共生修饰有机体的社会辩论增加科学数据。因此，目前尚不清楚牧草种子育种者是否以及在何种程度上故意使用这些新技术，以及在牧场播种牧草是否会损害牲畜。通过这项研究，我的目标是解决以下关键研究问题：(1)马、牛和羊的种子牧场中表观内生真菌的出现和生物碱浓度是否不同？(2)与饲养牲畜的半自然草地相比，播种牧场的表观内生植物是否不同？(3)马的舌炎与表观内生真菌的出现和放牧草地中的生物碱浓度有关吗？(4)欧洲哪些混合草种感染了表观内生真菌，它们对牲畜有毒性吗？它们能保护宿主草免受昆虫草生植物的侵染吗？(5)欧洲哪些草种感染了表观内生真菌？

The main objective of this project is to understand the distribution and toxicity of systemic endophytic fungi of the genus Epichloë in cool season grass species in German pastures and in commercially available seed mixtures. In a first work package, Epichloë species as well as genotypic and chemical diversity of pathway alkaloids and endproducts will be quantified from 150 seeded pastures (50 cattle, 50 sheep and 50 horse pastures) across Germany. In addition, 50 semi-natural grasslands with grazing sheep and 50 seeded horse pastures with severe cases of the disease laminitis in horses will be tested. Seed mixtures used for the 200 pastures will be also analyzed, to find the possible sources of Epichloë infected host grass and toxic compounds. In a second work package, we will purchase commercially available seed mixtures for pastures and lawns from the European and international market to search again for the occurrence of Epichloë endophytes and their alkaloids. When seed mixtures should contain Epichloë infected seeds, we will sow out the mixture in the University garden and detect alkaloids in one-year-old plants, to estimate their toxicity. We finally will ask the main seed producers in Europe and the Federal Office of Plant Varieties in Germany to get grass cultivars of infected seed mixtures, to detect the source of Epichloë infections. With this project, I want to add scientific data to an upcoming debate in society about symbiotically modified organisms. Thereby it is unknown if and to which extend seed breeders of grass deliberately use these new technologies and if seeded grass on pastures could harm livestock. With this study, I aim to address the following key research questions:(1) Are the occurrence of Epichloë endophytes and the alkaloid concentrations in grass different in seeded pastures of horses, cattle and sheep? (2) Have seeded pastures different Epichloë endophytes compared to semi-natural grasslands with livestock? (3) Is laminitis in horses related to Epichloë endophyte occurrence and alkaloid concentrations in the grazed grass? (4) Which grass seed mixtures in Europe are infected with Epichloë endophytes, and are the mixtures toxic for livestock and can they protect the host grass from insect herbivory? (5) Which European grass cultivars are infected with Epichloë endophytes?