Host plant relationships of insect potential vectors of Xylella fastidiosa

松材线虫是一种破坏性最强的植物病害，在橄榄、葡萄、樱桃、迷迭香和薰衣草等主要农作物、观赏植物和林木上造成了严重的产量损失和死亡。虽然在英国尚未有记录，但由于从该疾病流行地区大量进口这些植物，该菌对园艺造成了严重威胁。粉锈菌是一种木质部受限的细菌，由木质部取食的昆虫传播，特别是青蛙和某些较大的叶蝉。常见且分布广泛的‘草地唾虫’，被认为是欧洲的主要媒介；它也是已知的多食性昆虫之一，寄主植物超过500种。学生将学习以薰衣草和葡萄为食的Spumarius的基本生态学、行为和生理学，结合实地调查、实验室和半野外选择实验以及对媒介取食行为和生理的实验室检查。我们来自Downderry Nursery的2019年初步数据表明，Spumarius在某些薰衣草物种和品种之间进行了差异选择；可能预计葡萄品种之间会有类似的偏好，但到目前为止还没有进行过调查。学生将回答以下问题：海绵对不同的薰衣草物种/品种和葡萄品种表现出什么偏好？这如何影响昆虫的表现和适合度？海绵的取食行为和生理因植物基因而异，这与性能有关吗？上述行为和生理的差异可能会影响木霉的传播吗？对海绵和其他以木质部为食的昆虫的了解加深，将提高英国应对未来任何木霉入侵的能力。它还将为贸易政策提供信息，说明哪些植物物种/品种应受到更严格的进口管制。

Xylella fastidiosa is regarded as one of the most devastating plant diseases, causing high yield losses and death in major crops, ornamentals and forest trees, including olive, grapevine, cherry, rosemary and lavender.Although not yet recorded in the UK, Xylella is a serious threat to horticulture due to the high volume of imports of these plants from areas where the disease is prevalent. X. fastidiosa is a xylem-limited bacterium that is transmitted by xylem-feeding bugs, notably froghoppers (spittlebugs) and certain larger leafhoppers. The common and widespread 'Meadow spittlebug', Philaenus spumarius, is considered to be the primary vector in Europe; it is also one of the most polyphagous insects known, with a host plant list in excess of 500 species.The student will study the fundamental ecology, behaviour and physiology of P. spumarius feeding on lavender and grapevine (both high-risk hosts for UK incursion), combining field surveys, laboratory and semi-field choice experiments and laboratory examination of vector feeding behaviour and physiology. Our preliminary 2019 data from Downderry Nursery indicates that P. spumarius differentially selects between certain lavender species and varieties; similar preferences might be expected between grapevine cultivars but hitherto have not been investigated. The student will address the following questions:What preferences does spumarius show for different lavender species/varieties and grapevine cultivars?How does this affect insect performance and fitness?How does spumarius feeding behaviour and physiology differ according to plant genotype and is this related to performance?Are the above differences in behaviour and physiology likely to affect Xylella transmission?Improved understanding of feeding in P. spumarius and other xylem-feeding insects will enhance UK capacity to respond to any future incursion of Xylella. It will also inform trade policy in terms of which plant species/varieties should be subject to greater import controls.