Arable - Understanding phenotypic and genetic variation in wing polyphenism in an aphid virus vector

蚜虫是世界上最重要的经济害虫之一，每年给各种粮食作物和商品作物造成数十亿美元的产量损失。蚜虫之所以具有如此破坏性，部分原因是它们是多种植物病毒的高效媒介。蚜虫表现出的一个显著特征，对它们在农作物中传播病毒的能力具有重大影响，那就是它们能够对环境提示做出完全不同的有翼和无翅形式的反应。这种发育可塑性被称为翅多物性，并允许蚜虫产生后代，这些后代优化为最大限度地繁殖输出(无翼形式)或能够通过飞行(有翼形式)分散以响应环境条件。我们最近发现了显着的变异，在多大程度上，在拥挤(通常会导致翅的产生)和非拥挤的条件(通常会导致无翅的产生)下，具有破坏性的桃蚜的不同无性系都会产生有翅的形式。这一发现之所以重要，有两个原因。首先，蚜虫基因产生有翅形式的程度将直接影响其在作物中和作物之间传播植物病毒的能力。其次，鉴定不同无性系的蚜翅产量变异为鉴定支持这种变异的基因和遗传变异提供了机会。尽管这一初步数据很重要，但不同种群间的翅多表型变异程度及其遗传基础尚不清楚。这个项目的目的是通过开发最近为这种害虫开发的独特的生物学和基因组资源来解决这一知识差距，该资源包括一个由110个完全测序的不同遗传无性系组成的活文库。在该项目的第一个目标中，我们将在拥挤和非拥挤的条件下对活库中的每个桃蚜克隆进行表型以进行翅多表型。所获得的数据将提供前所未有的洞察力，了解从每个种植作物的大陆收集的烟粉虱翅多物性的表型变异程度。了解这一关键性状的变异程度将使我们在未来能够更准确地预测病毒在作物中的传播。此外，为每个无性系产生稳健的表型信息，将使我们能够在目标2中研究其基础遗传基础。为此，我们将利用克隆文库中每个烟粉虱基因的现有序列数据，以一种以前从未可能实现的方式识别与翅多表型变异相关的基因和遗传变异。所获得的数据将提供对这种适应性特征的分子基础的基本见解，并是开发针对参与翅膀生产的关键基因或其产物以减少病毒传播的新干预措施的第一步。

Aphids are among the world's most economically important group of insect pests, causing billions of US dollars of yield loss per annum to a wide range of food and commodity crops. Aphids are, in part, so damaging because they are highly efficient vectors of numerous plant viruses. A remarkable trait exhibited by aphids, that has a major impact on their ability to transmit viruses in crops, is their ability to produce completely different winged and non-winged forms in response to environmental cues. This developmental plasticity is termed wing polyphenism and allows aphids to produce offspring that are optimised for maximum reproductive output (non-winged form) or capable of dispersing via flight (winged forms) in response to environmental conditions. We recently uncovered marked variation in the extent to which genetically distinct clones of the damaging aphid pest, Myzus persicae, produce winged forms under both crowded (which typically induces wing production) and non-crowded conditions (which typically results in the production of non-winged forms). This finding is important for two reasons. Firstly, the extent to which an aphid genotype produces winged forms will directly impact its capacity to disperse plant viruses through and between crops. Secondly, the identification of variation in aphid wing production in different aphid clones provides an opportunity to identify the genes and genetic variation underpinning this variation.Despite the importance of this preliminary data, the extent of phenotypic variation in wing polyphenism across diverse populations of M. persicae, and its underpinning genetic basis, remains unknown. The aim of this project is to address this knowledge gap by exploiting a unique biological and genomic resource recently developed for this aphid pest comprising a living library of 110 fully sequenced genetically distinct clones of M. persicae.In the first objective of the project, we will phenotype each individual M. persicae clone in the living library for wing polyphenism under crowded and uncrowded conditions. The data obtained will provide unprecedented insight into the extent of phenotypic variation in wing polyphenism in M. persicae collected from every continent where crops are grown. Understanding the extent of variation in this key trait will allow us, in future, to much more accurately predict virus transmission in crops. Furthermore, generating robust phenotypic information on wing polyphenism for each clone will allow us to investigate its underpinning genetic basis in Objective 2. For this we will leverage our existing sequence data for each M. persicae genotype in the clone library to identify genes and genetic variation associated with phenotypic variation in wing polyphenism in a way that has never been previously possible. The data obtained will provide fundamental insight into the molecular basis of this adaptive trait, and is a first step in the development of novel interventions that target key genes, or their products, involved in wing production in order to reduce virus transmission.