Developing integrated approaches for pest and disease control in horticultural field crops (IAPAD)

芜菁黄化病毒(Turnip YellowsVirus，TuYV)是一种重要的蔬菜甘蓝病原菌(拉丁名：甘蓝、花椰菜等)。和油菜(OSR)在英国和欧洲。许多抽样的农作物都有非常高水平的图伊夫病毒感染。与许多病毒不同，TuYV在大多数甘蓝中不会引起非常明显的症状(引起圆白菜尖烧的地方是个例外)。这意味着许多种植者没有意识到感染。尽管没有明显的症状，但我们发现TuYV使卷心菜减产高达36%，球芽甘蓝减产高达65%。据估计，仅在英国，OSR产量就下降了高达30%(每年损失6700万至1.8亿英镑)。土豆病毒可以在蔬菜甘蓝、油菜和杂草之间传播，导致作物高度侵染。一种非常常见的绿蝇(桃属土豆蚜虫)传播土豆病毒；一旦感染病毒，它们就会终身传播。在温室试验中，我们确定了控制TuYV的最佳杀虫剂种子处理和喷雾。田间试验还表明，不同的甘蓝和甘蓝品种对TuYV有不同的感病能力(都是感病的，但有些不是很敏感)，而且感染的越早，产量损失就越大。我们还发现了一些甘蓝对TuYV的极端抗性来源，并通过测定许多分离物的遗传密码来研究TuYV的多样性。该项目的合作者在英国各地有一个吸引器网络，用来诱捕飞行中的绿蝇。他们识别不同的绿蝇物种，包括桃属土豆蚜虫，并对它们进行计数。他们还在开发一种分子技术来检测绿叶病毒中的TuYV。所有这些发现都提供了将它们结合到一个综合计划中的机会，从而对TuYV进行最佳控制。为了开发这一综合控制计划，我们打算在英国的两个地区进行田间试验。在一个地点，我们将引入携带TuYV的绿蝇，以提供高感染压力，而在另一个地点，我们将依靠自然感染。在这些试验中，我们将分别、成对和成对地应用单个成分(部分植株抗性、最好的种子处理和最好的喷雾)，以量化单独处理和联合处理的效果。这将确定最佳组合并量化不同处理之间的协同作用。喷雾处理的时间将通过桃子-土豆蚜虫飞翔的时间来确定，这将从试验周围的吸力捕捉器和水捕获器得知。为了建立和改进综合计划，我们将在我们的抗病甘蓝品系中确定对TuYV极端抗性的最佳来源。这将与一条易受影响的线交叉。后代将通过向植物感染TuYV进行抗性/敏感性测试，并使用一种名为ELISA的定量测试来测试TuYV。下一代植物中的一些将对TuYV敏感，一些将具有抗性。通过分析这些植物的基因/染色体/RNA/DNA，并将其与植物的感病/抗病状态进行比较，这将使分子标记的开发成为可能。种子公司将利用这些来显著加快将抗性基因整合到商业上可接受的品种中。我们正在与先正达和陶氏化学合作，优化种子处理和喷雾，并与种子公司Tozer、Sakata UK、Enza Zden和Rijk Zwaan UK合作开发TuYV抗性。我们还与大葱和Brassica农业公司合作，他们与农民合作。通过这些合作，种植者将利用研究成果(TuYV综合控制方案和TuYV的新抗性来源)，以减少蔬菜和投入物中的残留，提高产量，从而促进粮食安全。

Turnip yellows virus (TuYV) is a very important pathogen of vegetable brassicas (Latin name Brassica oleracea; cabbage, cauliflower, Brussels sprout, broccoli etc.) and oilseed rape (OSR) in the UK & Europe. Many crops sampled have had very high levels of TuYV infection. Unlike many viruses, TuYV does not cause very obvious symptoms in most brassicas (storage cabbage where it causes tipburn is the exception). This has meant many growers are unaware of the infections. Despite lack of obvious symptoms we showed that TuYV reduces the yield of cabbage by upto 36% and Brussels sprouts by upto 65%. Estimates of OSR yield reductions in the UK alone are upto 30% (losses of GBP 67-180 million/annum). TuYV can move between vegetable brassicas, oilseed rape and weeds, resulting in the high levels of infection of crops seen.A very common greenfly (peach-potato aphid) transmits TuYV; once they acquire the virus they transmit for life. In glasshouse experiments we have identified the best insecticide seed treatments and sprays for controlling TuYV. We have also shown in the field that different cabbage and Brussels sprout cultivars have different susceptibilities to TuYV (all are susceptible, but some less so than others) and that the earlier plants are infected, the greater the yield loss. We have also found a number of sources of extreme resistance to TuYV in Brassica oleracea and have been studying the diversity of TuYV by determining the genetic code of many isolates. Collaborators in the project have a network of suction traps around the UK that trap flying greenfly. They identify the different greenfly species including the peach potato aphid and count them. They are also developing a molecular technique to detect TuYV in the greenfly.All these discoveries provide the opportunity to combine them in to an integrated programme that will give optimal control of TuYV. To develop this integrated control programme we intend to do field experiments in two regions of the UK. At one location we will introduce greenfly carrying TuYV to provide high infection pressure and at the other location we will rely on natural infection. In these experiments we will apply the individual components (partial plant resistance, the best seed treatment and the best sprays) separately, in pairs and in threes in order to quantify the efficacy of individual and combined treatments. This will identify the best combinations and quantify synergy between treatments.The timing of spray treatments will be informed by when peach-potato aphids are flying, this will be known from the suction trap and water trap catches around the experiment.To build on and improve the integrated programme we will identify the best source of extreme resistance to TuYV in our resistant B. oleracea lines. This will be crossed with a susceptible line. The offspring will be tested for resistance/susceptibility by challenging plants with TuYV and testing for TuYV using a quantitative test called ELISA. Some of the next generation of plants will be susceptible to TuYV and some will be resistant. By analysing the genes/chromosomes/RNA/DNA of these plants and comparing this with the susceptibility/resistance status of the plants, it will allow the development of molecular markers. Seed companies will use these to significantly speed up the incorporation of the resistance genes into commercially acceptable varieties. We are collaborating with Syngenta and Dow in the optimal use of seed treatments and sprays and with the seed companies Tozer, Sakata UK, Enza Zaden and Rijk Zwaan UK on the TuYV resistance exploitation. We are also working with Allium and Brassica Agronomy who work with farmers. Through these collaborations the outcomes of the research (integrated programme for TuYV control and new sources of resistance to TuYV) will be exploited by growers in order to reduce residues in vegetables and inputs and increase yields, thereby contributing to food security.