The Genetic Basis of Disease Resistance in Natural Populations of Silene alba

9615317 Antonovics植物受到多种病原体的侵害，这是农业中的一个严重问题。然而，病原体在决定野生物种丰度方面的作用却知之甚少；流行病似乎很少，病原体不太明显，对植物丰度的影响并不总是不言而喻的。在过去的十年里，Antonovics博士和他的同事们使用植物白色campion （Silene alba）的花药-黑穗病作为模型系统来了解病原体如何影响自然种群。个别植物对这种疾病的易感性不同，但这种易感性的遗传基础尚不清楚。目前也不清楚为什么种群没有完全产生抗药性；据推测，决定耐药性的基因有负面的副作用。本研究将探讨一个或多个基因是否参与易感性，利用DNA标记对这些基因进行定位，并研究抗性成本的原因。Antonovics博士还将研究这种耐药性是对许多病原体的普遍抗性还是只针对这一种真菌。鉴定抗性基因将使人们能够严格研究这些基因在自然界中的分布，以及它们在拯救植物种群免受疾病侵害方面所起的作用。这项研究将提高对病原体如何控制植物种群的理解，因此将与生物杂草控制和保护生物学直接相关。它还将为利用这些抗性基因开发具有抗性的转基因作物打开大门。

9615317 Antonovics Plants are assailed by a wide array of pathogens, and these are a serious problem in agriculture. However, the role of pathogens in determining the abundance of species in the wild is much less well understood; epidemics seem rarer, pathogens are less apparent, and effects on plant abundance are not always self- evident. Over the past ten years, Dr. Antonovics and his colleagues have used the anther-smut fungal disease of the plant white campion (Silene alba) as a model system to understand how pathogens impact natural populations. Individual plants differ in their susceptibility to the disease, but the genetic basis of this susceptibility is not understood. It is also not clear why populations do not become completely resistant; presumably the genes determining resistance have negative side-effects. This research will investigate whether one or several genes are involved in susceptibility, localize these genes using DNA markers, and investigate the causes of the resistance cost. Dr. Antonovics will also investigate whether the resistance is general to many pathogens or specific to just this one fungus. Identification of resistance genes will allow rigorous study of how these genes are distributed in nature, and of the role they play in rescuing plant populations from the disease. This research will improve understanding of how pathogens control plant populations, and will therefore be of direct relevance to biological weed control and conservation biology. It will also open the door for the possible use of these resistance genes in developing resistant transgenic crops.