DISSERTATION RESEARCH: Evolution and Development of Petals in Aizoaceae (Caryophyllales)

开花植物花瓣的起源长期以来一直是植物学家们猜测和争论的主题。传统理论认为小苞片（起源于叶状器官）和andro花瓣（起源于绝育的男性器官）有多个独立的进化起源。最近，控制花瓣形成的深度保守遗传程序的发现表明，所有花瓣状器官可能受到类似的遗传控制。这一假设将通过检查控制Aizoaceae中花瓣形成的遗传途径来验证。Aizoaceae是一组多肉植物，具有两种非常不同的花瓣状结构，来自叶片状器官或不育的雄性部分。花瓣是一种极其重要的进化创新，毫无疑问，它有助于开花植物成功地殖民陆地生态系统。花瓣对农业也有重要意义，因为许多作物依靠花瓣来吸引传粉者，以确保受精、结实和良好的作物产量。这项研究，连同正在进行的对其他开花植物群体的研究，将有助于了解花瓣是如何、为什么以及何时进化的。在阐明花瓣形成的遗传机制时，将有可能更好地理解这种进化创新的影响。此外，这些知识还可用于农业品种的遗传改良。

The origin of the petal in flowering plants has long been a subject of speculation and controversy among botanists. Traditional theories suggest multiple independent evolutionary origins of bracteopetals (derived from leaf-like organs) and andropetals (derived from sterilized male organs). More recently, the discovery of deeply conserved genetic programs controlling petal formation suggests that all petal-like organs may be under similar genetic control. This hypothesis will be tested by examining the genetic pathways controlling the formation of petals in Aizoaceae: a group of succulent plants that possess two very different types of petal-like structures derived from either leaf-like organs or sterilized male parts. Petals are an extremely important evolutionary innovation that has undoubtedly contributed to the success of flowering plants in colonizing the terrestrial ecosystem. Petals are also of major significance for agriculture as many crops rely on petals to attract pollinators to ensure fertilization, fruit set and good crop yields. This study, in conjunction with ongoing studies in other groups of flowering plants, will help to understand how, why and when the petal evolved. In elucidating the genetic mechanisms underlying petal formation it will be possible to better appreciate the impact of this evolutionary innovation. Furthermore, this knowledge could be used to genetically improve agricultural cultivars.