Understanding the molecular determination of quality traits in citrus fruit (MARTIN_J17ICASE)

自古以来，柑橘类水果的种植面积不断扩大；最著名的例子是橙子、柠檬、葡萄柚和酸橙。大多数商业柑橘品种是种间杂交品种，是无性繁殖的，这意味着育种和作物改良非常困难。柑橘类水果中最重要的特征之一是酸度，这在柠檬等品种中是一个积极的特征，但在真正的物种——柑橘中却是一个消极的特征。为了在分子水平上了解果实酸度的遗传决定因素，并在可能的情况下通过育种促进改进，我们正在研究柑橘果实酸度的遗传决定因素。通过开发酸度的功能性生物测定法，并利用这一方法探索来自不同柑橘种质资源的基因在决定果实酸度方面的活性，本研究将扩展我们对这一特性是如何决定的理解。我们的目标是与我们的工业伙伴合作，通过基因组编辑创造新的低酸度商业柑橘品种。这些低酸度品种可以用来生产低酸度、低添加糖的柑桔汁。

Citrus fruit has been cultivated in an ever-widening area since ancient times; the best-known examples are oranges, lemons, grapefruit, and limes. Most commercial citrus varieties are interspecific hybrids which are propagated vegetatively, meaning that breeding and crop improvement are very difficult. One of the most important traits in citrus fruit is acidity, which is a positive attribute in varieties such as lemon, but a negative trait in the true species, mandarin. To understand the genetic determinants of fruit acidity at the molecular level, and to facilitate improvement through breeding where possible, we are investigating the genetic determinants of fruit acidity in citrus. This studentship will extend our understanding of how this trait is determined, by developing a functional bioassay for acidity, and using this to explore the activity of genes from different citrus germplasm accessions in determining fruit acidity. We aim to create new low acidity lines of commercial citrus varieties by genome editing, in co-operation with our industrial partners. These low acidity varieties could be used to produce low acidity, low added sugar citrus juices.