Dissertation Research: Domestication in a Tropical Fruit Tree

驯化发生在人类从野生种群中选择和培育植物的过程中。 在许多作物品种中，采用高产、统一的栽培品种导致放弃遗传变异的本地品种。 众所周知，在驯化的这些后期阶段，随着高产作物的发展，遗传多样性丧失;然而，在驯化的早期阶段（在密集的植物育种之前）遗传变异的命运尚不清楚。 本研究探讨了热带果树，紫色mombin（Spondias purpurea L.）的驯化过程，这被认为是在驯化的早期阶段。 DNA序列数据将被用来查明紫色mombin的地理起源，并检查栽培和野生种群之间的关系。 将量化遗传变异，以确定在栽培种群中捕获的总变异比例。 最近，由于人们越来越担心栽培物种缺乏遗传多样性，人们的注意力重新集中在作物及其野生亲缘植物上。 这项建议将导致热带果树遗传变异的起源，分布和数量的全面评估，为我们栽培植物的驯化所涉及的进化过程提供见解。 栽培植物种群的历史知识将产生制定保护战略所需的关键信息。

Schaal0105134Domestication occurs as humans select and cultivate plants from wild populations. In many crop species, the adoption of high-yielding, uniform cultivars has resulted in the abandonment of genetically variable, indigenous varieties. It is well known that during these later stages of domestication, genetic diversity is lost as high-yield crops are developed; however, the fate of genetic variation during the early stages of domestication (prior to intensive plant breeding) is not known. This study examines the process of domestication in a tropical fruit tree, the purple mombin (Spondias purpurea L.), which is believed to be in the early stages of domestication. DNA sequence data will be used to pinpoint the geographic origin of the purple mombin, and to examine relationships among cultivated and wild populations. Genetic variation will be quantified to determine the proportion of total variation captured in the cultivated populations. Recently, much attention has refocused on crops and their wild relatives as concerns mount about the lack of genetic diversity in cultivated species. This proposal will result in a comprehensive assessment of the origin, distribution, and amount of genetic variation in a tropical fruit tree, providing insights into the evolutionary processes involved in the domestication of our cultivated plants. Historical knowledge of cultivated plant populations will yield critical information required for developing conservation strategies.