檀香是我国南方地区近年来大力推广种植的重要珍贵树种，其主要的经济价值在于芳香气味的心材和从心材中提取的精油，然而在正常生长条件下檀香约需10年甚至更长时间才开始形成心材，因此开展促进檀香心材形成及其代谢途径的研究对于缩短种植周期，提高林地经济效益具有重要的现实意义。本项目以无心材的檀香植株为研究对象，通过树干填充乙烯、二氧化碳和氮气等气体，观测不同气体诱导檀香心材的形成情况，并分析各处理之间诱导形成心材的比例、心材成分及结构特征、心材精油含量和成分组成等指标之间的差异，结合各代谢途径的重要特征代谢物（酚类、萜类）的含量和酶活性（苯丙氨酸解氨酶和过氧化物酶）的变化规律，探明檀香心材形成的代谢途径。研究结果不仅有助于推动我国檀香种植业的快速发展，还丰富了心材形成理论的研究内容，为更深入了解檀香心材的形成过程及机理提供理论依据和技术基础。

Sandal (Santalum album), one of the most important tree species promoted for large area planting in southern China in recent years, is highly valuable for its aromatic heartwood and the essential oil distilled from its fragrant heartwood. Heartwood formation is a very complicated process in sandal, and it will take 10 years or more to form aromatic heartwood generally, so study on the inducing heartwood formation and the corresponding metabolism pathway of sandal is of great importance on shorten the rotation period and increasing economic benefit of sandal plantation. In this study, we use ethylene, carbon dioxide and nitrogen to induce heartwood formation on young sandals through a stem filling method, and try to find out if and how those gases affect heartwood formation based on the metabolism pathway, finally, determine the metabolism pathway of sandal heartwood formation through analyzing the differences on the volume of induced heartwood, heartwood ingredients, essential oil content and oil composition between each gas treatment, at the same time, the changes on concentration of some characteristics products during heartwood formation metabolism such as phenols, terpenoids, activities of phenylalanine ammonia-lyase(PAL) and peroxidases(POD) were also monitored to further confirm the metabolism pathway. The results of this study can not only be helpful for the fast development of sandal plantation in southern China, but also be useful for the supplement of heartwood formation theory, which can provide technological support for the further study on the process and mechanism of sandal heartwood formation.