引言森林遗传学是一个新的研究领域,对于绝大多数树种来说,其遗传学方面的知识仍了解甚少。在美国,大多数应用于树木的改良程序仍局限在对天然林分的选择和繁育水平上,甚至最老的育种程序(仅30年代用)仍然在第二代育种程序中应用(Guries、Kang 1981)。大约在10年前,同功酶第一次应用于森林树种的遗传学研究方面(Feret、Bergmann 1976),现 INTRODUCTION Forest genetics is a new field of research, and for the vast majority of tree species, little is known about its genetics. In the United States, most of the improved procedures applied to trees are still limited to the selection and breeding of natural stands, and even the oldest breeding programs (used only in the 1930s) are still used in second-generation breeding programs (Guries, Kang 1981). About 10 years ago, isozymes were first applied to the genetic studies of forest tree species (Feret, Bergmann 1976), now