With the exceptions of a small number of species, the genetic systems of tropical tree species suitable for planting in arid zones are scarcely known. A genetic system includes the species gene pool (with its development and activity in evolution and ecological genetics), the breeding unit (natural and artificial populations with characteristics gene frequencies) and the breeding system (mating or reproductive behaviour including techniques for the dispersal of gametes or seeds). The natural variation and taxonomy of selected tree species which have been studied by staff of the Commonwealth Forestry Institute in the field in Central America and Mexico are considered and the basis of the variation, as reflected by the type of breeding system employed, is analysed and discussed. The overall population structure as it is affected and constrained by a particular breeding system is considered; studies of pollen vectors, isozymes and other chemical evidence offer valuable techniques for elucidating such structures…..
Forest Ecology and Management (1986) 16 317-343 [10.1016/0378-1127(86)90031-9]