The Importance of Genetic Studies

A genetic study can often assist in making a critical management decision or preparing an effective restoration or management plan. However, whether the genetic study is a quick assessment of samples of plant material, or a longer-term and more elaborate project, attention to some basic principles can mean the difference between acquiring useful information or simply wasting time and other resources. Before commencing any genetic study or investigation, three issues should be addressed:

materials for restoration, determining the ploidy level of certain plants or populations, monitoring changes in genetic diversity over time, identifying plants as belonging to the same or different clone or population, and so on (see, for example, Volume 2). Likelihood of success: There may be a range of possible outcomes for a genetic study, depending on the context and the amount of information already available for the species. For example, if the objective is to identify the origin of plants in a plantation or restoration project, the chances of a definitive result are increased when: there are good planting or nursery records that limit the number of possible sources; and there are plant samples available from all of the possible sources; there are genetic markers already developed that can distinguish one source population from another. Although there are usually genetic differences of some sort among populations, the ability to detect them varies widely with the type of genetic marker developed and used and the number of loci that can be considered. Sometimes genetic differences among populations are quantitative (for example, the frequencies of certain alleles differ among populations) rather than qualitative (for example, there are alleles that are specific to a population and thus are diagnostic; these are called ‘private alleles’). So in the former situation, the result of a genetic study may be expressed in terms of probability rather than definitively. The value to