ASSESSMENT AND MANAGEMENT OF PLANT GENETIC DIVERSITY - CONSIDERATIONS OF INTRASPECIFIC AND INTERSPECIFIC VARIATION

Effective management of plant genetic diversity incorporates agricultural development as a critical element of conservation. Advancement of renewable production of food and other plant-derived essentials of human culture must be compatible with and supportive of stewardship of those biological resources basic to agriculture. Balance must be struck between the accumulation of short-term dividends contributing to an enhanced quality of life and maintenance of insurance consisting of representative and well-characterized genetic diversity for the future. Plant genetic diversity is complex in theory and practice. To best understand plant genetic diversity, it is essential to consider variation as richness and distribution at both the intra- and interspecific levels. If a species is defined as a potentially interbreeding population, then the diversity existing in the gene pool is manifested as its resilience in response to selection, whether natural or artificial. Depending on the state of our genetic understanding of a taxon, genetic diversity may be considered at different organizational levels: gene pool, population, individual, genome, locus, and DNA base sequence. Concepts and techniques of classical genetics must be consolidated with recent progress in population, systematic and molecular biology. This synthesis will allow for a clearer characterization of both intra- and interspecific variation of wild and domesticated plants and greatly enhance conservation and utilization of plant genetic resources for the future.