The evolution of plant populations can be affected by natural selection, gene flow (genes entering the population from other populations), and genetic drift (chance events due to small population size). In order to understand how evolution proceeds, one must know how these different forces operate together. All of these are affected by which individuals are transmitting genes to the next generation. However, because movement of pollen from plant to plant is nearly impossible to follow, determination of which individuals are supplying genes is difficult. The technique of electrophoresis makes it possible to determine if a given individual could be the father of a particular seed. By applying this technique to seeds produced by all individuals in a population, a determination of which individuals are supplying genes to progeny can be made. Knowing the parentage of seeds will help explain how different forces affect the evolution of a population. In addition, information on how genes move through a population can be applied to agricultural systems. This informaton could be very beneficial when breeding for specific traits or when trying to reduce the amount of gene movement into or out of a particular area.
