GENETIC APPROACHES IN PLANT PHYSIOLOGY

The use of genetics in plant biology aims at the physiological and mol ecular genetical characterization of the phenotypic variation for the trait under study. Efficient mutant and gene isolation procedures have been developed for a number of plant models such as Arabidopsis thali ana. For this, the map position of the genes and insertion mutagenesis are used. The latter also allows the characterization of genes that a re not easily recognized in mutant approaches, by using enhancer or ge ne-trapping procedures and reverse genetics. In addition to mutants, n atural variation present among wild and cultivated varieties of a spec ies provides an important source of genetic variation. The use of mole cular markers, advanced mapping populations and specific cytogenetic s tocks in case of polyploids, enables a detailed characterization of su ch natural variation even when it is of a quantitative and polygenic n ature. Examples of the various genetic approaches are given.