DNA damage and repair in higher plants

The principal mechanics of DNA damage and repair in higher plants and their relation to chromosome and genetic mutation induction by chemicals and radiation are reviewed. Photoreactivation of DNA in cells of higher plants and in chloroplasts of algae are discussed. Photoreactivation of cyclobutane-type pyrimidine dimers is described. Excision repair in plant DNA of damage induced by ultraviolet radiation and ionizing radiation is also described. Formation and repair of single-strand DNA breaks and repair of replication due to chemical mutagens and carcinogens are discussed. Evidence is presented for the presence of photoreactivation, excision repair of pyrimidine dimers, repair synthesis, rejoining of single-strand DNA breaks, as well as liberation of alkylated guanines from the DNA of plants. Data are presented illustrating the inhibition of repair processes by caffeine and EDTA. The interrelationships between aging and repair activities in plants remains unclear