CHANGES IN MAIZE POLLEN CAROTINOIDS INDUC ED BY INTENSE DISCONTINUOUSWHITE-LIGHT AND THE PROBLEM OF MUTAGENESIS

Prehybridization short-term illumination of maize pollen of the Mangel sdorf tester (MT) by intense discontinuous white light (IDWL) with the energy of 3x10(9) to 3x10(10) joule/m2 results in enhanced biosynthes is, photooxidation, transformations and photosensitization of carotino ids, ans formation of peroxide and hydroxide free radicals (FR). Photo sensitized carotinoids activated gene expression, while FRs exert muta genic effect. Hybridization of the IDWL-illuminated pollen caused appe arance of ca. 5% TM with dominating untypical reccessive characters ne ver observed earlier. Such hybridization introduce additional genotype alterations without affecting significantly many practically useful p roperties. Being the ecologically purest and the most natural factor f or plants, photomutagenesis is a highly efficient, soft, and easily ac cessible tool in genetic selection.