Although we are currently facing the danger of ultraviolet radiation from solar emissions due to the weakening of ozone layer protection, their interaction with vegetation could have useful applications. We performed experiments on a widely cultivated plant species, Cucurbita pepo, by applying controlled UV-C radiation exposure to freshly germinated seeds. Microscopic images were captured using a high-resolution video camera on root tissue samples prepared according to a well-established protocol. Biochemical analyses were focused on the representative antioxidant enzymes, superoxide dismutase and catalase, as well as on photosynthetic pigments. The cytogenetic investigations revealed various chromosomal changes, mainly chromosome bridges, expelled and lagging chromosomes and C-metaphases, as well as combinations thereof. The biochemical analyses revealed mainly reduced superoxide dismutase activity but greatly increased catalase activity, together with similar, although less extensive, variations in malondialdehyde content and progressive positive variations in soluble proteins. Stimulated photosynthetic efficiency was also found for some seedling samples, based on the ratio of chlorophyll concentrations, which seems to be consistent with the statistical results on the stem length of seven-day-old seedlings. Thus, studying controlled UV-C irradiation of seeds could reveal possible applications in the mutagenesis of plants of agro-industrial interest.