Response of the photosynthetic apparatus of corn (Zea mays) to presowing seed treatment with γ-rays and ammonium molybdate

The effects of low doses of γ-radiation on water or molybdenum-soaked seeds on the photosynthetic apparatus of the resultant seedlings were studied. Irradiation of water-soaked seeds increased both the content and stability of the chloroplast pigments, chlorophylls a and b and the carotenoids. Moreover, it increased the protein:chlorophyll ratio, the dehydroascorbic, and to a greater extent, the ascorbic acids as well as the photochemical activity of the chloroplasts. Irradiation of molybdenum-soaked seeds increased all the above mentioned parameters, except the content of chlorophylls. The 500 R exposure was generally more effective in producing seedlings better equipped with an active photosynthetic apparatus. (author)