Effects of Different Selenium Concentrations on Photosynthetic Pigment Contents of Solanum nigrum

A pot experiment was carried out to study effects of different selenium concentrations (0, 5, 10, 25, 50, 75, and 100 mg/kg) on the photosynthetic pigment contents of Solanum nigrum. The results showed that all concentrations of selenium inhibited the chlorophyll a, chlorophyll b and carotenoid contents of S. nigrum. The selenium concentrations order of S. nigrum chlorophyll a, chlorophyll b and total chlorophyll contents contents from large to small were all ranked: 0 mg/kg, 10 mg/kg, 25 mg/kg, 5 mg/kg, 50 mg/kg, 75 mg/kg, and 100 mg/kg. Compared with the 0 mg/kg, only the selenium concentration of 10 mg/kg had little effect on the chlorophyll b and carotenoid contents of S. nigrum. These results indicated that high concentrations of selenium stress have significant inhibitory effects on the photosynthetic pigment contents of S. nigrum which were not conducive to the growth of S. nigrum. When the concentration of selenium is 10 mg/kg, the inhibitory effects on the photosynthetic pigment contents of S. nigrum were the lowest.