BACKGROUND

Current scenarios of global climate change predict a significant increase in ultraviolet B (UV-B) and tropospheric ozone (O₃) in the near future. Both UV-B and O₃ can have detrimental effects on the productivity and yield quality of important agricultural crops. The present study was conducted to investigate the individual and interactive effects of supplemental UV-B (sUV-B) (ambient + 7.2 kJ m⁻² day⁻¹) and O₃ (ambient + 10 ppb) on the yield and oil quality of two cultivars of linseed (Linum usitatissimum L.).

RESULTS

The mean monthly ambient O₃ concentration varied from 27.7 to 59.0 ppb during the experimental period. O₃ affected fruit formation, while sUV-B was mainly responsible for ovule abortion. Seed sugar and protein contents showed maximum reduction in O₃-treated plants, while mineral nutrient levels were most affected by sUV-B + O₃ treatment. Rancid oil of low nutritional quality and containing long-chain fatty acids was favoured along with a decrease in oil content.

CONCLUSIONS

sUV-B and O₃ individually as well as in combination caused deterioration of the yield and quality of oil and seeds of linseed. However, the individual effect of O₃ was more damaging than the effect of sUV-B or sUV-B + O₃, and cultivar T-397 performed better than Padmini.