Role of gamma irradiation in regulation of NO3 level in rocket (Eruca vesicaria subsp. sativa) plants

The changes in the growth indices and certain metabolic activities in response to different doses of γ-irradiation (0, 20, 50, 100, and 200 Gy) were studied, using rocket seedlings. The total yield, seed mass, and essential oil content increased significantly by 20 Gy dose of γ-irradiation as compared with the control samples. In addition, total sugars, total free amino acids, total soluble phenols, kinetin, GA₃, nitrate reductase activity, and total protein increased significantly at 20 Gy dose. Meanwhile, NO₃ content decreased significantly at 20 Gy dose. The nitrogen and potassium content increased at the same dose of gamma rays of 20 Gy. While the phosphorus content showed no significant effect at all the γ-irradiation doses used. The results obtained in this work revealed that the most effective dose was 20 Gy of gamma rays. It was suggested that pretreatment of rocket seeds before planting with 20 Gy dose of γ-irradiation, may oppose the harsh effect of NO₃ accumulation and increased the quality and quantity of rocket yield. Published in Russian in Fiziologiya Rastenii, 2006, Vol. 53, No. 2, pp. 215–219. The text was submitted by the author in English.