Effect of seed irradiation with gamma ray on some physiological properties and biochemical parameters of plants in two species of Bromus inermis and B. tomentellus

This study was conducted to investigate the effects of different treats of gamma ray doses including 15, 20, 30, 50, 100 and 150 gray, on Bromus inermis and B. tomentellus seeds. The efficiency of gamma ray to stimulate the growth and increasing the plant tolerance and physiological stability in daily temperature and water supply fluctuations was evaluated by measuring some parameters including total protein, proline and chlorophyll content. A completely random design was used to collect the data from irradiated seeds that were sown in greenhouse condition. The results showed that the 15 gray doses caused the most positive effects on chlorophyll content and physiological condition of B. inermis. The most positive effect on B. tomentellus physiological conditions was observed in 30 gray treatment. Using 100 and 150 gray doses treatments decreased the seed growth of the both species through its negative effects on photosynthetic rate and evapotranspiration of the species. Soluble protein content in the both species increased as gamma ray intensity increased. Proline concentration of B. inermis seeds was also decreased significantly (p<0.01) after using gamma ray treatments. The proline content of B. inermis seeds in control and 15 gray treatments did not varied significantly but it was decreased in higher gamma ray intensities (from 20 gray intensities to higher doses). The results indicated that the gamma ray application had no significant effects on proline content of B. tomentellus. In conclusion, the 15 gray treat for B.inermis and 30 gray treat for B. tomentellus can enhance the seed growth of the both species.