A survey of the effect of synergism between rhizosphere and diesel-degrading bacteria on some growth and biochemical factors of Zea mays in diesel polluted soils

Soil pollution by oil compounds is one of the most common environmental problems that induce oxidative stress in plants. In this research, for investigate the synergism between soil rhizosphere and diesel degrading bacteria on some growth and biochemical factors of Zea mays (640 and 704) in diesel polluted soils, four different treatments were designed. Various physiological and microbial factors were assayed. The results showed that root and shoot length and total chlorophyll in presence of treatments in both varieties of Z. mays were significantly decreased in comparing to the control plants. Stress caused a significant increase in carotenoids and malondialdehyde contents in diesel treatment and diesel and Peseudomonas fragi bacteria treatment in comparing to control in both varieties. The anthocyanin content and protein were significantly increased in comparing to control. This stress caused an increase in the numbers of degrading and heterotrophic bacteria and dehydrogenase enzyme. Therefore, we can say that diesel treatment decreased the growth of Z. mays and adding the degrading bacteria improved diesel depressing effect on plant growth.