Growth photosynthetic activity and antioxidant responses of mycorrhizal and non-mycorrhizal bajra (Pennisetum glaucum) crop under salinity stress condition

Abstract

Arbuscular mycorrhizal (AM) fungi alleviating the adverse salt effects on growth was tested in bajra (Pennisetum glaucum). Towards this objective we analyzed the photosynthetic activity, proline, phosphatase activity and various antioxidant enzymes such as peroxidase, catalase and superoxide dismutase at 0, 100, 200 and 300 mM salinity levels in AM inoculated and non inoculated bajra plants. Total chlorophyll content was significantly higher in moderate salinity condition in AM fungus (Glomus fasciculatum) inoculated plants, which lead to increase in growth and nutrient uptake capacity of mycorrhizal plants. Antioxidant activity was either increased or decreased due to responses to different salinity stress conditions. Proline accumulation was induced by salt and it was more in shoot of non-AM inoculated plants, but in roots proline accumulation was higher in AM plants at all levels of salinity. This work suggests that the AM fungus helps bajra plants to perform better under moderate salinity levels by enhancing the antioxidant activity and proline accumulation as compared to non-mycorrhizal plants.