Investigation on the Effects of UV Radiation on Physiological Characteristics of Moringa oleifera Lam. in vitro and in situ

Abstract

Moringa oliefera seeds were treated with UV light type A, B and C for 30 minutes. Seedlings length, number of plants, number of axillary buds, number of adventitious buds and number of apical buds were recorded 34 days after sowing the treated seeds in addition to the control in vivo. Sterilized seeds were cultured in vitro on MS agar medium containing 4.0 mg/l BA for seed germination, then shoot explants were cut into small pieces and placed on the MS agar medium supplemented with 0.5 mg/l BA and 2.5 mg/l 2, 4-D. The percentage of callus induction and callus fresh weight were determined about six weeks after inoculating. Proline and carbohydrate concentrations were also determined for intact plant and callus cultures. Results showed that the physiological parameters studied in situ reduced significantly at UV-B recording 1.5, 1.8, 3.4, 2.8 and 19.3 cm No. germinated plants, No. Adventitious buds, No. axillary buds, No. apical buds and seedlings height respectively. UV-B recorded the highest mean values in relation to percentage of callus induction, callus fresh weight and proline concentration (100%, 112 mg and 9.7 µM/g respectively) compared to the control (72.3%, 93.3 mg and 7.3 µM/g respectively). A significant reduction in the mean carbohydrate concentration was observed in all UV treatments in both intact plants and callus cultures compared with control.