Exogenous application of Moringa leaf extract or dopamine enhances resistance to drought stress in Brassica napus L

Drought stress is among the serious concerns facing agriculture sector. Water scarcity or drought stress has been identified as a severe limitation on the productivity of canola, a widely cultivated oil crop worldwide. Mediating many physiological and biochemical processes in several crops under favorable or unfavorable conditions, Moringa leaf extract (MLE) serves as unexpensive, eco-friendly, and novel bioenhancer, while dopamine (DA) serves as a potential antioxidant. The current investigation was determinate the efficient of Moringa leaf extract or dopamine as exogenous application to mitigate the negative effects of water scarcity in canola plants water-stressed (60% field capacity) and control (100% field capacity). The findings indicate that drought stress considerably reduced all growth traits, yield attributes, membrane stability index (%) and relative water content. However, the treatment with 10 g/L Moringa leaf extract or 200 mM dopamine attenuated the stress created by water deficit and ameliorated the aforementioned characters. Water deficiency stress greatly increases osmo-protectants (total soluble sugar and free proline contents) and CAT and SOD enzyme activities. Dopamine was more efficient in alleviating drought stress than Moringa leaf extract.