Variation in biochemical and antioxidant attributes of Raphanus sativus in response to foliar application of plant leaf extracts as plant growth regulator

The present study was aimed to appraise the variations in biochemical, antioxidant and nutritional attributes of radish (Raphanus sativus L.) under foliar application of plant leaf aqueous extracts i.e., mulberry leaf extract (MLE), brassica leaf extract (BLE), sorghum leaf extract (SLE) and moringa leaf extract (MoLE) as natural growth regulators. Samples were collected after three sprays of extracts and analyzed. Total phenolic constituents were determined using Folin–Ciocalteu reagent method, whereas antioxidant potential was evaluated by 1,1 diphenyl-2-picrylhydrazyl radical radical scavenging and reducing power assays. Results revealed that application of MLE, BLE, SLE, and MoLE not only improved growth, but also enhanced biochemical and antioxidant activities. Foliar spray of MoLE furnished relatively three folds higher amounts of extractable bioactive compounds (37.65 ± 0.94%), phenolic constituents (54.51–182.71 mg GAE/g f.w). The radical scavenging capacity (RSC) and reducing potential were also enhanced considerably. Furthermore, the moisture, dietary fiber, crude protein, and carotenoids were also enhanced in response of foliar spray of plant extracts. From results, it is concluded that plant extracts are effective sources of natural growth regulars and might be useful for the production of vegetables with improved nutritional value and antioxidant activity.