Evaluating the efficacy of Moringa oleifera leaf extracts prepared using different solvents on growth, yield and quality of tomatoes and peppers

Purpose: The study aimed to explore different extraction methods, extraction solvents, as well as solvent/water mixtures that could potentially yield(s) the best growth-enhancing, yield- and quality-promoting effects of Moringa oleifera leaf extracts (MLEs), when applied foliarly to tomatoes and peppers. Research Method: This study was laid out following a complete randomized design with three replications. Foliar application of MLEs tested included: control, aqueous (hot water, MLE HW), aqueous (cold water, MLE CW), ethanolic (MLE ETH) and methanolic (MLE METH) extracts. These treatments were repeatedly sprayed onto the leaves of selected plants, from two weeks after transplanting in weekly intervals until fruit set. Findings: Foliar application of all MLEs significantly enhanced growth of both pepper and tomato plants compared with the control. MLE HW application positively affected yield parameters, followed by MLE ETH and MLE METH. All MLEs significantly enhanced the colour coordinate a* and TSS, excluding MLE CW. Carotenoids in red peppers were significantly higher, following all MLE treatments, excluding the MLE CW, while in red tomatoes MLEs enhanced lycopene and β-carotene content. The concentration of Vitamin C was also significantly enhanced by MLE application to peppers, while in tomatoes, only MLE METH and MLE ETH positively altered the fruit Vit C concentration. These results generally prove that MLE application could potentially be used to improve crop production and their nutritive value. Research limitations: There were no limitations identified. Originality/Value: The results obtained in this study highlight the potential MLEs, particularly hot water MLE, to enhance growth, yield and nutritional quality of pepper and tomato, without compromising human health and environmental sustainability.