Biostimulants from Rosa alba L. optimize growth and physiological processes of Zea mays L

Introduction Contemporary agriculture encounters significant challenges due to the excessive application of synthetic pesticides and fertilizers, leading to increased environmental and health issues. Plant-based biostimulants represent a viable solution for improving crop productivity with reduced ecological impacts. Methods In this work, we examined how the growth and metabolic responses of Zea mays L. seedlings were affected by dose-dependent powdered leaf and stem biomass of Rosa alba L. (5, 10, and 15 g.kg −1 of soil). Results The findings indicated that increased powdered stem biomass doses, specifically 10 g and 15 g, markedly improved growth factors including root length, leaf quantity, and shoot length, whereas a little influence was observed in root quantity. The 10 g treatment was identified as the most balanced dosage, facilitating significant root and shoot development, whereas the 15 g treatment predominantly enhanced root elongation. Enhancements in photosynthetic pigments, such as chlorophyll a, b, total chlorophyll, and carotenoids, observed under the 10 g and 15 g treatments, suggest increased photosynthetic efficiency and improved photoprotection mechanisms. Biochemical analysis indicated increase in protein and sugar levels with elevated treatment doses, demonstrating improved metabolic activity and nutrients assimilation. In contrast, proline content, recognized as a stress marker, exhibited a progressive decrease with higher powdered biomass concentrations, indicating diminished stress levels and enhanced physiological stability. Principal Component Analysis (PCA) identified photosynthetic pigments and sugar content as the primary factors contributing to treatment-induced variability, with proline serving as a specific indicator of stress response. Discussion This study presents strong evidence that R. alba powdered biomass, especially at optimized doses, function as new effective natural growth enhancers. These R. alba biostimulants enhance plant growth, photosynthetic capacity, and metabolic stability, while also mitigating stress, thereby providing a sustainable and environmentally friendly alternative to synthetic agrochemicals.