Biostimulants: An overview and role in sustainable wheat production

Wheat (Triticum aestivum L.) is extensively cultivated across the globe and serves as an essential crop for sustaining food systems and nutritional security, with pronounced importance in developing countries. However, intensive reliance on chemical fertilizers to sustain high wheat productivity has led to soil degradation, environmental pollution, and declining nutrient use efficiency. In the scenario of climate change and increasing biotic stress and abiotic stress, there is an need of immediate attention for sustainable alternatives that can enhance crop performance while preserving soil health. Biostimulants have emerged as promising tools in sustainable wheat production due to their potential to improve plant physiological processes, nutrient uptake efficiency (NUE), grain quality, yield and stress tolerance when applied in small quantities. This review synthesizes current knowledge on the types of biostimulants, including microbial (rhizobacteria, Trichoderma spp. and Arbuscular mycorrhizal fungi) and the non-microbial sources (seaweed extracts, humic products and protein hydrolysates substrances) and their mechanisms of action in wheat. Evidence from recent studies demonstrates that biostimulants positively influence wheat growth, yield attributes, photosynthetic efficiency, root architecture, soil nutrient availability and microbial activity, while enabling partial replacement of chemical fertilizers under integrated nutrient management systems. The review highlights the role of biostimulants in improving wheat productivity, soil quality, and resilience to environmental stresses, thereby supporting sustainable and climate-smart agricultural practices. Continued research, standardization, and field-level validation are essential to fully exploit their potential in large-scale wheat cultivation.