Bio effectors, also known as plant biostimulants, are increasingly used in agriculture due to their ability to enhance plant growth and improve resistance to environmental stress. These substances or microorganisms, when applied to plants or the rhizosphere, stimulate natural processes that support nutrient uptake, improve nutrient use efficiency, help plants cope with abiotic stress, and enhance overall crop quality regardless of their direct nutrient content. Bio-stimulants are effective in both agricultural and horticultural systems. Conventional farming practices that rely heavily on chemical inputs are degrading soil health and disrupting ecosystem balance. To promote sustainable crop production, the agricultural sector must adopt environmentally friendly alternatives an area where biostimulants show great promise. Key types of plant biostimulants include plant or animal protein hydrolysates, nitrogen-containing compounds, humic substances, seaweed extracts, biopolymers, chitosan, microbial derivatives, phosphites, and silicon. Their protective and growth-promoting effects vary based on the specific compound and crop, but generally involve enhanced physiological processes and improved plant morphology. These benefits can include better root development, increased nutrient absorption, higher seed germination rates, improved crop establishment, enhanced cation exchange capacity, detoxification of heavy metals, and optimized regulation of stomatal conductance and transpiration. Biostimulants products may contain single or multiple active ingredients, and formulations with diverse components often exhibit synergistic effects. Overall, biostimulants represent a sustainable, long-term solution for increasing crop productivity while minimizing environmental impact.
Abiotic stress, Biostimulants, Micro-organisms, Nutrient use efficiency
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