Plant Biostimulants, Seaweeds Extract as a Model (Article Review)
Hayyawi Wewa Attia Al-Juthery, Hayder Abbas Drebee, Bassim M.K. Al-Khafaji, Rooa F. Hadi
Abstract
Abstract Plant biostimulants are classified as substances which have increased the positive effects on growth and productivity when applied to plants. Biostimulants are obtained naturally from various economically and environmentally viable sources, The plant biostimulants currently accepted include extracts of seaweed, humic substances (humic acids and fulvic acids), chitin and chitosan derivatives, amino acids, protein hydrolysates and microbes. Seaweed extracts and humic acids are widely studied for their role in plant growth-promotion, Seaweeds have been traditionally used in coastal Europe since time immemorial as fertilizers and soil conditioning agents. Seaweeds belong to Rhodophyta, Chlorophyta and Ochrophyta. Over the past two decades, seaweeds havebeen processed and marketed as seaweed extracts in various formulations for use in agriculture and horticulture. Seaweed extracts are rich in micro and macronutrients, polysaccharides, proteins, poly unsaturated fatty acids, polyphenols, phytohormones, and osmolytes. These compounds elicit multiple beneficial effects in plants, including enhanced seed germination and establishment, overall plant growth and productivity, resistance against biotic and abiotic stresses and increased post-harvest shelf lifeNumerous studies of the beneficial effects of seaweed extracts on crop plants and crop production, yield and productivity have been published.