Water stress stands as a formidable challenge in agricultural production. Drought conditions impede crops’ water absorption, weaken photosynthesis, and even disrupt flowering and fruiting processes, ultimately leading to significant yield reductions. However, seaweed fertilizer, a natural biostimulant, has emerged as a promising solution due to its rich composition of polysaccharides, mannitol, cytokinins, abscisic acid, and antioxidant substances, all of which effectively boost crop drought tolerance.
The mechanisms by which seaweed fertilizer exerts its effects are multi – faceted. Firstly, it promotes root development, enhancing the crop’s ability to absorb water. A well – developed root system allows plants to penetrate deeper into the soil and access more water sources. Secondly, polysaccharides and mannitol in seaweed fertilizer stabilize cellular osmotic pressure, reducing water loss caused by transpiration. Additionally, seaweed fertilizer regulates stomatal opening and closing, minimizing water evaporation while maintaining photosynthesis, thus improving water use efficiency.
Drought not only affects water uptake but also exacerbates the accumulation of free radicals in plants. These free radicals cause cellular damage and accelerate crop senescence. Fortunately, the antioxidant components in seaweed fertilizer can scavenge free radicals, mitigating cellular damage caused by drought, delaying plant aging, and increasing survival rates. Moreover, seaweed fertilizer induces the expression of plant stress – resistant genes and promotes the synthesis of stress – resistant substances such as proline, enabling crops to maintain good growth conditions in arid environments.
There are several application methods for seaweed fertilizer, including foliar spraying, root drip irrigation, and seed treatment. During drought or periods of unstable water supply, foliar spraying can quickly replenish active substances in plants and reduce water loss. Root drip irrigation helps strengthen the root system and improves water absorption capacity. Seed treatment, on the other hand, increases germination rates, equipping seedlings with strong drought tolerance from the early growth stage.
In an agricultural environment where water resources are becoming increasingly scarce, the rational application of seaweed fertilizer can significantly improve crop drought tolerance, prevent excessive yield losses, and contribute to the sustainable development of agriculture. By harnessing the power of this natural biostimulant, farmers can safeguard their crops against the threats of water stress and ensure more stable and sustainable agricultural production.