The health of the cannabis plant is a very important part of cannabis cultivation. This is why a great deal of consideration and in-depth research are required to understand the best nutrients that can promote plant health. The seaweed extract in particular is rich in many beneficial nutrients that can help your cannabis reach its optimal size and grow healthy.
Especially with the current prevalence of extreme weather conditions, such as drought and flooding, the healthy growth of cannabis plants is even more critical. Under drought conditions, cannabis plants treated with seaweed extracts, algae extracts from Ascophyllum nodosum, ecklonia maxima seaweed extract and sargassum seaweed fertilizer showed significantly enhanced drought resistance, primarily manifested in higher leaf water content, improved photosynthetic efficiency, and reduced oxidative damage.
These effects are primarily attributed to the synergistic effects of active ingredients in seaweed extracts, including betaines, polysaccharides (such as fucoidan and alginic acid), and trace plant hormones.
1. Maintaining Leaf Water and Osmoregulation
Osmoprotective Effect of Betaine:
Seaweed extracts are rich in glycine betaine (GB), a compatible solute that helps plant cells maintain osmotic balance under drought stress. Betaine stabilizes protein structure and protects the integrity of photosynthetic system II (PSII), reducing dehydration damage to chloroplasts and thereby improving the water-holding capacity of cannabis leaves.
Water-Retention Effect of Polysaccharides:
Seaweed polysaccharides (such as alginic acid and fucoidan) form hydrophilic colloids, reducing water evaporation and promoting water absorption by roots. Experiments have shown that hemp treated with seaweed extracts under drought conditions exhibited a 10-20% increase in leaf relative water content (RWC) compared to controls.
2. Enhanced Photosynthetic Efficiency
Protecting Photosynthetic Pigments and Photosystem II (PSII):
Drought typically leads to chlorophyll degradation and decreased photosynthetic rate. The betaine and polysaccharides in seaweed extracts can reduce the damage to photosynthetic machinery caused by reactive oxygen species (ROS). Studies have shown that seaweed-treated hemp maintains high chlorophyll content (SPAD value) and maximum photochemical efficiency (Fv/Fm) under drought conditions.
Regulating Stomatal Behavior:
Abscisic acid (ABA) analogs and cytokinins in seaweed extracts may participate in stomatal regulation, helping hemp reduce water loss during drought and rapidly restore stomatal conductance when water is restored.
3. Activation of the Antioxidant Defense System
Reducing Oxidative Damage:
Drought stress induces the accumulation of ROS (such as H₂O₂ and superoxide anions), leading to membrane lipid peroxidation (increased MDA levels). Seaweed extract can enhance cannabis’ antioxidant enzyme systems (such as SOD, CAT, and POD), reduce MDA levels, and thus reduce cell membrane damage.
Regulation of Secondary Metabolites:
Some studies have found that seaweed extract may indirectly enhance drought resistance by activating the jasmonic acid (JA) and salicylic acid (SA) signaling pathways, promoting the accumulation of antioxidant cannabinoids (such as CBD) in cannabis.
Effective use of seaweed extract can improve cannabis cultivation and enhance profitability. In practical cultivation, the concentration, frequency, and method of seaweed extract application should be determined based on the timing and severity of drought and the needs of cannabis plants at different growth stages to maximize its activation of the cannabis plant’s antioxidant defense system. This, in turn, improves the plant’s ability to survive adverse conditions and enhances yield quality, providing strong support for the sustainable development of the cannabis industry. Scientific application of Dora’s biostimulants, especially KelpReal seaweed extract, for better sustainable development and organic agriculture stress resistance solution.