Effect of Seaweed Extract on Droughty Resistance of Sugarcane Seedling

A hydroponic experiment was conducted to explore the effects of various rates of seaweed extracts (prepared from brown alga) on sugarcane growth and physiological response under stimulated drought stress. Yuetang 94-128 was selected based on seedling growth under drought and were planted in pots containing 10 liter of Hoagland solution. The seedlings were subjected to drought levels using 0% or 10% PEG6000 mixed with Hoagland solution. Three seaweed extract treatments consisting of 0%, 0.5%, and 1% (V/V) of the seaweed extract level in full strength Hoagland solution were applied. The activity of peroxidase (POD), superoxide dismutase (SOD) and catalase (CAT), the content of MDA and electric conductivity (EC) of leaves were measured after 3 days with treatments; the leaf dehydration rate (LDR), the relative water content (RWC), plant height and fresh weight were measured after 10 days with treatments. The results showed that the antioxidant enzymes activity in sugarcane leaves of POD, SOD and CAT were improved, the MDA content, the electric conductivity and the leaf dehydration rate were significantly decreased, while the relative water content, plant height, biomass, leaf SPAD value were greatly increased with the application of seaweed extract under drought stress (p < 0.05), which implied that seaweed extract has a potential for drought-resistant modulation.