Seaweed-derived bio-stimulant improves growth and salt tolerance of radish varieties under saline conditions

The potential of macroalgae as biostimulants in agriculture and biotechnology is getting attention because they enhance the growth of various edible crops. Thus, the current study deals with the potential of marine algae (Enteromorpha intestinalis) seaweed (SW) powder for its effect on seed germination, growth, biochemical parameters, and pigment characteristics of Radish varieties (40 days, R-1 and Radish variety Minu Early R-2) under saline conditions: 50 mM (low salinity, LS), and 100 mM (high salinity, HS). Seeds were germinated with 1.5 (SW1) and 3% (SW2) seaweed powder mixed with saline soil. Root and shoot length progressively decreased with increasing salinity level compared to control. Treatment 2 (SW1) and treatment 4 of R-1 variety had the highest germination rate by 95%. R-2 variety showed increased shoot and root fresh weight for treatment 4 (LS) and treatment 8 (HS + SW1), while treatment 7 (LS + SW2) of R-2 variety showed the highest shoot dry weight. Treatment 2 (SW1) of R-1 variety showed an increase in plant total weight compared to R-1 variety. Carbohydrate and protein content were higher in treatment 4 (LS) and 9 (HS + SW2) of R-1 variety. Phenol and flavonoid content were increased in treatment 8 (HS + SW1) and 2 (SW1) of R-2 variety compare to untreated controls. Marine algae-based bio-stimulant could effectively improve Radish growth due to optimum physiological and biochemical alteration under saline conditions. Our results indicate that radish varieties could produce sustainable biomass by using algal bio-stimulant on saline soils and avoiding competition with conventional agriculture.