Polysaccharides combined to copper and magnesium improve tomato growth, yield, anti-oxidant and plant defense enzymes

The search for sustainable technologies to increase yield are fundamental for a modern agriculture. Polymers of biological origin (e.g., polysaccharides) have been studied for their potential use in agriculture. These substances present a great possibility of agricultural uses allowing their combination with nutrients to improve the uptake by plants. In this regard, the association of copper and magnesium to polysaccharides was investigated in the tomato cultivation in pots conducted with fertigation under protected environment. Two experiments were conducted: (i) foliar application of polysaccharides and their association with copper and magnesium in the initial growth of tomato plants; and (ii) tomato yield with foliar application of polysaccharides and their association with copper and magnesium. Growth, leaf nutrient content, enzymes and biochemical variables, fruit yield and leaf disease severity index were analyzed. The foliar sprays with polysaccharides in the combination with copper and magnesium was efficient to promote plant growth and yield. It also improved the concentration of antioxidant enzymes and the β,1,3 glucanase enzyme, while reducing the severity of powdery mildew in tomato leaves.