Effect of organic root plus (biostimulant) on the growth, nutrient content and yield of amaranthus

Abstract

The effectiveness of organic root plus (biostimulant) was compared with conventional fertilizer on the growth and yield of amaranthus in a glass house study. The treatments consisted of control, full rate each of biostimulant and fertilizer, and combination of fertilizer with biostimulant at full and half rates. The urea, single super-phosphate and muriate of potash were applied at 100 kg N, 60 kg P2O5 and 30 kg K/ha (fertilizer full rate) respectively, while biostimulant was applied at the rate of 40 litres/ha. The results obtained showed that the use of organic biostimulant alone was not as effective as that of fertilizer alone in most of the parameters considered. The conventional fertilizer had percentages increases of 38 and 82, 19 and 73, 35 and 3, in number of leaves, plant height and leaf area in the first cycle and regeneration, respectively, over the sole use of biostimulant. Complimentary application of biostimulant with mineral fertilizer promoted the vegetative growth, nutrient  composition, root development and yield of amaranthus. When full rate of biostimulant was combined with full rate of mineral fertilizers, the number of leaves, plant height, leaf area and shoot yield were increased 15 and 11%, 27 and 14%, 7 and 5%, 15 and 15%, in the first cycle and at regeneration, respectively, over the mineral fertilizer. The combinations of the two materials at various ratios were also effective.