EFFECT OF ORGANIC AND INORGANIC FERTILIZERS ON THE GROWTH AND VEGETATIVE YIELD OF GREEN AMARANTH (Amaranthus viridis)

Abstract

A field experiment was carried out at the Research Field, Department of Soil Science, Hajee Mohammad Danesh Science and Technology University, Dinajpur, during the period from November 2023 to February 2024 in Rabi season to evaluate the efficacy of different organic and inorganic fertilizers on the growth and vegetative yield of green amaranth. The experiment was laid out in Randomized Complete Block Design (RCBD) having six treatments with three replications. The treatments were as follows; T1 = Control, T2 = 100% NPK, T3 = 100% (compost+cowdung), T4 = 25% NPK + 75%(compost+cowdung), T5 = 50% NPK+50%(compost+cowdung),T6 =75% NPK + 25%(compost+cowdung). The experimental soil belongs to the Old Himalayan Piedmont Plain (AEZ-1). The soil was sandy loam in texture having pH 5.60, organic matter content 0.82%, total N 0.080%, available P 3.30 ppm, exchangeable K 0.52meq 100 g-1 soil and available S 7.53ppm. The tallest plant height (6.97, 30.73, and 38.80 cm at 15, 30, 45 DAS respectively) was found in the treatment T6 and the shortest plant height (5.76, 12.50, and 15.80 cm at 15, 30, and 45 DAS, respectively) was observed in T1 (control). The maximum number of leaves (5.60, 8.70, 10.70 at 15, 30, and 45 during final harvest, respectively) was recorded in the treatment T5 whereas the minimum number of leaves (5.10, 7.30, 9.30 at 15, 30, 45 during final harvest, respectively) was found in the T1 (control). The treatment T5 produced the highest both fresh and dry shoot weight (6.23 and 3.78 t ha-1 respectively) but the lowest fresh and dry shoot weight (1.16 and 0.52 t ha-1 respectively) was obtained from the control treatment (T1). The maximum fresh and dry root weight (2.29 and 1.28 t ha-1, respectively) was found in T5 and tallest root length (7.89 cm) was recorded from the treatment T6 and the minimum both fresh and dry root weight (0.42 and 0.19 t ha-1, respectively) and smallest root length (6.20 cm) was observed in the T1 (control).Application of organic and inorganic fertilizers resulted in a considerable influence on the properties of the post-harvest soils such as pH, organic matter content, total N, available P, exchangeable K and available S. In post-harvest soil, the combined application of NPK and compost gave positive results. It also increased soil fertility status. The highest percentage of total N of and available S (0.112 % and 18.05 ppm, respectively) were found in T6 treatment and lowest percentage of N and available S (0.056 % and 5.73 ppm, respectively) were in T1 treatment. The highest available P (9.772 ppm) and exchangeable K (0.160 meq/100 g soil) were found in both cases at T5 and the lowest available P and K (3.063 ppm and 0.050 meq/100 g soil, respectively) was in T1 (control) treatment. The highest pH (7.20) was observed for T3 treatment while T1 showed the lowest value (5.60). In post-harvest soil electrical conductivity was statistically different for different treatments. The soil electrical conductivity percentage was highest(0.328 ms) in T2 which was statistically similar with T3 and the soil electrical conductivity percentage was lowest(0.050ms) in T1 . The soil organic matter percentage was highest (1.400 %) in T3 treatment which was statistically identical to T4 and T5 . The lowest organic matter content (0.887 %) was found in T1 treatment. Finally, it can be concluded from the present study that the application of organic manures with the recommended doses of inorganic fertilizers showed better performance in respect of vegetative growth of green amaranth and also increased the fertility status in soil. Moreover, 50% NPK + 50% compost and cowdung (T5) gave better performance than other combinations in all aspects. So, compost with inorganic fertilizers will be profitable for green amaranth cultivation.