The effect of agricultural sulfur levels and application dates on the NPK rate and some growth characteristics during the growth stages of the yellow corn plant, Zea mays.

Abstract

      A field experiment was carried out during the summer season 2021-2022 in the fields of the College of Agriculture - Wasit University, with the aim of knowing the role of adding agricultural sulfur at different levels and timings in the degree of interaction of the soil and micronutrients (iron, manganese, zinc, copper) and its effect on the growth of the yellow corn crop, Zea mays. The study included two addition dates: 30 days before planting, and the second date (15 days after the first addition date), and at four levels: 500, 1000, 1500, 2000 kg/hectare-1. The experiment was implemented in a randomized complete block design (R.C.B.D.) with three replications for all experimental treatments, which were distributed randomly among the treatments, so that the total number of units became 27 experimental units. The results showed the following:

The results of the sulfur addition treatment at a level of 2000 kg.ha-1 for the first date (30 days before planting) showed the highest concentration of nitrogen, which reached 1.85% compared to the comparison treatment, which gave the lowest rate of nitrogen in the plant, which amounted to 0.97%, and phosphorus, which amounted to 0.29% in comparison. With the comparison treatment, in which the concentration of phosphorus reached 0.06%, and potassium in which it reached 1.18%, compared to the comparison treatment, which gave the lowest rate of potassium in the plant, as it reached 0.66% in the yellow corn plant at the flowering stage, while the rates of the same treatment were in the harvest stage, where it recorded an average Nitrogen, which amounted to 1.43% compared to the control treatment, which gave the lowest rate of nitrogen in the plant, which amounted to 0.94%, and phosphorus, which amounted to 0.27%, compared to the comparison treatment, in which the phosphorus concentration reached 0.06%, and potassium, which amounted to 1.02%, compared to the comparison treatment, which gave the lowest rate. For potassium in the plant, it reached 0.76%. The results showed that increasing levels of sulfur fertilizer in the soil led to an increase in some growth characteristics and yield, and that the highest rate of leaf area in yellow corn plants was achieved in the sulfur addition treatment at the level of 2000 kg hectare-1 in the experiment, where it reached 6270.48 cm2 compared to the treatment without Adding 5513.6 cm2, the treatment also achieved the highest rate of plant height, which amounted to 200.17 cm compared to the comparison level, in which the average height reached 188.27 cm, and the highest rate of chlorophyll content in leaves, which amounted to 38.9 SPAD compared to the comparison treatment, which amounted to 28.47 SPAD. The same treatment achieved the highest rate of stem diameter, which reached It reached 2.27 cm compared to the comparison treatment, which amounted to 1.78 cm.