| dc.description.abstract | The objective of this research was to determine the effects of calcium (Ca) additions on nitrogen (N) uptake by corn (Zea mays L.). The purpose for adding the calcium was to determine if it would increase the nitrogen uptake by the corn, thus increasing nitrogen use efficiency. Calcium chloride and ammonium (NH₄⁺) chloride fertilizers were used. Darco loamy fine sand (acid soil) and Norwood silt loam (calcareous soil) were used to determine the effects of calcium on on corn growth in different types of soil.
Nitrogen is the most limiting nutrient for plant growth. Losses of applied nitrogen are often great, with an average use efficiency of only 50%. This research was conducted to determine the effect of added calcium on plant growth and nitrogen uptake on acid and calcareous soils.
Plant height at four and nine weeks was influenced by soil type. The Darco soil at four weeks produced plants with a greater height than the Norwood soil. At nine weeks, however, the plants on the Norwood were greater in height. This change was influenced by the Mg, P, and K that was abundant 10 the Norwood and not the Darco. As the nitrogen rate was increased at both four and nine weeks, plant height increased. The only exception at four weeks was that no difference was observed between 100 and 200 lbs N/ac.
The calcium rate of 150 lbs/ac at four weeks had a significant impact on height on both soils. Corn on the Darco soil exhibited an increase in height, while plants on the Norwood soil declined in height. At nine weeks, 150 lbs Ca/ac on the Darco soil produced a significant increase 10 plant height. No effect was noted with corn on the Norwood soil at nine weeks.
Leaf area increased as the amount of nitrogen applied increased. Calcium, however, had no influence on total leaf area.
The influences of calcium and nitrogen on plant dry weight were similar to those observed on leaf area. Soil type did have an effect on plant dry weight, with the Norwood soil producing plants with greater dry weight.
The major factor that impacted the concentration of nitrogen in the plant was the rate of nitrogen. As the N rate increased, the N concentration increased. Calcium, however, did influence nitrogen content on the Darco soil at the 7% probability level.
Calcium applied at 150 lbs/ac significantly increased the calcium concentration of plants on the Darco soil. However, calcium did not influence Ca concentration in the corn on the Norwood soil.
The major impact on total nitrogen and calcium uptake was the amount of nitrogen applied. As the nitrogen rate was increased on both the Darco and Norwood soils, the total N and Ca uptake by the corn was increased. The rate of 150 lbs Ca/ac on the Darco soil did enhance the uptake of calcium. Other calcium rates resulted on producing no significant difference in N and Ca uptake with the Darco soil. Calcium rate had no significant impact on total Nand Ca uptake on the Norwood soil.
Factors measured were weekly plant height, leaf area, root growth, percent nitrogen and calcium, and total uptake of nitrogen and calcium by corn. Calcium and nitrogen resulted in having similar influence on all of the factors measured. Nitrogen results of the factors measured were also similar. Calcium additions did not increase the nitrogen uptake by the corn on either soil. Nitrogen, however, was determined to be the major determinant of plant growth in this study. The level of nitrogen increased both the nitrogen and calcium content and uptake by corn. | en |
