Document Type

Thesis - University Access Only

Award Date


Degree Name

Master of Science (MS)

Department / School



Phosphorus (P) is an important nutrient for all plants. Farmers around the world apply it as a fertilizer to agricultural crops. This study looked at the effects P fertilizer has on grain yield and height of soybean, and yield, height, and test weight of oat and wheat in a no-till system. Mycorrhizal colonization in oat and wheat roots was also measured. Phosphorus concentration of the above ground portion was measured in oat in the first year of the experiment, and in wheat in the second year. Treatments used were: Prates (0, 20, 40, and 80 lbs/a), either banded or broadcast. The residual effect of the P treatments was compared to a current year's application of P. Yield consistently increased with increasing rates of P for all three crops. Banded P significantly increased yields of the three crops over broadcast P. No significant difference was found between residual and current year's application of Pin oat and soybean yields, but wheat yields were significantly increased by a current year's application of P over residual P. Height of the three crops increased as the rate of P increased. Plants receiving the banded P treatment were generally taller than those receiving the broadcast P treatment. Year of application had no significant effect on height of any of the crops. Test weight of the oat and wheat was increased by increasing rates of P, but the increase was less than one pound per bushel. Placement and year of application had no effect on test weight. No interaction was found between mycorrhizal colonization and any of the treatments in either the oat or the wheat roots. Phosphorus concentration was increased in both the oat and wheat as the rate of P increased. In the oat, plants receiving broadcast P had a higher P concentration than those receiving banded P. Placement of the P had no effect on P concentration of the wheat. A current year's application of P significantly increased P concentration over residual P in the wheat.

Library of Congress Subject Headings

Phosphorus in agriculture
Oats -- Fertilizers
Wheat -- Fertilizers
Soybean -- Fertilizers



Number of Pages



South Dakota State University