The effect of mixed fertilizers containing little or no calcium or sulfur on seed cotton yields

Author

William Thomas Pettigrew

Date of Award

8-1982

Degree Type

Thesis

Degree Name

Master of Science

Major

Plant, Soil and Environmental Sciences

Major Professor

W. L. Parks

Committee Members

G. M. Lessman, L. N. Skold

Abstract

During the 1980 and 1981 crop seasons, two experiments were conducted on a Coring silt loam, a typic Fragiudalf, at Ames Plantation and a Collins silt loam, an aquic Udifluvent, at the Milan Experiment Station to determine the effect of fertilizers containing little or no calcium or sulfur on cotton yield and on the cotton leaf levels of sulfur, calcium, nitrogen, phosphorus, potassium, and magnesium. The only differences between the two experiments, which were adjacent to each other, were that one experiment utilized mechanical weed control while the other experiment utilized chemical weed control. Both experiments had six fertilizer treatments replicated four times at Ames and six times at Milan. Each experimental plot consisted of four 102 cm rows 9.15 m long. The fertilizer treatments used potassium sulfate and potassium chloride as potassium sources. Ordinary superphosphate and diamonnium phosphorus were the phosphorus sources. The phosphorus was applied in rates of 29 and 59 kg of phosphorus/ha. Varying the potassium source and the phosphorus source and level resulted in different amounts of sulfur and calcium applied. The youngest mature leaves were sampled at initial bloom stage from the two inner rows of the four row plots. Yield data were obtained by harvesting the two inside rows.

None of the treatments had a significant effect on the seed cotton yields. Comparisons between the seed cotton yields of the experiments without herbicide and with herbicide showed that the yields without herbicide were greater than the yields with herbicide. This effect occurred both years at Ames and one year at Milan.

The cotton leaves when analyzed for sulfur, calcium, nitrogen, phosphorus, potassium, and magnesium showed many significant differences due to the different fertilizer treatments.

Recommended Citation

Pettigrew, William Thomas, "The effect of mixed fertilizers containing little or no calcium or sulfur on seed cotton yields. " Master's Thesis, University of Tennessee, 1982.
https://trace.tennessee.edu/utk_gradthes/7608