Sulphur (S) is an essential element for plant and animal nutrition, but widespread deficiencies of S occur world wide. Current recommendations for nitrogen (N):S ratios are 15 to 18:1 and 10 to 12:1 for plant and animal nutrition, respectively; but recent information suggests these may not predict animal response. Sorghum is an important crop, particularly in drier climatic regions but little is known concerning S-nutrition for sorghum growth or utilization of S-fertilized forages. Sorghum "Pioneer 947" was grown on a Lucy loamy sand (loamy, siliceous, thermic Arenic Kandiudult) in King William County, VA, with and without S fertilization (0 vs. 138 kg S ha⁻¹ as ammonium sulphate) in a randomized block design with four replications. Sulphur fertilization decreased (P < 0.05) soil pH and increased soil S in the 0 to 25 cm (P < 0.08) and 25 to 50 cm (P < 0.05) soil layers. An increase in Mehlich-I extractable soil P, Mn (P < 0.05) and soil N0₃-N (P < 0.06) at surface 25 cm layer occurred with S-fertilization. At harvest, S-fertilization increased (P < 0.05) S and water soluble carbohydrates and decreased (P < 0.05) N:S ratio and P concentration in whole plants. Sorghum leaves were higher (P < 0.05) in N, S, Ca, Mn and Cu in S fertilized compared to non-S fertilized sorghum. Sulphur fertilization decreased (P < 0.05) concentration of hydrocyanic acid (HCN) in the upper three leaves. A greenhouse experiment was conducted with the Lucy soil and 'Pioneer 947' sorghum to further investigate effects of fertilization (0, 70, and 140 kg S ha ⁻¹) as ammonium sulphate in a completely randomized design with five replications. Sulphur application decreased soil pH, and extractable soil K linearly (P < 0.01), and increased extractable soil S linearly (P < 0.01). / Ph. D.
| Identifer | oai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/39958 |
| Date | 19 October 2005 |
| Creators | Ahmad, Muhammad Rashid |
| Contributors | Crop and Soil Environmental Sciences, Allen, Vivien G., Fontenot, Joseph P., Reneau, Raymond B. Jr., Parrish, David J., Hawkins, George W. |
| Publisher | Virginia Tech |
| Source Sets | Virginia Tech Theses and Dissertation |
| Language | English |
| Detected Language | English |
| Type | Dissertation, Text |
| Format | xii, 149 leaves, BTD, application/pdf, application/pdf |
| Rights | In Copyright, http://rightsstatements.org/vocab/InC/1.0/ |
| Relation | OCLC# 24448287, LD5655.V856_1991.A442.pdf |
Page generated in 0.2169 seconds