|
|
||||||||
USDA-ARS Natl. Soil Dynamics Lab., P.O. Box 3439, Auburn, AL 36831-3439
Dep. of Agronomy and Soils, Auburn Univ., Auburn University, AL 36849-5412.
* Corresponding author (Email: wreeves{at}ag.auburn.edu).
Deep placement of K fertilizer may alleviate late-season K deficiency of cotton (Gossypium hirsutum L.) on soils adequate in surface soil K but low in subsoil K. This 2-yr study in Alabama evaluated effects of deep tillage (in-row subsoiling) and K fertilizer placement on yield, leaf K deficiency, soil water depletion, and stomatal conductance of cotton grown on a soil with a root-restricting hardpan. The Norfolk sandy loam (fine-loamy, siliceous, thermic Typic Kandiudults) soil tested medium for K in the top 15 cm and low at greater depths. Treatments were: (i) no K, no subsoiling; (ii) no K, subsoiled; (iii) surface application (84 kg K ha–1), no subsoiling; (iv) surface application, subsoiled; and (v) deep placement in the subsoiled channel. Surface application without subsoiling resulted in the greatest soil water content (0- to 80-cm depth); deep placement, the lowest. Stomatal conductance was highest with no-K, no subsoiling and lowest with K (surface or deep), subsoiled. There was no evidence of K or drought stress-induced stomatal closure, and stomatal closure was not related to severity of leaf K deficiency. All three K treatments increased leaf K concentration at early bloom. Subsoiling without K fertilizer increased plant size and severity of leaf K deficiency; with surface K, subsoiling more than doubled total leaf area but did not affect leaf K deficiency. Within subsoiled treatments, leaf K deficiency was more severe with deep placement of K than with surface application. Subsoiling, especially with K fertilizer, maximized seed cotton yield in both years (avg. 3261 kg ha–1) but reduced stomatal conductance. Stomatal closure and premature leaf senescence are not the likely mechanism for late-season leaf K-deficiency in cotton. Although subsoiling was necessary to maximize cotton yields on this Coastal Plain soil with a root-restricting hardpan, deep placement of K fertilizer was not superior to surface application.
Received for publication July 5, 1994.
This article has been cited by other articles:
![]() |
G. Siri-Prieto, D. W. Reeves, and R. L. Raper Tillage Requirements for Integrating Winter-Annual Grazing in Cotton Production: Plant Water Status and Productivity Soil Sci. Soc. Am. J., January 1, 2007; 71(1): 197 - 205. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. H. Schomberg, R. G. McDaniel, E. Mallard, D. M. Endale, D. S. Fisher, and M. L. Cabrera Conservation Tillage and Cover Crop Influences on Cotton Production on a Southeastern U.S. Coastal Plain Soil Agron. J., August 3, 2006; 98(5): 1247 - 1256. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. S. Balkcom, D. W. Reeves, J. N. Shaw, C. H. Burmester, and L. M. Curtis Cotton Yield and Fiber Quality from Irrigated Tillage Systems in the Tennessee Valley Agron. J., April 11, 2006; 98(3): 596 - 602. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. B. Schwab, D. W. Reeves, C. H. Burmester, and R. L. Raper Conservation Tillage Systems for Cotton in the Tennessee Valley Soil Sci. Soc. Am. J., March 1, 2002; 66(2): 569 - 577. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| The SCI Journals | Crop Science | Vadose Zone Journal | |||
| Journal of Natural Resources and Life Sciences Education |
Soil Science Society of America Journal | ||||
| Journal of Plant Registrations | Journal of Environmental Quality |
The Plant Genome | |||