Mid-Season Recovery from Nitrogen Stress in Winter Wheat |
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Authors: | K B Morris K L Martin K W Freeman R K Teal K Girma D B Arnall |
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Institution: | Department of Plant and Soil Sciences , Oklahoma State University , Stillwater, OK, USA |
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Abstract: | ABSTRACT Although spring-applied nitrogen (N) has been shown to be most efficient, the technique of delaying all N applications until mid-season, and the resultant effect on maximum yields, has not been thoroughly evaluated. This experiment was conducted to determine if potential yield reductions from early-season N stress can be corrected using in-season N applications. Data from three experimental sites and two growing seasons (six site-year combinations) were used to evaluate three preplant N rates (0, 45, and 90 kg ha?1) and a range of in-season topdress N rates. Topdress N amounts were determined using a GreenSeeker hand-held sensor and an algorithm developed at Oklahoma State University. Even when early-season N stress was present (0-N preplant), N-applied topdress at Feekes 5 resulted in maximum or near-maximum yields in four of six site-year combinations when compared with other treatments receiving both preplant and topdress N. |
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Keywords: | N stress mid-season N N recovery |
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