Evaluation of the Accuracy of a Wheat Stem Nitrate Test in Predicting Nitrogen Requirements of Irrigated Durum Wheat

Persistent Link:
http://hdl.handle.net/10150/200815
Title:
Evaluation of the Accuracy of a Wheat Stem Nitrate Test in Predicting Nitrogen Requirements of Irrigated Durum Wheat
Author:
Doerge, T.; Knowles, T.; Ottman, M.
Issue Date:
Sep-1988
Publisher:
College of Agriculture, University of Arizona (Tucson, AZ)
Journal:
Forage and Grain: A College of Agriculture Report
Abstract:
The procedure currently recommended by the University of Arizona for predicting the nitrogen (N) requirements of durum wheat has proven to be quite accurate at sites where grain yields exceeded 5,400 lbs/acre. However, the method slightly overestimated N needs when the yield possibility was below that level. Additional information on the relationships between N rates, stem NO₃⁻N levels and grain yields are needed for the wide range of agronomic conditions found in Arizona. Three N fertility trials were conducted at the Maricopa Agricultural Center to: 1) document the accuracy of the currently recommended soil + stem NO₃⁻N testing procedure in predicting the N needs of durum wheat on soils of varying residual N content and grain yield potentials; and 2) to evaluate the use of the current stem testing procedure on two durum varieties 'Aldura' and 'Westbred -881. The University of Arizona procedure was found to accurately predict the minimum amount of N required for optimum production of durum wheat on two sites where yield potentials were 5,400 and 4300 lbs. grain /A, but it slightly overpredicted N rates on two sites with maximum yield levels of 5,400 lbs /a. 'Aldura' consistently out yielded 'Westbred -881' by about 12 % but 'Aldura' also averaged 0.78 %lower in grain protein content. Little statistical or practical differences were observed in the quantities of NO₃⁻N contained in the stem tissue of these two varieties, which should simplify the interpretation of stem NO₃⁻N values for various wheat cultivars. The currently recommended procedure for predicting optimum N rates in durum wheat production has proven to be accurate when yield levels exceed 5,400 lbs. grain /A. A slight modification of the procedure may be needed to more closely predict N requirements on lower yielding sites.
Keywords:
Agriculture -- Arizona; Grain -- Arizona; Forage plants -- Arizona; Barley -- Arizona; Oats -- Arizona; Wheat -- Arizona; Barley -- Fertility; Oats -- Fertility; Wheat -- Fertility
Series/Report no.:
Series P-74; 370074

Full metadata record

DC FieldValue Language
dc.titleEvaluation of the Accuracy of a Wheat Stem Nitrate Test in Predicting Nitrogen Requirements of Irrigated Durum Wheaten_US
dc.contributor.authorDoerge, T.en_US
dc.contributor.authorKnowles, T.en_US
dc.contributor.authorOttman, M.en_US
dc.date.issued1988-09-
dc.publisherCollege of Agriculture, University of Arizona (Tucson, AZ)en_US
dc.identifier.journalForage and Grain: A College of Agriculture Reporten_US
dc.description.abstractThe procedure currently recommended by the University of Arizona for predicting the nitrogen (N) requirements of durum wheat has proven to be quite accurate at sites where grain yields exceeded 5,400 lbs/acre. However, the method slightly overestimated N needs when the yield possibility was below that level. Additional information on the relationships between N rates, stem NO₃⁻N levels and grain yields are needed for the wide range of agronomic conditions found in Arizona. Three N fertility trials were conducted at the Maricopa Agricultural Center to: 1) document the accuracy of the currently recommended soil + stem NO₃⁻N testing procedure in predicting the N needs of durum wheat on soils of varying residual N content and grain yield potentials; and 2) to evaluate the use of the current stem testing procedure on two durum varieties 'Aldura' and 'Westbred -881. The University of Arizona procedure was found to accurately predict the minimum amount of N required for optimum production of durum wheat on two sites where yield potentials were 5,400 and 4300 lbs. grain /A, but it slightly overpredicted N rates on two sites with maximum yield levels of 5,400 lbs /a. 'Aldura' consistently out yielded 'Westbred -881' by about 12 % but 'Aldura' also averaged 0.78 %lower in grain protein content. Little statistical or practical differences were observed in the quantities of NO₃⁻N contained in the stem tissue of these two varieties, which should simplify the interpretation of stem NO₃⁻N values for various wheat cultivars. The currently recommended procedure for predicting optimum N rates in durum wheat production has proven to be accurate when yield levels exceed 5,400 lbs. grain /A. A slight modification of the procedure may be needed to more closely predict N requirements on lower yielding sites.en_US
dc.subjectAgriculture -- Arizonaen_US
dc.subjectGrain -- Arizonaen_US
dc.subjectForage plants -- Arizonaen_US
dc.subjectBarley -- Arizonaen_US
dc.subjectOats -- Arizonaen_US
dc.subjectWheat -- Arizonaen_US
dc.subjectBarley -- Fertilityen_US
dc.subjectOats -- Fertilityen_US
dc.subjectWheat -- Fertilityen_US
dc.identifier.urihttp://hdl.handle.net/10150/200815-
dc.relation.ispartofseriesSeries P-74en_US
dc.relation.ispartofseries370074en_US
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