Proceedings
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| Filter results4 paper(s) found. |
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1. Crop Yield Relationship to Remote Sensing Data Using Intensified Weighted Nonlinear Regression ModelsYield prediction is important for making in-season agronomic input decisions as well as for greater logistical decisions. In predicting the crop yield based on ground-based active optical sensing data, the ordinary statistical unweighted linear or nonlinear regression models are the most popular choices. However, these unweighted models may not be accurate enough for practical use because they are based on the assumption that each data point for regression is obtained with equal precision and that... |
2. Correlation and Calibration of the Mehlich 3 P Soil Test for Soybeans in KansasKansas currently uses the Mehlich 3 soil test for P, with a general P soil test (STP) critical level for all crops of 20 ppm (colorimetric). This critical level was established based on field research primarily with wheat in 2003. A review of the limited research data available from Kansas suggests that soybeans may not require as high a STP level as wheat for optimum yield. Therefore the objective of this study is to determine what the appropriate critical STP level is for optimum soybean production... |
3. Soybean Whole Plant, and Trifoliate Phosphorus Concentration Relationships to Yield and Phosphorus Removal RatesPlant tissue analysis is becoming a more popular tool to diagnosis nutrient deficiencies. Whole plant samples may be taken early ( corrections. Leaf samples taken just before grain fill may be used to diagnose problem spots in a field. Benton Jones Jr. et al. (1991) reports that the phosphorus (P) sufficiency range for upper most developed trifoliates is between 0.26 and 0.50 percent P. There is no published data on whole plant P sufficiency ranges from V4 to V6. Nutrient grain analysis is valuable... |
4. Nitrogen Recalibration for Spring Wheat and Durum in North DakotaNorth Dakota will begin using new fertilizer r ecommendations beginning Dec. 1, 2009. Previous recommendations required a yield guess by growers with no rega rd to economics of nitrogen application. The new recommendations recogni ze different N response curves with yield and grain protein within three state agri-climatology zones. The reco mmendations use the "return to N" method, which vary the N recommendation based on crop price and N costs. The resulting rate is adjusted based on... D. Franzen, G. Endres, J. Lukach, R. Ashley, J. Staricka, K. Mckay |