Proceedings
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| Filter results7 paper(s) found. |
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1. Nitrogen Fertilizer on Soybeans: Are We Making Progress?The recent drop in the price of soybeans has dampened enthusiasm for applying inputs of uncertain value to crops, but application of fertilizer N during the season is often reported by soybean yield contest winners as a way to increase yields, and some producers have adopted this as a practice. As soybean yields have increased, the amount of N required by the crop has increased. Soybean seed with 36 percent protein is about 5.75% N, and a bushel of soybean grain contains about 3 lb.... E. Nafziger, J. Vonk |
2. Alternative Approaches to Making Fertilizer RecommendationsThe objective of this research project was to evaluate, both agronomically and economically. some common altcrnative methods of making fertilizer recornmcndations for corn, soybeans, and soft-red winter wheat used in Indiana. Over a period of six years ( 1992- 1997) the effect of seven alternative fertilizer recommendation philosophies on soil test levels, crop yields, plant tissue analysis, and fertilizer additions were measured in an attempt to determine differences in performance between these... |
3. Basic Concepts of Soil Acidity and LimingMost midwestern soils require periodic applications of aglitne or other liming materials for optimum crop production. Liming has several beneficial effects: I ) it reduces harmhl or potentially tosic conditions which can develop in acid soils; 2) it increases the availability of some of nutrients: 3) it replaces the supply of calcium and magnesium essential for plant growth which is depleted as soils become acid; 4) it ensures favorable conditions for the activity of certain herbicides; and 5) it... |
4. Providing Flexibility in P and K RecommendationsHistorically, land grant Universities have generally provided a single rate recommendation for nutrients such as phosphorus (P) and potassium (K). Depending on the particular University in question, these nutrient rate recommendations are generally based on two widely recognized approaches to managing soil and fertilizer P and K - the nutrient sufficiency approach and the build-maintenance approach. The goal of a nutrient sufficiency based soil fertility program is to apply just enough P andior K... |
5. Evaluation of Novel Soybean Inputs to Enhance YieldThe U.S. Average soybean yield was 43.5 bushes/acre in 2010 (www.nass.usda.gov), with reports of much higher yields in some areas. With large yield differences among years and locations, as well as some high-profile marketing and publicity campaigns promoting 'high yield' management, producers are interested in any inputs or management practices that might improve yields. High soybean prices at present and interest in finding ways to increase yield have led to emergence of a number of new products,... |
6. Recoverable Yield: A New Component for Improving Algorithms Used For Sensor Based Nitrogen Management In WheatIncreased interest in N management over the past decade has stimulated interest in using optical sensors to predict N needs in a number of crops. Many universities have created N recommendation algorithms for winter wheat, with slightly differing approaches. While many university algorithms operate under the assumption that 100% of the yield potential difference between the N rich strip and the farmer practice can be recovered, we believe that this will not always be possible. The objective of this... |
7. Nitrogen Fertilizer For SoybeanConcern about soybean’s ability to provide energy to fix adequate N while still producing high yields has led to renewed interest in in-season use of N fertilizer. We conducted a series of fertilizer N timing experiments in Illinois, in different soil types with a range of yield potential. There were few responses to N in silt loam soils, with unfertilized check yields ranging from 4,108 to 6,125 kg/ha, though applying the same N increment four times increased yield significantly... J. Vonk, E. Nafziger |