Project Summary Outline
Project title:
Improving Fertilizer Recommendations for Corn - The Nebraska Soil Fertility Project (NSFP)
A. Dobermann, J. Blumenthal, R. Ferguson, C. Shapiro, D.
Tarkalson, C. Wortmann, D. Walters
Duration: 2002-2004
Funding: Nebraska
Department of Agriculture
Project
management:
Although UN-L soil fertility staff have the overall scientific responsibility for conducting this research, an external technical advisory committee (TAC) has been established to represent public and private sector stakeholders involved and help guide both the research and the development of improved recommendations.
Contact:
Achim
Dobermann
University
of Nebraska-Lincoln
Department
of Agronomy and Horticulture
Lincoln,
68583-0915
(phone:
402-472-1501)
Project
description:
Currently used soil testing and fertilizer management recommendations are the result of many years of research and field verification conducted in Nebraska and other Midwestern states. However, many recommendations and Best Management Practices (BMP) in use today were developed decades ago. It is reasonable to question whether these recommendations are applicable with precision agriculture technology, particularly at yield levels that exceed those achieved during the original calibration research.
The goal of this project is to develop improved nutrient management
recommendations for corn in Nebraska, including new software tools for
fertilizer management. Our focus is on improving the UN-L recommendations, but
the field research conducted will also provide updated data to potentially
improve fertilizer recommendations used by private soil testing laboratories or
fertilizer dealers and agronomy service companies. Over the longer term, this
should lead to more uniform, validated recommendations offered to farmers in
Nebraska. Specific objectives are:
1. To establish a geo-referenced database on soil
fertility and crop response to nutrients.
2. To verify or revise existing N, P, and K fertilizer
recommendations for corn in Nebraska at current and future yield levels and
cropping technologies.
3.
To assess the
potential for an alternative approach for management of N, P, and K based on
quantitative relationships between nutrient supply, crop nutrient demand,
yield, and economics of fertilizer use, including the interactions between
nutrients.
4. To fine-tune fertilizer recommendations for corn to
major agroecological zones and specific crop management practices in Nebraska.
5. To develop software tools for nutrient management.
Detailed nutrient trials are being conducted to gather data sets that cover a wide range of soil nutrient supply and yield response by (a) using sites along an agroecological gradient, (b) measuring the spatial variation within each field, and (c) applying combinations of nutrient treatments that, together with the underlying variation in soil nutrients, will create a wide range of yield response within each site. In this project we attempt to create a wide range in yield (e.g., from 100 to >250 bu/acre in corn) by using several levels of NPK treatments. Data collected in the field will be used to verify and possibly modify existing fertilizer recommendation algorithms to more accurately reflect the range of soils and climatic conditions present across the state. This includes information to improve both sufficiency and buildup-maintenance approaches. Additionally, the data will be used to evaluate the potential for an alternative NPK management approach, which is based on quantitative modeling of yield potential and crop nutrient requirements.
Key
results:
Publications: