Fertilizer and Ag Lime Grants
Title: Refining Soil Test Recommendations for Wheat
Principal Investigators: Peter Scharf, John Lory, Manjula
Nathan, and Anne McKendry
Agronomy Department, University of Missouri
- Test the performance of current University of Missouri soil test
recommendations for predicting wheat yield response to P, K, and S
in a statewide network of experiments.
- Explore the possibility that subsoil test values, soil type, or
soil region could be used to improve our fertilizer recommendations
and make them more site-specific.
- Experiments will be added to an existing statewide network of 7
wheat variety trials conducted by the University of Missouri.
Experiments will be adjacent to but separate from variety trials. A
research specialist will arrange with cooperating producers to
conspicuously mark the experimental area where P and K fertilizers
will not be applied. Variety testing personnel will plant,
fertilize, and harvest the experiments.
- Two experiments will be located in northern Missouri, 1 in
central Missouri, 2 in southwest Missouri, and 2 in southeast
- P, K, and S fertilizers will be hand-applied to separate plots
at rates of 80 lb P2O5, 80 lb K2O, and 20 lb S/acre. These rates
should be high enough to produce full yield response. Yields of
fertilized plots will be compared to yields of unfertilized check
- Six replications will be used.
- Soil samples will be taken at depths of 0 to 6, 6 to 12, 12 to
24, and 24 to 36 inches in each experiment and analyzed for pH, P,
K, and S.
- One well-adapted variety will be used at each location.
- Yield response data will be analyzed to assess the performance
of current University of Missouri soil test recommendations and to
look for ways to improve our recommendations, possibly including
subsoil test values, soil type, or soil region.
- All experiments will be in rotation.
2000-2001 EXPERIMENTAL SITES
Portageville||Pemiscot||Tiptonville Silt Loam|
Trenton||Grundy||Grundy Silt Loam|
Novelty||Knox||Kilwinning Silt Loam|
Columbia||Boone||Mexico Silt Loam|
Mt. Vernon||Lawrence||Gerald Silt Loam|
Accomplishments for 2000:
- Field activities planned for this fall have been completed.
- Fertility experiments have been planted alongside an existing
statewide network of 7 wheat variety trials conducted by the
University of Missouri. Two of the seven locations will not have
fertility trials - one due to the wishes of the cooperating producer,
and another that was fertilized with P and K in the first week of
September before we contacted the cooperating producer.
- Arrangements were made to have no P and K fertilizer applied to
the remaining five experimental areas this fall.
- P, K, and S treatments have been applied.
- Deep soil samples have been taken and analyzed.
- Experiments will be harvested in late June or early July 2001.