|Fausey, Norman - Norm|
Submitted to: Crop Science
Publication Type: Peer reviewed journal
Publication Acceptance Date: 6/23/2000
Publication Date: N/A
Citation: Interpretive Summary: Flooding reduces soybean growth and grain yield in many areas of the U.S. and the world. We sampled the soil and plants in flooded areas within production fields to explore the relationships between these properties and soybean yields and to determine whether to recommend management practice changes. Flooding reduced the number and size of the plants and the yields, ,but did not affect number of pods, size of seeds or quality of seed. We no have an extensive data set of soil and plant properties and associated weather and flooding duration information that will allow us to determine which factors have the greatest effect on soybean yield in flooded fields and how to predict future flooding effects. This is important to farmers and farm advisors because it will help them avoid yield loss due to flooding in soybean fields.
Technical Abstract: Flooding is a major problem that reduces soybean growth and grain yield in many areas of the world. It is estimated that flooding for as little as two days may reduce soybean yields by 25% but the extent of the injury is determined by the interaction of many factors including variety, growth stage, flooding duration, soil type, fertility level and pathogens. In this sstudy, we conducted on-farm research in six fields in central Ohio that were prone to flooding. Heavy rainfall in mid June and early July in 1998 flooded all the fields. Each field was mapped by GPS and two transects, each 9 m wide, were designed to span across the lowest area within each field. Each transect was divided into plots of 9 m x 9 m according to flooding duration: no flooding, 1-3 d, 3-6 d, and > 6 d. Soil, plant, grain yield data and grain protein and oil content were collected for each plot. Infrared photographs and weather data were collected by remote sensing. The eresults were superimposed using the ArcView GIS software. Flooding significantly reduced plant count, plant height and grain yield at five of the sites. However, flooding did not affect pod number, seed size, or grain protein and oil content. Flooding consistently reduced the N concentration and increased the Ca, Mg, Fe and Al concentrations in soybean leaves. Flooded soils tended to have higher pH, organic matter and CEC. There was also a trend toward higher concentrations of K, Ca, Mn, and Zn in flooded soils while the concentrations of B tended to be lower. The interaction of these factors in reducing soybean grain yield is being determined in a statistical model. The determinant factor(s) that reduce soybean yield in flooded fields, once identified, will assist in the development and testing of flood tolerant varieties.