Agronomy and Horticulture, Department of


Date of this Version



Sonderegger, E.B. 2013. High Yield Soybean Management: Planting Practices, Nutrient Supply, and Growth Modification. MS thesis, University of Nebraska, 2013.


A THESIS Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Master of Science, Major: Agronomy, Under the Supervision of Professors Greg R. Kruger and Charles S. Wortmann. Lincoln, Nebraska: August 2013

Copyright (c) 2013 Evan B. Sonderegger


Growers are constantly seeking ways to improve yield in soybean [Glycine max (L.) Merr.]. There has been much interest in the use of selected alternative practices to maximize soybean yield. These practices include planting soybean at higher than recommended seeding rates, planting soybean in narrow rows, breaking apical dominance to induce branching, application of strobilurin fungicides prophylactically to minimize disease and extend the seed filling period, the use of N fertilizer both in furrow and foliar applied, and the use of seed treatments to promote early stand establishment and health. Field studies were conducted at the University of Nebraska West Central Research and Extension Center in North Platte, Nebraska, and at the West Central Water Research Field Laboratory located near Brule, Nebraska and at Bancroft, Clay Center, Cortland, and Elba, Nebraska to determine how these practices affect soybean yield.

Increased seeding rate also increased soybean yield and 24.7, 43.2, and 61.8 planted seeds m-2 yielded 4.47, 4.79, and 4.79 Mg ha-1, respectively. Soil fertility, application of strobilurin and seed treatments did not affect yield. Decreases in yield were observed by destroying the apical meristem by both clipping at V2 and application of lactofen.

These results suggest that soybean yield is optimized in west central Nebraska by planting soybean at between 24.7 and 43.2 seeds m-2 but not applying lactofen or pyraclostrobin. Growers should be very careful in selecting alternative practices due to the possible reduction in soybean yield.

Advisors: Greg R. Kruger and Charles S. Wortmann