Research Highlights

University of Arkansas Breeding Program Adapts to Agronomics

By Laura Temple

Changes in agronomic practices or challenges should prompt adjustments in breeding, according to Leandro Mozzoni, associate professor of soybean breeding and genetics for the University of Arkansas. 

“I see myself as an agronomist who conducts soybean breeding as a subset of agronomy,” Mozzoni says. “I have found that understanding how to grow a crop improves the ability to breed improved varieties.”

 That philosophy undergirds the soybean breeding program he leads, funded in part by the Arkansas Soybean Promotion Board. The University of Arkansas program develops high-yielding soybean varieties adapted to environments and challenges in Arkansas.

“For example, soybeans under flood irrigation need different characteristics from dryland soybean varieties,” Mozzoni explains.

He notes that his program is working on a wide variety of soybean genetics, but that they adapt as needed to key challenges. Breeding is a tool that helps farmers continuously improve as agronomic factors change. Shifts in weather patterns could lead to changes in disease pressure. Changing crop rotations impact soil pests and nutrient availability. Herbicide resistance in weeds influences genetic technology systems.

Incorporating root-knot nematode resistance into base genetics

One major project funded by the Arkansas Soybean Promotion Board has been focusing on new varieties and germplasm with resistance to nematodes and diseases. That project began focusing on fast-tracking soy germplasm with southern root-knot nematode (SRKN) resistance in 2021. 

“The checkoff invests in research to keep soybean farmers on the leading edge,” says Doug Hartz, a professional farm manager based in Stuttgart and member of the Arkansas Soybean Promotion Board. “As a board, we fund practical independent research that addresses challenges we are seeing in producers’ fields to improve their operations.”

“Right now, soybean cyst nematode (SCN) resistance is part of the base genetics used in a wide variety of public and private breeding programs,” Mozzoni says. “However, SRKN resistance is not widely available.”

This project will screen germplasm to identify SRKN resistance. Then, with tools like marker-assisted breeding, use of a winter nursery, and a focus on volume, his team will incorporate that germplasm into a wide variety of Maturity Group 4 soybeans so it becomes part of base genetics available to all. Results of this work will be shared with both public and private breeding programs.

“Our process will be similar to what was done with SCN resistance years ago,” he says. “We plan to shock the system with SRKN-resistant material so that within a decade, farmers will have easy access to SRKN-resistant soybean varieties that fit their other agronomic needs, as well.”

Developing Genetics and Breeders

This breeding program’s focus on germplasm with SRKN resistance will benefit soybean farmers regionally and nationally as the pest spreads. At the same time, Mozzoni emphasizes the value this public program has in developing soybean breeders.

“Breeding training with real agronomic problems gives our students valuable experience they will take with them when they are hired to be commercial breeders,” he says. “We share our germplasm, our knowledge, and our people in a way that benefits the entire soybean industry.”

He believes that the actual breeding experience students gain at the University of Arkansas improves the quality of work being done in both public and private programs. Breeders who understand how agronomics impact their work are better able to develop soybean varieties that help farmers grow a high-yielding, high-quality crop. 

Published: Oct 11, 2021