Today we are joined by farmer Lavern Johnson and Dr Lyndon Porter, a pulse crop plant pathologist with the USDA Agricultural Research Service. After 20 years of experience as a pulse crop grower, Lavern Johnson brings real world issues to the forefront today by sharing why he is unable to plant pulse crops this year. Multiple organisms have accumulated in his fields over time leading to significant root rot and making his fields unable to support pulse crops for up to 8 years.
Rarely, does any grower have fusarium or pythium as solo pathogens causing damage. The root rot complex employs multiple organisms causing more than one infection to be present. Nematodes can also contribute by wounding the plants allowing fusarium better access.
“Fusarium might be the one that starts weakening the plant and it might be aphanomyces that finishes the life of the plant…..to my knowledge there’s no soil tests that they can use to determine the level of disease that’s out there.” - Lavern Johnson
Dr. Porter describes some of the options farmers have to avoid this situation. He suggests some standard cultural practices that can help. Soil compaction restricts the growth of the roots which can encourage fusarium growth. Maintaining a soil pH outside of the range most supportive of fusarium can also be helpful. Identifying best varieties, seed depth selection, soil fertility and managing wet fields also contribute to better control of the root rot complex of disease. Residual herbicide is another factor that can affect a plant’s susceptibility to root rot.
“I’ve seen a lot of herbicide damage that is causing poor plant vigor impacting yields and stressing plants out which causes greater root rot issues.” Dr. Lyndon Porter
Dr. Porter goes on to suggest evaluation of seed health to promote the healthiest plant. He feels a commonly overlooked factor is the health of the seed itself at planting to provide the best opportunity to maximize yield.
This Week on Growing Pulse Crops:
- Meet Lavern Johnson, a former pulse crop grower, who has had to shift away from pulse crops due to repeated episodes of root rot
- Also meet Dr. Lyndon Porter who provides us with some suggestions to avoid root rot
- Explore the many factors that contribute to the root rot complex
- Learn what cultural practices can be employed to provide the best environment for the plants