March 28, 2024

Field Checkup Series: Diagnosing the cause of soybean leaf chlorosis

As soybeans enter the mid- to late-season growth stages, farmers may notice yellowing leaves, called leaf chlorosis, which can indicate low fertility, disease or restricted root growth. Soybean plants acquire nutrients from the soil and through nitrogen fixation in the root nodules throughout the growing season.

Pod fill is a period of high nutrient demand, and if the soybean plant cannot absorb needed nourishment to support seed development the plant will remobilize nutrients from the stems and leaves. As nutrients are reallocated away from the leaves they tend to yellow, which is an indication of nutrient deficiency.

To determine a cause of nutrient deficiency, evaluate fields for any condition that can jeopardize nutrient uptake by the roots such as soil compaction, water-saturated soils or insect feeding. Some soybean diseases like sudden death syndrome and brown stem rot can also resemble nutrient deficiency symptoms.

Channel Seedsmen conduct field evaluations to help farmers determine what conditions may be causing soybean leaf chlorosis. They assess the agronomic needs on farmers’ fields to help plan a fertility program for the next season’s crop and recommend seed products that are an ideal match for the anticipated growing environment.

As the end of July approaches, Illinois farmers should evaluate soybean fields for overall plant health and insect pressure. While nutrient deficiency symptoms can give you an idea of management decisions to change for the future, the ability to maintain and increase yield potential can be realized by knowing your insect and disease pressure in the field during the critical pod setting time. The field intelligence farmers gather now can inform product selection and management strategies for the next season.

The next few weeks of observations and notes from Seedsmen can help provide a picture of fall yield potential and set the stage for next season's product selection. Visit channel.com to learn more about the Channel Field Check Up Series and to access more agronomy tips and insights.

Channel®, Channel® and the Arrow Design® are trademarks of Channel Bio, LLC. © 2020 Bayer Group. All rights reserved.