By John Brien, AgriGold agronomist
Upon planting a seed into the medium called the soil, one could assume that it is tucked into a warm and inviting environment, where nothing bad can happen to it. If a grower had that assumption, they would be WRONG!
When a grower plants a seed into the soil, the war begins. The war is between the seed and the “bugs” that are present in the soil. The seed’s goal is to sprout and grow, while the bug’s goal in today’s discussion is to decompose the seed along with any other organic matter, making it nonviable. Both sides are ready to wage war, but how do they plan on winning?
The bugs: Who are they and how do they win?
The bugs in this story are the fungi found in all soils. The fungi that battles corn seeds and seedlings are Pythium and Fusarium. The reason the bugs battle corn seeds and seedling is due to their role in the soil cycle. The bug’s role in the soil is to decompose any and all organic matter, much like the acids in our stomachs. Farmers like these bugs when they decompose corn, wheat and/or wheat residue, so next year’s crop can be planted and use the nutrients released from the decomposed residue. Unfortunately, these bugs do not differentiate between residue and valuable seeds. If there is material to decompose, they will attack it, with full vengeance.
There are three strategies bugs use to win the battle. The first strategy the bugs use is time. The bugs will have a better chance of outnumbering and overtaking a corn seed or seedling if the corn is slow to grow and develop, thus giving the bugs more time to attack and win. Conditions such as day time temperature in the mid to low 60s, wet to saturated soils and cloudy days are a bug’s dream environment to prosper due to the slow growth of corn plants in these conditions. The second advantage is numbers. There are billions of bugs attacking one seed or seedling, given time and numbers, the bugs tend to win. The third advantage is skill. The bugs only have one job and they are masters at their craft and their only goal is to eat and decompose. So, with skill time and numbers, the bugs can be a tough enemy to defend against.
The seeds: How do they out-maneuver the bugs?
Corn seeds and seedlings have no natural defense against their enemy, so they must rely on some allies for victory. The first ally of a corn seed is the seed treatment that comes on the seed. The seed treatment is designed to be the first line of defense for the corn seed. Seed treatments are designed to protect the seed while it is beginning its new life. Unfortunately, the seed treatment only protects the seed for approximately 21 days. After that critical window, the seed must then rely on its second ally.
The second ally and the most successful defense against the bugs is good growing conditions. Good growing conditions allow the corn plants to utilize the only method available to them that can truly beat the bugs and that is to outgrow them. Meaning the corn plant grows to a size where the bugs are no longer a factor for defeat. The corn plants need to establish a good set of nodal roots to ensure a complete victory over the soil bugs.
The war is raged every year in the Eastern Corn Belt, on every soil type and on every farm. Planting into a warming trend and into soils that are not saturated provides a battlefield that is favorable to our seed. Any help a grower can provide will reap huge rewards as the enemy is small but mighty and never seems to get tired!