The 2019 growing season is proving to be another year of difficult weather patterns, with lack of moisture and the looming threat of hail plaguing the Prairies.
As we all know, lack of moisture and hail put the plant under significant physiological stress - damaging the plant, stunting its growth, and ultimately affecting yield.
Figure 1: Hail Damage to Wheat. Inset: Closeup of Hail Damage to Wheat
Leaf Tissue Damage: During hail, the photosynthetic factory of the plant (the leaves) can be significantly affected. When the leaf tissue is damaged, the leaf's ability to take in sunlight to create photosynthesis is compromised and plant experiences stress.
Repair Mode: Upon leaf tissue damage, the plant goes into "repair mode" and moves a large portion of its nutrients and various metabolites just around the damaged sites to help fortify the healthy plant tissue.
Systemic Acquired Resistance (SAR): The plant is quite smart as it will move various sugars, metabolites, and amino acids from the irreparable, damaged tissue, to the healthy part of the leaves. The goal of the plant is to limit the amount of available 'food sources' in the damaged tissue so that the various pathogens and insects can not easily proliferate. The natural defense system of the plant is known as Systemic Acquired Resistance (SAR).
In order for a plant to actively engage Repair Mode and Systemic Acquired Resistance, it must be healthy and have a healthy and active root system.
The first step in dealing with hail damage is to assess if there is enough healthy 'green' tissue to target and help fix the plant. If there is enough healthy plant tissue, timing becomes critical. The goal is to help the plant in repairing itself as quickly as possible.
At this point, there are three objectives that can be effectively handled with nutrition:
If at this point the plant is deficiency in nutrients, and if a foliar nutrient application is delayed, the plant can prematurely switch the reproductive stage, rather than re- establishing its root system. The end result will be a significant reduction in the yield of the crop as the plant will not be properly developed to move nutrients to the grain or pods for filling.
At ATP Nutrition, our recommendation following hail damage is to apply as soon as you can get onto the field.
This will accomplish the three objectives listed above:
To learn more about how to protect your crop from hail, please speak with one of our ATP Nutrition reps.