Control of Iron Chlorosis in Plants

The yellowing of leaves in plants is caused by the lack of the green pigment that enables the photosynthesis process, i.e., sugar production. This green pigment is known as chlorophyll in biology.

In the event of chlorophyll deficiency, interveinal chlorosis occurs throughout the plant or in certain parts. Consequently, yellow leaves form instead of dark green leaves.

The fruits of a plant under chlorotic effect become bitter. If this condition persists, the plant may die over time.

What Are the Causes of Iron Chlorosis?

Iron chlorosis is most commonly observed in soil structures with a pH higher than 7.0 and in calcareous soil structures. Iron is present in almost all soil structures on earth. However, due to chemical reactions within the soil, this iron becomes unusable for plants.

In soils with a high pH structure, the iron element reacts with hydroxide, carbonate, and oxygen to form solid substances that are difficult for plants to dissolve.

You can detect these resulting solid substances in the soil structure and around the plant. Because these substances do not dissolve in water, they cannot be absorbed by the plant. This leads to the formation of iron chlorosis.

How Sensitive Are Different Plants to Iron Deficiency?

Iron deficiency can occur in fruits, vegetables, flowers, and trees. This deficiency can be at low, medium, or high levels.

Soil Control to Remedy Iron Deficiency

Soil treatment is generally applied in the autumn or at the beginning of spring. When applying, a chemical raw material containing a high-concentration iron source should be selected. For example, compounds in concentrations containing over 20% Fe content will provide significant benefits for solving the problem. Additionally, combinations containing a mixture of iron sulfate and sulfur are the most effective methods.

When applying, it is not correct to cover the entire soil surface or the base of the plant with the treatment substance. For this, the most suitable method is to open holes with a diameter of 5 cm and a depth of 40 cm, arranged at intervals of approximately 50-55 cm.

One of the main reasons for using sulfur is that it lowers the pH of the soil by neutralizing the calcareous area over time. When acidification is carried out using iron sulfate, it converts the iron into a form that can be absorbed by the plant's roots.

Among the Iron Chelates that work best in soils with high pH levels is EDDHA. Although it takes about a year to see the effect of this chemical compound, it is among the most effective methods.

To benefit from this compound, it is sprinkled in dry form on the soil surface in the spring before the plant grows and then watered. It can also be applied by opening wells near the plant.

Foliar Treatment to Remedy Iron Deficiency

When applying foliar treatment, it is applied to the affected parts of the plant. Treatments performed with this method yield results within a few days. If deficiencies persist, it can be applied continuously. Treatment methods using chelates remedy iron chlorosis deficiency.

How is Foliar Application Performed?

To remedy iron deficiency in plants, 0.5% Iron Sulfate applications in foliar sprays are preferred due to both cost advantage and ease of application. The application should be performed when there is no sunlight and on a cool day.

A 2% Iron Sulfate solution is applied to field crops.

Use of Iron Sulfate to Remedy Iron Deficiency in Plants:

For plants, iron is present in the structure of chlorophyll that remains outside of the chlorin ring, as well as in basic metabolic processes such as chlorophyll formation and photosynthesis. Iron sulfate can increase iron intake in plants by being applied directly to the soil. This is usually done by adding iron sulfate solution in liquid form to irrigation water or by sprinkling it onto the soil surface. Iron sulfate is mixed into the soil during irrigation, ensuring it is absorbed through the roots of the plants.

The Iron Sulfate form is generally found as Iron Sulfate Monohydrate or Iron Sulfate Heptahydrate.