Micronutrients: Benefits of micronutrients for plants

Last updated on May 31st, 2023 at 03:38 pm

Benefits of micronutrients for plants, Micronutrients are essential elements that plants require in large quantities for proper growth and development. These nutrients play vital roles in various physiological processes, including photosynthesis, energy production, and structural formation.

Plants require at least 20 nutrients to survive, of which 17 are obtained from the soil. Nutrients are not required in equal amounts; some require more and some less. But all are essential for sustaining life. Plants that consume fewer of the 11 nutrients are called micronutrients. Boron is a micronutrient. It is not active in soil or plant bodies. In soil it exists as borate and borate silicate minerals. The average amount of total boron in topsoil is usually 10 ppm, but the amount of available boron is much less than 1 ppm. The critical level of available boron in soil is 0.20 ppm and the optimum level of boron in any soil is 0.45-0.60 ppm. The amount of boron in plant cells is usually 20–100 ppm, if the amount is less than 15 ppm, there is a deficiency, and if it is more than 100 ppm, toxicity may occur.

Micronutrients: Benefits of micronutrients for plants

Plants require 16 nutrients for normal growth and nutrition. Among these 7 nutrients, iron, zinc, boron, molybdenum, copper, manganese and chlorine are required in very small amounts by plants. For this reason, they are called Anukhadya. Although required in very small amounts, deficiency of any one of them disrupts normal plant growth, resulting in reduced yield. This problem is currently seen in every district of the state. Deficiency of zinc, boron and molybdenum has been observed in some regions especially in red kankur soil region.

Micronutrients are essential minerals that plants require in small quantities for their optimal growth and development. These elements include Sulfur (S), Zinc (Zn), Boron (B), Molybdenum (Mo), Iron (Fe), Manganese (Mn), Copper (Cu) etc. While plants also need macronutrients such as nitrogen, phosphorus, and potassium in larger amounts, micronutrients are equally indispensable for their well-being.

Symptoms of iron deficiency:

Iron deficiency symptoms are mainly seen in the young leaves of the plant. In young leaves, the number of green cells in the veins decreases and gradually turns yellow. And later all the leaves of the plant lose their green color.

Symptoms of zinc deficiency:

Zinc is essential for enzyme activity and the synthesis of growth hormones. It facilitates the production of auxin, a hormone responsible for cell elongation and root development. Zinc also plays a crucial role in seed formation and overall plant immunity.

Symptoms of copper deficiency:

Copper is an essential micronutrient that assists in the formation of chlorophyll and lignin, which provides strength to plant cell walls. It aids in enzyme activation, photosynthesis, and the metabolism of proteins and carbohydrates.

Symptoms of manganese deficiency:

Manganese is essential for photosynthesis, enzyme activation, and the breakdown of carbohydrates. It contributes to chloroplast development, regulates the opening and closing of stomata, and aids in the utilization of nitrogen.

Symptoms of boron deficiency:

Boron is involved in the production of cell walls and membranes, facilitating proper nutrient uptake and the movement of sugars within plants. It also influences pollen germination, fruit development, and the metabolism of plant hormones.

Symptoms of molybdenum deficiency:

Molybdenum is a critical element for nitrogen fixation and nitrate reduction. It aids in enzyme activation, facilitating the conversion of nitrate to ammonia, which is vital for protein synthesis.

Symptoms of chlorine deficiency:

Chlorine is involved in photosynthesis, aiding in the splitting of water molecules and the release of oxygen. It also helps regulate the stomatal opening and closing, thus influencing plant water balance.

The Impact of Deficiencies:

Insufficient levels of micronutrients can lead to deficiencies in plants, resulting in stunted growth, yellowing leaves, decreased flower or fruit production, and increased susceptibility to diseases and pests. Addressing these deficiencies through proper supplementation is essential to ensure vibrant, healthy plants.

Methods of Application:

Now that we understand the significance of micronutrients, let’s explore different methods of applying them to plants:

Foliar Spray:

For many crops, foliar sprays are frequently used to apply micronutrients, particularly iron and manganese. Because they are typically less expensive, soluble inorganic salts are frequently preferred for foliar sprays over synthetic chelates. Tissue sampling is the most popular technique to identify deficiencies during the growing season, though foliar spray trials with one or more micronutrients can be used to diagnose suspected deficiencies. Usually within the first few days, deficiencies are corrected, at which point the entire field may be sprayed with the appropriate micronutrient source. To increase the adherence of the micronutrient source to the foliage, sticker-spreader agents should be added to the spray. Due to the high salt concentrations, caution should be exercised to prevent leaf burn.

ADVANTAGES OF FOLIAR SPRAYS

• Application rates are significantly lower than rates for applying to soil.
• The application of uniformity is simple.
• Deficiencies can be corrected during the growing season because the application of the nutrient produces a nearly immediate response.

DISADVANTAGES OF FOLIAR SPRAYS

• If the salt concentrations in the spray are too high, leaf burn could result.
• When plants are small and the leaf surface is insufficient for foliar absorption, nutrient demand is frequently high.
• Spraying should not be put off until the onset of deficiency symptoms in order to achieve maximum yields.
• There is little residual effect from foliar sprays.
• Unless they can be combined with pesticide spray applications, application costs are higher if more than one spray is required.

Soil Application:

Applying micronutrients to the soil allows plants to absorb them through their root systems. This can be done through granular fertilizers, slow-release pellets, or water-soluble solutions.

Hydroponics:

In hydroponic systems, plants are grown in a nutrient-rich water solution, ensuring direct access to all required micronutrients. This method offers precise control over nutrient levels and uptake.

Soil Amendments:

Organic matter and compost can be added to the soil to enhance its nutrient content over time. This gradual release of micronutrients supports long-term plant health.

Sources of Micronutrients:

Micronutrients can be obtained from various sources, both organic and inorganic. Let’s explore some of the common sources:

Organic Sources

1. Compost: Organic compost is an excellent source of micronutrients. It enriches the soil with a balanced mix of essential elements.
2. Manure: Animal manure contains micronutrients that can be gradually released into the soil, promoting long-term fertility.
3. Vermicompost: Produced by earthworms, vermicompost is rich in micronutrients and beneficial microorganisms, improving soil health.

Inorganic Sources

1. Fertilizers: Inorganic fertilizers are specifically formulated to provide plants with the necessary micronutrients. They are available in various compositions and can be tailored to meet specific plant requirements.
2. Chelated Fertilizers: Chelated fertilizers contain micronutrients in a form that is easily accessible to plants. They are particularly useful in addressing deficiencies in alkaline soils.

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