BORON IN AGRICULTURE

In addition to macronutrients such as Nitrogen (N), Phosphorus (P), Potash (K), Sulphur (S), Calcium (Ca) and Magnesium (Mg) plants also need micronutrients. Boron (B) is one of the seven elements described as micronutrients which are essential for plant health, growth and development. Although micronutrients are required in small quantities, they are as important as macronutrients in plant nutrition. Insufficient micronutrient nutrition may reduce crop yields and quality.

Functions of boron in plants:
• Nitrogen and Calcium metabolism
• Formation,transport and metabolism of sugars and other carbohydrates
• Proper pollination and pollen tube growth
• Wall lignin production and differentiation
• Formation of xylem vessels in roots and stems
• Increase the uptake of other nutrients
• Increases pest and disease resistance of plants when applied alone or in combination of other pesticides
• Quality and the yield increase

Boron Deficiency:
Deficiency in crops may be suspected on the basis of symptoms and by plant analysis, and also understood by soil analysis. Symptoms differ among plant species and can often be confused with other nutrient deficiencies that cause irregular growth. Boron deficiency can be corrected by the application of boron containing fertilizers depending on the factors such as; type of the soil, climatic conditions, plant species and previous cropping. Boron is only required in small amounts and the range between deficiency and toxicity is very narrow.

Boron Application:
Boron may be applied to the plants, as soil application, mixed with other fertilizers, dissolved in water and sprayed on the crop/soil or through irrigation water.

Boron as herbicide
Boron based herbicides are produced from borax and boric acid, and they are generally mixed with sodium chloride or other toxic chemicals. Boron effects digestive physiology of the insects.

Plants that are susceptible to boron application
Some crops show boron deficiency symptoms more commonly than others.

Boron Sensitive Crops:

Highly Susceptible	Moderately Susceptible
Alfalfa Apples Cabbage Sweet corn Cocoa Peach Celery Carrot Coffee Barley Coconut Bananas Cotton Cucumber Groundnut Beans Lettuce Pear Olive Mango Eucalyptus Broccoli Potato Soybean Lucerne Cauliflower Oil Palm Citrus Maize Radish Rapeseed Sugarbeet Sunflower Clover Papaya Rice

Boron Products used in agriculture:

Borax decahydrate and borax pentahydrate are most widely used borates as boron fertilizer. Sodium borates can be used as soil application and also as foliar application due to its high solubility. Colemanite which is a naturally occurring calcium borate is used especially in sandy soils as a slow release fertilizer which provides constant supply of available B in the soil. Disodium octaborate tetrahydrate is the most preferable boron product in agriculture since it has high solubility compared to the conventional boron products.

COLEMANITE
• COLEMANITE is calcium borate mineral with the formulation of Ca₂B₆O₁₁·5H₂O
• It is a slow-release boron compound
• It has low solubility of 0.81 g/lt at 25° C distilled water and alkaline pH of 9.5
• Rate of dissolution for colemanite is less then highly soluble sodium borates which prevents leaching of boron due to heavy rain falls.
• The use of colemanite also provides calcium to the plants which is an essential micronutrient like boron.
• The Calcium Borate mineral Colemanite is often used on sandy soils because it is less soluble and less subject to leaching than the sodium borates.
• It is usually applied as basal fertilizer.
• At serious B deficient condition, it should be combined with foliar spray ETIDOT 67 in practice.

ETIDOT-67
• ETIDOT 67 is a highly soluble borate powder for crop nutrient sprays and solutions.
• The High boron content of ETIDOT 67 makes it an economical source of boron for consumers.
• ETIDOT 67 having extremely high solubility & neutral pH is ideally suited for foliar applications.
• It is very widely used throughout the world for foliar application to fruits, vegetable and oil seed crops due to its easy solubility in cold water and neutral pH.
• ETIDOT 67 is a multi-function source of boron and can be used as direct application or blended with other liquid fertilizers, pesticides and insecticides for foliar spray.
• ETIDOT 67 is a highly concentrated, soluble B source that can be foliar applied as a liquid or dust.
• ETIDOT 67 is preferred to borax because it dissolves more readily.
• It is usually applied as foliar fertilizer.
• Application as basal fertilizer and top-dressing is also available.

ETIBOR-48
• ETIBOR 48 is a white free flowing granular product.
• It is highly soluble without any residue. This property makes ETIBOR 48 a versatile source of Boron in solid & liquid multi-micronutrient formulations, suspension fertilizers and also for direct application in soils.
• ETIBOR 48 is also very popular, containing about B 15%.
• It is a slow-released B fertilizer and usually applied as basal fertilizer.
• At serious B deficient condition, it should be combined with foliar spray ETIDOT 67 in practice.

BORIC ACID
• BORIC ACID is particularly a very effective B nutrient in highly alkaline soils & in crops that are susceptible to sodium.
• It is also used as an insecticide, herbicide and fungicide in food crops and orchards.
• BORIC ACID is white, crystalline which can be easily blended with liquid fertilizers, pesticides, insecticides recommended for Foliar Spray.
• It is usually applied as foliar fertilizer
• Application as basal fertilizer and top-dressing is also possible.

BORAX DECAHYDRATE
• BORAX DECAHYDRATE is the refined form of natural sodium borate.
• BORAX DECAHYDRATE is mainly composed of boric oxide (B₂O₃), sodium oxide and water.
• It is a mild, alkaline salt, white and crystalline,with excellent buffering and fluxing properties.
• When dissolved in water, it hydrolyzes to give mildly alkaline solution, thus capable of neutralizing acidic soils.
• It is an important multifunctional source of B₂O₃, particularly where the simultaneous presence of sodium is beneficial.
• BORAX DECAHYDRATE is used as a source of micronutrient B and can be blended with commonly used bulk / liquid fertilizers & micronutrient mixtures for Soil application or Foliar Spray.