Boron – A Key Micronutrient
What is Boron?
A balanced supply of essential macro and micronutrients is one of the most important factors to achieve higher crop yields. Boron (B) is one of 8 micronutrients needed for proper plant growth. Lack of B in plant tissue can reduce cell wall function and stability, cell elongation, root growth, nutrient uptake and crop yields. Boron (B) is a micronutrient and is considered the most deficient micronutrient in the world after Zinc. Boron (B) is essential for cell wall formation and fast-growing areas of the plant, such as reproductive structures, depend on the Boron (B).
What Do We Know About Boron?
Agronomically speaking, the ideal Boron (B) management program should consider factors such as crop, soil type, environment and Boron fertilizer source. Any source that contains Boron in the form of sodium borate is considered highly soluble with commercially available products in both dry and liquid forms. Nutrient sources containing Boron in the calcium borate form, on the other hand, typically have intermediate to slow-release qualities. These release properties affect soil mobility, which is unrelated to nutrient mobility in plants.
Some growers prefer to deliver a portion or all their Boron needs using foliar applications due to the convenience of a ‘free pass’ when combined with a crop protection or irrigation application and the fact that this approach typically leads to the quickest response from a tissue-test standpoint.
The Benefits of Boron in Plant
Improves Seed Set: Boron improves seed set under stressful conditions.
Improves Cell Walls: Although required in small amounts, Boron is a component of all cell walls in the plant.
The Challenge with Boron Management
Although Boron (B) is considered the most deficient micronutrient in the world after Zinc, dynamics of B use in plants and soils have continued to puzzle farmers, agronomists and researchers for decades. In short, B is a micronutrient that’s needed in relatively small quantities. The soil-mobile nutrient B is commonly applied in a form that’s immediately soluble and susceptible to loss at the time of application, which means ensuring season-long availability can be difficult.
When Do Plants Need Boron Most?
In addition to nutrient distribution, adequate plant availability is also influenced by solubility properties of different Boron sources. Season-long availability is critical in grain crops like cornand soybean, which require B for plant development during critical vegetative and reproductive growth phases. While sodium borate-based fertilizers are immediately plant-available at the time of application, their highly soluble nature can make them subject to loss by leaching and this B may not be available for late-season plant demands. On the contrary, more slowly soluble B sources (e.g., those with calcium borate) may provide adequate B for late-season plant requirements, but there is a risk of B not being available quickly enough for early-season plant needs.
Boron Deficiency in Corn
Proper Rate and Placement
The line between deficiency and toxicity is narrower than other essential nutrients. Farmers should apply at proper rate and with proper placement.
Courtesy: http://www.cropnutrition.com