We’re looking forward to Commodity Classic
at the end of February. Given the conversations surrounding #plant2020 and the upcoming growing season, let’s focus on the importance of boron in corn and soybean production, as well as the adverse effects boron deficiency can have on reaching yield potentials.
Maximum yields call for both micro and macro nutrients to be available when and where a plant requires them. And, as one of eight essential micronutrients, boron is critical to reaching corn
crop yield potential.
Boron acts as a nutrient utilization catalyst by helping a plant to more efficiently metabolize nitrogen (N) by reducing nitrate reductase activity—the molybdoenzymes that reduce nitrate to nitrite. Research also shows that boron plays an important role in rhizobial N fixation, actinomycete symbiosis, and cyanophyceae heterocyst formation in soybeans and other legumes.
Conversely, boron deficiency in corn and soybeans adversely impacts the metabolism and growth of the crop. Deficiencies impact cell-wall structure, inhibits root elongation, reduce plasm membrane stability, and a host of other metabolic functions within the plant.
Making boron pay on corn and soybeans
If you’re trying to grow anything at or above 200 bushels of corn per acre, you will have to add more boron into your fertilizer plan to prevent deficiency onset. Boron fertilization has also been shown to increase soybean yields by as much as 18 bushels per acre (Gitti, 2018).
Beyond correcting boron deficiency and availability within the soil profile, the question of “How much boron do I need,” is relative to what your yield goals are. Higher crop yields will always require higher boron fertilization. Remember:
Boron is a catalyst for the uptake and ultimate availability of the other 13 essential nutrients.
Deficiency, on the other-hand, can present subtly while significantly diminishing a crop’s yield capacity. One marked symptom of boron deficiency in soybeans is delayed maturity and leaf senescence. Under normal field observation conditions, how easy is it to visually assess delayed maturity and leaf senescence?
Boron deficiency initially impacts the roots of a plant in soybeans, corn, and other plants—causing the development of lateral shoots with brittle petioles and inhibiting peak root performance.
Optimal boron availability during soybean reproductive stages has been proven to:
- Stimulate root growth and nodule fixation
- Increase branching, flowering, bloom retention and number of pods
- Stimulate better seed development
All of which leads to increased yield.
Corn is also susceptible to boron deficiency, perhaps in an even greater capacity than soybeans. When boron levels are too low, the corn plant’s cell walls and stem cells disintegrate, preventing growth from the points of damage. Once cells have been damaged, plant growth is stunted, tassels fail to develop properly, and kernels do not set on the ear. All of these issues culminate in a less than optimal yield.
Boron deficiency can also be caused by a host of environmental conditions outside of crop uptake. High soil pH will reduce the availability of boron as can leaching as a result of heavy rainfall events or mismanaged irrigation.
A lack of organic matter, those soils severely degraded from repetitive tillage practices and coarse-textured soils, will naturally contain less available boron, as will excessively dry soils.
Test for success
is the best indicator of available boron in agricultural soils, however because of the volatility and mobility of boron within the soil profile, testing should be done strategically in proximity to the planting season of the cash crop being planted. Fertilizer applications should be calculated based on recent soil test results.
should be run periodically throughout the growing season to provide the correct information needed to “spoon feed” the developing cash crop. Newly developed plant tissue should be sampled for corn and soybean crops.
Boron and the 4Rs
If testing indicates that boron needs to be applied, consider your cropping system to decide about the right source, right rate, right time, and time place.
is an excellent choice, allowing multiple foliar applications during critical reproductive stages, and can be combined with other applications of herbicide and insecticide. Solubor
is cost effective and allows farmers to prepare his/her own tank mix.
is a good dry-application choice early in the season when you want to apply boron through the soil as a standalone application or in NPK blends. All boron in Granubor
is plant available and it allows for adequate availability of boron throughout the critical stages of the growing season.
Douglas Gitti. 2018. Fundação MS. Brazil.