Molybdenum for soya, the key to a healthy crop
Soya as a leguminous crop has a high sensitivity to molybdenum. This nutrient is required in very small amounts, but is fundamental to crop production. Molybdenum is required for nitrogen metabolism. In legumes this includes the fixation of atmospheric N into plant usable nitrate. This is carried out in the root nodules of the plant by nitrogen fixing bacteria from the Rhizobium family that have a symbiotic relationship with these crops.
The N-fixation story is widely reported, but another key role for molybdenum is the utilisation of the fixed-N. As part of the Nitrate Reductase enzyme the nutrient is part of the system that allows the plant to use the nitrate it has taken up.
Brazil has a soya bean production area of 12,000,000 hectares, of which a substantial amount is on poor and acidic soils. Molybdenum is applied via seed treatment due to the quantity required and the nature of this application method allowing placement locally. The growth and development of the root system in the early stages is of key importance as a young under developed system struggles to access the limited molybdenum supply from these soils. As the roots grow the nodulation develops and optimal root system establishment in these stages will lead to a higher level of crop production.
In Brazil, as well as many other countries globally, micronutrient applications via seed treatment is being looked on increasingly due to efficiency of delivery, consistency of delivery and the outcome of excellent uptake into the developing seedlings.
Author: James Craske, Brazil
Published: June 2000