Home

Research

Strain Collection

F.A.Q.

Glossary

Reading


Personnel

Sponsors

Listserv

News


Dr. Peter H. Graham
439 Borlaug Hall
1991 Upper Buford Circle
St Paul, MN 55406

For which legumes are commercial inoculants available and who makes them?

Legume inoculants come in different formulations (varying with the method of their application) to be used, and are specific to different legume species. Not all manufacturers supply inoculants for all major legumes, and the different formulations they sell may also differ with plant species. The range of inoculant types available for each major legume is available at http://www.philombios.com/inoculant_products.html

If the species of legume in which you are interested is not shown in this listing, "inoculant specials" can often be obtained from Nitragin; the Rhizobium Research Laboratory can also produce inoculants for a number of lesser known prairie and pasture legumes. Information on inoculants is likely to change because of the recent sale of several inoculant companies to Becker Underwood.

The preferred inoculant format for any legume should still be a sterile-peat based culture. However, inoculants may also be supplied in a non-sterile peat, as a liquid or frozen concentrate, or as a clay-based or peat granular preparation.

The norm in the USA is to include more one strain in each inoculant, but in Australia, Canada and France the inoculant usually contains only a single strain. Control of inoculant quality is also more formalized in Australia and Canada than in the U.S. Some of these differences are discussed under "Common questions on inoculants and inoculation".

Several companies manufacture peat base inoculants that already contain a sticker. This product can be applied directly to the seed, and is used without a delay while moistened, inoculated seeds dry. In Australia, some inoculants include Celstik^TM, an adhesive and stabilizer intended to ensure more uniform inoculant coverage of seed.

Several companies also manufacture products where molybdenum and/or fungicide is added to the seed at the same time as the inoculant. Molybdenum (Mo) and many fungicides are toxic to rhizobia and certainly should not be in contact with these organisms in an inoculant package. Where seeds are planted soon after inoculation, and into a good seed bed, it is possible that rhizobia and nodulation are not significantly affected. In instances where a significant delay between inoculation or planting and germination could occur, or where conditions in the soil are in any way adverse, such a combination of inoculant, Molybdenum and/or fungicide cannot be recommended.