Frequently Asked Questions (FAQ)
Trichoderma is a naturally occurring fungus found in soils worldwide. It has been studied extensively as a contaminant in mushroom production systems, as a component of industrial cellulase production, as well as for its plant associated biocontrol and growth promotion properties.
Trichoderma can be isolated from plants and all soil types around the world. That is, it can be free-living or it can grow endophytically (inside the plant). Among endophytic strains, some grow only in the roots while others also grow into the above ground parts of the plants.
There are many strains of Trichoderma found around the globe. The differences between strains are the same as the differences between different people: genetics. Just as only a select few humans can swim the English Channel, very few strains of Trichoderma have beneficial or consistent effects in agricultural systems. The very first commercialized strain of Trichoderma was T22, developed in the 1980’s by ABM’s Chief Science Officer, Dr. Gary Harman, back when he was faculty at Cornell University. Subsequently, many Trichoderma products have come onto the market, some of which contain T22 or some other purified strain, and others that contain wild or uncharacterized strains or strain mixtures. One factor that distinguishes different strains is the trigger molecules they produce. These triggers are how Trichoderma communicates with its environment, including plants. Different strains produce different triggers and therefore elicit different responses from their plant hosts.
Each ABM’s strains is broadly adapted so that it can thrive in environments ranging from Alabama to Minnesota to South Africa. They have been selected to give consistent performance from year to year and across environments. In addition, different strains perform best in combination with specific crop plants, therefore ABM’s Trichoderma products contain different, patented strains depending on if that product is for corn or wheat or soybeans or cotton or something else.
There are many ways in which Trichoderma works with the plant including antibiosis, competitive exclusion, facilitation of nutrient absorption and uptake, and induction of plant gene expression. There is a great deal of genetic variation between strains which means that different strains may interact with plants by using some, all or even none of the above strategies. The strains that are of the most use to agriculture, influence plant gene expression to enable to plant to perform to the maximum of its genetic potential, resulting in better resistance to stress, bigger and greener plants, and increased yields. All of ABM’s strains are known to work with plants in this way.
Plants can benefit from multiple Trichoderma strains because each strain is unique. That is, different strains have different genetics, which means that they possess different traits. This is the same as corn genetics: some hybrids are early maturing while others resist lodging. What underlies these different performance characters are genes. Trichoderma strains show a range of different performance characters and one may confer drought resistance whereas another may confer disease suppression. Inoculating plant roots with only one of these strains provides only one of these traits, however inoculating with both strains can provide an additive effect with both traits being effected. This synergy does not always occur which is why ABM’s combination products are continually tested for strain compatibility and trait additivity.
Trichoderma strains with agricultural value require the presence of living plant roots. When the crop is harvested and the roots die, that season’s Trichoderma also dies. There are strains that are free-living in the soil and that do not require plant roots, however because these do not establish an endophytic, symbiotic relationship with plants, they’re of little value as agricultural biologicals..
Trichoderma can be applied as a seed treatment on farm or at the seed treater in addition to in furrow, root drench, root dip, as part of an irrigation system, and even a foliar spray. ABM specializes in seed treatments, however our products are used in many different cropping systems both domestically and internationally and can often be adapted to the needs of the region and crop. Our pipeline products are being developed with these different applications in mind.
There are about 23 Trillion Trichoderma spores per acre in typical farmland. ABM recommends applying its Trichoderma products at a rate about 10,000x lower than this. So, another question is, won’t the effect of the Trichoderma applied to the seed be completely washed out by the native Trichoderma in the soil? The answer to both questions is that the vast majority of the Trichoderma already present in the soil can’t form the endophytic, symbiotic relationship with the plant that our strains can and, further, the native strains generally have anagrinomically neutral (at best) interaction with plants. The difference between what is applied to the seed and what is naturally in the soil is genetics. ABM has worked hard to select superior genetics that will provide consistent and excellent agronomic performance.
That’s a secret! However, it involves long term testing of candidate strains in our R&D facility, greenhouse testing, and subsequent field testing with crops of interest. A successful strain will perform at a high level in all of these situations over many environments and over many seasons. Through this process we develop strains that show enhanced performance in specific crops and these are then formulated into our crop specific products.