Some of you may be familiar with new superior grass varieties like TifTuf Hybrid Bermuda. But what does the hybrid mean, and how are grasses like this created? In this blog, we’ll explain how…
Hybrid Turf Varieties
Technically all turfgrass varieties are hybrid varieties, in that they are seedlings that are the result of cross-pollination of plants with different DNA.
Interspecific hybrids are seedlings from cross-pollination of plants of different species.
F1 hybrids are the first seed from a selective cross-pollination of the same or different species. They may or may not be capable of producing seed. F2 is the second generation of these fertile F1 seedlings.
Seeded Hybrids
Seeded hybrid varieties are developed by natural cross-pollination of two or more parental lines.
Turfgrass Hybrids
Turfgrass hybrid varieties do not breed true, meaning that the seedlings they produce are different and not physiologically the same. With every seed being genetically different, over time you will see segregated patches which gradually become visible, especially during the cooler months.
This means that hybrid varieties require vegetative propagation to maintain the original plant’s phenotype or DNA. These are known as clonal varieties. Those that are hybrid varieties vegetatively propagated from clonal plants or an individual seedling selection.
Vegetatively propagated couch hybrid varieties are developed by a selection of superior plants from established seeded or vegetatively propagated plantings.
Triploids
This is where things get a little bit more scientific, but we’ll try to keep it simple…
The branded varieties are primarily known as triploids, which have 3 sets of chromosomes. This includes hybrid couch or bermuda grasses, like TifTuf.
TifTuf has proven itself to be the very best couch grass available through extensive trials and testing throughout Australia and the US where it was bred.
The name “triploid hybrid” comes from its two sets of C. dactylon (N=36) and one set of C. transvaalensis (N=18) chromosomes.
The couch triploid hybrids are Interspecific hybrids developed by cross-pollinating plants of Cynodon dactylon known as Bermuda grass and Cynodon transvaalensis, known as African Dogtooth grass.
Propagation
These hybrid plants are sterile and incapable of producing seed.
This means the commercial production of these triploid couch hybrids needs to be entirely vegetative as instant turf, sprigs, or plugs.
So, if we specifically look at TifTuf for example. TifTuf has uneven sets of chromosomes being a Triploid, does not produce pollen and is considered sterile. If by chance TifTuf produced a seed, it would not replicate TifTuf’s phenotype.
Turf quality of vegetatively propagated couch triploid hybrids is consistently higher than the quality of seeded common couch hybrids.
Therefore, commercial hybrid turfgrass varieties, that are kept physiologically the same in replicated tests, are consistently superior to seeded varieties.
TifTuf Hybrid Bermuda
All accredited TifTuf turf suppliers in Australia grow all their material from foundation plant material that is then sprig planted and established.
This ensures TifTuf’s trueness to type. It is an incredible grass with a specific set of traits that make it stand above all others, so it’s important that it’s kept genetically the same.
Certified TifTuf turf fields are then audited and assessed for genetic purity to ensure that the grass harvested is 100% pure TifTuf Hybrid Bermuda. This is conducted through AusGAP, Australia’s Genetic Assurance Program for turfgrass.
To make sure you are getting the real deal when it comes to the turf variety you buy, make sure you buy it from an accredited turf supplier who can supply the AusGAP Certification certificate for proof of authenticity.
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