4turf® leads the way in tetraploid perennial ryegrasses

Grass plants are wildly varied in their genetic make-up. Their variety even extends to the number of chromosomes in each cell. Most cultivated grasses – including turfgrass species – are polyploid: they have more than two sets of chromosomes.

08-04-2021

Among the turf grasses there is one big exception: all varieties of the main species, perennial ryegrass (Lolium perenne), are diploid. They have just two sets of chromosomes. Even in the wild there are no perennial ryegrasses with more than two chromosomes.

All that changed when we developed 4turf® – a range of perennial ryegrass varieties with four sets of chromosomes. With twice as many chromosomes, our 4turf® tetraploid varieties revolutionized the turf industry.

4turf® – the great tetraploid breakthrough

4turf® varieties came into being in 1991, the year that we created the world’s first tetraploid (4n) perennial ryegrass for turf. It was a game-changing moment for the industry, and the start of our leadership in the development of tetraploid perennial ryegrasses. 4turf® grasses perform so well, they have come to dominate many of the national turf-grass lists.

  • Three out of the three 4n perennial ryegrasses on the French national list
  • Seven out of the eight 4n perennial ryegrasses on the STRI turf-grass list
  • Three out of the four 4n perennial ryegrasses on the Scandinavian Scanturf list
  • Three out of the four 4n perennial ryegrasses on the German RSM list

None of the competing tetraploid perennial ryegrass varieties come near the performance of our 4turf® varieties.

Four chromosomes for outstanding performance

The four chromosomes in 4turf® varieties give a genetic boost to turf-grass performance in numerous ways, the most significant of which is increased stress-tolerance. This advantage has been documented time after time in the recommendations which are independent trials, and is regularly confirmed by our customers.

4turf® varieties rapidly develop strong roots. Grass plants upper root mass builds easily and often in excess, while the lower root mass allows for better exploitation of resources and improves the plant’s performance in stressful conditions. The benefits are two-fold:

  • Reduced inputs, which saves money and lowers your environmental impact
  • Improved value in the form of extended playing hours from the same input

High disease-tolerance

Another outcome of 4turf®‘s doubled chromosome count is increased disease-tolerance. In particular, every single 4turf® variety has a high resistance to red thread disease. Red thread is one of the few diseases against which breeding has failed to make much progress. 4turf® varieties typically score 1 or 2 points higher than diploids for red-thread resistance.

4turf® varieties also exhibit a high tolerance to crown rust disease and improved tolerance to both grey and pink snow moulds. This partly explains why 4turf® has such good winter hardiness.

Disease-tolerance makes sound management and financial sense. It extends the life of an investment in turf, it reduces the need for nitrogen or fungicides, and it ensures that the turf area is available for play. Disease-tolerance also helps to keep the turf looking good throughout the year.

For all these reasons 4turf® has performed well across the Scanturf trial network. In the stressful Nordic climate, 4turf® reveals its fundamental strength.

An excellent team player in mixtures

4turf® varieties make excellent mixture components. The explanation partly lies in the spatial arrangement of the above-ground plant parts. The cells and organs of a 4turf® tetraploid plant are bigger, stronger and arranged in fewer shoots. This simpler above-ground structure boosts stress-tolerance and creates room for other mixture components to flourish. They benefit from better air and light penetration, a feature that’s especially evident in mixtures containing tall fescue and 4turf®.

4turf® varieties for European climates

DOUBLE is the most widely tested 4turf® variety, earning itself a German listing for its excellent tolerance to red thread.

TETRAGREEN is complementary to DOUBLE.

TETRADRY keeps your turf looking greener for longer during periods of drought.

TETRADARK is popular for its wonderfully dark green appearance, a colour that’s similar to many tall fescues, diploid ryegrasses and Poa pratensis.

TETRASTAR is a hard-weather survivor, chosen for its winter colour and longevity.

FABIAN is another option for winter survival and colour; it performs so well, it’s the only perennial ryegrass recommended for turf grass in Finland.

TETRAGAME is the latest addition to the 4turf® family, bringing improved wear-tolerance to the range.