Grazing versus mowing: productivity and forage quality of mixtures and cultivars of perennial ryegrass

Abstract

Perennial ryegrass (Lolium perenne L.) is an important grass species in temporary grasslands, where it is often sown as a mixture of multiple cultivars. In variety testing, however, candidate cultivars are evaluated as single-cultivar stands under standardised mechanical defoliation. In practice, swards are mown, grazed, or both, where grazing adds treading, selective defoliation, and heterogeneous nutrient return. Whether cultivar rankings obtained under mechanical defoliation also hold under grazing, and whether mixtures perform differently than their component cultivars, are unresolved. We compared six early-heading perennial ryegrass cultivars (three diploid, three tetraploid), and three 50:50 two-cultivar mixtures. The plots were grown under three defoliation treatments (i.e., regular cutting, simulated grazing, and grazing by dairy cows), over three years at two sites. Here we show that defoliation treatment and year affected dry matter yield (DMY) and forage quality stronger than the cultivar grown. The effect of ploidy depended on the defoliation treatment. Tetraploid cultivars had slightly higher DMY under regular cutting and simulated grazing and higher metabolisable energy throughout, whereas diploid cultivars had slightly higher DMY under grazing. Simulated grazing matched the forage quality of grazed swards, including cultivar ranking, but not the cultivar ranking for DMY. Forage quality rankings can therefore be assessed through simulated grazing, whereas DMY rankings of cultivars intended for grazing require evaluation under grazing. Diploid-tetraploid mixtures were intermediate in forage quality and, under grazing, slightly higher in DMY when compared to their individual components. Evaluating cultivars and mixtures under grazing would better reflect their relative performance in the field.

Genomic prediction of single cross families of perennial ryegrass under two nitrogen managements
Divino Rosa dos Santos Junior, Dario Fè, Ingo Lenk +4
The plant genome11 Oct 2026Peer-reviewedCC BY-NC-NDFull textGenetics & genomics Plant biologyEurope PMC
A constitutively active cortical nitrate-uptake cell state underlies nitrogen-use efficiency in perennial ryegrass
M. R. Kovi, P. Guevarra, S. Thu +15
bioRxiv12 Oct 2026PreprintCC BY-NC-NDFull textPlant biologybioRxiv
Genetic variation and trait selection in ryegrass (Lolium multiflorum Lam.) across dry and rainy seasons in Peru
Leidy G. Bobadilla, Miguel Castillo, Filipe Inácio Matias +5
Scientific Reports13 Oct 2026Peer-reviewedCC BY-NC-ND 4.0Full textPlant biologyCrossref
Different strategies, shared trajectories: biomass-allocation scaling during establishment and recovery from disturbance in perennial herbs
Jana Martínková, Jitka Klimešová, Adam Klimeš
Annals of Botany17 Aug 2026Peer-reviewedPublisher termsFull textEcologyPMC
Population genetic insights into biogeography and clonality of the perennial Ambrosia psilostachya DC. (Asteraceae) in the United States of America
Gerhard Karrer, Rea Hall, Valerie Le Corre +1
Flora3 Sep 2026Peer-reviewedCC BY 4.0Full textGenetics & genomicsHAL

Cite

BibTeX RIS

BibTeX

@misc{kach2026grazing,
  title = {{Grazing versus mowing: productivity and forage quality of mixtures and cultivars of perennial ryegrass}},
  author = {D. Käch and D. Suter and B. Studer and R. Kölliker and B. Reidy},
  howpublished = {bioRxiv},
  year = {2026},
  month = oct,
  doi = {10.64898/2026.10.15.759330},
  url = {https://www.biorxiv.org/content/10.64898/2026.10.15.759330v1},
  note = {CC BY},
}

RIS

TY  - UNPB
TI  - Grazing versus mowing: productivity and forage quality of mixtures and cultivars of perennial ryegrass
AU  - D. Käch
AU  - D. Suter
AU  - B. Studer
AU  - R. Kölliker
AU  - B. Reidy
PY  - 2026
DA  - 2026/10/15
PB  - bioRxiv
DO  - 10.64898/2026.10.15.759330
UR  - https://www.biorxiv.org/content/10.64898/2026.10.15.759330v1
AB  - Perennial ryegrass (Lolium perenne L.) is an important grass species in temporary grasslands, where it is often sown as a mixture of multiple cultivars. In variety testing, however, candidate cultivars are evaluated as single-cultivar stands under standardised mechanical defoliation. In practice, swards are mown, grazed, or both, where grazing adds treading, selective defoliation, and heterogeneous nutrient return. Whether cultivar rankings obtained under mechanical defoliation also hold under grazing, and whether mixtures perform differently than their component cultivars, are unresolved. We compared six early-heading perennial ryegrass cultivars (three diploid, three tetraploid), and three 50:50 two-cultivar mixtures. The plots were grown under three defoliation treatments (i.e., regular cutting, simulated grazing, and grazing by dairy cows), over three years at two sites. Here we show that defoliation treatment and year affected dry matter yield (DMY) and forage quality stronger than the cultivar grown. The effect of ploidy depended on the defoliation treatment. Tetraploid cultivars had slightly higher DMY under regular cutting and simulated grazing and higher metabolisable energy throughout, whereas diploid cultivars had slightly higher DMY under grazing. Simulated grazing matched the forage quality of grazed swards, including cultivar ranking, but not the cultivar ranking for DMY. Forage quality rankings can therefore be assessed through simulated grazing, whereas DMY rankings of cultivars intended for grazing require evaluation under grazing. Diploid-tetraploid mixtures were intermediate in forage quality and, under grazing, slightly higher in DMY when compared to their individual components. Evaluating cultivars and mixtures under grazing would better reflect their relative performance in the field.
ER  -

Abstract

Related

Cite