''Lolium'' is a genus of tufted grasses in the bluegrass subfamily (Pooideae). It is often called ryegrass, but this term is sometimes used to refer to grasses in other genera. They are characterized by bunch-like growth habits. ''Lolium'' is native to

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...

and northern

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

, as well as being cultivated and naturalized in

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

, the

Americas The Americas, sometimes collectively called America, are a landmass comprising the totality of North America and South America.''Webster's New World College Dictionary'', 2010 by Wiley Publishing, Inc., Cleveland, Ohio. When viewed as a sing ...

, and various oceanic islands. Ryegrasses are naturally diploid, with 2n=14, and are closely related to the fescues (''Festuca''). Ryegrass should not be confused with rye, which is a grain crop.

Species

the species of ''Lolium'' listed by

Plants of the World Online Plants of the World Online (POWO) is an online taxonomic database published by the Royal Botanic Gardens, Kew. History Following the Convention on Biological Diversity, the Royal Botanic Gardens in Kew launched Plants of the World Online i ...

include: ; Formerly included Several former ''Lolium'' species now regarded as part of other genera: '' Castellia'', '' Enteropogon'', '' × Festulolium'', '' Hainardia'', '' Lepturus'', '' Melica'', and '' Vulpia''. File:Perennial Ryegrass.jpg, Perennial ryegrass, used as winter lawn. File:Illustration Leymus arenarius and Lolium temulentum0.jpg, Poison darnel (''Lolium temulentum'')

Cultivation and uses

''Lolium'' contains some species which are important grasses for

lawn A lawn () is an area of soil-covered land planted with Poaceae, grasses and other durable plants such as clover lawn, clover which are maintained at a short height with a lawn mower (or sometimes grazing animals) and used for aesthetic an ...

s, and as pasture and for grazing and hay for

livestock Livestock are the Domestication, domesticated animals that are raised in an Agriculture, agricultural setting to provide labour and produce diversified products for consumption such as meat, Egg as food, eggs, milk, fur, leather, and wool. The t ...

, being a highly nutritious stock feed. Ryegrasses are also used in

soil Soil, also commonly referred to as earth, is a mixture of organic matter, minerals, gases, water, and organisms that together support the life of plants and soil organisms. Some scientific definitions distinguish dirt from ''soil'' by re ...

erosion Erosion is the action of surface processes (such as Surface runoff, water flow or wind) that removes soil, Rock (geology), rock, or dissolved material from one location on the Earth's crust#Crust, Earth's crust and then sediment transport, tran ...

control programs. It is the principal grazing grass in

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where some 10 million kilograms of certified seed are produced every year. There is a large range of

cultivar A cultivar is a kind of Horticulture, cultivated plant that people have selected for desired phenotypic trait, traits and which retains those traits when Plant propagation, propagated. Methods used to propagate cultivars include division, root a ...

s. The primary species found worldwide and used both for lawns and as a forage crop is perennial ryegrass (''Lolium perenne''). Like many cool-season grasses of the Poaceae, it harbors a symbiotic fungal endophyte, either '' Epichloë'' or its close relative '' Neotyphodium'', both of which are members of the fungal family Clavicipitaceae. Some species, particularly ''L. temulentum'', are

weed A weed is a plant considered undesirable in a particular situation, growing where it conflicts with human preferences, needs, or goals.Harlan, J. R., & deWet, J. M. (1965). Some thoughts about weeds. ''Economic botany'', ''19''(1), 16-24. Pla ...

s which can have a severe impact on the production of wheat and other crops. Annual ryegrass (''L. rigidum'') is one of the most serious and costly weeds of cropping systems in southern Australia, and herbicide resistance is a frequent problem. Ryegrass

pollen Pollen is a powdery substance produced by most types of flowers of seed plants for the purpose of sexual reproduction. It consists of pollen grains (highly reduced Gametophyte#Heterospory, microgametophytes), which produce male gametes (sperm ...

is also one of the major causes of

hay fever Allergic rhinitis, of which the seasonal type is called hay fever, is a type of rhinitis, inflammation in the nose that occurs when the immune system overreacts to allergens in the air. It is classified as a Allergy, type I hypersensitivity re ...

Tennis court A tennis court is the venue where the sport of tennis is played. It is a firm rectangular surface with a low net stretched across the centre. The same surface can be used to play both Types of tennis match, doubles and singles matches. A variet ...

s, including those at the

All England Lawn Tennis and Croquet Club The All England Lawn Tennis and Croquet Club (AELTC), also known as the All England Club, based at Church Road, Wimbledon, London, England, is a Gentlemen's club, private members' club. It is best known as the venue for the Wimbledon Championsh ...

, the venue for Wimbledon, are planted with ryegrass. Glyphosate-resistant ''Lolium'' has been reported from Mississippi in 2006.

References

{{Authority control Pooideae Poaceae genera Taxa named by Carl Linnaeus