''Hordeum brachyantherum'', known by the common name meadow barley, is a species of

barley Barley (''Hordeum vulgare''), a member of the grass family, is a major cereal grain grown in temperate climates globally. It was one of the first cultivated grains, particularly in Eurasia as early as 10,000 years ago. Globally 70% of barley pr ...

. It is native to western North America from

Alaska Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S., ...

to northern Mexico, coastal areas of easternmost Russia (Kamchatka), and a small area of coastal

Newfoundland Newfoundland and Labrador (; french: Terre-Neuve-et-Labrador; frequently abbreviated as NL) is the easternmost province of Canada, in the country's Atlantic region. The province comprises the island of Newfoundland and the continental region ...

. The

diploid Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Sets of chromosomes refer to the number of maternal and paternal chromosome copies, respectively ...

cytotype occurs only in

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

, throughout the state, while everywhere else plants are

tetraploid Polyploidy is a condition in which the cells of an organism have more than one pair of ( homologous) chromosomes. Most species whose cells have nuclei (eukaryotes) are diploid, meaning they have two sets of chromosomes, where each set contains ...

. This is a tufting perennial

bunchgrass Tussock grasses or bunch grasses are a group of grass species in the family Poaceae. They usually grow as singular plants in clumps, tufts, hummocks, or bunches, rather than forming a sod or lawn, in meadows, grasslands, and prairies. As perennial ...

approaching a meter in maximum height. It produces compact, narrow

inflorescence An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...

s 8 to 10 centimeters long and purplish in color. Like other barleys the spikelets come in triplets. It has two small, often sterile lateral spikelets on

pedicels In botany, a pedicel is a stem that attaches a single flower to the inflorescence. Such inflorescences are described as ''pedicellate''. Description Pedicel refers to a structure connecting a single flower to its inflorescence. In the absenc ...

and a larger, fertile central spikelet lacking a pedicel.

General information

''Hordeum brachyantherum'' belongs to grass family,

Poaceae Poaceae () or Gramineae () is a large and nearly ubiquitous family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos and the grasses of natural grassland and species cultivated in lawns an ...

, genus ''

Hordeum ''Hordeum'' is a genus of annual and perennial plants in the grass family. They are native throughout the temperate regions of Africa, Eurasia, and the Americas. One species, ''Hordeum vulgare'' (barley), has become of major commercial importan ...

''. There are two common cytotypes of ''Hordeum brachyantherum''. The diploid mainly grow in California, the tetraploid grow widely over the world.

Polyploid Polyploidy is a condition in which the cells of an organism have more than one pair of ( homologous) chromosomes. Most species whose cells have nuclei ( eukaryotes) are diploid, meaning they have two sets of chromosomes, where each set contain ...

y is very common in plants. Polyploidization plays an important role in plant evolution, it is commonly used in agriculture to develop novel phenotypes. Polyploidization also occurs naturally in plant populations. In 1980, a rare hexaploid form of ''Hordeum brachyantherum'' was discovered in California within the populations of diploid and tetraploid ''Hordeum brachyantherum''. It was hypothesized that this hexaploid form was evolved by outcrossing between diploid ''Hordeum marine'' and tetraploid ''Hordeum brachyantherum'' ssp. ''brachyantherum'' and followed by duplication of chromosome. Polyploidization may lead to speciation because the reproductive isolation may develop between hexaploid and either tetraploid or diploid due to the mistake of alignment during meiosis.

Homology

''Hordeum'' contains a gene called ''hordoindoline'' that involves grain hardness and antimicrobial activity. Since wheat contains a

homologous gene Sequence homology is the biological homology between DNA, RNA, or protein sequences, defined in terms of shared ancestry in the evolutionary history of life. Two segments of DNA can have shared ancestry because of three phenomena: either a spec ...

named ''puroindoline'', it was concluded that ''Hordeum'' and wheat shared a common ancestor during the evolutionary process. The novel variants of ''hordoindoline'' genes were found in ''Hordeum brachyantherum''. It was hypothesized that the novel genes arose due to the gene duplication during the early stage of the divergence of the genus ''Hordeum''. Some of the non-synonymous mutations are beneficial and show an overall improved antifungal activity. These non-synonymous mutations provide the material for evolution because natural selection can select for organisms who possess these mutations and alter the allele frequency over time.

Salinity

Natural selection can also act on salinity tolerance for many plants. High salinity may negatively impact germination success, plant growth, and survival. Thus, under evolutionary process including natural selection, some plants developed morphological and physiological adaptations to live in high salinity conditions. The effect of salinity on germination rate shows both inter-specific and intra-specific variation. Compared to other perennial plants such as ''

Agrostis stolonifera ''Agrostis stolonifera'' (creeping bentgrass, creeping bent, fiorin, spreading bent or carpet bentgrass) is a perennial grass species in the family Poaceae. Description ''Agrostis stolonifera'' is stoloniferous and may form mats or tufts. The ...

'', ''Hordeum brachyantherum'' is more tolerated under high salinity. The seedling lengths and root or shoot lengths show different responses to high salinity. The seedling lengths of ''Hordeum brachyantherum'' are more negatively affected by high salinity. The intra-specific variation in the ability to tolerate elevated salinity among populations of ''Hordeum brachyantherum'' may result from the genetic variation which underlines the basis of evolution of ''Hordeum brachyantherum''.

Ecology

One major function of perennial plants is to restore the land and ecosystem. ''Hordeum brachyantherum'' is used to restore the native perennial grasslands in California and to reduce the density of non-native annual plants. The perennial plants can rapidly recover the soil microbial biomass in the grasslands due to the carbon supply maintained by the perennial plants. The species diversity and composition is not affected by the restoration, however, the relative proportion of the native plant biomass increased in the restored perennial grassland.Potthoff M, Jackson LE, Steenwerth KL, Ramirez I, Stromberg MR, Rolston DE. (2005) Soil Biological and chemical properties in restored perennial grassland in California. ''Restoration Ecology'' 13(1):61-73.

References

External links

Jepson Manual TreatmentUSDA Plants ProfilePhoto gallery
{{Taxonbar, from=Q5903002 brachyantherum Bunchgrasses of North America Bunchgrasses of Asia