''Tecticornia pergranulata'' (commonly known as the blackseed glasswort or blackseed samphire) is a succulent halophytic plant species in the family Chenopodiaceae, native to

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

. This plant is commonly tested in labs involving its

C3 photosynthesis carbon fixation is the most common of three metabolic pathways for carbon fixation in photosynthesis, along with and CAM. This process converts carbon dioxide and ribulose bisphosphate (RuBP, a 5-carbon sugar) into two molecules of 3-phospho ...

and its unique resistance to salinity and adversity.

Background

''Tecticornia pergranulata'' is a species of small erect sub-shrubs with articulate, succulent stems that grow around 1 meter in height. They also contain swollen branches with small leaf lobes and are mostly located on the boundaries of salt lakes and salty swamps all across southern Australia. They are most well known for their ability to adapt to high salinity levels and flooding.

Adaptations

When dealing with floods, this species has a unique method it uses to survive. Through research done by Sarah M Rich, Martha Ludwig, and Timothy Colmer, it was discovered that photosynthesis that takes place within ''Tecticornia pergranulata'' roots allows this species to survive through intense flooding. Larger ''Tecticornia pergranulata'' plants grow an extensive system of adventitious roots from their woody basal stem regions. Smaller plants do not form aquatic roots, but do grow adventitious roots within the soil. The aquatic roots grown by the larger plants exhibit two distinctive growth forms differing in color and length.

Types of roots

The most abundant roots that are grown are exclusively aquatic. These roots float in the water column and grow less than a millimeter in diameter. They are mostly superficially pink but can also contain a brownish green color especially found in the basal region. This type of root is also known as the aquatic root. The second type of root grown is superficially greenish brown and is thicker than aquatic roots. These roots range between 1 and 3 millimeters and grow through the water column into the surface soil. This type of root is also known as the semi-aquatic root.

Survival

The photosynthetic process that occurs in this species roots has the potential to supply oxygen to the rest of the plant while facing a flooded habitat. The cortical cells of the aquatic and semi aquatic roots contain photosynthetic chloroplasts. These chloroplasts produce specific responses to variation in carbon dioxide and light availability under water. They also contain proteins involved in the photosynthetic production of oxygen and

carbon fixation Biological carbon fixation or сarbon assimilation is the process by which inorganic carbon (particularly in the form of carbon dioxide) is converted to organic compounds by living organisms. The compounds are then used to store energy and as ...

. Unlike the sedimentary roots in this species, the aquatic roots get access to oxygen from the water column and can produce it internally. When both the semi aquatic and aquatic roots are submerged in water, photosynthesis occurs supplying oxygen for the plant.

Other classifications and uses

''Tecticornia pergranulata'' is also part of a separate group called the

Glasswort The glassworts are various succulent, annual halophytic plants, that is, plants that thrive in saline environments, such as seacoasts and salt marshes. The original English glasswort plants belong to the genus ''Salicornia'', but today the glass ...

s, the ashes of which yield soda ash, an important ingredient for glass and soap making.

Subspecies

''Tecticornia'' subspecies include: *subspecies ''elongata'' *subspecies ''divaricata'' *subspecies ''pergranulata''Datson, Bindy (2002) ''Samphires in Western Australia'': page 72-75

References

{{Taxonbar, from=Q7692817 pergranulata Caryophyllales of Australia Flora of New South Wales Flora of the Northern Territory Flora of Queensland Flora of South Australia Flora of Victoria (Australia) Eudicots of Western Australia Halophytes Barilla plants Taxa named by John McConnell Black