Astragalus nitidiflorus

Astragalus nitidiflorus is a species of legume in the family Fabaceae. It is endemic to Cartagena, southeast of Spain. It was refound after about 100 years of extinction and "the reappearance of this species has awakened the interest of environmental managers because the reasons for its critical situation are unknown". In 2004, a group of 46 specimens were discovered in a protected area between Cartagena and Mazarrón and plans for the conservation of this species have been implemented. ISSR markers helped to find that Astragalus nitidiflorus has a low genetic diversity. "This species grows in shallow soil from metamorphic and volcanic rocks in between mountain and cultivated areas".

Astragalus nitidiflorus is arranged in five spatially separated populations with about two thousand specimens. To increase this plants population size a natural regeneration has to occur. Early in 2005 demographic studies about Astragalus nitidiflores identified roughly 69 adult plants".

Its natural habitat is Mediterranean-type shrubby vegetation. This plant was first described in 1909, and was believed to be extinct.

Most of the individuals are preserved in a protected area called "Cabezos del Pericón", a Site of Community Importance included in the Natura 2000 ecological network.

Description
Astragalus nitidiflorus is endemic to the province of Murcia (southern Spain), where it forms the only known metapopulation worldwide. It is classified as Extinct in accordance with IUCN (2006) criteria.

Etymology
Nitidiflorus: Latin epithet meaning "bright with flowers".

Biology
The life cycle of A. nitidiflorus begins with seeds, which germinate in autumn and winter. In summer, leaves and stems die and only a few buds remain at the base of the stem at ground level. After the autumn rains, the dormant buds of the P1 plants that have survived the summer sprout and begin a second stage of growth.

A. nitidiflorus is a short-lived legume that colonizes old fields on volcanic soils. Most seeds and fruits were distributed in the soil surface layer (Table S1), and, except for 2011, most seeds were found inside fruits. This is explained by the type of fruit of A. nitidiflorus, an indehiscent and hard legume that prevents rapid release of seeds, which remain some years inside the fruit. Moreover, the considerable size of these fruits (ca. 1.9 cm 0.8 cm) hampers their burial, and nearly 100% them were on the soil surface.

"The life cycle of this species is very weak due to its low germination and limited adult species Extreme climate conditions can lead to a decrease in population.".

Habitat and cultivation
The seed bank is poor and very sensitive to changes in population size. The indehiscent fruit determines seed distribution in the soil around its mother plants. "A. nitidiflorus is able to form a short-term persistent soil seed bank". The seeding process happens in the summer months when there is a surplus water supply.

Beneficial uses
Not only with the Astragalus nitidiflorus, but most of the Astragalus plants have a plethora uses. Ranging from medicinal purposes, like helping treat the common cold or allergies, to feeding plants because of its good animal nutrition or the roots being good for controlling erosion.

Threats to species
"Natural regeneration is not expected for patches where the species disappeared few years ago".

Conservation
After the reappearance of this plant, the regional government of Murcia has declared this species as endangered. The known populations are under the protection of LIC of losCabezos Pericón spaces and the natural park of Sierra de la Muela, Cabo Tiñoso and Roldan. Some specimens also appear nearby the Black Cabeza de Tallante, that is close to an extinct Quaternary volcano, Cabezos Pericón. The population in the south-facing slopes part of Cabezos Pericón has been proposed as botany micorreserva with the name " Perez scrub the Netherlands '. The populations is also already protected as a Site of Community Importance (SCI ). One of the main goals in conserving this plant is preserving the genetic diversity of the endangered species Long-term survival and the evolution of species depends on the maintenance of genetic connectivity To maintain this plant’s population habitat destruction must be prevented. Attempts to save this plant along with many of the other Astragalus plants have been made through the use of Thidiazuron. This is because of the plant’s naturally slow seedling development and seed germination. A chemical which is a plant growth regulator which helps the plants be stronger and grow faster. This has been shown to help the plants grow even sterile seedlings but the sterile seedlings did not have healthy development. The regenerated shoots, however, had much more success and are even able to be transferred to another place. However, this chemical does have negative side-effects such as hyperhydricity and poor shoot development which can occur but do not always present itself.

Comparison with A. gines-lopezii
Astragalus gines-lopezii, A.nitidiflorus and A. devesae were described as the same species which was A. nitidiflorus. A. gines-lopezii is one of the phylogenetically closest species to A. nitidiflorus. A. nitidiflorus has a very high reproductive capacity on the production of flowers and seeds than A. gineslopezii. On the contrary, the proportion of flowers setting ripe fruits in A. gines-lopezii is higher compare to than in A. nitidiflorus.