User:Coralinepraz

Hippophae rhamnoides, (common name : sea buckthorn) is a deciduous, epinous shrub from the genus Hippophae. This plant originates from Europe and Asia and is nowadays cultivated for his berries. These berries are used for their medicinal, therapeutic and nutritious qualities.

Taxonomy
Hippophae rhamnoides is the Latin name for sea buckthorn. The genus Hippophae belongs to the family Elaeagnaceae. H. rhamnoides is the most widespread species of the genus Hippophae. This genus counts nine subspecies: carpatica, caucasia, gyantsensis, mongolica, sinensis, turkestanica, yunnanensis, rhamnoides and fluviatilis.

Description and Biology
Sea buckthorn is a fruitful shrub that can grow 2 to 4 meters high. It is a deciduous and dioecious species and normally spiny. The leaves are alternate, narrow and lanceolate. Their upper faces are silvery green. Sea buckthorn is a dioecious species. This means that the male and female flowers grow on different shrubs. The male inflorescence is built up of four to six flowers without petals. The female inflorescence consists normally of only one flower without petals and contains one ovary and one ovule. Male plants need to be planted near the female plants ones to allow the fecundation, this leads to the production of fruits. The fruits are oval or lightly roundish. They grow in compact grapes and their color varies from pale yellow to dark orange. They weight between 0.2 and 1 g. The sea buckthorn has a very developed root system that can maintain the soil on high slopes. The roots live in symbiosis with actinomycetes. This relationship permits to fix nitrogen from the air. They also transform insoluble organic and mineral matters from the soil to more soluble states. The rhizomes grow very fast and produce sockers and can so produce new colonies.

Origin and Distribution
Sea buckthorn is native from the temperate zones of Europe and Asia. It is spontaneous in Eurasia : China, Mongolia, Russia, Kazakhstan, Iran, Turkey, Latvia, Turkey, Romania, Poland, Germany, Switzerland, France, Netherland, Finland, Norway, Sweden, Great Britain and Denmark. Sea buckthorn also grows in North America (USA and Canada) and was imported by the Russian migrants at the beginning of the 20th century.

Cultivation
The domestication of sea buckthorn occurred a few decades ago and this because of its numerous qualities. The first International Symposium on sea buckthorn already took place in 1989 in Xi'an (China) and since then other European and International Symposium occurred.

Varieties and Cultivars
There is a high genetic variability in the nine subspecies of H. rhamnoides. This large genetic pool can be used in breeding programs and the desired characters can be selected. Some countries, such as Russia, China, Latvia, Finland and Germany have breeding programms for sea buckthorn and therefore most of the cultivars are from these countries. The breeding criteria are for example the presence of thorns, the resistance to cold, the yield, the taste of the fruits, the contents of nutritious substances or the resistance to pest.

Soil
Sea buckthorn grows better on soils with a pH between 6 and 7 because it is a favorable environment for the actinomycetes that colonize the roots.

Plantation
Sea buckthorn is normally planted (seedlings) or sowed in spring. Sea buckthorn needs an adequate level of nutrients to produce a good yield and fruits of good quality. It responds well to phosphorous. The yield depends on the exposition to light as sea buckthorn doesn't like shadow. Therefore it is important to plant shrubs with distances between them. Plants are normally planted with 1 to 1.5 meters in rows that have 3 to 6 meters between each other. The density of the plantations varies from 500 to 3300 plants per hectare.

Plant protection
Relatively few diseases and insects are important on sea buckthorn but the followings are reported:

The disease Verticillium wilt caused by Verticillium albo-atrum and Verticillium dahliae is widespread where sea buckthorn is cultivated. The disease appears on trees 5 to 8 years after plantation. The infected fruits mature prematurely, dry up and shrivel. Infected trees should be dug out and burned. For 3 to 5 years sea buckthorn should not be planted at the same place. Fusarium wilt is another important disease in sea buckthorn. Fusarium spp. seems to only attack rotting and dying plants. Infected branches should be cut and burned. There are also insects affecting sea buckthorn as aphids, thrips, two-spotted mites and earwigs. The gall tick, the leaf roller, the gypsy moth and the commashaped scale also cause damages to sea buckthorn.

The most damaging insect is the sea buckthorn fly. It penetrates the fruits and eats the flesh. The fruits are then unacceptable for use.

Weed control
Weed control is very important especially during the early growth stages. Sea buckthorn grows slower than weeds because it has a less vigorous root system. Weeds should be removed before planting and then controlled during the first 4 or 5 years. Mechanical and hand cultivation are both used for weed control. The cultivation should not be too deep not to damage the roots of sea buckthorn. (Does sea buckthorn have a fibrous root system? If so, you could include this information in this part)