Ribes

Taxonomy

Ribes is the single genus in the Saxifragales family Grossulariaceae. Although once included in the broader circumscription of Saxifragaceae sensu lato, it is now positioned as a sister group to Saxifragaceae sensu stricto.

Subdivision

First treated on a worldwide basis in 1907, the infrageneric classification has undergone many revisions, and even in the era of molecular phylogenetics there has been contradictory evidence. Although sometimes treated as two separate genera, Ribes and Grossularia (Berger 1924), the consensus has been to consider it as a single genus, divided into a number of subgenera, the main ones of which are subgenus Ribes (currants) and subgenus Grossularia (gooseberries), further subdivided into sections. Janczewski (1907) considered six subgenera and eleven sections. Berger's twelve subgenera based on two distinct genera (see Senters & Soltis (2003) Table 1) have subsequently been demoted to sections. Weigend (2007) elevated a number of sections to produce a taxonomy of seven subgenera; Ribes (sections Ribes, Heretiera, Berisia) Coreosma, Calobotrya (sections Calobotrya, Cerophyllum), Symphocalyx, Grossularioides, Grossularia, Parilla.

Taxonomy, according to Berger, modified by Sinnott (1985):

• Subgenus Ribes L. (currants) 8 sections
  • Section Berisia Spach (alpine currants)
  • Section Calobotrya (Spach) Jancz. (ornamental currants)
  • Section Coreosma (Spach) Jancz. (black currants)
  • Section Grossularioides ( Jancz.) Rehd. (spiny or Gooseberry-stemmed currants)
  • Section Heritiera Jancz. (dwarf or skunk currants)
  • Section Parilla Jancz. (Andine or South American currants)
  • Section Ribes L. (red currants)
  • Section Symphocalyx Berland. (golden currants)
• Subgenus Grossularia (Mill.) Pers. (Gooseberries) 4 sections
  • Section Grossularia (Mill.) Nutt.
  • Section Robsonia Berland.
  • Section Hesperia A.Berger
  • Section Lobbia A. Berger

Some authors continued to treat Hesperia and Lobbia as subgenera. Early molecular studies suggested that subgenus Grossularia was actually embedded within subgenus Ribes. Analysis of combined molecular datasets confirms subgenus Grossularia as a monophyletic group, with two main lineages, sect. Grossularia and another clade consisting of glabrous gooseberies, including Hesperia, Lobbia and Robsonia. Other monophyletic groups identified were Calobotrya, Parilla, Symphocalyx and Berisia. However, sections Ribes, Coreosma and Heritiera were not well supported. Consequently, there is insufficient resolution to justify further taxonomic revision.

Species

There are around 200 species of Ribes. Selected species include:

• Ribes alpinum
• Ribes aureum
• Ribes cereum
• Ribes divaricatum
• Ribes glandulosum
• Ribes hirtellum
• Ribes hudsonianum
• Ribes inerme
• Ribes lacustre
• Ribes laurifolium
• Ribes lobbii
• Ribes montigenum
• Ribes maximowiczii
• Ribes nevadense
• Ribes nigrum
• Ribes oxyacanthoides
• Ribes rubrum
• Ribes sanguineum
• Ribes speciosum
• Ribes triste
• Ribes uva-crispa

Distribution and habitat

Ribes is widely distributed through the Northern Hemisphere, and also extending south in the mountainous areas of South America. Species can be found in meadows or near streams.

Ecology

The majority of Ribes species are insect pollinated. Exceptions include R. sanguineum, R. malvaceum, and R. speciosum, which are humming-bird pollinated. After the flowers are pollinated and the fruits have matured, Ribes seeds are dispersed by birds and mammals, including elk, deer, cattle, and grizzly bears.

Currants are used as a food source by the larvae of some Lepidoptera species. Buff-tip moth caterpillars have shown strong preferences for Ribes species as host plants, especially R. alpinum and R. uva-crispa. The larvae of the moth species Archips argyrospilus, Papaiema nebris, Itame ribearia, and Nematocampa limbata are also associated with Ribes herbivory. Specifically winter moths and currant clearwing moths are known pests of currant species within agricultural settings.

Cultivation

The genus Ribes includes the edible currants: blackcurrant, redcurrant, and white currant, as well as the European gooseberry, Ribes uva-crispa, and several hybrid varieties. It should not be confused with the dried currants used in cakes and puddings, which are from the Zante currant, a small-fruited cultivar of the grape Vitis vinifera. Ribes gives its name to the popular blackcurrant cordial Ribena.

The genus also includes the group of ornamental plants collectively known as the flowering currants, for instance, R. sanguineum.

United States

There are restrictions on growing some Ribes species in some U.S. states, as they are the main alternate host for white pine blister rust.

White pine blister rust

Ribes species are a telial stage host for the white pine blister rust fungus Cronartium ribicola. Infected Ribes individuals display yellow spotting on their leaves that appear orange and raised on the abaxial leaf surface. Severely infected plants may even lose foliage. Infection occurs when wind-borne C. ribicola spores from Ribes individuals make contact with the needles of a five-needled pine. The fungus eventually spreads to the entirety of the tree. Pine infection usually occurs in late summer or early fall, as the moderate temperatures and high relative humidity create optimal conditions for C. ribicola spore germination.

Most species of wild and cultivated Ribes species have demonstrated R-gene and multigenetic resistance to white pine blister rust, which are the two dominant forms of genetic disease resistance in plants. The species R. nigrum and R. hudsonianum var. petiolare are particularly vulnerable to white pine blister rust infection.

Uses

A number of species produce edible berries, some of which are categorized as currants and gooseberries.

Blackfoot people used blackcurrant root (Ribes hudsonianum) for the treatment of kidney diseases and menstrual and menopausal problems. The Cree used the fruit of Ribes glandulosum as a fertility enhancer to assist women in becoming pregnant.

European immigrants who settled in North America in the 18th century typically made wine from both red and white currants.