Ploidy is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Somatic cells, tissues, and individual organisms can be described according to the number of sets of chromosomes present : monoploid, diploid, triploid, tetraploid, pentaploid, hexaploid, heptaploid or septaploid, etc. The generic term polyploid is often used to describe cells with three or more chromosome sets.
Gossypium is a genus of flowering plants in the tribe Gossypieae of the mallow family, Malvaceae, from which cotton is harvested. It is native to tropical and subtropical regions of the Old and New Worlds. There are about 50 Gossypium species, making it the largest genus in the tribe Gossypieae, and new species continue to be discovered. The name of the genus is derived from the Arabic word goz, which refers to a soft substance.
Polyploidy is a condition in which the cells of an organism have more than two paired (homologous) sets of chromosomes. Most species whose cells have nuclei (eukaryotes) are diploid, meaning they have two sets of chromosomes—one set inherited from each parent. However, some organisms are polyploid, and polyploidy is especially common in plants. Most eukaryotes have diploid somatic cells, but produce haploid gametes by meiosis. A monoploid has only one set of chromosomes, and the term is usually only applied to cells or organisms that are normally haploid. Males of bees and other Hymenoptera, for example, are monoploid. Unlike animals, plants and multicellular algae have life cycles with two alternating multicellular generations. The gametophyte generation is haploid, and produces gametes by mitosis, the sporophyte generation is diploid and produces spores by meiosis.
Forage is a plant material eaten by grazing livestock. Historically, the term forage has meant only plants eaten by the animals directly as pasture, crop residue, or immature cereal crops, but it is also used more loosely to include similar plants cut for fodder and carried to the animals, especially as hay or silage. The term forage fish refers to small schooling fish that are preyed on by larger aquatic animals.
Acorus is a genus of monocot flowering plants. This genus was once placed within the family Araceae (aroids), but more recent classifications place it in its own family Acoraceae and order Acorales, of which it is the sole genus of the oldest surviving line of monocots. Some older studies indicated that it was placed in a lineage, that also includes aroids (Araceae), Tofieldiaceae, and several families of aquatic monocots. However, modern phylogenetic studies demonstrate that Acorus is sister to all other monocots. Common names include calamus and sweet flag.
The peony or paeony is a flowering plant in the genus Paeonia, the only genus in the family Paeoniaceae. Peonies are native to Asia, Europe and Western North America. Scientists differ on the number of species that can be distinguished, ranging from 25 to 40, although the current consensus is 33 known species. The relationships between the species need to be further clarified.
Dactylis is a genus of Eurasian and North African plants in the bluegrass subfamily within the grass family. Dactylis is native to North Africa, they are found throughout the world, and are an invasive species. They are known in English as cock's-foot or cocksfoot grasses, also sometimes as orchard grasses.
The American Elm cultivar Ulmus americana 'Jefferson' was cloned from a tree growing near a path in front of the Freer Gallery of Art, close to the Smithsonian Institution Building on the National Mall in Washington, D.C. The United States National Park Service, which had planted the tree during the 1930s, cloned it in 1993 after screening tests showed that it possessed an outstanding level of tolerance to Dutch elm disease (DED).
Psidium guajava, the common guava, yellow guava, or lemon guava, is an evergreen shrub or small tree native to the Caribbean, Central America and South America. It is easily pollinated by insects; when cultivated, it is pollinated mainly by the common honey bee, Apis mellifera.
Chelone is a genus of four species of perennial herbaceous plants native to eastern North America. They all have similarly shaped flowers, which vary in color from white to red, purple or pink. Chelone cuthbertii, C. glabra, and C. lyonii are diploid and C. obliqua is either tetraploid or hexaploid, depending on their slight differences in morphology and localities.
Asplenium trichomanes, the maidenhair spleenwort, is a small fern in the spleenwort genus Asplenium. It is a widespread and common species, occurring almost worldwide in a variety of rocky habitats. It is a variable fern with several subspecies.
Chloris gayana is a species of grass known by the common name Rhodes grass. It is native to Africa but it can be found throughout the tropical and subtropical world as a naturalized species.
Stylosanthes is a genus of flowering plants in the legume family, Fabaceae and contains numerous highly important pasture and forage species. It was recently assigned to the informal monophyletic Pterocarpus clade of the Dalbergieae. The common name pencilflower is sometimes used for plants in this genus.
Pellaea glabella is the smooth cliffbrake. For much of pteridological history, it was regarded as a reduced form or variety of Pellaea atropurpurea. P. glabella is known to exist in two cryptic species, one diploid and one tetraploid. The diploid reproduces sexually, while the tetraploid is normally apogamous. It is now known that the tetraploid form of the species is one of the parents of the original hybrid P. × atropurpurea that became the apogamous species.
Dichanthium annulatum is a species of grass. It is commonly used as a forage for livestock.
Digitaria didactyla is a species of grass known by the common names blue couch, Queensland blue couch, blue serangoon grass, green serangoon grass, blue stargrass, and petit gazon. It is native to Mauritius, Réunion, parts of mainland Africa, and Madagascar. It has been introduced widely outside its native range, mainly for use as a pasture and turf grass. It has naturalized in some regions.
Rosa kordesii, or Rosa × kordesii is a red type of rose that arose naturally from hybridization followed by chromosome doubling. A hybrid between R. rugosa and R. wichurana was created called Rosa 'Max Graf', but it was diploid and nearly sterile, producing flowers but no fruit. This rose produced a few viable seeds as a result of self-pollination, and the seedlings that resulted were tetraploid instead of diploid, i.e., the chromosomes of both pollen and egg cells had been naturally duplicated. The tetraploid seedlings are amphidiploids. A selection with double deep pink flowers and repeat bloom, also called 'K01 AgCan' was released by W. Kordes' Söhne in 1951.
Indigofera hirsuta, the hairy indigo or rough hairy indigo, is a species of flowering plant in the family Fabaceae. It is native to nearly all the world's tropics; South America, Africa, Madagascar, the Indian Subcontinent, southern China, southeast Asia, Malesia, Papuasia and Australia, and has been introduced to the Caribbean, the southeast United States, Mexico and Central America. It is used as a green manure and, to a minor extent, for forage.
Indigofera spicata, the creeping indigo or trailing indigo, is a species of flowering plant in the family Fabaceae. It is native to Sub‑Saharan Africa, Madagascar, Mauritius, Réunion, and Yemen, and has been introduced to the southeastern United States, various Caribbean islands, Brazil and other locations in Latin America, various Pacific islands, and New South Wales and Queensland in Australia. It was considered to be a promising forage plant, and then shown to be toxic to nearly all livestock, but it is possible that the experiments were conducted on the similar Indigofera hendecaphylla, leading to some confusion.
Stylosanthes guianensis, the stylo, is a species of flowering plant in the family Fabaceae. It is native to the New World Tropics and Subtropics, and has been introduced to Puerto Rico, the Windward Islands, Trinidad and Tobago, most of Sub‑Saharan Africa, Madagascar, Mauritius, Réunion, Rodrigues, the Indian Subcontinent, Sri Lanka, Thailand, southeast China, Hainan, Taiwan, New Guinea, Queensland, New Caledonia, and the Cook Islands. An important forage and fodder species, its palatability to livestock increases as the plant matures, making it an unusual, and valuable, deferred feed. It has high genetic diversity between and among its named varieties.
