2,112 articles
Plant physiology
Plant physiology: the study of how plants function, covering photosynthesis, respiration, transpiration, xylem water transport, mineral nutrition, and stress responses; founded experimentally by Stephen Hales in 1727.
Plantaginaceae
Plantaginaceae, the plantain family (Lamiales), about 2,100 species in ~106 genera worldwide; expanded from polyphyletic Scrophulariaceae, 12 tribes, includes Plantago, Antirrhinum, Digitalis, Penstemon, Veronica.
Plantago
Plantago (plantains) is a cosmopolitan genus of about 246 accepted herb species in Plantaginaceae, with rosette leaves, spike inflorescences, and mucilaginous seeds; P. ovata yields psyllium husk, and P. lanceolata and P. major are global weeds and ecological models.
Plantago coronopus
Plantago coronopus, buck's-horn plantain, is a salt-tolerant Plantaginaceae herb native from Europe to Central Asia, with lobed rosette leaves eaten in salads, four subspecies, and introduced invasive populations in Korea, Australia, and the Americas.
Plantago lanceolata
Plantago lanceolata, ribwort plantain or narrowleaf plantain, a perennial Plantaginaceae herb native to temperate Eurasia and Macaronesia, naturalized worldwide; used as forage, food, and an EMA-listed traditional demulcent cough remedy.
Plantago major
Plantago major (broadleaf plantain, great plantain, white-man's-foot) is a Plantaginaceae herb native to temperate Eurasia and Africa, introduced worldwide, a lawn weed of compacted soil and an ancient wound-healing medicinal herb; distinct from psyllium (P. ovata).
Plantago ovata
Plantago ovata (psyllium, ispaghul, blond plantain) is a small Plantaginaceae herb native from the Mediterranean to India; its seed husk yields arabinoxylan gel fibre used as a bulk laxative, cholesterol-lowering supplement, and food thickener.
Platanaceae
Platanaceae, the plane-tree family (Platanus, sycamores), a monogeneric Proteales family of 10 deciduous tree species with peeling bark, globular flower heads, and 2n = 42, native mainly to temperate North America.
Platanus
Platanus (plane trees, sycamores) is the sole genus of Platanaceae, order Proteales, with 10 accepted species native from SE Europe to Indochina and E Canada to Guatemala; includes the London plane hybrid and faces canker stain disease.
Platanus occidentalis
Platanus occidentalis, American sycamore or buttonwood, a large deciduous tree of eastern North American bottomlands, parent of the London plane hybrid, with white exfoliating bark, singly borne fruit-balls, and no major IUCN threats.
Platanus orientalis
Platanus orientalis, the oriental plane, is a large deciduous tree native from southeast Europe to northern Iran, grown for millennia as a shade tree and parent of the London plane.
Platycodon grandiflorus
Platycodon grandiflorus, balloon flower (jiegeng, doraji, kikyo), sole species of its genus in Campanulaceae; East Asian perennial whose saponin-rich root is a traditional cough remedy, vegetable, and pharmacopoeial medicine.
Plectranthus
Plectranthus L'Hér., a mint-family (Lamiaceae) genus described in 1788, formerly held about 450 Old World tropical species; molecular phylogenetics split it in 2019, moving most species to Coleus and Equilabium, leaving 72 in Plectranthus sensu stricto.
Pleroma
Pleroma D.Don is a genus of about 157 to 181 species of Melastomataceae shrubs and trees native from Puerto Rico to southern tropical America, resurrected from Tibouchina in 2019 and including the ornamental glory bush Pleroma urvilleanum.
Plukenetia
Plukenetia (sacha inchi, Inca peanut) is a pantropical genus of 25 liana and vine species in Euphorbiaceae, defined by 4-carpellate fruits and basilaminar nectaries; P. volubilis seeds yield omega-3-rich oil.
Plukenetia volubilis
Plukenetia volubilis, or sacha inchi, Inca peanut, maní estrella: a Euphorbiaceae climbing shrub native to South Tropical America, grown for seeds rich in omega-3 oil and protein.
Plum
Plum: stone fruit of Prunus, chiefly European plum Prunus domestica (hexaploid, prune and jam uses) and Japanese plum Prunus salicina (diploid, fresh market); second stone fruit crop after peach, ~12 million tons.
Plumbaginaceae
Plumbaginaceae (leadwort family) is a Caryophyllales family of herbs and shrubs, sister to Polygonaceae, with 5-merous flowers, one ovule, salt-secreting glands, and genera such as Plumbago, Limonium, and Armeria.
Plumbago zeylanica
Plumbago zeylanica, commonly wild plumbago or Chitraka, is a scrambling shrub native to the tropics and subtropics, best known as a source of the bioactive compound plumbagin.
Plumeria
Plumeria, commonly known as frangipani or dok champa, is a genus of about 11 species of shrubs and small trees native to tropical America, grown for its fragrant, waxy flowers.
Plumeria rubra
Plumeria rubra, frangipani or temple tree (Apocynaceae), a deciduous tree native from Mexico to Venezuela, widely cultivated in the tropics for fragrant white, pink, yellow, or red flowers; IUCN least concern, medicinally used, low weed risk.
Podophyllum
Podophyllum (mayapples) is a Berberidaceae genus of 17 species from Afghanistan to China and eastern North America; P. hexandrum, the Himalayan mayapple, is the main podophyllotoxin source and is Endangered.
Pogostemon
Pogostemon, also called pogostemon or patchouli genus, is a Lamiaceae genus of about 80-95 herb and shrub species with disjunct African-Asian distribution; P. cablin yields patchouli essential oil, about 1,300 tonnes yearly.
Poinsettia
Poinsettia (Euphorbia pulcherrima, cuetlaxochitl, flor de Nochebuena), a Mexican shrub grown for red winter bracts; introduced to the U.S. by Joel Poinsett in 1828; short-day flowering; low toxicity.
Poison ivy
Poison ivy (Toxicodendron radicans, formerly Rhus radicans) is a North American Anacardiaceae vine or shrub whose urushiol oil causes allergic contact dermatitis in 10–50 million Americans yearly; three leaflets, cross-reacts with poison oak and sumac.
Polemoniaceae
Polemoniaceae, the phlox family, is an Ericales family of about 27 genera and 400 species of herbs and shrubs with 5-merous fused-petal flowers, centered in western North America; ornamentals include Phlox, Cobaea, Gilia, and Polemonium.
Polemonium caeruleum
Polemonium caeruleum, Jacob's-ladder or Greek valerian, is a perennial Polemoniaceae herb native from Europe to Japan and the Himalaya, with blue flowers, insect pollination, and five accepted subspecies.
Pollination
Pollination: transfer of pollen from anthers to stigmas by insects, other animals, wind, or water. Angiosperms are ancestrally insect pollinated; 87.5% of wild flowering plants and 35% of crop production depend on it.
Polyalthia
Polyalthia (Blume, 1830) is a genus of about 100 accepted species of trees and shrubs in Annonaceae, native from Madagascar to tropical Asia and NE Australia, polyphyletic historically, with medicinal clerodane diterpenoids and alkaloids.
Polygala
Polygala, known commonly as milkwort, is a large nearly cosmopolitan genus of flowering plants in the milkwort family, Polygalaceae, first published by Linnaeus in 1753.