CEPHALOTAXUS - patisa
Cephalotaxus Sieb. et Zucc. (Cephalotaxaceae) "Zimzeleno, dvodomno, rijetko jednodomno drveće ili grmovi. Grane pršljenasto smještene; mladi izbojci zeleni; pupovi jajoliki, pokriveni većim brojem trajnih ljusaka koje su poredane poput crijepa na krovu; igličasto lišće većinom raščešljano, s gornje strane s izrazitom srednjom žilom i s donje sa 2 široke plavkaste pruge puči; muški cvjetovi u glavičastim cvatovima do 1 cm debelim, u pazušcu iglica; ženski na najmlađim izbojcima 1-3 zajedno obavijeni ljuskavim listićima; "plod" velik poput koštunice, eliptičnog oblika, 2-3 cm dug, posve u mesnatom ovoju, koji je zelen do crvenkast; u "plodu" 1-2 sjemenke koje sazrijevaju u drugoj godini; broj kromosoma n = 12. Prema Sax i Saxu (1933.) Cephalotaxus, čini se, ima najveće kromosome među koniferama koje su oni izučavali. Broj kotiledona 2. Rod obuhvaća 8 vrsta, koje rastu u istočnoj Aziji." (M. Vidaković: "Četinjače", Zagreb 1982. str. 139-141) U međuvremenu pronađene su još neke vrste. Svaka vrsta ima više formi, varieteta i kultivara.
Osnovne vrste (prema http://en.wikipedia.org/wiki/Cephalotaxus) :
Cephalotaxus fortunei
Cephalotaxus griffithii
Cephalotaxus hainanensis
Cephalotaxus harringtonia
Cephalotaxus koreana
Cephalotaxus lanceolata
Cephalotaxus latifolia
Cephalotaxus mannii
Cephalotaxus oliveri
Cephalotaxus sinensis
Cephalotaxus wilsoniana
"Cephalotaxus
Common Names
Plum yew (Vidakovic 1991), Chinese: san jian shan shu (Fu et al. (1999)).
Taxonomic notes
It is here treated as the sole genus in the family Cephalotaxaceae, although several authors have also placed Amentotaxus (Taxaceae) in the family, and originally Cephalotaxus was placed in the Taxaceae as well. However, detailed embryological studies by Singh (1961) have shown that Cephalotaxus development differs strongly from all genera in the Taxaceae save Amentotaxus, which exhibits some intermediate characters. Nonetheless, the two families do resemble each other closely in vegetative characters including general foliar morphology and growth habit. As many as 12 species have been recognized, and the genus is badly in need of taxonomic revision. This treatment follows that of Tripp (1995), the most recent survey of the genus, and of Fu et al. (1999), which provides the only detailed information available in English for a number of Chinese species. Differences between the two treatments are noted as they occur. Tripp does not attempt a taxonomic study and notes that most key characters used to discriminate species are gradational, so that in many cases a knowledge of a specimen's provenance is necessary to confidently identify it to species. Indeed, as with Taxus, it is possible to make a good case that only one species exists (at least on the Asian mainland), with all other variations attributable to geoclimatic variation (Tripp 1995).
Description
Evergreen dioecious, rarely monoecious trees or shrubs. Branches opposite or whorled. Buds ovate, covered with numerous persistent imbricate scales. Leaves spirally arranged on terminal branchlets, appearing 2-ranked on lateral branchlets, needle-like, usually pectinate with a conspicuous midrib on the upper surface and 2 broad bluish stomata bands below. Male strobili are axillary, subglobose inflorescences up to 1 cm thick, sporophylls having 3-5 pollen sacs; pollen grains winged. Female cones borne on the youngest shoots, 1-3 together covered with scales, cones pendant, drupe-like, elliptic, 2-3 cm long, with a leathery, fleshy outer covering, green to reddish, containing 1-2 wingless seeds ripening the second season. Cotyledons 2. Chromosomes n = 12, among the largest of all conifer chromosomes (Silba 1986, Vidakovic 1991).
Fu et al. (1999) provide a key to the Chinese species; as it is available online, it is not reproduced here.
Range
Korea, China, Japan, Burma, Laos, Vietnam and India (Vidakovic 1991, Tripp 1995). Its center of distribution is in China, which holds portions of the native range of seven species. All species are highly shade tolerant, typically growing as understory trees or shrubs in humid temperate to subtropical broadleaf forests, and are typically uncommon within their ranges. A few species can tolerate cold temperate climates (USDA Zone 5 or 6), but none can tolerate aridity, and most can be damaged by exposure to full sun. They seem to be highly browse-resistant due to unpalatability. There is some concern that they suffer from poor regeneration due to a slow reproductive cycle (about two growing seasons for both male and female full development), dioecious habit, slow growth, long distances between individual plants, and seed predation by birds and mammals (although such predation is probably the main agent of seed dispersal). All species are threatened or endangered in their native range, primarily due to habitat loss (Tripp 1995).
Big Tree
See C. harringtonia.
Oldest
Dendrochronology
Ethnobotany
Many species are locally used for timber or firewood, and some (e.g., C. koreana) have been commercially exploited for timber. It has been used medicinally by native peoples, for instance by extraction of a seed oil in India. However, it has also been found to contain, like certain members of Taxus, anticancer alkaloids with names like cephalotaxine and harringtonine. This has led to exploitation for the purposes of extracting the anticancer compounds. Such exploitation threatens the survival of several species, but there is reason to hope that this can be avoided (as it was with Taxus) by synthesizing the compounds (Tripp 1995).
Observations
The species with the widest native ranges and greatest cold tolerance, C. fortunei, C. harringtonia, C. koreana and C. sinensis, can be readily found in botanical gardens and arboreta throughout the cold-temperate West. However, other species (C. griffithii, C. mannii) are not represented in any U.S. or U.K. gardens and must be seen in their rapidly-vanishing native habitats.
Remarks
The name is derived from the Greek kephale, meaning "head", and taxus, referring to the head-like shape of the staminate flowers in yew (Vidakovic 1991).
Philipp Franz von Siebold sent the first Cephalotaxus to Europe from Japan, in about 1829 (Tripp 1995).
The fossil record includes Jurassic specimens in Greenland, and Europe and NW North America during the Miocene and Pliocene (Tripp 1995).
Citations
Singh, H. 1961. The life history and systematic position of Cephalotaxus drupaceae Sieb. et Zucc. Phytomorphology 11:153-197." (Izvor: http://www.conifers.org/ce/ce/harringtonia.htm - autor Christopher J. Earle)
PREGLED PREMA http://www.ubio.org
(Izvor: http://www.conifers.org/ce/ce/har2.jpg)
(Izvor: http://www.conifers.org/ce/ce/1.jpg)
(Izvor: http://www.conifers.org/ce/ce/har5.jpg)
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