Excellent start Ritesh ji. Dr Satish Phadke
On 28 April 2014 12:11, Dr Pankaj Kumar <sahanipan...@gmail.com> wrote: > Nice writeup. Best of luck Ritesh. > Pankaj > > > On Friday, 25 April 2014 12:53:29 UTC+8, Ritesh Kumar Choudhary wrote: >> >> Family of the fortnight: POLYGONACEAE >> >> Distribution: The family includes approximately 46 genera and 1200 >> species (Mabberley, 2008) from the world and mostly distributed in north >> temperate regions. >> >> Two subfamilies Polygonoideae and Eriogonoideae are universally accepted >> based on the presence or absence of the ochrea (sometimes rudimentary in >> Eriogonoideae). >> >> >> All Indian genera belong to Polygonoideae, a subfamily of almost 790 >> species defined by the presence of ocreae, a monopodial branching pattern, >> and lack of involucre. >> >> The Eriogonoideae (ca. 330 species) are found only in the New World. (Li >> Anjen et al., 2003). >> >> Description: Members of Polygonaceae are either annual or perennial >> herbs, shrubs or trees. The leaves are simple, alternate, seldom opposite >> or whorled, usually entire and revolute, usually in spirals, petiolate to >> sessile. >> >> The presence of ochrea is the most distinguishing feature, but in the >> subfamily Eriogonoideae, it is either absent or reduced in size. >> >> Variation can be seen in the axillary or terminal inflorescence which is >> composed of simple or branched thyrsi panicle-, raceme- or spike-like in >> appearance which however, are formed of dichasia or helicoid cymes. >> >> The flowers are small, trimerous, hermaphrodite or unisexual with tepals >> 2-6, forming two whorls of 3 elements or one whorl of 5 elements with >> characteristic quincuncial aestivation. >> >> The number of stamens ranges from 2 to 9 or rarely more whereas the >> pollen character varies from tricolporate to pantoporate. The ovary is >> superior 2-4 carpellate (generally 3-carpellate) and unilocular whereas the >> fruits are an achene which is trigonous or lenticular. >> >> >> Taxonomic treatments: >> >> Recently, Sanchez et al. (2011) proposed a new taxonomic classification >> for Polygonoideae based on molecular data that includes five tribes: >> Calligoneae, Fagopyreae, Persicarieae, Polygoneae, and Rumiceae. >> >> Polygonum s.l. is the largest genus in Polygonaceae and a member of the >> core eudicots in the flowering plants (Judd et al. 2002). It is >> represented by about 230 species in the world and distributed mostly in N >> temperate regions (Li Anjen et al, 2003). The genus (commonly known as >> Knotweeds) has long been a taxonomic puzzle and is widely debated. >> >> The traditional method of classification has led to disagreement among >> taxonomists with regard to which species should be included in the genus >> *Polygonum >> *and which taxa should be elevated to their own genus due to the >> presence of at least one distinguishing characteristic. (Meisner, 1826, >> 1856, 1857; Bentham & Hooker, 1880; Dammer, 1892; Gross, 1913 a, 1913b; >> Jaretzky, 1925; Hedberg, 1946; Roberty & Vautier, 1964; Graham & Wood, >> 1965; Holub, 1971; Sojak, 1974; Haraldson, 1978; Tzvelev, 1987; Ronse >> Decraene & Akeroyd, 1988; Hassan, 1991, 1997; Hassan & Khan, 1992; Hong et >> al, 1998; Ronse Decraene et al., 2000). >> >> The biomolecular studies by Cuenound et al. (2002), Lamb Frye & Kron >> (2003), Kim et al. (2005), Kim & Donoghue (2008) and Sanchez and Kron >> (2008) have revealed that *Polygonum *s.l. is polyphyletic, and should >> be divided into several genera. The treatment of subfamily Polygonoideae by >> Haraldson (1978) Ronse Decraene (1988) have suggested species of *Polygonum >> *in the broad sense to be segregated into two separate tribes, >> Polygoneae and Persicarieae. >> >> Medicinal Value: >> Medicinal uses of 31 species belonging to 7 genera Viz. *Calligonium*, >> *Pteropyrum*, *Polygonum*, *Fagopyrum*, *Rheum*, *Oxyria* and *Rumex*, >> were recorded by Kirtikar & Basu (1980). >> >> Thirty four species of *Polygonum* (*s.l.*) have been reported for >> medicinal uses (Choudhary et al., 2011). >> >> Some useful references: >> http://www.ingentaconnect.com/content/iapt/tax/2011/ >> 00000060/00000001/art00013 >> http://flora.huh.harvard.edu/china/mss/volume05/Polygonaceae.pdf >> http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=10717 >> http://donoghuelab.yale.edu/sites/default/files/174_kim_systbot08_0.pdf >> http://lnmcp.mf.uni-lj.si/Fago/Fagopyrum/Fagopyrum/Each/ >> Fag(18)/Fag(18)-9.pdf >> http://archive.bsbi.org.uk/Wats5p177.pdf >> http://www.biology.sc.chula.ac.th/TNH/archives/v11_no1/21- >> 28%20Chorthip%20TNH%2011-1.pdf >> http://www.lifesciencesite.com/lsj/life1002/369_ >> B01505life_1002_2664_2670.pdf >> >> >> Regards, >> Ritesh. >> >> Note: Please write me separately for details of the references used in >> the text above. >> >> -- > You received this message because you are subscribed to the Google Groups > "efloraofindia" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to indiantreepix+unsubscr...@googlegroups.com. > To post to this group, send email to indiantreepix@googlegroups.com. > Visit this group at http://groups.google.com/group/indiantreepix. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "efloraofindia" group. To unsubscribe from this group and stop receiving emails from it, send an email to indiantreepix+unsubscr...@googlegroups.com. To post to this group, send email to indiantreepix@googlegroups.com. Visit this group at http://groups.google.com/group/indiantreepix. For more options, visit https://groups.google.com/d/optout.
