Polygonaceae

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Fwd: Polygonaceae of India : 2 posts by 2 authors. Attachments (1).
Pl find attached herewith the pdf copy of my paper on Polygonaceae of India
appreciate the key and the pdf itself
Polygonaceae of India : 3 posts by 3 authors. Attachments (1)- Polyg India.pdf
Congratulation Sir!
Thanks for generating this important information on flora of India.
Hope complete Polygonaceae of India will be published soon, eagerly waiting for it.
Congratulations ...
That's a huge body of work and that too by a single person!
How many years of work does does the present paper represent?
 
The former complex genus has now been split into at least four major genera.
Here is a simpler key:
Flowers in axillary clusters (stamens inflated at base, inner larger; nectaries absent or inconspicuous) ... Polygonum
Flowers in Panicles, Spikes or Heads (All stamens equal, not inflated at base; nectaries present and conspicuous)
Flowers in clusters forming panicle or flat-topped corymb ... Koenigia
Flowers in well-defined spikes or heads
Plants rhizomatic perennials with prominent basal leaves; styles 3, free and elongate ... Bistorta
Plants annual, rarely perennials with rooting branches; leaves evenly distributed; style 1, bifid or trifid ... Persicaria
 
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:
FOC (pdf)

Thanks ... for a very informative introduction. It would surely help the members.
 
FAMILY : POLYGALACEAE ON INDIANTREEPIX

FAMILY : POLYGALACEAE

Milkwort family
Polygala (Latin) means much milk. Cattle feeding on these plants are supposed to give more milk.
There are 17 genera and 900-1000 species around the world. 50 % of the plants are in genus Polygala.

Vegetative characters:

It is a small cosmopolitan family of herbaceous plants, shrubs and small trees. Leaves are alternate, always simple, usually without stipules. Polygalas have Irregular flowers and superficially resembling Fabaceae.

Inflorescence and flowers:

Flowers are generally in spikes or racemes, each flower subtended by a bract and two bracteoles.

Sepals are 5 and unequal, two side sepals are often larger and coloured like petals. Uppermost sepal is keeled(Ridged in a way that resembles two connected petals or sepals. There are three petals united at base and the lower one boat shaped or saucer shaped -keelwith a fringed crest;enclosing 8 stamens and a pistil style. Stamens are often fused by their filaments into a split sheath. Ovary of two fused carpels, 2 chambered, each chamber one seeded;

Fruits and the seeds: Fruit is a capsule.

Examples: From Maharashtra

1. Leaves amplexicaul; flowers in spike; stamens 4-5; capsule toothed… Salomonia

1. Leaves not as above; flowers in racemes; stamens 8 capsule entire.… Polygala

2. Shrubs… P. arillata

2. Herbs

3. Flowers Pink…P. bulbothrix

P.irregularis

P.persicarifolia

3. Flowers yellow

P. furcata

… P.erioptera

… P.elongata

… P arvensis.

… P. Linarifolia


 

Our next episode will cover family Polygonaceae from May 1 to 14, 2014. Dr. Ritesh Kumar Choudhary who is a very well known expert on the group has kindly consented to coordinate the fortnight. Members are requested to take full advantage of his expertise and upload both identified photographs for validation and also those meant for identification. Kindly follow the format for convenient documentaion.
Thanks a lot dear ... for introduction.
I also request members to upload clear photographs with much possible details specially those of flowers, ochrea, nuts, leaves etc. Keeping in mind the morphological variations found in Polygonum, Persicaria and other genera, these characters are very important for identification.
I hope people would find enough time to search their disc drives for Polygonaceae members in the coming weekend.
Thanks, ..., for coordinating Polygonaceae fortnight.
16 Genera already discussed in efloraofindia (on clicking them one can see the species under them): .......

 
All existing genera pages of Polygonaceae in efi has been updated.
Pl. see: ...................
Hope this helps a bit during Polygonace​ae Fortnight.
Thank you very much ... for all your efforts... Surely this will help a lot...
 
PLANT TAXONOMY 2E By SHARMA - 2011- Details of Polygonaceae family
 
polygonaceae : 5 posts by 3 authors.
As per my observations, there are 121 species & 29 vars belonging to 12 genera (s.s.)
Thanks, ... Can you provide the complete list pl. ?
As per my observations, there are 121 species & 29 varieties belonging to 12 genera (s.s.) in India including the introduced ones which have become almost naturalised in India.
Yes. I shall send it soon.
  
 
 
 
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