Indian Knotgrass

Names and Synonyms

Common Names

• Indian Knotgrass

Scientific Names

Accepted name

Regional and Traditional Names

Sources: Wikidata, Catalogue of Life

Taxonomical Classification

This plant belongs to the kingdom Plantae and the phylum Streptophyta, falling under the class Equisetopsida and subclass Magnoliidae. Within the order Caryophyllales, it is classified under the family Polygonaceae. Finally, it is identified by the genus Polygonum.

Sources: The World Checklist of Vascular Plants (WCVP)

Distribution

This plant exhibits a diverse range of habitats across the European continent and parts of Northern Asia. In Northern Europe, its presence can be identified within the borders of Great Britain. Moving toward the south, it is found throughout Southwestern Europe, specifically in France. Its distribution extends into Southeastern Europe in Bulgaria and reaches the Baltic States in Eastern Europe. Finally, the species reaches into the Siberian region, specifically located in the Altay mountains.

Sources: The World Checklist of Vascular Plants (WCVP)

Botanical Identification

Ecology

The ecology of Polygonum cognatum is characterized by its specialized adaptation to high-altitude environments, primarily thriving within mountainous terrains and stony places. This species occupies a significant altitudinal gradient, with its distribution spanning from a minimum elevation of 1,000 m AMSL to a maximum peak of 4,700 m AMSL. Throughout its range, the plant maintains a mean elevation of approximately 3,300 m AMSL, indicating a strong preference for alpine or subalpine ecological niches where rocky substrates provide its primary habitat.

Elevational range max:

4700 m AMSL

Elevational range mean:

3300 m AMSL

Elevational range min:

1000 m AMSL

Habitat :

mountains, stony places

Life history

The life history of Polygonum cognatum is characterized by its status as a perennial organism, allowing it to persist through multiple growing seasons. As a perennial, the plant establishes a robust presence in its habitat, often relying on underground structures to survive periods of dormancy before re-emerging to complete its reproductive cycle. Its developmental trajectory involves a continuous cycle of vegetative growth and seasonal flowering, which enables it to maintain long-term survival and colonize stable environments. This perennial nature ensures that the plant can accumulate resources over several years, contributing to its overall resilience and ability to sustain populations within its ecological niche.

Lifecycle :

perennial

Morphology

The morphology of Polygonum cognatum is characterized by its growth form as a non-woody herb, functioning as a small-statured forb. This species exhibits a self-supporting habit rather than being a climber and operates as an independent organism without parasitic tendencies. In terms of its physical dimensions, the plant maintains a diminutive stature, with a height ranging from a minimum of 0.05 m to a maximum of 0.13 m. Regarding its ecological positioning and habitat preference, the plant demonstrates versatility across aquatic, semiaquatic, and terrestrial environments.

Aquatic :

terrestrial

Climber :

self-supporting

Growth form :

herb

Parasite :

independent

Plant height max:

0.13 m

Plant height min:

0.05 m

Woodiness :

non-woody

Physiology

The physiology of Polygonum cognatum is characterized by specific morphological dimensions of its foliage that facilitate its metabolic processes and environmental interactions. The leaf architecture exhibits significant variability in size, with leaf lengths ranging from a minimum of 1 cm to a maximum of 2 cm, maintaining a mean length of approximately 1.5 cm. Complementing this longitudinal variation, the leaf width fluctuates between a minimum of 0.5 cm and a maximum of 1.3 cm. These precise dimensions in leaf surface area play a critical role in the plant's ability to manage gas exchange and light absorption, optimizing its photosynthetic efficiency within its ecological niche.

Leaf length max:

2 cm

Leaf length mean:

1.5 cm

Leaf length min:

1 cm

Leaf width max:

1.3 cm

Leaf width min:

0.5 cm

Reproduction

The reproduction of Polygonum cognatum is characterized by a specific seasonal flowering period that occurs during the height of summer. The flowering process typically begins in July and continues through the month of August. This relatively concise reproductive window ensures that the plant allocates its energy toward pollination and seed development during these peak months.

Flowering time :

Jul

Flowering time :

Aug

Sources: Global Inventory of Floras and Traits (GIFT)

Chemicals

Polygonum cognatum has 6 reported phytochemicals identified across 0 scientific publications and several other databases. The most consistently reported chemicals include Apigenin 7-O-glucoside, CHLOROGENIC ACID, RUTIN, kaempferol, luteolin-4'-o-glucoside.

Apigenin 7-O-glucoside

1. ChemistryOpen

CHLOROGENIC ACID

1. ChemistryOpen

RUTIN

1. ChemistryOpen

kaempferol

1. ChemistryOpen

luteolin-4'-o-glucoside

1. ChemistryOpen

quercetin

1. ChemistryOpen

Activities

Polygonum cognatum has 5 reported activities identified across 0 scientific publications and several other databases. The most consistently reported activities include Antioxidant, Antidiabetic, Antibacterial, Antimicrobial, Antiproliferative.

Antioxidant

1. Toxicology reports
2. Food technology and biotechnology
3. Biomedical chromatography : BMC

Antidiabetic

1. ChemistryOpen
2. Biomedical chromatography : BMC

Antibacterial

1. Food technology and biotechnology

Antimicrobial

1. Toxicology reports

Antiproliferative

1. Food technology and biotechnology

Preparations

Polygonum cognatum has 2 reported preparations identified across 0 scientific publications and several other databases. The most consistently reported preparations include aqueous ethanol by maceration method, ethanol extract.

Aqueous ethanol by maceration method

1. Toxicology reports

Ethanol extract

1. ChemistryOpen