Ecotype

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ecotype

[′ek·ə‚tīp]
(ecology)
A subunit, race, or variety of a plant ecospecies that is restricted to one habitat; equivalent to a taxonomic subspecies.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Ecotype

 

a group of similar populations within one and the same plant species that are adapted to certain climatic, edaphic, or cenotic conditions and that have developed, under these conditions, hereditary morphological, physiological, biochemical, and other features. Thus, an ecotype is isolated with respect to distribution; genotypically it is an intraspecific subdivision, which distinguishes it from a biotype.

The term “ecotype” was introduced in the 1920’s by the Swedish scientist G. Turesson. Different plants have different numbers of ecotypes. The ecotypic composition of a species becomes more varied as its geographic range and ecological amplitude increase. For example, 36 ecotypes have been distinguished in the pine Pinus silvestris and 27 in the spruce Picea abies. Ecotypic polymorphism is most clearly manifested at the center of speciation and morphogenesis. In the medic Medicago falcata, for example, there are many ecotypes in the Caucasus and only a few in the northern USSR. Parallel ecotypic differentiation is observed in many species. Thus, the wormwood Artemisia campestris, sheep sorrel (Rumex acetosella), and Silene uniflora, which grow in bright, dry habitats where there are strong winds, develop eco-types with procumbent stems.

Three main groups of ecotypes are distinguished: climatic, edaphic, and biotypic. Climatic, or geographic, ecotypes occupy a separate part of the area of distribution of a species and originated under the influence of specific climatic conditions; for example, in the awnless brome (Bromus inermis), the southern eco-type differs from the northern one by its nanism, narrow rough leaves, and wax coating. Edaphic ecotypes develop under the influence of soil and ground conditions, such as the pine ecotype on the chalky outcrops of the Don River, which has even been described as the independent species Pinus cretácea. Biotypic, or cenotic, ecotypes appear and develop mainly under the influence of plants together with which the given species form plant communities, for example, the field and forest ecotypes of the cocksfoot (Dactylis glomerata) and the forest and dune ecotypes of the narrow-leaved hawkweed (Hieracium umbellatum).

The development of an ecotype is a lengthy process. If an ecotype has progressive characteristics, which permit it to extend the range of the species, it may give rise to a new species, and consequently an ecotype is one of the stages in the process of specia-tion.

REFERENCES

Sinskaia, E. N. Dinamika vida. Moscow-Leningrad, 1948.
Zavadskii, K. M. Uchenie o vide. Leningrad, 1961.
Korchagin, A. A. “Vnutrividovoi (populiatsionnyi) sostav rastitel’nykh soobshchestv i metody ego izucheniia.” In the book Polevaia geobotanika, vol. 3. Moscow-Leningrad, 1964.

KH. KH. TRASS

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
crispata populations, but they have never been found in clarki ecotypes, which could mean that they are cryptic reef species.
Moisture contents: Dry seeds were ground and moisture contents were determined by taking 2g sample of each ecotype and drying in the hot air oven provided with openings for ventilation.
Indigenous chicken from the 3 cluster ecotypes (Kakamega, Taita and Narok) were reared under intensive units at INCIP Egerton University, Kenya.
In the Mimulus guttatus complex, there is evidence for inviability in hybrids between metal-tolerant and intolerant parents (Gardner & MacNair, 2000), although such post-zygotic isolation is not a factor between coastal and inland ecotypes of the same taxon (Lowry et al., 2008).
Song et al., "Quality variation and ecotype division of Panax quinquefolium in China," Acta Pharmaceutica Sinica, vol.
Wheeler, Cann, and Mackie (2011), analyzing the genomic fingerprinting and serotypes of Salmonella isolated from marine and land iguanas of two islands (Santa Fe and Plaza Sur) located in Galapagos, observed a low similarity in the ecotypes of Salmonella present in the islands.
As criteria for inclusion in the database, the studies had to have been conducted in Rio Grande do Sul with ecotypes and/or hybrids of the genus Paspalum in plots, free from animal grazing for two agricultural years and total dry mass production (TDMP), leaf dry mass production (LDMP), and stem dry mass production (SDMP) had to be determined by means of cuts and expressed as kg of DM per hectare per year (kg DM [ha.sup.-1] [year.sup.-1]).
avenae that were obtained from different origins revealed the existence of ecotypes that differed in their hatching cycles, which is a result of the induction or suppression of dormancy (diapause) by different temperature conditions [19].
For identification of different ecotypes, the primers designed should meet two basic requirements: first is high success rate of PCR amplification and the second is high PCR products polymorphism to permit different ecotypes to be distinguished.
Due to the significant impact of rice production on agricultural systems, livelihoods, and food security in Bangladesh, there is a critical need to understand the spatiotemporal variability of rice agriculture and the spatially variable effects of climate change on rice yield for different ecotypes. Although the scientific and policy recommendations have already covered crop agriculture changes due to climate change [15], there is still an urgent need to provide additional policy suggestions by understanding regional differences in rice production due to spatially variable climate change effects [16, 17].
Keeping in view the global importance of Ficus palmata and its presence in Azad Kashmir as wild forests in abundance this research was conducted to study the medicinally important minerals in 25 selected Fig ecotypes from variable locations in Azad Jammu and Kashmir.