Search Results

You are looking at 1 - 10 of 1,060 items for :

  • "diversity" x
  • Biology and Life Sciences x
  • All content x
Clear All

Fernández-González , M. ( 2011 ): Fungal diversity in honeys from northwest Spain and their relationship to the ecological origin of the product . – Grana 50 : 55 – 62 . http://dx.doi.org/10

Restricted access

endophytes in dicotyledonous neotropical trees: patterns of abundance and diversity . – Mycol. Res. 105 ( 12 ): 1502 – 1507 . https://doi.org/10.1017/S0953756201004956 Bae , H. , Sicher

Restricted access

Şahin, B. (2004): Species composition and diversity of epipelic algae in Çatal Lake (Şebinkarahisar-Giresun, Turkey). — Turk. J. Biol. 28 : 103–109. Şahin B. Species composition

Restricted access

endophyte of pioner grasses in a maritime sand dune. Trans. Br. Mycol. Soc. 72, 261–268. 42 Onguene, N-A. (2000): Diversity and dynamics of mycorrhizal associations in tropical rain

Restricted access

The genetic diversity of cultivated spelt (Triticum aestivum ssp. spelta) presently is narrow. Evaluation of germplasm collections of spelt on quality level supplemented with DNA analysis is, therefore, of great importance. This study was designed to help the evaluation process for the selection of new spelt varieties with a support of molecular characterization. A total of 30 genotypes, including two common wheat varieties, were included in the evaluation of genetic diversity on quality and DNA levels. According to the quality attributes, spelt flours exhibited medium rheological parameters and many of them had average gluten quality. AFLP analysis was conducted to evaluate phylogenetic relationships and the genetic diversity present in the accessions. A high level of genetic diversity was revealed by the very high PIC values. Two main clusters could be separated on the dendrogram: a cluster with genotypes that have common wheat in their pedigree and another cluster consisting of pure spelt accessions. The extent of genetic diversity in the spelt germplasm collections was confirmed not only by molecular markers but on the basis of quality assessment.

Restricted access

327 372 Deyab, M. A., Nemat Allah, M. M. and El-Adl, M. F. (2002): Phytoplankton diversity in some ponds at new Damietta-Egypt. - Egyp. J. Phyco. 3 : 1

Restricted access

The genetic diversity of 116 spring bread wheat cultivars released in Kazakhstan from 1929-2004 was studied by means of a genealogical analysis. The tendency of genetic diversity to change over time was traced by analysing a series of n ´ m matrices, where n is the number of released cultivars and m is the number of landrace ancestors. The pool of landrace ancestors of spring wheat cultivars in 1929-2004 contained a total of 114 landraces and old varieties, including 19 from Kazakhstan and Central Asia and 23 from neighbouring regions of Russia. The original ancestors differ significantly in frequency of presence and hence in their importance in the genepool of spring wheats cultivated in Kazakhstan. Significant differences in the contributions of dominant ancestors to cultivars for various regions have been revealed, showing that those ancestors were specifically adapted to different growing conditions. During the past 75 years, genetic diversity has increased due to the wide use of foreign materials in breeding programmes. A more detailed study has shown that during the period analysed, 15 landraces from Kazakhstan and neighbouring regions of Central Asia and Russia (35% of local germplasm) were lost from the pedigrees. The cluster structure of modern cultivars included in the Kazakhstan Official List (2002) was established. By analysing coefficients of parentage, significant differences in the genetic diversity of cultivars from various growing regions were revealed.

Restricted access

Abstract

A key structural component in peat bog formation is Sphagnum spp., which determines very specific associated environmental conditions. The aim of this study was to characterise some of the key factors affecting the diversity, species richness and abundance of sphagnum inhabiting ground beetles and to examine the maintenance of stable populations of cold adapted specialised peat bog species. A total of 52 carabid species were recorded by pitfall traps along six main habitats, such as the lagg zone, pine bog, hollows, hummock open bog and dome. The results are characterised by a low diversity, which vary significantly among habitat types, and include a high abundance of a few carabid species. Among the variables influencing carabid species richness and abundance were plant cover, pH and the conductivity of the Sphagnum mat water. Vascular plant cover was a key factor shaping carabid beetle assemblages in the slope and the dome, while electric conductivity affected carabid beetle assemblage in the lagg. Whereas, the water level was the most important factor for the hollows. At the same time, peat bog specialists showed low sensitivity to the gradient of the analysed variables. Most of the specialised species are protected boreal beetles in the temperate zone of Europe, and therefore Belarusian peat bogs are a significant repository of cold adapted specialised bog species and potentially represent a significant refugia for these species in the context of global warming.

Restricted access

Berger, W.H. and F.L. Parker. 1970. Diversity of planctonic Foraminifera in deep sea sediments. Science 168:1345-1347. Diversity of planctonic Foraminifera in deep sea sediments Science

Restricted access

Alatalo, R. and R. Alatalo. 1977. Components of diversity: Multivariate analysis with interaction. Ecology 58: 900-906. Components of diversity: Multivariate analysis with interaction

Restricted access