scholarly journals An investigation of pollen grain thermal diversity on species level

2018 ◽  
Vol 27 (2) ◽  
pp. 170-176
Author(s):  
MUJTABA Muhammad; KAYA
Keyword(s):  
Pollen Grain ◽  
Species Level ◽  
Thermal Diversity

Pollen Morphology in the Subtribe Metrosiderinae of the Leptospermoideae (Myrtaceae) and Its Taxonomic Significance.

1981 ◽  
Vol 29 (2) ◽  
pp. 159 ◽  
Author(s):  
PA Gadek ◽  
HA Martin
Keyword(s):  
Pollen Morphology ◽  
Intraspecific Variability ◽  
Interspecific Variation ◽  
Pollen Grain ◽  
Species Level ◽  
Taxonomic Significance ◽  
Pollen Type ◽  
Interspecific Variability ◽  
Pollen Characters ◽  
Definition Of

The pollen morphology of 28 species from the subtribe Metrosiderinae (s.Bentham) is described and compared in the light of several recent taxonomic revisions of this subtribe. All species have the same basic Myrtaceous pollen type, but there is intra and interspecific variability seen in a number of the pollen characters. Intraspecific variability is related either to changes in volume and size of the pollen grain or to the occurrence of polar islands. It is concluded that the character of syncolpy or parasyncolpy as relating to the presence or absence of polar islands may not be taxonomically reliable at the species level. Interspecific variation. and thus those characters most useful in assessing the taxonomy, relate to the structure of the angle of the amb, the exine structure and sculpture and the definition, form and type of colpi and apocolpia. One species shows a difference in polarity from the rest. Three basic exine sculpture types were defined, but it was necessary to examine them under the scanning electron microscope (SEM) because their patterns could not be resolved under the light microscope. Acetolysis enhanced the definition of the smaller basic sculptures under the SEM. Generally, the pollen morphology of these species was found to support the recent taxonomic revisions of this subtribe.

ERRORS ASSOCIATED WITH HERBAGE DISSECTION ANALYSES 2. Problems of species identification

1976 ◽  
pp. 213-225
Author(s):  
I.M. Ritchie ◽  
C.C. Boswell ◽  
A.M. Badland
Keyword(s):  
New Zealand ◽  
Dry Weight ◽  
Analytical Tool ◽  
Species Level ◽  
Weight Basis ◽  
Plant Identification ◽  
Leaf Fragment ◽  
Research Division ◽  
Or Groups ◽  
Botanical Analysis

HERBACE DISSECTION is the process in which samples of herbage cut from trials are separated by hand into component species. Heavy reliance is placed on herbage dissection as an analytical tool ,in New Zealand, and in the four botanical analysis laboratories in the Research Division of the Ministry of Agriculture and Fisheries about 20 000 samples are analysed each year. In the laboratory a representative subsample is taken by a rigorous quartering procedure until approximately 400 pieces of herbage remain. Each leaf fragment is then identified to species level or groups of these as appropriate. The fractions are then dried and the composition calculated on a percentage dry weight basis. The accuracy of the analyses of these laboratories has been monitored by a system of interchanging herbage dissection samples between them. From this, the need to separate subsampling errors from problems of plant identification was, appreciated and some of this work is described here.

scholarly journals An analysis of the population of Cryptococcus neoformans strains isolated from animals in Poland, in the years 2015–2019

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Magdalena Florek ◽  
Urszula Nawrot ◽  
Agnieszka Korzeniowska-Kowal ◽  
Katarzyna Włodarczyk ◽  
Anna Wzorek ◽  
...  
Keyword(s):  
Cryptococcus Neoformans ◽  
Species Level ◽  
Molecular Type ◽  
Animal Group ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Severe Infections ◽  
Resistant Strains ◽  
World Distribution ◽  
Tof Ms

AbstractFungi belonging to the Cryptococcus neoformans/C. gattii species complex (CNGSC) are pathogens causing severe infections in humans and animals, that for humans may result in a mortality rate ranging up to 70%. The CNGSC is divided into eight major molecular types, that may differ in their virulence and susceptibility. In order to fully understand the epidemiology of cryptococcosis, it is important to study the world distribution and population structure of these pathogens. The present study is the first presenting a population of strains isolated in Poland and one of the few using a multi-species animal group as a source of the specimen. The pathogen was present in 2.375% of the tested animals. The URA5-RFLP and MALDI-TOF MS analyses have revealed that the population consisted exclusively of C. neoformans strains, with a predominance of major molecular type VNIV (C. neoformans var. neoformans). The MALDI-TOF MS was used to perform the CNGSC strains identification on both the species and sub-species level. Despite the fact that the animals providing the specimens were not treated with 5-fluorocytosine, around 10% of the tested population presented MIC values exceeding 64 mg/L, indicating the existence of the 5-fluorocytosine-resistant strains in the environment.

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