A Multivariate Analysis of the Morphological Variability in the Foraminiferal Species Florilus boueanus (d'Orbigny, 1846) from the "Neogene" of Northern Belgium

1975 ◽  
Vol 21 (4) ◽  
pp. 460 ◽  
Author(s):  
F. J. C. de Meuter ◽  
F. E. Symons
2017 ◽  
Vol 222 ◽  
pp. 180-186 ◽  
Author(s):  
Elham Norouzi ◽  
Javad Erfani-Moghadam ◽  
Arash Fazeli ◽  
Ali Khadivi

2021 ◽  
Vol 52 (1) ◽  
pp. 249-258
Author(s):  
Abdulrahman & et al.

Myrtaceae family is widely distributed in Asia has been the largest group of plant; mainly trees and few shrubs. Distributed all over the world in tropical and subtropical areas. Syzygium is the largest genus with economical value found all over the Malaysian Peninsular. Evolutionary relationships within the Syzygium is unclear and there are currently no reliable criteria to divide the genus into manageable entities for systematic study. Species of Syzygium is the richest genus of woody plants in South East Asia with approximately 1000 or more species but little is known about the genus. Syzygium polyanthum Wight is one of the favourites Ulam that have been consumed for ages in Peninsular Malaysia and also as herbal medicine. The species is widely misunderstood due to extreme morphological variability, similarity in aroma and flavor. The species is substituted or adulterated with several other species. The study was aimed to construct phenetic tree and unsupervised multivariate analysis from morphological and anatomical the data matrix.  Phenetic analysis, Principal component and hierarchical cluster analysis revealed they are two different cultivars species  but inter variation exited among cultivars of same species.  The above documented information has added new  taxonomic information with regard to the identification of the cultivars in Peninsular Malaysia. The study recommends further study on de novo sequence of Serai kayu and Serai kayu hutan.


Botany ◽  
2008 ◽  
Vol 86 (5) ◽  
pp. 520-532 ◽  
Author(s):  
Safia Belhadj ◽  
Arezki Derridj ◽  
Yves Auda ◽  
Charles Gers ◽  
Thierry Gauquelin

To study the morphological variability within and among Pistacia atlantica Desf. populations, a comparative analysis was undertaken in eight wild populations grown under different climatic conditions in Algeria. This study addresses the morpho-biometrical aspect of the leaves and the fruits, as well as the micromorphological aspect of leaves. ANOVA as well as mean comparison of the morphological traits revealed a significant diversity within and among the populations. Furthermore, in the multivariate analysis, the populations were separated into four different groups through the discriminating variables: leaf and leaflet dimensions, number of pairs of leaflets, leaf wings, leaf smell and colour, terminal leaflet size and apex, and finally fruit colour and shape. These results showed the originality of the Algerian populations as compared with those commonly described for this species in the literature, in particular by the occurrence of wax on the leaves. The morphological variability exhibited by the Algerian populations of P. atlantica may be interpreted as relevant to the ecological plasticity and the physiological mechanisms discussed in this article.


2020 ◽  
Vol 261 ◽  
pp. 108968
Author(s):  
Edith Salazar-Villa ◽  
Lilia Alcaraz-Meléndez ◽  
Josefina León-Félix ◽  
José Basilio Heredia ◽  
Federico Soto-Landeros ◽  
...  

2018 ◽  
Vol 120 ◽  
pp. 162-170 ◽  
Author(s):  
Hossein Fereidoonfar ◽  
Hossein Salehi-Arjmand ◽  
Ali Khadivi ◽  
Morteza Akramian

Nematology ◽  
2014 ◽  
Vol 16 (2) ◽  
pp. 149-162 ◽  
Author(s):  
Danny A. Humphreys-Pereira ◽  
Axel A. Elling

The morphology of Meloidogyne chitwoodi is relatively poorly characterised. In a recent study, morphological variation in adult females of M. chitwoodi was analysed. However, comparable data are lacking for adult males and second-stage juveniles (J2). Therefore, our studies of four M. chitwoodi isolates from the western USA, representing all currently known races and pathotypes, were designed to characterise intraspecific morphological variability in J2 and males and to compare it to variability found in adult females. Multivariate analysis of variance indicated statistically significant variation among isolates for both J2 and males. Moreover, for adult males, canonical discriminant analysis grouped races with their respective pathotypes. In addition, we analysed two morphological features that were previously uncharacterised for M. chitwoodi, i.e., stylet knob width and distance from secretory-excretory pore to anterior end. Both of these characters may be useful in distinguishing M. chitwoodi from closely related species. SEM clearly showed the presence of areolations along the bodies of J2, thereby separating M. chitwoodi from M. fallax and M. minor. In summary, this study indicates that M. chitwoodi J2 and adult males show substantially more intraspecific morphological variability than previously known. Consequences for diagnostics are discussed.


1966 ◽  
Vol 24 ◽  
pp. 188-189
Author(s):  
T. J. Deeming

If we make a set of measurements, such as narrow-band or multicolour photo-electric measurements, which are designed to improve a scheme of classification, and in particular if they are designed to extend the number of dimensions of classification, i.e. the number of classification parameters, then some important problems of analytical procedure arise. First, it is important not to reproduce the errors of the classification scheme which we are trying to improve. Second, when trying to extend the number of dimensions of classification we have little or nothing with which to test the validity of the new parameters.Problems similar to these have occurred in other areas of scientific research (notably psychology and education) and the branch of Statistics called Multivariate Analysis has been developed to deal with them. The techniques of this subject are largely unknown to astronomers, but, if carefully applied, they should at the very least ensure that the astronomer gets the maximum amount of information out of his data and does not waste his time looking for information which is not there. More optimistically, these techniques are potentially capable of indicating the number of classification parameters necessary and giving specific formulas for computing them, as well as pinpointing those particular measurements which are most crucial for determining the classification parameters.


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