A depth cline in deep-sea octopods (Cephalopoda: Graneledone) in the northeast Pacific Ocean

2020 ◽  
Vol 96 (2) ◽  
pp. 323-340
Author(s):  
Janet R Voight ◽  
Jessica A Kurth ◽  
Richard E Strauss ◽  
Jan M Strugnell ◽  
Louise A Allcock
Keyword(s):  
Genetic Divergence ◽  
Principal Component ◽  
Gill Lamella ◽  
12S Rrna ◽  
Head Width ◽  
Skin Texture ◽  
Canonical Correlations ◽  
Northeast Pacific ◽  
Gill Lamellae ◽  
Morphological Differences

Bathyal octopods of the genus Graneledone Joubin, 1918 in the northeast Pacific differ dramatically in skin texture. To test the hypothesis that these differences are associated with geography, we quantified the skin warts and tubercles of 50 specimens collected between 36°N and 46°N from 1116 to 2850 m depth. Using Principal Component Analysis (PCA), we analyzed the numbers of mantle and head warts, mantle and web tubercles, arm suckers, and inner and outer gill lamellae, adding head width as a size proxy. We used Canonical Correlation Analysis to explicitly test the relationship of morphology to depth and latitude. Sequences of 12S rRNA, 16S rRNA, and COI genes from 12 individuals quantified genetic divergence. PCA revealed correlated variation in head width, arm suckers, and gill lamella counts opposed by skin texture on PC1; PC2 showed correlated variation in skin texture opposed by gill lamella counts. Both components correlate with depth and latitude but, as most shallow specimens came from southern localities, the correlation with latitude may be artefactual. is relationship is corroborated by the canonical correlations. Octopods from greater depths are smaller than those from shallower depths, have rougher skin texture, and fewer suckers and gill lamellae. Clades of shallow and deep octopods show 0.8% genetic divergence in COI (Kimura two-parameter distance), not inconsistent with intraspecific differentiation. We conclude that the variation is likely clinal with depth. The observed morphological differences may result from differences in food availability and oxygen saturation with depth.

Morphological Differences between Hatchery and Wild Populations of Coho Salmon (Oncorhynchus kisutch): Environmental versus Genetic Origin

1991 ◽  
Vol 48 (9) ◽  
pp. 1783-1791 ◽  
Author(s):  
D. P. Swain ◽  
B. E. Riddell ◽  
C. B. Murray
Keyword(s):  
Maternal Effects ◽  
Genetic Divergence ◽  
Coho Salmon ◽  
Oncorhynchus Kisutch ◽  
Principal Component ◽  
Wild Populations ◽  
Genetic Origin ◽  
Environmental Component ◽  
Morphological Differences ◽  
Median Fins

Previous studies have demonstrated morphological differences between hatchery-reared coho salmon (Oncorhynchus kisutch) of hatchery origin and wild-reared coho of wild origin. We tested for a genetic component to this divergence by comparing coho from hatchery and wild populations both reared in the same hatchery environment and for an environmental component by comparing hatchery- and wild-reared coho both of wild origin. As in the previous studies, wild-reared fish from wild populations had greater head dimensions, larger median fins, and deeper bodies than did hatchery-reared fish from hatchery populations. This difference, summarized by the first principal component (PC1) of the size-adjusted data, was related to rearing environment rather than to genetic differences between hatchery and wild populations. Genetic divergence (or maternal effects) did occur between hatchery and wild populations along PC2 and PC3, but this divergence was slight compared with the environmentally induced differences between the two types of fish along PC1.

Genetic Evaluation and Bi-plot Analysis in Okra Hybrids for Yield, Quality Components and YVMV Resistance

2018 ◽  
Vol 5 (04) ◽  
Author(s):  
SS SOLANKEY ◽  
ANIL K SINGH
Keyword(s):  
Genetic Divergence ◽  
Principal Component ◽  
F1 Hybrids ◽  
Genetic Advance ◽  
Economic Traits ◽  
Cross Combination ◽  
Plot Analysis ◽  
Eigen Value ◽  
Coefficient Of Variability ◽  
Yield Quality

Fifty one okra F1 hybrids (using 17 lines as female and 3 testers as male parent) were evaluated in RCBD design during two different consecutive seasons (summer and rainy). Phenotypic coefficient of variability (PCV) was higher than genotypic coefficient of variability (GCV) for all studied character exhibiting environmental effects on the expression of characters. Heritability (h2b) along with genetic advance per cent of mean was found highest for character YVMV (86.95% and 150.61%). All the 51 okra hybrids were grouped into 4 distinct clusters in which Cluster II was the largest cluster having 28 F1s (54.90% of total F1s) followed by Cluster I with 14 F1s (27.45% of total F1s). Out of the major 6 PCs, 4 principal components (PC1, PC2, PC3 and PC4) accounted with proportionate values of 22.61, 17.22, 11.87 and 10.63%, respectively and contributed 62.33 % of the cumulative variation having Eigen value more than one. Moreover, based on PCs and genetic divergence in Cluster I and Cluster IV for plant height, YVMV and number of fruit per plant is important to identify the best cross combination (Arka Abhay × Arka Anamika) in okra. Therefore, the best cross combinations for improvement in various economic traits can be recommended on the basis of genetic divergence and principal component analysis in okra.

ESTIMATION OF GENETIC DIVERGENCE IN CHILLI PEPPER (CAPSICUM ANNUUM L.) GENOTYPES FOR MORPHOLOGICAL AND FRUIT TRAITS UNDER HOT CLIMATE OF UMERKOT, SINDH

2021 ◽  
Vol 37 (1) ◽  
pp. 21-28
Author(s):  
A. Memon ◽  
R. Ahmad ◽  
M. S. Depar ◽  
A. K. Pathan ◽  
D. Ibrar
Keyword(s):  
Cluster Analysis ◽  
Genetic Divergence ◽  
Agricultural Research ◽  
Arid Zone ◽  
Principal Component ◽  
Fruit Weight ◽  
Economic Traits ◽  
Chilli Pepper ◽  
Hot Climate ◽  
Improvement Programs

Thirty-two genotypes of chilli from three different sources (local dandicuts, AVRDC and PGRI PARC) were evaluated for the presence of genetic divergence among them for different agro-economic traits i.e., plant height, stem girth, fruit length, fruit girth, number of fruits per plant, number of seed per fruit, fresh fruit weight and dry fruit weight at Arid Zone Agricultural Research Institute, Umerkot, Sindh during 2018. All these genotypes were found to be significantly different from each other for all the studied traits. For further diversity analysis, multivariate analyses like principal component analysis (PCA) and Cluster analysis were also performed to figure out the traits responsible for maximum variability and grouping of genotypes according to their similarities and differences for their future utilization in chilli breeding programs. PCA analysis showed that first four PCs exhibited 82.79% of the total variability among these 32 chilli genotypes. Cluster analysis showed four different sub-clusters and the genotypes from every single source merge in each sub-cluster, thus showing that chilli genotypes are from different geographical backgrounds. Based on these results, the chilli genotypes can be further utilized in future chilli improvement programs in Pakistan.  Genotypes AZRI-DS-14, AZRI-DS-01 and AVPP-9804 showed better performance.

scholarly journals Intraspecific ecomorphological variations in Poecilia reticulata (Actinopterygii, Cyprinodontiformes): comparing populations of distinct environments

2015 ◽  
Vol 105 (2) ◽  
pp. 217-222 ◽  
Author(s):  
Fábio T. Mise ◽  
Fagner de Souza ◽  
João P. A. Pagotto ◽  
Erivelto Goulart
Keyword(s):  
Poecilia Reticulata ◽  
Principal Component ◽  
Water Current ◽  
Way Of Life ◽  
Morphological Variations ◽  
Current Availability ◽  
Environment Type ◽  
Morphological Variables ◽  
Males And Females ◽  
Morphological Differences

ABSTRACT Morphological variations, according to the principles of ecomorphology, can be related to different aspects of the organism way of life, such as occupation of habitats and feeding behavior. The present study sought to examine the intraspecific variation in two populations of Poecilia reticulata Peters, 1859, that occur in two types of environments, a lotic (Maringá Stream) and a lentic (Jaboti Lake). Due to a marked sexual dimorphism, males and females were analyzed separately. Thus, the proposed hypotheses were that the populations that occur in distinct environments present morphological differences. The morphological variables were obtained using morphometric measurements and the ecomorphological indexes. The data were summarized in a Principal Component Analysis (PCA). A Multivariate Analysis of Variance (Manova) was made to verify significant differences in morphology between the populations. Males and females showed similar ecomorphological patterns according to the environment they occur. In general the population from Maringá Stream had fins with major areas, and the Jaboti Lake population eyes located more dorsally. Additionally, others morphological differences such as wider mouth of the males from Maringá Stream, wider heads on Jaboti Lake females and more protractible mouths on males from Jaboti Lake suggest a set of environmental variables that can possibly influence the ecomorphological patterns of the populations, as the water current, availability of food resources and predation. In summary, the initial hypotheses could be confirmed, evidencing the occurrence of distinct ecomorphotypes in the same species according to the environment type.

scholarly journals Genetic diversity and phylogenetic behavior of some minor legumes

2016 ◽  
Vol 7 (1) ◽  
Author(s):  
James Oludare Agbolade ◽  
Ronke Justina Komolafe
Keyword(s):  
Genetic Diversity ◽  
Principal Component ◽  
Calyx Lobe ◽  
Descriptive Statistics ◽  
International Institute ◽  
Mean Values ◽  
Phylogenetic Relatedness ◽  
Petal Length ◽  
Morphological Differences ◽  
Range Test

Twenty-four accessions of twelve species minor legumes collected from the germplasm unit of the International Institute of Tropical Agriculture Ibadan, Nigeria were evaluated for their genetic diversities and phylogenetic relatedness. The accessions were planted into plots of 5 ridges of 5 meters long, spaced 1 meter apart and replicated three times at the Federal University Oye-Ekiti Teaching and Research Farm. The diversity and the relative phylogeny of the accessions were assessed through their floral morphological differences and the mean values between two accessions were evaluated by descriptive statistics. Principal component analysis was employed to identify the most discriminatory floral morphological traits and the similarities among the 24 accessions were assessed by cluster analysis (CA). Descriptive statistics through Duncan multiple range test adopted revealed genetic diversity and phylogenetic relatedness among the accessions. The first two principal component axes explained 64.66% of the total floral morphological variation. Standard petal length, calyx lobe length and stipule length contributed most of the variations in the legume accession. CA grouped the 24 accessions into six clusters. The study revealed intra-specific similarities and inter-specific floral morphological differences among the studied accessions.

scholarly journals Unusually low genetic divergence at COI barcode locus between two species of intertidalThalassaphorura(Collembola: Onychiuridae)

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5021 ◽  
Author(s):  
Xin Sun ◽  
Anne Bedos ◽  
Louis Deharveng
Keyword(s):  
Genetic Divergence ◽  
Dna Barcode ◽  
Intertidal Habitat ◽  
Species Classification ◽  
Arthropod Species ◽  
Fresh Material ◽  
Interspecific Divergence ◽  
Collembolan Species ◽  
Morphological Differences ◽  
Intertidal Ecosystems

Species classification is challenging when taxa display limited morphological differences. In this paper, we combined morphology and DNA barcode data to investigate the complicated taxonomy of two Onychiurid Collembolan species.Thalassaphorura thalassophilaandThalassaphorura debilisare among the most common arthropod species in intertidal ecosystems and are often considered to be synonymous. Based on morphological and barcode analyses of fresh material collected in their type localities, we redescribed and compared the two species. However, their morphological distinctiveness was supported by a molecular divergence much smaller than previously reported at the interspecific level among Collembola. This divergence was even smaller than inter-population divergences recognized in the related edaphic speciesT. zschokkei, as well as those known between MOTUs within many Collembolan species. Our results may indicate a link between low genetic interspecific divergence and intertidal habitat, as the only biological peculiarity of the two species of interest compared to other Collembolan species analyzed to date is their strict intertidal life.

Can morphological characters be used to identify the pond-reared offspring of wild Chinese mitten crabs, Eriocheir sinensis, from different basins?

Crustaceana ◽  
2019 ◽  
Vol 92 (8) ◽  
pp. 957-978
Author(s):  
Xiaodong Jiang ◽  
Xugan Wu ◽  
Haining Wang ◽  
Yuhong Yang ◽  
Yongxu Cheng
Keyword(s):  
Morphological Difference ◽  
Principal Component ◽  
Morphological Characters ◽  
Eriocheir Sinensis ◽  
Stepwise Discriminant Analysis ◽  
Chinese Mitten Crab ◽  
Artificial Culture ◽  
Mitten Crab ◽  
Mitten Crabs ◽  
Morphological Differences

Abstract Although morphology is always used to distinguish wild Chinese mitten crab (Eriocheir sinensis) populations, whether morphology could be used to identify the pond-reared offspring of wild E. sinensis populations has remained unclear. This study was undertaken to examine the morphological difference of wild E. sinensis (G0) from the Yangtze River (YR), Huang River (HR) and Liao River (LR) as well as their pond-reared offspring (G1). The results showed that: (1) The amount of significantly different parameters of three G1 populations was evidently less than that of three G0 populations; (2) G0 and G1 individuals of each population were clearly separated by principal component analysis, furthermore, three G0 populations were clearly separated while three G1 populations were not well distinguished from each other; (3) discrimination accuracy of G1 individuals in stepwise discriminant analysis was obviously lower than that of G1 populations; (4) G0 and G1 populations were clustered into two separate clusters in the cluster analysis. In conclusion, morphological differences between wild E. sinensis populations had disappeared after one generation of artificial culture, and morphology thus probably cannot be used to distinguish the pond-reared offspring originated from three wild E. sinensis populations.

scholarly journals Mexican dancer in Ecuador: molecular confirmation, embryology and planktotrophy in the sea slug Elysia diomedea

2020 ◽  
Vol 52 ◽  
Author(s):  
Lola Moreano-Arrobo ◽  
Oscar D. Pérez ◽  
Federico D. Brown ◽  
Fernanda X. Oyarzún ◽  
Cristian B. Canales-Aguirre
Keyword(s):  
Genetic Information ◽  
Ex Situ ◽  
Adult Size ◽  
Mtdna Sequences ◽  
Cell Stage ◽  
Egg Capsules ◽  
Northeast Pacific ◽  
Morphological Differences ◽  
General Aspects ◽  
Veliger Larvae

Elysia diomedea varies in adult size and color across its geographical distribution in Ecuador. Because of morphological variation and the absence of genetic information for this species in Ecuador, we analyzed mtDNA sequences in three populations (Ballenita, La Cabuya, and Mompiche) and confirmed that (1) individuals from the three locations belonged to E. diomedea and (2) that there was no population structure that could explain their morphological differences. Next, we analyzed general aspects about the reproductive biology and embryology of this species. Live slugs from the Ballenita population were maintained and reproduced ex situ. Egg ribbons and embryos were fixed and observed by brightfield and confocal microscopy. We observed a single embryo per capsule, 98 embryos per mm2 of egg ribbon, and compared the cleavage pattern of this species to other heterobranchs and spiralians. E. diomedea early development was characterized by a slight unequal first cleavage, occurrence of a 3-cell stage in the second cleavage, and the formation of an enlarged second quartet of micromeres. We observed clear yolk bodies in the egg capsules of some eggs ribbons at early stages of development. Both reproductive and embryological characteristics, such as presence of stomodeum in the larva, and ingestion of particles after hatching confirmed the planktotrophic veliger larvae of this species, consistent with the majority of sacoglossans from the Eastern and Northeast Pacific Oceans.

scholarly journals GENETIC DIVERGENCE ANALYSIS IN HRDC RICE (Oryza sativa L.) HYBRIDS IN BANGLADESH

2016 ◽  
Vol 27 (2) ◽  
pp. 25-32
Author(s):  
A. Ahmed ◽  
S. G. Shaon ◽  
M. S. Islam ◽  
P. S. Saha ◽  
M. M. Islam
Keyword(s):  
Genetic Divergence ◽  
Oryza Sativa L ◽  
Principal Component ◽  
Dry Season ◽  
Spikelet Fertility ◽  
Mean Values ◽  
Panicle Number ◽  
Cluster Distance ◽  
The Mean ◽  
Yield Maximization

Genetic divergence of 48 IRRI developed F1 rice hybrids were studied through Mahalanobis D2 and principal component analysis for ten characters in Gazipur and Pabna district during dry season 2012-13. Among 48 genotypes, cluster analysis resulted in five clusters following Ward’s method. During dry season for both regions, cluster I incorporated the highest number of genotypes. Significant differences among the genotypes but non-significant differences among replications were noticed for most of the parameters under study. The inter-cluster distance was larger than intra-cluster distance suggesting wider diversity among the genotypes. In Gazipur, the maximum inter-cluster D2 value was recorded between cluster III and V (6.69) and the minimum between cluster II and IV (0.69). The intra-cluster distance was maximum in cluster IV (3.60) and minimum in cluster I (0.33). In Pabna, maximum inter-cluster distance was exhibited between cluster IV and II (16.43) but minimum between cluster II and III (3.98). Maximum intra-cluster distance (4.40) was recorded in cluster IV whereas minimum in cluster I (0.83). Based on positive value of vector 1 and vector 2, panicle number m-2, spikelet fertility (%) and 1000-grain wt. (g) had maximum contribution towards genetic divergence among the characters studied. Cluster means indicated considerable differences in the mean values of different parameters. The highest cluster means for panicle weight (g), spikelet fertility (%), 1000 grain wt. (g) and grain yield (kg ha-1) were derived from cluster IV. Therefore, more prominence should be given to the lines under cluster IV that having genetic potentiality to contribute better for yield maximization of hybrid rice.

Morphological and molecular systematic investigation of Laurencia karachiana sp. nov. (Ceramiales, Rhodophyta) from Karachi, Pakistan

Phytotaxa ◽  
2019 ◽  
Vol 404 (1) ◽  
pp. 23 ◽  
Author(s):  
RABIA BIBI ◽  
VALÉRIA CASSANO ◽  
ROSÂNGELA DA SILVA MEDEIROS ◽  
SHAHNAZ RASHID ◽  
MUNAWWER RASHEED
Keyword(s):  
Sri Lanka ◽  
Genetic Divergence ◽  
Novel Species ◽  
Systematic Investigation ◽  
Sensu Stricto ◽  
Molecular Systematic ◽  
Interspecific Divergence ◽  
Morphological Differences ◽  
Open Question ◽  
Rbcl Phylogeny

Laurencia karachiana sp. nov. is described from the Karachi coast of Pakistan, based on rbcL and COI-5P genes sequences. The molecular analyses for both markers positioned L. karachiana within Laurencia sensu stricto and it possesses all vegetative and reproductive structures typical of the genus. Laurencia karachiana grouped with Laurencia sp. from Sri Lanka for both markers. The genetic divergence between these taxa for rbcL was only 0.27%, whereas for COI-5P was much higher, 2.7%. The latter is within ranges of interspecific divergence for Laurencia s.s. The discrepancy of divergence between these markers and the lack of description and illustrations of Laurencia sp. from Sri Lanka for comparison leave the identity of Laurencia sp. as an open question. The rbcL phylogeny resolved L. karachiana and Laurencia sp. as sister to a subclade formed by sequences of Laurencia pumila and L. pumila var. dehoopiensis from South Africa, diverging by 1.7–1.8%. This genetic divergence and also morphological differences observed support the recognition of L. karachiana as a novel species. Our finding shows that this complex from Pakistan requires major revision, because its diversity is likely underestimated.

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