Analysis of the clinal variation pattern inSilene latifolia (Caryophyllaceae) pollen morphology

1987 ◽  
Vol 156 (1-2) ◽  
pp. 5-11 ◽  
Author(s):  
Honor C. Prentice
Keyword(s):  
Pollen Morphology ◽  
Clinal Variation ◽  
Variation Pattern

Leaf morphology of Claytonia virginica: racial and clinal variation

1984 ◽  
Vol 62 (7) ◽  
pp. 1469-1473 ◽  
Author(s):  
Jeff J. Doyle
Keyword(s):  
Seasonal Cycle ◽  
Environmental Gradients ◽  
Leaf Length ◽  
Width Ratio ◽  
Total Solar Radiation ◽  
Clinal Variation ◽  
Variation Pattern ◽  
Spring Ephemeral ◽  
Claytonia Virginica ◽  
Pattern Of Variation

Differences in average leaf length to width ratio are found to characterize the four chemical and cytological races of the geophytic spring ephemeral Claytonia virginica L. (Portulacaceae). Two races with wide leaves are mostly northern in distribution, while two other races having narrower leaves are predominantly southern. Within each race, a statistically significant north–south cline in leaf ratio is observed, mirroring the variation pattern observed for the species as a whole. Several ecological variables, including zenith angle of the sun and total solar radiation, also show north–south gradients when measured over the aboveground portion of the Claytonia virginica seasonal cycle and corrected for the time of flowering of the species at different latitudes. It is suggested that the clinal pattern of variation observed in the species has evolved in response to these environmental gradients.

Range-wide genetic variation of black spruce

1978 ◽  
Vol 8 (4) ◽  
pp. 463-473 ◽  
Author(s):  
E. K. Morgenstern
Keyword(s):  
Black Spruce ◽  
Atlantic Coast ◽  
Principal Component ◽  
Clinal Variation ◽  
Variation Pattern ◽  
Breeding Programs ◽  
Total Height ◽  
Seed Sources ◽  
Natural Stands ◽  
Major Factors

Initiation and cessation of growth and total height of seedlings at ages 2 and 3 years were measured in a nursery experiment with 100 seed sources of Piceamariana (Mill.) B.S.P. from natural stands sampled across the range from the Atlantic Coast to Alaska. Correlations with climatic and geographic factors were calculated and principal component, variance, and regression analyses made. The results showed that photoperiod and temperature were major factors of natural selection and that a clinal variation pattern is predominant. Since south–north trends of photoperiod and temperature are closely related to latitude, the regression of phenological variables and of height on latitude of origin gave an indication of response gradients. Total height changed by 2 to 11% from the experimental mean if a seed source was moved 1° of latitude north or south from its native area to a new site. The consequences for seed movement and breeding programs are discussed.

Evolution of Angiosperm Pollen: 8. Lamiids

2020 ◽  
Vol 105 (3) ◽  
pp. 323-376
Author(s):  
Li-E Yang ◽  
Lu Lu ◽  
Kevin S. Burgess ◽  
Hong Wang ◽  
De-Zhu Li
Keyword(s):  
Maximum Likelihood ◽  
Pollen Morphology ◽  
Pollen Size ◽  
State Transitions ◽  
Character State ◽  
Evolutionary Mechanisms ◽  
Pollen Characters ◽  
Exine Ornamentation ◽  
Shape Class ◽  
Pollen Character

Lamiids, a clade composed of approximately 15% of all flowering plants, contains more than 50,000 species dispersed across 49 families and eight orders (APG IV, 2016). This paper is the eighth in a series that analyzes pollen characters across angiosperms. We reconstructed a maximum likelihood tree based on the most recent phylogenetic studies for the Lamiids, comprising 150 terminal genera (including six outgroups) and covering all eight orders and 49 families within the clade. To illustrate pollen diversity across the Lamiids, pollen grains from 22 species (22 genera in 14 families) were imaged under light, scanning, and transmission electron microscopy. Eighteen pollen characters that were documented from previous publications, websites, and our new observations were coded and optimized onto the reconstructed phylogenetic tree using Fitch parsimony, maximum likelihood, and hierarchical Bayesian analysis. Pollen morphology of the Lamiids is highly diverse, particularly in shape class, pollen size, aperture number, endoaperture shape, supratectal element shape, and tectum sculpture. In addition, some genera show relatively high infrageneric pollen variation within the Lamiids: i.e., Coffea L., Jacquemontia Choisy, Justicia L., Pedicularis L., Psychotria L. nom. cons., Sesamum L., Stachytarpheta Vahl, and Veronica L. The plesiomorphic states for 16 pollen characters were inferred unambiguously, and 10 of them displayed consistent plesiomorphic states under all optimization methods. Seventy-one lineages at or above the family level are characterized by pollen character state transitions. We identified diagnostic character states for monophyletic clades and explored palynological evidence to shed light on unresolved relationships. For example, palynological evidence supports the monophyly of Garryales and Metteniusaceae, and sister relationships between Icacinaceae and Oncothecaceae, as well as between Vahliales and Solanales. The evolutionary patterns of pollen morphology found in this study reconfirm several previously postulated evolutionary trends, which include an increase in aperture number, a transition from equatorially arranged apertures to globally distributed ones, and an increase in exine ornamentation complexity. Furthermore, there is a significant correlation between pollen characters and a number of ecological factors, e.g., pollen size and pollination type, pollen ornamentation and pollination type, and shape class and plant growth form. Our results provide insight into the ecological, environmental, and evolutionary mechanisms driving pollen character state changes in the Lamiids.

New Findings on Scrophularia sect. Mimulopsis (Scrophulariaceae) from Iran

2019 ◽  
Vol 27 (4) ◽  
pp. 238-247
Author(s):  
Massoud Ranjbar ◽  
Narges Rahchamani
Keyword(s):  
New Species ◽  
Pollen Morphology ◽  
Conservation Status ◽  
Morphological Characters ◽  
Northern Iran ◽  
Distribution Maps ◽  
New Findings ◽  
Tehran Province ◽  
Micromorphological Characters ◽  
A New Species

Scrophularia dianatnejadii Ranjbar & Rahchamani, a new species from Tehran Province in northern Iran, is described and illustrated. It is closely related to S. amplexicaulis Benth. and shares with it some diagnostic morphological characters such as habit, plant indument, phyllotaxy, and corolla shape and color. Both species are placed in Scrophularia L. sect. Mimulopsis Boiss. Macro- and micromorphological characters of the two are examined and compared. Pollen morphology of these species is investigated using SEM. Detailed descriptions, illustrations, distribution maps, and conservation status of both species are provided.

Pollen morphology of selected tundra plants from the high Arctic of Ny-Ålesund, Svalbard

2013 ◽  
Vol 23 (2) ◽  
pp. 103-115 ◽  
Author(s):  
Yifeng YAO ◽  
Qi ZHAO ◽  
Subir BERA ◽  
Xiaoli LI ◽  
Chengsen LI
Keyword(s):  
Pollen Morphology ◽  
High Arctic

Pollen characterization of ornamental species of Mammillaria Haw. (Cactaceae/Cactoideae)

2019 ◽  
Vol 6 (1) ◽  
pp. 13 ◽  
Author(s):  
Denise M. D. S. Mouga ◽  
Gabriel R. Schroeder ◽  
Nilton P. Vieira Junior ◽  
Enderlei Dec
Keyword(s):  
Pollen Morphology ◽  
Pollen Grains ◽  
Radial Symmetry ◽  
Morphological Data ◽  
Medium Size ◽  
Ornamental Species

The pollen morphology of thirteen species of Cactaceae was studied: M. backebergiana F.G. Buchenau, M. decipiens Scheidw, M. elongata DC, M. gracilis Pfeiff., M. hahniana Werderm., M. marksiana Krainz, M. matudae Bravo, M. nejapensis R.T. Craig & E.Y. Dawson, M. nivosa Link ex Pfeiff., M. plumosa F.A.C. Weber, M. prolifera (Mill.) Haw, M. spinosissima var. “A Peak” Lem. and M. voburnensis Scheer. All analysed pollen grains are monads, with radial symmetry, medium size (M. gracilis, M. marksiana, M. prolifera, large), tricolpates (dimorphs in M. plumosa [3-6 colpus] and M. prolifera [3-6 colpus]), with circular-subcircular amb (quadrangular in M. prolifera and M. plumosa with six colpus). The pollen grains presented differences in relation to the shape and exine thickness. The exine was microechinate and microperforated. The pollen morphological data are unpublished and will aid in studies that use pollen samples. These pollen grains indicate ornamental cacti.

Segregation and speciation in the Neogene planktonic foraminiferal clade Globoconella

Paleobiology ◽  
1999 ◽  
Vol 25 (3) ◽  
pp. 383-395 ◽  
Author(s):  
Cynthia E. Schneider ◽  
James P. Kennett
Keyword(s):  
Morphological Evolution ◽  
Evolutionary Divergence ◽  
Clinal Variation ◽  
Near Surface ◽  
Surface Warming ◽  
Isotopic Analyses ◽  
Oxygen Isotopic ◽  
Morphological Differences ◽  
Middle Pliocene ◽  
Water Depths

The origin of the Neogene planktonic foraminifer Globorotalia (Globoconella) pliozea in the subtropical southwest Pacific has been attributed to its isolation resulting from intensification of the Subtropical Divergence (Tasman Front). Oxygen isotopic analyses suggest that, although the Subtropical Divergence may have played a role, the evolution of Gr. (G.) pliozea was facilitated by depth segregation of Gr. (G.) conomiozea morphotypes (low and high conical) during an interval of near-surface warming and increasing thermal gradient. Oxygen isotopic analyses suggest that low conical morphotypes of Gr. (G.) conomiozea inhabited greater depths than high conical morphotypes. Low conical forms of Gr. (G.) conomiozea are considered ancestral to the low conical species, Gr. (G.) pliozea. Oxygen isotopes indicate that Gr. (G.) pliozea inhabited greater depths than its ancestor, Gr. (G.) conomiozea.These data are consistent with depth-parapatric and depth-allopatric models, but not with a sympatric model of speciation. In the allopatric model, reproduction at different water depths acts as a barrier between morphotypes. In the parapatric model, clinal variation along a depth gradient acts as a barrier between morphotypes living at the limits of the gradient. Depth segregation in both models results in genetic isolation and evolutionary divergence. Our data support a correlation between morphological evolution and habitat changes in the Globoconella clade, implying separation of populations as a driving force for morphological evolution.Ecological segregation of morphotypes and species may be related to morphology (height of the conical angle), based on the data from Gr. (G.) conomiozea and Gr. (G.) pliozea. However, morphological differences alone do not necessarily produce depth differences. Large morphological differences between Gr. (G.) pliozea and closely related Gr. (G.) puncticulata did not result in isotopic and therefore depth differences between these species. These species coexisted at the same water depths for nearly 1 m.y. Thus, it is unlikely that the extinction of Gr. (G.) pliozea in the middle Pliocene resulted from competition with Gr. (G.) puncticulata, as previously suggested.

Pollen morphology of Persicaria section Cephalophilon (Polygonaceae)

2021 ◽  
Vol 307 (2) ◽  
Author(s):  
Min-Jung Kong ◽  
Jun-Ho Song ◽  
Suk-Pyo Hong
Keyword(s):  
Pollen Morphology
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