scholarly journals Macroclimatic conditions as main drivers for symbiotic association patterns in lecideoid lichens along the Transantarctic Mountains, Ross Sea region, Antarctica

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Monika Wagner ◽  
Georg Brunauer ◽  
Arne C. Bathke ◽  
S. Craig Cary ◽  
Roman Fuchs ◽  
...  
Keyword(s):  
Environmental Conditions ◽  
Latitudinal Gradient ◽  
Ross Sea ◽  
Alpha Diversity ◽  
Symbiotic Association ◽  
Dry Valleys ◽  
Climate Conditions ◽  
Continental Antarctica ◽  
Main Driver ◽  
Almost All

AbstractLecideoid lichens as dominant vegetation-forming organisms in the climatically harsh areas of the southern part of continental Antarctica show clear preferences in relation to environmental conditions (i.e. macroclimate). 306 lichen samples were included in the study, collected along the Ross Sea coast (78°S–85.5°S) at six climatically different sites. The species compositions as well as the associations of their two dominant symbiotic partners (myco- and photobiont) were set in context with environmental conditions along the latitudinal gradient. Diversity values were nonlinear with respect to latitude, with the highest alpha diversity in the milder areas of the McMurdo Dry Valleys (78°S) and the most southern areas (Durham Point, 85.5°S; Garden Spur, 84.5°S), and lowest in the especially arid and cold Darwin Area (~ 79.8°S). Furthermore, the specificity of mycobiont species towards their photobionts decreased under more severe climate conditions. The generalist lichen species Lecanora fuscobrunnea and Lecidea cancriformis were present in almost all habitats, but were dominant in climatically extreme areas. Carbonea vorticosa, Lecidella greenii and Rhizoplaca macleanii were confined to milder areas. In summary, the macroclimate is considered to be the main driver of species distribution, making certain species useful as bioindicators of climate conditions and, consequently, for assessing the consequences of climate change.

scholarly journals How do symbiotic associations in lecideoid lichens respond to different environmental conditions along the Transantarctic Mountains, Ross Sea region, Antarctica?

2021 ◽  
Author(s):  
Monika Wagner ◽  
Georg Brunauer ◽  
Arne C. Bathke ◽  
S. Craig Cary ◽  
Roman Fuchs ◽  
...  
Keyword(s):  
Environmental Conditions ◽  
Latitudinal Gradient ◽  
Ross Sea ◽  
Alpha Diversity ◽  
Dry Valleys ◽  
Climate Conditions ◽  
Symbiotic Associations ◽  
Continental Antarctica ◽  
Main Driver ◽  
Almost All

Lecideoid lichens as dominant vegetation-forming organisms in the climatically harsh areas of the southern part of continental Antarctica show clear preferences in relation to environmental conditions (i.e. macroclimate). 306 lichen samples were included in the study, collected along the Ross Sea coast (78[deg]S - 85.5[deg]S) at six climatically different sites. The species compositions as well as the associations of their two dominant symbiotic partners (myco- and photobiont) were set in context with environmental conditions along the latitudinal gradient. Diversity values were nonlinear with respect to latitude, with the highest alpha diversity in the milder areas of the McMurdo Dry Valleys (78[deg]S) and the most southern areas (Durham Point, 85.5[deg]S; Garden Spur, 84.5[deg]S), and lowest in the especially arid and cold Darwin Area (~79.8[deg]S). Furthermore, the specificity of mycobiont species towards their photobionts decreased under more severe climate conditions. The generalist lichen species Lecanora fuscobrunnea and Lecidea cancriformis were present in almost all habitats, but were dominant in climatically extreme areas. Carbonea vorticosa, Lecidella greenii and Rhizoplaca macleanii were confined to milder areas. In summary, the macroclimate is considered to be the main driver of species distribution, making certain species useful as bioindicators of climate conditions and, consequently, for detecting climate change.

scholarly journals Impact of Endophytic Microorganisms on Plants, Environment and Humans

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Dhanya N. Nair ◽  
S. Padmavathy
Keyword(s):  
Nutrient Cycling ◽  
Host Plant ◽  
Environmental Conditions ◽  
Food Industry ◽  
Climatic Conditions ◽  
Plant Tissues ◽  
Symbiotic Association ◽  
Endophytic Microorganisms ◽  
Wide Range ◽  
Almost All

Endophytes are microorganisms (bacteria or fungi or actinomycetes) that dwell within robust plant tissues by having a symbiotic association. They are ubiquitously associated with almost all plants studied till date. Some commonly found endophytes are those belonging to the generaEnterobacter sp.,Colletotrichum sp.,Phomopsis sp.,Phyllosticta sp.,Cladosporium sp.,and so forth. Endophytic population is greatly affected by climatic conditions and location where the host plant grows. They produce a wide range of compounds useful for plants for their growth, protection to environmental conditions, and sustainability, in favour of a good dwelling place within the hosts. They protect plants from herbivory by producing certain compounds which will prevent animals from further grazing on the same plant and sometimes act as biocontrol agents. A large amount of bioactive compounds produced by them not only are useful for plants but also are of economical importance to humans. They serve as antibiotics, drugs or medicines, or the compounds of high relevance in research or as compounds useful to food industry. They are also found to have some important role in nutrient cycling, biodegradation, and bioremediation. In this review, we have tried to comprehend different roles of endophytes in plants and their significance and impacts on man and environment.

Latitude versus local effects on echinoderm assemblages along the Victoria Land coast, Ross Sea, Antarctica

2006 ◽  
Vol 18 (4) ◽  
pp. 655-662 ◽  
Author(s):  
Francesca De Domenico ◽  
Mariachiara Chiantore ◽  
Sabrina Buongiovanni ◽  
Maria Paola Ferranti ◽  
Serena Ghione ◽  
...  
Keyword(s):  
Latitudinal Gradient ◽  
Ross Sea ◽  
Spatial Scales ◽  
Alpha Diversity ◽  
Local Effects ◽  
Assemblage Composition ◽  
Opposite Trend ◽  
Victoria Land ◽  
Oceanographic Conditions ◽  
Broad Scale

Data from two new cruises is used to assess whether latitude plays any role in influencing broad-scale spatial patterns in echinoderm assemblage composition along the Victoria Land coast and the Balleny Islands as a contribution to the Latitudinal Gradient Project. Our results indicate that a latitudinal gradient is influencing assemblage structure in subtle and non-linear ways. The Balleny Islands system is different from the Victoria Land coast, probably because of a different biogeographic origin and current oceanographic conditions. Along the Victoria Land coast, latitude related differences arise when taking into account benthic biodiversity at different spatial scales. Alpha diversity increases from north to south, but beta diversity shows the opposite trend, although not linearly, suggesting the different importance of the iceberg disturbance along the northern Victoria Land coast.

Foliar habit in mistletoe–host associations

Botany ◽  
2017 ◽  
Vol 95 (3) ◽  
pp. 219-229 ◽  
Author(s):  
Gerhard Glatzel ◽  
Hanno Richter ◽  
Mohan Prasad Devkota ◽  
Guillermo Amico ◽  
Sugwang Lee ◽  
...  
Keyword(s):  
South America ◽  
Woody Plants ◽  
Wood Anatomy ◽  
Southern South America ◽  
Main Driver ◽  
Almost All ◽  
The Tropics ◽  
Nutrient Conservation ◽  
Large Vessels ◽  
Host Associations

Foliar habit in parasite–host associations of mistletoes and trees is a neglected aspect in the discussion of foliar habit of woody plants. Almost all of the world’s mistletoe species are evergreen, regardless of the foliar habit of their hosts. Deciduous mistletoes are rare and confined to the northern fringes of Loranthaceae in Eurasia, and to Misodendraceae and the monotypic genus Desmaria (Loranthaceae) in southern South America. There are no deciduous mistletoes in the tropics and subtropics. Based on existing information and hypotheses on foliar habit, we asked why the majority of mistletoe species is evergreen, even on deciduous hosts, and why seasonality is apparently no driver for the evolution of deciduousness in parasite–host systems. We postulate that nutrient conservation is the main driver for evergreenness in mistletoes. Based on our own observations of wood anatomy in the host–haustorium–mistletoe continuum we hypothesize that the phenomenon of deciduousness in northerly Loranthus species is a consequence of interrupted water supply in large vessels after frost. In South America we could not find a consistent correlation between wood anatomy and deciduousness. We assume that deciduousness in these mistletoes evolved long ago in Antarctic forests under climatic and ecological conditions quite different from today.

scholarly journals Potential of Sunflower-Legume Intercropping: A Way Forward in Sustainable Production of Sunflower in Temperate Climatic Conditions

2021 ◽  
Author(s):  
Brankica Babec ◽  
Srđan Šeremešić ◽  
Nada Hladni ◽  
Nemanja Ćuk ◽  
Dušan Stanisavljević ◽  
...  
Keyword(s):  
Red Clover ◽  
Climatic Conditions ◽  
Sustainable Production ◽  
Oilseed Crop ◽  
Common Vetch ◽  
General Belief ◽  
Climate Conditions ◽  
Sole Crop ◽  
Sole Cropping ◽  
Almost All

Changing climate conditions coupled with the transformations of cultivation practices and land use in sole crop-based sunflower production may significantly decline yield stability of this oilseed crop. Given that sunflower takes the third place in the world oilseed market, with 45 million tons per year, and in the fourth place in vegetable oil production, it is necessary to adapt production technologies toward sustainable agriculture. Considering that, the goal of the research was to analyze and beneficial sustainable production technology of sunflower in intercropping systems. A four-year trial was conducted in Serbia’s agroecological rain-fed conditions (45°34’23.2"N 19°86’18.9"E) using a split-plot design. Two oil types and one confectionary sunflower hybrid were intercropped with common vetch, red clover and alfalfa. Analyses showed that intercropping of sunflower with common vetch resulted in the decrease in almost all sunflower trait values. Also, sunflower × alfalfa intercropping provided to be the most appropriate. The yield of NS Gricko and Rimi PR were statistically on the same level with sole cropping, while alfalfa biomass had better results when intercropped with NS Gricko as compared to sole cropping. Concerning the general belief that yields are more stable in intercropping than in sole crop, further research in this respect is needed, in addition to the research of time and method of sowing.

scholarly journals Yield and technological performance of sugarcane cultivars grown under Af climate conditions

2020 ◽  
Vol 41 (1) ◽  
pp. 73
Author(s):  
Augusto Sousa Miranda ◽  
Felipe Nogueira Domingues ◽  
Bruno Spacek Godoy ◽  
Aníbal Coutinho do Rêgo ◽  
Cristian Faturi ◽  
...  
Keyword(s):  
Reducing Sugars ◽  
Agronomic Traits ◽  
Block Design ◽  
High Yield ◽  
Technological Parameters ◽  
Climate Conditions ◽  
Sugarcane Crop ◽  
Randomized Block Design ◽  
Four Blocks ◽  
Almost All

Sugarcane crops are grown in almost all regions of Brazil, in various types of soil and under the influence of different climate conditions, which results in diverse production environments as climate factors directly influence the yield and technological quality of a sugarcane crop. The present study evaluated the agronomic and technological characteristics of sugarcane cultivars grown in Af climate conditions. The agronomic traits (natural matter production and the number, length, and diameter of stalks) and technological attributes (Brix, purity, Pol, reducing sugars, total reducing sugars, moisture, and fiber content) of three sugarcane cultivars, IACSP93-6006, RB83-5486, and SP79-1011, were determined in a three-year experiment with a randomized block design using four blocks and two repetitions per block. The cultivars IACSP93-6006 and SP79-1011 exhibited superior agronomic traits compared to RB83-5486, showing better adaptation to the soil and climate conditions of the study area. However, the technological attributes, which were below the minimum standard levels required by the sugar and ethanol industry, were not statistically different among the studied cultivars. The abundant rainfall and high temperatures, characteristics of an Af climate, were not favorable for sucrose accumulation in the IACSP93-6006, RB83-5486, and SP79-1011 cultivars. Therefore, despite the high yield, sugarcane intended for industrial purposes should not be grown under Af climate conditions, owing to the insufficient technological parameters.

scholarly journals High levels of endemism and local differentiation in the fungal and algal symbionts of saxicolous lecideoid lichens along a latitudinal gradient in southern South America

2020 ◽  
Vol 52 (4) ◽  
pp. 287-303 ◽  
Author(s):  
Ulrike Ruprecht ◽  
Fernando Fernández-Mendoza ◽  
Roman Türk ◽  
Alan M. Fryday
Keyword(s):  
South America ◽  
Latitudinal Gradient ◽  
Molecular Genetic ◽  
Regional Differentiation ◽  
High Mountain ◽  
Polar Regions ◽  
Southern South America ◽  
Climate Conditions ◽  
Algal Symbionts ◽  
Molecular Genetic Data

AbstractSaxicolous, lecideoid lichenized fungi have a cosmopolitan distribution but, being mostly cold adapted, are especially abundant in polar and high-mountain regions. To date, little is known of their origin or the extent of their trans-equatorial dispersal. Several mycobiont genera and species are thought to be restricted to either the Northern or the Southern Hemisphere, whereas others are thought to be widely distributed and occur in both hemispheres. However, these assumptions often rely on morphological analyses and lack supporting molecular genetic data. Also unknown is the extent of regional differentiation in the southern polar regions. An extensive set of lecideoid lichens (185 samples) was collected along a latitudinal gradient at the southern end of South America. Subantarctic climate conditions were maintained by increasing the elevation of the collecting sites with decreasing latitude. The investigated specimens were placed in a global context by including Antarctic and cosmopolitan sequences from other studies. For each symbiont three markers were used to identify intraspecific variation (mycobiont: ITS, mtSSU, RPB1; photobiont: ITS, psbJ-L, COX2). For the mycobiont, the saxicolous genera Lecidea, Porpidia, Poeltidea and Lecidella were phylogenetically re-evaluated, along with their photobionts Asterochloris and Trebouxia. For several globally distributed species groups, the results show geographically highly differentiated subclades, classified as operational taxonomical units (OTUs), which were assigned to the different regions of southern South America (sSA). Furthermore, several small endemic and well-supported clades apparently restricted to sSA were detected at the species level for both symbionts.

scholarly journals Ice Movement Studies on the Skelton Glacier

1961 ◽  
Vol 3 (29) ◽  
pp. 873-878
Author(s):  
Charles R. Wilson ◽  
A. P. Crary
Keyword(s):  
Ross Sea ◽  
Ice Thickness ◽  
Strain Rates ◽  
Shelf Area ◽  
Dry Valleys ◽  
Ice Shelf ◽  
The West ◽  
Ross Ice Shelf ◽  
High Plateau ◽  
Plateau Area

The volume of ice that flows annually from the Skelton Glacier on the west side of the Ross Ice Shelf between the Worcester and Royal Society Ranges was determined during 1958–59 traverse operations to be approximately 791 × 106 m.3 or 712 × 106 m.3 water equivalent. Annual accumulation on the Skelton névé field and small cirque glaciers is estimated to be 1,018 × 106 m.3 water equivalent, but this figure can be reduced to 712 × 106 m.3 by assuming that 30 per cent of the expected accumulation in the lower slopes of the glacier is lost to adjacent areas of the Ross Ice Shelf by katabatic winds. It is evident that little or no contribution to the nourishment of the Skelton Glacier comes from the high plateau area of East Antarctica. It is suggested that this condition exists generally in the western Ross Sea and Ross Shelf area, and is responsible for the existence of the present “dry” valleys in the McMurdo Sound area.Some estimates of local ice regime are made at two sites on the glacier where ice thickness and strain rates are known.

Macrofaunal communities on the continental shelf off Victoria Land, Ross Sea, Antarctica

2011 ◽  
Vol 23 (5) ◽  
pp. 449-455 ◽  
Author(s):  
Peter Rehm ◽  
Rachel A. Hooke ◽  
Sven Thatje
Keyword(s):  
Quantitative Data ◽  
Latitudinal Gradient ◽  
Ross Sea ◽  
Austral Summer ◽  
Benthic Macrofauna ◽  
Weddell Sea ◽  
Victoria Land ◽  
Cluster A ◽  
Taxonomic Groups ◽  
Colonial Organisms

AbstractIn austral summer 2004 benthic macrofauna was sampled along a latitudinal gradient along the northern Victoria Land coast (Ross Sea). An Agassiz trawl was used for semi-quantitative data collection of macrozoobenthos at depths from 84 to 537 m. Multivariate analysis of abundance of higher taxonomic units discriminated between the four sample sites along the latitudinal gradient. A SIMPROF analysis emphasized these geographical clusters, as the samples showed no significant differences within each cluster. A change in community structure with depth was not observed. The dominant taxonomic groups along the Victoria Land coast were Echinodermata (39%), Arthropoda (24%), Polychaeta (14%), and Mollusca (12%), not accounting for colonial organisms. Thus, the overall structure of the benthic community off the Victoria Land coast is comparable to other Antarctic regions and shows a closer relationship to the eastern Weddell Sea shelf, which may be attributable to the extensive impact of grounded ice affecting both areas.

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