scholarly journals Competing for space of aphids

2022 ◽  
Author(s):  
Alijon Xusanov
Keyword(s):  
Host Plants ◽  
Species Selection ◽  
Ecological Niches ◽  
Relative Independence ◽  
Direct Competition ◽  
Different Types

Diversity of ecological niches among aphid entomocenosis increased, most likely, in the process of evolution, due to unsuitability for one or two species selection in the direction of direct competition compared with the advantage of selection in the direction of differentiation niches, reliable provision of resources of different types in terms of maintaining of both species and the relative independence from the competition with other species for resources of host plants....

The causes of extinction

1989 ◽  
Vol 325 (1228) ◽  
pp. 241-252 ◽  
Keyword(s):  
Fossil Record ◽  
Species Turnover ◽  
Rapid Evolution ◽  
Taxonomic Diversity ◽  
Species Selection ◽  
Biotic Factors ◽  
Taxonomic Distribution ◽  
Interacting Species ◽  
Fossil Evidence ◽  
Different Types

A species may go extinct either because it is unable to evolve rapidly enough to meet changing circumstances, or because its niche disappears and no capacity for rapid evolution could have saved it. Although recent extinctions can usually be interpreted as resulting from niche disappearance, the taxonomic distribution of parthenogens suggests that inability to evolve may also be important. A second distinction is between physical and biotic causes of extinction. Fossil evidence for constant taxonomic diversity, combined with species turnover, implies that biotic factors have been important. A similar conclusion emerges from studies of recent introductions of predators, competitors and parasites into new areas. The term ‘species selection’ should be confined to cases in which the outcome of selection is determined by properties of the population as a whole, rather than of individuals. The process has been of only trivial importance in producing complex adaptations, but of major importance in determining the distribution of different types of organisms. An adequate interpretation of the fossil record requires a theory of the coevolution of many interacting species. Such a theory is at present lacking, but various approaches to it are discussed.

scholarly journals Distinct Transcriptional Programs Underlie Differences in Virulence of Isolates on Host Plants in a Fungal Pathogen, Colletotrichum gloeosporioides

2021 ◽  
Vol 12 ◽  
Author(s):  
Wonsu Cheon ◽  
Young Soo Kim ◽  
Kotnala Balaraju ◽  
Younmi Lee ◽  
Hyeok Tae Kwon ◽  
...  
Keyword(s):  
Fungal Pathogens ◽  
Host Plants ◽  
Colletotrichum Gloeosporioides ◽  
Isocitrate Lyase ◽  
Glyoxylate Cycle ◽  
Virulence Gene ◽  
Rna Seq ◽  
Susceptible Host ◽  
Factors Affecting ◽  
Different Types

Susceptible host plants challenged by fungal pathogens can display different types of lesions, which can be attributed to environmental factors affecting the nature of interactions between the host and pathogen. During our survey of apple anthracnose in Korea, two distinct types of disease symptoms, designated as progressive (PS) and static symptoms (SS), were recognized. PS is a typical, rapidly enlarging symptom of apple anthracnose, while SS is a small, dark speck that does not expand further until the harvesting season. Isolation and genotyping of pathogens from disease lesions suggested that all of them belong to Colletotrichum gloeosporioides, a well-known causal agent of apple anthracnose. Two types of isolates were comparable in growth on media, spore germination and appressorium formation, virulence test on fruits at various temperature conditions. Furthermore, they were analyzed at the molecular level by a phylogenetic tree, RNA-seq, and expression of virulence gene. However, the SS isolates were defective in appressorium-mediated penetration into the underlying substratum. RNA-seq analysis of PS and SS isolates showed that distinct transcriptional programs underlie the development of different types of anthracnose symptoms in host plants. One downregulated gene in SS encoded isocitrate lyase is essential for disease development via its involvement in the glyoxylate cycle. It partly explains why SS is less virulent than PS on host plants. Overall, our work challenges the traditional view on the development of different lesion types and provides valuable insights into variations that exist in the pathogen population.

Cryptic diversity in host-associated populations ofTetra pinnatifidae(Acari: Eriophyoidea): What do morphometric, mitochondrial and nuclear data reveal and conceal?

2014 ◽  
Vol 104 (2) ◽  
pp. 221-232 ◽  
Author(s):  
Hao-Sen Li ◽  
Xiao-Feng Xue ◽  
Xiao-Yue Hong
Keyword(s):  
Gene Flow ◽  
Host Plants ◽  
Nuclear Data ◽  
Mite Species ◽  
Cryptic Speciation ◽  
Morphological Divergence ◽  
Cryptic Diversity ◽  
Eriophyoid Mites ◽  
Different Types ◽  
Eriophyoid Mite

AbstractTraditional morphology-based taxonomy of eriophyoid mites (Acari: Eriophyoidea) has been challenged by molecular-based technologies in the detection of cryptic species. However, the implications of such cryptic diversity appear to differ when methods based on different types of data are used. Here, samples of a host-associated eriophyoid mite species,Tetra pinnatifidae, collected from different host plants and localities are evaluated. The congruence of results based on morphometric (32 characters), mitochondrial (16S), and nuclear (28S) data were evaluated and showed a host-associated cryptic diversity dividing this morphospecies into several groups/clades that were morphometrically indistinguishable. In comparison, the 16S data confirmed cryptic speciation and intra-clade host-associated diversity, while 28S did not. In contrast, 28S data revealed potential gene flow between host-associated populations. High mitochondrial divergence, as well as low nuclear and morphological divergence indicated very recent stage of cryptic diversity of this eriophyoid mite.

The earliest beetle identified

2009 ◽  
Vol 83 (6) ◽  
pp. 931-937 ◽  
Author(s):  
Olivier Béthoux
Keyword(s):  
Host Plants ◽  
Ecological Niches ◽  
Seed Plants ◽  
Ecological Preferences ◽  
Environmental Perturbations ◽  
Development Cycle ◽  
Mazon Creek ◽  
Evolutionary Success ◽  
Living Organisms

Holometabolan insects, including beetles (Coleoptera), represent about half of all living organisms. Their development cycle, allowing larvae and adults to exploit distinct ecological niches, is traditionally advocated as a critical adaptation resulting in this extraordinary diversity. Herein I report the occurrence of a beetle from the Pennsylvanian deposit of Mazon Creek (IL, USA). It predates the diversification of Coleoptera by at least 65 million years. This identification supports the view that, early in their history, hyper-diverse extant holometabolan lineages were dominated by Palaeozoic lineages, mostly extinct. End-Permian environmental perturbations might have played an important role in the Triassic radiation of holometabolans. However, it is hypothesized that ecological preferences of holometabolans might have resulted in an earlier diversification of moderate importance, correlating to that of seed plants, their putative host plants. The evolutionary success of ‘holometaboly’ might be the result of a sequence of favorable events.

scholarly journals Diversity Arbuscular Mychorrizal Fungi from Desmodium spp. PT. Cibaliung Sumberdaya, Banten KEANEKARAGAMAN FUNGI MIKORIZA ARBUSKULA (FMA) PADA RHIZOSFER Desmodium spp. ASAL PT. CIBALIUNG SUMBERDAYA, BANTEN

2017 ◽  
Vol 7 (3) ◽  
pp. 188-197
Author(s):  
Sri Muryati ◽  
Irdika Mansur ◽  
Sri Wilarso Budi
Keyword(s):  
Cover Crops ◽  
Host Plants ◽  
Root Colonization ◽  
Sampling Technique ◽  
Soil Samples ◽  
Mining Activity ◽  
Amf Diversity ◽  
Legume Cover Crops ◽  
Key Word ◽  
Different Types

Ecosystem damage as a result of mining activity is very harmful to the environment. One of the strategy repairing the condition of post-mining land is to use legume cover crops, one type of legume cover crops is Desmodium spp., that has ability to form a symbiosis with AMF and rhizobium. The aim of this study was to determine the diversity of AMF from the four types of rhizosphere Desmodium spp. from PT. Cibaliung Sumber Daya, Banten with different types of host plants. The sampling technique of soil and roots were done by non propotional method. Soil samples were trapped with some types of host plants. Spores were isolated by wet-seaving and decanting technique, then the density of spores was measured and identified. The results showed an increasing number of spore and diversity of AMF. The number of spore before trapped was 10-89 spores per 20 g soil then increased to 16-114 spores per 20 g soil. While the AMF diversity before trapped found only 9 type of spores, consists of 8 type Glomus and 1 type Acaulospora. After trapped increased to 26 spores type AMF consists of 23 type of Glomus and 3 type of Acaulospoara. The root colonization was in range of 22.2 - 95.5%.Key word: Desmodium spp. , Cibaliung, Cover crops.

scholarly journals Occurrence of galls in Microgramma mortoniana (Polypodiopsida: Polypodiaceae) from a subtropical forest, Brazil

Lilloa ◽  
2020 ◽  
pp. 72-80
Author(s):  
Carlos R. Lehn ◽  
Marcelo D. Arana ◽  
Gerson Azulim Müller ◽  
Edmilson Bianchini
Keyword(s):  
Host Plants ◽  
Deciduous Forest ◽  
Morphological Characteristics ◽  
Normal Growth ◽  
Plant Tissues ◽  
Sampling Effort ◽  
Forest Fragment ◽  
Narrow Host Range ◽  
The Family ◽  
Different Types

The galls are structures formed of plant tissues in response to the activity of different types of organisms, especially by insects. As a consequence of an intimate relationship with their host plants, most of these insects have a very narrow host range. In this study we report the occurrence of galls on Microgramma mortoniana. Morphological characteristics and field observations are presented. The study was carried out in a seasonal semi-deciduous forest fragment, located in the São João do Oeste municipality, Santa Catarina, southern Brazil. The galls present a fusiform shape and similar indument to the rhizome, in a higher density. In the region of occurrence of the galls, a widening of the rhizome was observed, reaching an average of 9 mm (±1mm), whereas in a rhizome with normal growth the width is 4 (±1 mm). The gall is unicameral, with the following dimensions: 7 mm (±1 mm) x 2 (±1 mm). The larvae observed into the chamber are about 0,7 mm long, being representative of the family Tortricidae (Lepidoptera). In all cases, the rhizomes with galls do not presented continuous development and, consequently, the rhizome has its limit of growth defined by the occurrence of the gall. The results indicate that a greater sampling effort of fern galls in the Neotropics is needed, contributing to the knowledge about the distribution of the galls on ferns lineages.

scholarly journals A preliminary study of development of the buccal apparatus in Pomacentridae (Teleostei, Perciformes)

2006 ◽  
Vol 56 (3) ◽  
pp. 351-372 ◽  
Author(s):  
◽  
◽  
Keyword(s):  
The Other ◽  
Ecological Niches ◽  
Feeding Apparatus ◽  
Suction Feeding ◽  
Skeletal Structures ◽  
Other Hand ◽  
Jaw Opening ◽  
Different Types ◽  
Preliminary Study

AbstractThis study compares, in five species of Pomacentridae (Chromis viridis, Dascyllus flavicaudus, Chrysiptera glauca, Pomacentrus pavo, Plectroglyphidodon lacrymatus), the changes in cephalic skeletal structures between settling larvae and adults living on the reef. Variations were studied in the suspensorium, the opercle, the mandible, the premaxillary bone and the teeth. Comparisons of the feeding apparatus enabled two different types of feeding to be distinguished in adults: suction feeding and grazer sucking. Adult C. viridis and D. flavicaudus have a high suspensorium, a well-rounded mouth during jaw opening and caniniform teeth. These two species can be considered to be suction feeders. On the other hand, adult C. glauca, P. pavo and P. lacrymatus have less developed suspensoria, opercles and ascending process of the premaxillar, and present incisiform teeth. These three species appear to be grazer suckers. However, the larvae of all five species present an unimodal way of feeding, defined as ram-suction. Differences between larvae and adults appear clearly to be related to their ecology. The increasing variation presented in feeding apparatus during the settlement phase could be linked to diversification leading to occupancy of different ecological niches.

scholarly journals Galls and gall makers in plants from the Pé-de-Gigante Cerrado Reserve, Santa Rita do Passa Quatro, SP, Brazil

2006 ◽  
Vol 66 (1b) ◽  
pp. 357-369 ◽  
Author(s):  
M. V. Urso-Guimarães ◽  
C. Scareli-Santos
Keyword(s):  
Host Plant ◽  
Plant Species ◽  
Host Plants ◽  
The Body ◽  
Flower Buds ◽  
First Report ◽  
Host Plant Species ◽  
Body Of Knowledge ◽  
Different Types ◽  
The Relationship

Thirty-six morphologically different types of galls were obtained in leaves, leaflets, veins, petioles, stems, tendrils and flower buds from twenty-five species of plants in the Pé-de-Gigante Reserve, municipality of Santa Rita do Passa Quatro, state of São Paulo, Brazil. The host plant species belong to the closely related families Anacardiaceae, Annonaceae, Asteraceae, Bignoniaceae, Caryocaraceae, Erythroxylaceae, Fabaceae, Malpighiaceae, Melastomataceae, Myrtaceae, Ochnaceae, Polygalaceae, Sapindaceae, Sapotaceae, and Smilacaceae. The most common gall makers included Cecidomyiidae (Diptera), Pteromalidae (Hymenoptera) and Diaspididae (Sternorrhyncha-Hemiptera). This is the first report of galls found in the following plant genera: Gochnatia (Asteraceae), Distictela (Bignoniaceae), Banisteriopsis (Malpighiaceae), Ouratea (Ochnaceae), and Bredemeyera (Polygalaceae). The results of this work contribute to the body of knowledge about the relationship among host plants, gall makers, and the gall morphology of Pé-de-Gigante Cerrado Reserve.

Relationships between periglacial features and vegetation development in Victoria Land, continental Antarctica

2010 ◽  
Vol 22 (6) ◽  
pp. 703-713 ◽  
Author(s):  
N. Cannone ◽  
M. Guglielmin
Keyword(s):  
Ground Surface ◽  
The Arctic ◽  
Ecological Niches ◽  
Vegetation Patterns ◽  
Patterned Ground ◽  
Vegetation Development ◽  
Victoria Land ◽  
Continental Antarctica ◽  
Different Types ◽  
The Antarctic

AbstractThe relationships between vegetation patterns and periglacial features and their underlying ecology are still poorly understood and lack specific investigations in Antarctica. Here we present the results of vegetation colonization of different types of sorted patterned ground and gelifluction features (lobes and terracettes) at four sites in northern Victoria Land. This paper aims to understand the relationships between vegetation and the most widespread periglacial features in Victoria Land, discuss the role of periglacial features and vegetation in determining the ground surface temperature, and assess whether periglacial features provide ecological niches for vegetation colonization and development. Vegetation patterns are influenced by the feature type, mainly relating to patterned ground and debris island versus gelifluction features. The relations between vegetation and the periglacial features investigated in continental Antarctic are similar to those described for the Arctic, although in this part of the Antarctic vegetation is exclusively composed of cryptogams. Frost heave, ground texture and relief associated with different types of periglacial features provide a range of ecological niches sustaining vegetation biodiversity. Our data confirm the importance of periglacial features in shaping flora and vegetation biodiversity, as previously assessed only for the soil fauna in continental Antarctic.

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