Morphological Characters Research Papers - Academia.edu (original) (raw)
- by D. Stengel and +1
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- Genetics, Plant Biology, Seasonality, North Atlantic
The biology of Spodoptera cosmioides (Walk.) was studied on four natural hosts (onion leaves, castor oil plant, soy cv. Embrapa 48 and bean cv. Carioca). The duration and viability of immature phases and total cycle, instar number, pupals... more
The biology of Spodoptera cosmioides (Walk.) was studied on four natural hosts (onion leaves, castor oil plant, soy cv. Embrapa 48 and bean cv. Carioca). The duration and viability of immature phases and total cycle, instar number, pupals weight, sexual ratio, percentage of deformed adults and adults not released of pupal beg, adultsí longevity, fecundity and eggs viability were evaluated.
In this review, reasons for the slow progress in development of drought resistant cultivars for rainfed lowland rice are considered first. Recent advances in screening methods for development of drought resistant cultivars from mostly our... more
In this review, reasons for the slow progress in development of drought resistant cultivars for rainfed lowland rice are considered first. Recent advances in screening methods for development of drought resistant cultivars from mostly our research in Thailand in the 1990s, are then described for drought that develops early or late in the wet-season. There now appears to be a good prospect for developing drought resistant cultivars that produce higher yield than existing cultivars when drought develops late in the wet-season. Appropriate phenology to escape late-season drought and high potential yield under well-watered conditions are important characters for cultivars adapted to rainfed lowland conditions. In addition, ability to maintain higher leaf water potential when drought develops late in the season is another desirable character. Maintenance of leaf water potential just prior to flowering is associated with higher panicle water potential, reduced delay in flowering time, and reduced spikelet sterility, and hence contributes to higher yield. Genotypes that are adapted to areas of late-season drought should also have high harvest index, intermediate height and rather small total dry matter compared to existing traditional cultivars, under well-watered conditions. This combination of characters would ensure high potential yield under favourable conditions and also contribute to resistance against late-season drought. Screening against early-season drought that develops during the vegetative stage is more difficult, as the genotype’s ability to recover from the stress appears more important than drought tolerance during the stress period.Other than appropriate phenology, high potential yield and ability to maintain high leaf water potential, no specific physiological and morphological characters appear to contribute directly to higher yield under drought conditions in rainfed lowland rice in Thailand, where drought develops rather rapidly due to the prevailing coarse textured soils. It is thus appropriate to develop a breeding program that is primarily based on selection for grain yield. There are large genotype by environment interactions for yield in rainfed lowland rice and hence it is important that genotypes are selected for yield under appropriate target environments. Addition of a drought screening program that is conducted in the field in the wet-season to the overall breeding program would enhance the opportunity to select for drought resistance within the breeding materials and increase the chance of developing high yielding cultivars adapted to the drought-prone rainfed lowland environments.
Two new species, Leicacandona pinkajartinyi sp. nov. and L. jula sp. nov., are described from the Great Sandy Desert, Western Australia. Both species have reduced posterior claws on the caudal ramus, but differ in carapace shape and the... more
Two new species, Leicacandona pinkajartinyi sp. nov. and L. jula sp. nov., are described from the Great Sandy Desert, Western Australia. Both species have reduced posterior claws on the caudal ramus, but differ in carapace shape and the length of setae and number of segments on the second and third thoracopods. A cladistic tree based on 27 morphological characters and a tree based on geographic latitudes and longitudes of the localities where Leicacandona species have been collected so far were constructed. These two cladograms do not correspond completely, although some similarities exist. The results obtained here agree with those obtained for some other subterranean animals in Australia, and they are understood as independent colonizations of subterranean waters by a couple of widespread surface water species.
Ranghoo, V.M., Hyde, K.D., Liew, E.C.Y and Spatafora, lW. (1999). Family placement of Ascotaiwania and Ascolacicola based on DNA sequences from the large subunit rRNA gene. Fungal Diversity 2: 159-168. The family placement of Ascotaiwania... more
Ranghoo, V.M., Hyde, K.D., Liew, E.C.Y and Spatafora, lW. (1999). Family placement of Ascotaiwania and Ascolacicola based on DNA sequences from the large subunit rRNA gene. Fungal Diversity 2: 159-168. The family placement of Ascotaiwania and Ascolacicola have been analysed by using partial sequences of the large subunit ribosomal DNA (LSU rDNA). The 5' end of the LSU rDNA was included in the analysis, which consisted of species from the Diaporthales, Halosphaeriales, Hypocreales, Microascales, Sordariales and Xylariales. The resulting trees indicate that Ascotaiwania is unrelated to the Annulatascaceae. A close relationship between the anamorphs of the different species of Ascotaiwania were found and they were closely related to Monotosporella setosa, the type species of Monotosporella. Based on morphological characters, production of different anamorphs, and the sequence analysis, it was found that Ascolacicola differs from Ascotaiwania. Ascolacicola was most closely related t...
Ceuthophilus spp. (Orthoptera: Rhaphidophoridae) in two subgenera (Ceuthophilus and Geotettix) were examined phylogenetically, morphologically, and biogeographically in order to improve our understanding of these species that carry... more
Ceuthophilus spp. (Orthoptera: Rhaphidophoridae) in two subgenera (Ceuthophilus and Geotettix) were examined phylogenetically, morphologically, and biogeographically in order to improve our understanding of these species that carry nutrients into caves and are thus closely tied to rare and endangered troglobites in central Texas. Crickets were collected from 43 caves across central Texas, and outgroup taxa were collected in west Texas,
- by Jean Krejca and +1
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- Genetics, Principal Component Analysis, Life history, Mitochondrial DNA
- by Ellen Larsson and +1
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- Evolutionary Biology, Genetics, Zoology, Molecular Evolution
Homology is an essential idea of biology, referring to the historical continuity of characters, but it is also conceptually highly elusive. The main difficulty is the apparently loose relationship between morphological characters and... more
Homology is an essential idea of biology, referring to the historical continuity of characters, but it is also conceptually highly elusive. The main difficulty is the apparently loose relationship between morphological characters and their genetic basis. Here I propose that it is the historical continuity of gene regulatory networks rather than the expression of individual homologous genes that underlies the homology of morphological characters. These networks, here referred to as 'character identity networks', enable the execution of a character-specific developmental programme.
- by Dirk U Bellstedt and +1
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- Evolutionary Biology, Genetics, Zoology, Geography
A reexamination of the French Compsognathus corallestris, from the Portlandian lithographic limestones of the Tithonian of southern France, provides new cranial and postcranial information crucial for a better understanding of the taxon... more
A reexamination of the French Compsognathus corallestris, from the Portlandian lithographic limestones of the Tithonian of southern France, provides new cranial and postcranial information crucial for a better understanding of the taxon Compsognathus. The French ...
Recently, the phylogenetic placement of the African slender snouted crocodile, Crocodylus cataphractus, has come under scrutiny and herein we address this issue using molecular and morphological techniques. Although it is often recognized... more
Recently, the phylogenetic placement of the African slender snouted crocodile, Crocodylus cataphractus, has come under scrutiny and herein we address this issue using molecular and morphological techniques. Although it is often recognized as being a “basal” form, morphological studies have traditionally placed C. cataphractus within the genus Crocodylus, while molecular studies have suggested that C. cataphractus is very distinct from other Crocodylus. To address the relationship of this species to its congeners we have sequenced portions of two nuclear genes (C-mos 302 bp and ODC 294 bp), and two mitochondrial genes (ND6-tRNAglu-cytB 347 bp and control region 457 bp). Analyses of these molecular datasets, both as individual gene sequences and as concatenated sequences, support the hypothesis that C. cataphractus is not a member of Crocodylus or Osteolaemus. Examination of 165 morphological characters supports and strengthens our resurrection of an historic genus, Mecistops (Gray 1844) for cataphractus.
There are as many as 300 New World lupin species, distributed from Alaska to the extreme south of South America. Only one species among these, Lupinus mutabilis has achieved crop status while several other species have been used as... more
There are as many as 300 New World lupin species, distributed from Alaska to the extreme south of South America. Only one species among these, Lupinus mutabilis has achieved crop status while several other species have been used as ornamentals or for land rehabilitation. L. mutabilis has considerable potential as a high protein and oil legume and it is phylogenetically
Ceratocystis canker, which is caused by the fungus Ceratocystis fimbriata Ellis et Halsted, is one of the most severe diseases of the common fig (Ficus carica L.). In contrast, the wild fig species F. erecta Thunb. is resistant to this... more
Ceratocystis canker, which is caused by the fungus Ceratocystis fimbriata Ellis et Halsted, is one of the most severe diseases of the common fig (Ficus carica L.). In contrast, the wild fig species F. erecta Thunb. is resistant to this fungus. We performed interspecific hybridization between the common fig (seed parent) and F. erecta (pollen parent) through artificial pollination. Even though hybrid seeds showed high germination rates, the seedling survival rates were low. All of the seedlings contained the expected simple sequence repeat (SSR) alleles from both common fig and F. erecta at each of the three loci tested, thus confirming the parent–offspring relationships of the interspecific hybrids. The leaf morphological characters of hybrid seedlings were intermediate between those of the parents. Cuttings of cultivars of common fig, F. erecta, and hybrid seedlings were inoculated with C. fimbriata by direct wounding of the shoot. All of the common fig cultivars tested withered and died within 10 weeks. Leaves and shoots of the hybrids and F. erecta were healthy 100 days after inoculation. Our results suggest that interspecific hybridization between the common fig and the wild species F. erecta is a breakthrough in the breeding of a new fig rootstock source with resistance to Ceratocystis canker.
Inocybe tubarioides is a rarely collected or recognized agaric with an unusual combination of ecological and morphological characters for this genus, namely a lignicolous habit and a strongly hygrophanous pileus. The species is known only... more
Inocybe tubarioides is a rarely collected or recognized agaric with an unusual combination of ecological and morphological characters for this genus, namely a lignicolous habit and a strongly hygrophanous pileus. The species is known only from eastern North America and is reported here for the first time from states in New England and Canada. A taxonomic description is provided, including the first photographic record of the species and discussion of its evolutionary history. Based on molecular phylogenetic analysis the species is most closely related with significant measures of statistical support to two other narrowly endemic species of Inocybe: one also from eastern North America (I. tahquamenonensis) and another from northern Europe (I. relicina), the latter of which is the type of the genus Inocybe. These three species constitute the clade that corresponds with section Inocybe. Inocybe tubarioides est un Agaric rarement signalé, présentant une combinaison inhabituelle de caractéristiques écologiques et morphologiques, en particulier l’habitat lignicole et le chapeau fortement hygrophane. Cette espèce n’est connue que de la façade orientale de l’Amérique du Nord, et est signalée ici pour la première fois en Nouvelle-Angleterre et Canada. Une description est fournie, accompagnée pour la première fois d’une photographie, et d’une discussion quant à son histoire évolutive. D’après des analyses moléculaires phylogénétiques soutenues par des mesures statistiques significatives, cette espèce est très étroitement apparentée à deux autres espèces endémiques, l’une également connue de l’Est de l’Amérique du Nord (I. tahquamenonensis), l’autre d’Europe du Nord (I. relicina) qui se trouve être le type du genre Inocybe. Ces trois espèces constituent la clade: section Inocybe.
- by Gregg F. Gunnell and +1
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- Evolutionary Biology, Genetics, Zoology, Molecular Evolution
- by Xiaoya Ma
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- Zoology, Paleontology, China, Phylogeny