Search results for "Systematics"
showing 10 items of 6702 documents
Composition and allelopathic effect of essential oils of two thistles: Cirsium creticum (Lam.) D.�Urv. ssp. triumfetti (Lacaita) Werner and Carduus n…
2007
Abstract Cirsium and Carduus are two of the main genera of true thistles. Different species in these genera share a quantity of secondary metabolites and have interesting ecological properties. The essential oils of two species, Cirsium creticum and Carduus nutans, were analysed, showing the presence as main compounds of 4-ethyl guaiacol (15%), hexadecanoic acid (10.6%), (E)-β-damascenone (7.8%), dihydroactinidiolide (6.0%) and 4-vinyl guaiacol (4.5%) for C. creticum and hexadecanoic acid (18.6%), hexahydrofarnesylacetone (7.8%), heptacosane (5.9%), 4-vinyl guaiacol (5.8%), pentacosane (3.8%) and eugenol (3.6%) for C. nutans. The oils were evaluated at different doses for their effect on ge…
A screening of five Bacillus thuringiensis Vip3A proteins for their activity against lepidopteran pests
2014
Five Bacillus thuringiensis Vip3A proteins (Vip3Aa, Vip3Ab, Vip3Ad, Vip3Ae and Vip3Af) and their corresponding trypsin-activated toxins were tested for their toxicity against eight lepidopteran pests: Agrotis ipsilon, Helicoverpa armigera, Mamestra brassicae, Spodoptera exigua, Spodoptera frugiperda, Spodoptera littoralis, Ostrinia nubilalis and Lobesia botrana. Toxicity was first tested at a high dose at 7 and 10. days. No major differences were found when comparing protoxins vs. trypsin-activated toxins. The proteins that were active against most of the insect species were Vip3Aa, Vip3Ae and Vip3Af, followed by Vip3Ab. Vip3Ad was non-toxic to any of the species tested. Considering the res…
Comparative analysis of leaf shape development inEschscholzia californicaand other Papaveraceae-Eschscholzioideae
2011
Dissected leaves in Papaveraceae-Eschscholzioideae have an architecture frequently encountered in the basal eudicot clade Ranunculales that could represent an ancestral condition for eudicots. Developmental morphology of foliage leaves was investigated using scanning electron microscopy and focusing on primordium formation activity (primary morphogenesis) at the leaf margin. Eschscholzia californica, E. lobii, and Hunnemannia fumariaefolia had a polyternate-acropetal mode of leaf dissection. Segment formation continued around the whole leaf blade periphery. Differences in mature leaf architecture was traced to variations in regional blastozone activity and duration. Epidermal cell size meas…
Relation of fruit color, elongation, hardness, and volume to the infestation of olive cultivars by the olive fruit fly, Bactrocera oleae
2012
The susceptibility of olive cultivars to the olive fruit fly, Bactrocera oleae (Rossi) (Diptera: Tephritidae), has seldom been studied. This article examines factors associated with olive fruit fly infestation of 16 commonly planted Sicilian olive cultivars. Total infestation data were simultaneously correlated with categorical and quantitative factors using ordinal logistic regression. When all factors were included in the analysis, year, sampling date, cultivar, and fruit color were highly significant, but the quantitative factors fruit volume, fruit elongation, and fruit hardness were not. When the analysis was repeated excluding cultivar, all quantitative factors were significant, and e…
Orthotrichum Norrisii (Orthotrichaceae), A New Epiphytic Californian Moss
2008
Abstract A new Orthotrichum species, O. norrisii, is described from California. The new taxon is recognized by a unique combination of sporophytic characters: capsule narrowly cylindrical and not contracted below mouth when dry, exothecial bands narrow and formed by 2(–3) cell rows, peristome with eight pairs of exostome teeth and eight endostome segments, stomata cryptopore and located in the lower part of the urn, lid plane and rostrate and vaginula hairy. Widely distributed throughout California, the new taxon has been overlooked and confused with O. tenellum.
Mtha1, a Plasma Membrane H+-ATPase Gene fromMedicago truncatula,Shows Arbuscule-Specific Induced Expression in Mycorrhizal Tissue
2002
: Transport processes between plant and fungal cells are key elements in arbuscular mycorrhiza (AM), where H+-ATPases are considered to be involved in active uptake of nutrients from the symbiotic interface. Genes encoding H+-ATPases were identified in the genome of Medicago truncatula and three cDNA fragments of the H+-ATPase gene family (Mtha1 - 3) were obtained by RT-PCR using RNA from M. truncatula mycorrhizal roots as template. While Mtha2 and Mtha3 appeared to be constitutively expressed in roots and unaffected by AM development, transcripts of Mtha1 could only be detected in AM tissues and not in controls. Further analyses by RT-PCR revealed that Mtha1 transcripts are not detectable …
Melanin-based colour polymorphism signals aggressive personality in nest and territory defence in the tawny owl (Strix aluco)
2013
Nest and territory defence are risky and potentially dangerous behaviours. If the resolution of life history trade-offs differs between individuals, the level of defence may also vary among individuals. Because melanin-based colour traits can be associated with life history strategies, differently coloured individuals may display different nest and territory defence strategies. We investigated this issue in the colour polymorphic tawny owl (Strix aluco) for which plumage varies from dark to light reddish melanic. Accordingly, we found that (1) our presence induced a greater response (flying around) from dark-coloured than light-coloured females and (2) dark reddish males suffered lower nest…
Las hormigas (Hymenoptera, Formicidae) asociadas a pulgones (Hemiptera, Aphididae) en la provincia de Valencia
2002
Twenty-six species of ants associated with aphids, belonging to twelve genera, are collected. Three subfamilies are identified, being the Formicinae the more represented about number of samples, genera and species. On the other hand, <i>Lasius niger</i> has been the species that is found with a more number of aphids (fifty eight species), and it seems to be the ant with a more capacity to establish associations with the different species of aphids. 224 different associations between the ants and the aphids are established and 164 of them are not recorded in the bibliography consulted for Spain.<br><br>Se han recogido veintiséis especies de hormigas asociadas a pulgon…
Female choice in the kestrel under different availability of mating options
1992
Abstract Mate choice in relation to its fitness consequences on females was studied in kestrels, Falco tinnunculus , in western Finland. The breeding season is short with rapidly declining prospects of successful breeding, suggesting that females should make their mating decision quickly. On average, males arrived a few days before females, but late males arrived much later than early females. Pairs were usually formed within 2 days of male arrival, and only early males were available to early females. Options for female choice differed considerably in years of different kestrel density. In a good vole year, 1988, females had many males to choose from, but in poor vole years, 1989 and 1990,…
MORPHOLOGICAL AND ANATOMICAL STRUCTURE OF GALLS IN GENISTA FLORIDA L. SUBSP. POLYGALIPHYLLA (BROT.) COUTHINO (LEGUMINOSAE)
1999
This paper describes the morphology and anatomy of a structure which appears in the floral racemes of Genista florida L. subsp. polygaliphylla (Brot.) Couthino. In this subspecies the floral racemes have a small number of flowers. This structure develops quite frequently in this taxon, which is found in the northwest of the Iberian Peninsula, but never in Genista florida subsp. florida. Its morphology is simple: bottle-shaped, wide at the base and elongated to a narrow peak at the upper extreme. Anatomical examination shows that these structures have a close similarity to flowers. Since they develop by the oviposition of one insect of the Cecidomyiidae family in the floral buds, they can be…