Factors that limit the emergence and establishment of the related aliens Senecio inaequidens and Senecio pterophorus and the native Senecio malacitanus in Mediterranean climate

2004 ◽  
Vol 82 (9) ◽  
pp. 1346-1355 ◽  
Author(s):  
Hèctor Garcia-Serrano ◽  
Josep Escarré ◽  
F Xavier Sans
Keyword(s):  
Water Availability ◽  
Mediterranean Climate ◽  
Adult Stage ◽  
Habitat Type ◽  
Water Addition ◽  
Experimental Conditions ◽  
Dramatic Effect ◽  
Annual Grassland ◽  
Invasive Capacity ◽  
Senecio Inaequidens

Three series of seed addition experiments in natural sites and in common experimental conditions are described to compare the effect of disturbance, water availability, and habitat type on the emergence and establishment of the two alien congeners Senecio inaequidens D.C. and Senecio pterophorus D.C. and the native Senecio malacitanus Huter. The emergence of the three species was favored by disturbance, while establishment was enhanced by water availability. Habitat also had a dramatic effect on emergence, with more seedlings germinating under the shrubs and in the forest. However, only the plants that emerged in the open annual grassland survived until the adult stage, some of which flowered, mostly S. inaequidens. The emergence of the alien S. pterophorus was lower than that of the other species, but once established it produced significantly more biomass than the others. The effect of disturbance and water availability on emergence and establishment does not explain the differences in invasive capacity between the two aliens and the native; however, some traits, such as the biomass production of S. pterophorus and the early flowering of S. inaequidens, can contribute to the capacity of the two aliens to colonize new habitats.Key words: Senecio, alien invasive, emergence, disturbance, water addition, seed or site limitation.

THE IMMATURE STAGES OF PTYCHOPTERA LENIS LENIS (DIPTERA: PTYCHOPTERIDAE) WITH NOTES ON THEIR BIOLOGY

1973 ◽  
Vol 105 (8) ◽  
pp. 1091-1099 ◽  
Author(s):  
I. D. Hodkinson
Keyword(s):  
Life Cycle ◽  
Water Depth ◽  
Adult Stage ◽  
Atmospheric Oxygen ◽  
Adult Emergence ◽  
Fourth Instar ◽  
Immature Stages ◽  
Experimental Conditions ◽  
Marginal Areas ◽  
Pharate Adult

AbstractThe four larval instars and the pupa of Ptychoptera lenis lenis Osten Sacken are described. Instars 2 to 4 are very similar morphologically but instar 1 is markedly different. Both a pharate pupal and a pharate adult stage were observed. Larvae are found in stagnant marginal areas of ponds where water depth does not exceed 4 cm and where benthic deposits of plant detritus exceed 8 cm. Fourth instar larvae, under experimental conditions, survived up to 45 days without contact with atmospheric oxygen but development was arrested. P. lenis has a 1 year life cycle with an extended adult emergence season from late May to the end of July.

The influence of population density on the number of eggs laid by females of Cardiaspina albitextura (Psyllidae)

1963 ◽  
Vol 11 (2) ◽  
pp. 190 ◽  
Author(s):  
LR Clark
Keyword(s):  
Egg Production ◽  
Adult Stage ◽  
Limiting Factor ◽  
Severe Damage ◽  
Population Densities ◽  
Experimental Conditions ◽  
Nymphal Development ◽  
The Mean ◽  
Peak Abundance ◽  
Oviposition Sites

Field observations and experiments suggest that crowding during the period of nymphal development does not greatly affect the mean number of eggs laid by Cardiaspina albitextura females. Under experimental conditions, crowding in the adult stage on foliage undamaged by nymphs resulted in reduction of the mean number of eggs laid, the supply of favourable food being probably the limiting factor. In association with increase in the number of adults per shoot, mean egg production declined at a progressively decreasing rate. At the highest population densities tested, the mean number of eggs laid per female was approximately one-third to one-fifth of the number laid by uncrowded females. Both at low and high population densities, the mean number of eggs laid per female on previously unoccupied foliage was about twice as high as on foliage which had been occupied previously by numerous other adults of the same psyllid generation. At times of peak abundance in areas of outbreak, the foliage damage caused during the period of nymphal development greatly limits both the quantity of favourable food and the number of oviposition sites available when C. albitextura reaches the adult stage. The experimental results suggest that the crowding of adults which occurs on the small amount of foliage that escapes very severe damage by nymphs contributes towards the observed limitation of egg production. However, the scattered distribution of such foliage and the poor dispersal powers of C. albitextura females probably play a more important part in determining the very low mean number of eggs laid per female reaching the adult stage. It appears that many females fail to find favourable foliage and consequently lay scarcely any eggs.

scholarly journals Amblyomma nodosum (Neumann, 1899): observations on life cycle under laboratory conditions

2015 ◽  
Vol 24 (3) ◽  
pp. 357-360 ◽  
Author(s):  
Michele da Costa Pinheiro ◽  
Elizabete Captivo Lourenço ◽  
Iwine Joyce Barbosa de Sá-Hungaro ◽  
Kátia Maria Famadas
Keyword(s):  
Life Cycle ◽  
Relative Humidity ◽  
Environmental Conditions ◽  
Oryctolagus Cuniculus ◽  
Adult Stage ◽  
Immature Stages ◽  
Experimental Conditions ◽  
Laboratory Conditions ◽  
Natural Hosts

The natural hosts of Amblyomma nodosum in the immature stages are a variety of birds and the anteater in the adult stage. However, so far no data have been published about this tick’s life cycle. To fill this gap, a record was made of its development under laboratory conditions. All the procedures were controlled in a BOD chamber set at 27±1 °C and 80±10% relative humidity and scotophase. The parasitic stages were raised on rabbits (Oryctolagus cuniculus Linnaeus, 1758), from which more than 50% of larvae and nymphs were recovered, although only a small portion performed ecdysis. The adults did not fixed on the rabbits, which suggests that the experimental conditions were unsuitable for the requirements of this species. The data obtained here indicate that A. nodosum is highly dependent on its host and environment whereas under laboratory conditions and host chosen for the study was not obtained satisfactory results and new studies with different hosts and new environmental conditions should be elaborated.

scholarly journals Wet Meadow Plant Communities of the Alliance Trifolion pallidi on the Southeastern Margin of the Pannonian Plain

Water ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 381
Author(s):  
Andraž Čarni ◽  
Mirjana Ćuk ◽  
Igor Zelnik ◽  
Jozo Franjić ◽  
Ružica Igić ◽  
...  
Keyword(s):  
Numerical Analysis ◽  
Plant Communities ◽  
Mediterranean Climate ◽  
Management Practices ◽  
Vegetation Type ◽  
Habitat Type ◽  
Wet Meadow ◽  
Northern Border ◽  
Pannonian Plain ◽  
The Mediterranean

The article deals with wet meadow plant communities of the alliance Trifolion pallidi that appear on the periodically inundated or waterlogged sites on the riverside terraces or gentle slopes along watercourses. These plant communities are often endangered by inappropriate hydrological interventions or management practices. All available vegetation plots representing this vegetation type were collected, organized in a database, and numerically elaborated. This vegetation type appears in the southeastern part of the Pannonian Plain, which is still under the influence of the Mediterranean climate; its southern border is formed by southern outcrops of the Pannonian Plain and its northern border coincides with the influence of the Mediterranean climate (line Slavonsko Gorje-Fruška Gora-Vršačke Planine). Numerical analysis established four plant associations—Trifolio pallidi–Alopecuretum pratensis, Ventenato dubii–Trifolietum pallidi, Ranunculo strigulosi–Alopecuretum pratensis, and Ornithogalo pyramidale–Trifolietum pallidi. Each association was elaborated in detail: diagnostic plant species, nomenclature, geographical distribution, climatic and ecological conditions, and possible division into subassociations. Results are presented in a distribution map, figures resulting from numerical analysis, and a synoptic table. The hydrological gradient was found as the most important factor shaping the studied plant communities. The article also brings new field data on this vegetation type, which has not been sampled for decades and is in process of evaluation to be included as a special habitat type in the Habitat Directive.

scholarly journals Co-Processed Olive Oils with Thymus mastichina L.—New Product Optimization

Life ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1048
Author(s):  
Fátima Peres ◽  
Marta Roldão ◽  
Miguel Mourato ◽  
Luisa L. Martins ◽  
Suzana Ferreira-Dias
Keyword(s):  
Raw Materials ◽  
Virgin Olive Oil ◽  
Chemical Characterization ◽  
Quality Criteria ◽  
New Product ◽  
Major Fatty Acid ◽  
Chemical Quality ◽  
Water Addition ◽  
Experimental Conditions ◽  
Phenolic Contents

Olive co-processing consists of the addition of ingredients either in the mill or in the malaxator. This technique allows selecting the type of olives, the ingredients with the greatest flavoring and bioactive potential, and the technological extraction conditions. A new product—a gourmet flavored oil—was developed by co-processing olives with Thymus mastichina L. The trials were performed using overripe fruits with low aroma potential (cv. ‘Galega Vulgar’; ripening index 6.4). Experimental conditions were dictated by a central composite rotatable design (CCRD) as a function of thyme (0.4−4.6%, w/w) and water (8.3−19.7%, w/w) contents used in malaxation. A flavored oil was also obtained by adding 2.5% thyme during milling, followed by 14% water addition in the malaxator (central point conditions of CCRD). The chemical characterization of the raw materials, as well as the analysis of the flavored and unflavored oils, were performed (chemical quality criteria, sensory analysis, major fatty acid composition, and phenolic compounds). Considering chemical quality criteria, the flavored oils have the characteristics of “Virgin Olive Oil” (VOO), but they cannot have this classification due to legislation issues. Flavored oils obtained under optimized co-processing conditions (thyme concentrations > 3.5−4.0% and water contents varying from 14 to 18%) presented higher phenolic contents and biologic value than the non-flavored VOO. In flavored oils, thyme flavor was detected with high intensity, while the defect of “wet wood”, perceived in VOO, was not detected. The flavored oil, obtained by T. mastichina addition in the mill, showed higher oxidative stability (19.03 h) than the VOO and the co-processed oil with thyme addition in the malaxator (14.07 h), even after six-month storage in the dark (16.6 vs. 10.3 h).

Life history and morphological variation in intraspecific seeder and resprouter populations of two species from rock outcrop vegetation in north-east New South Wales

2011 ◽  
Vol 59 (3) ◽  
pp. 197 ◽  
Author(s):  
Andrew Benwell ◽  
Bruce McCorkell
Keyword(s):  
Life History ◽  
Life Histories ◽  
Morphological Traits ◽  
Shoot Growth ◽  
Fire Regime ◽  
Habitat Type ◽  
Rock Outcrop ◽  
Experimental Conditions ◽  
North East ◽  
Shoot System

The processes underlying differentiation of seeder and resprouter life histories were explored by studying changes in life history and morphological traits in intraspecific seeder and resprouter populations of the grass Entolasia stricta and shrub Keraudrenia hillii var. hillii from adjoining rock pavement and fringing woodland habitats. Population traits were sampled in the field and studied under controlled conditions in a randomised experimental design with two levels of population/habitat (seeder/rock outcrop and resprouter/woodland) and two levels of fertiliser (low and high). Life history traits reflecting rate of growth, relative allocation of resources to reproductive and vegetative growth and timing of events, as well as a selection of simple morphological traits were recorded. Generalised linear model analysis showed that population had a strong, significant effect on the majority of traits examined, particularly those relating to reproductive output. Many traits were also significantly responsive to nutrient, or induced plasticity, and significant interaction terms were very few. The two species exhibited parallel intraspecific changes in life history between habitats and traits recorded under experimental conditions were similar to those observed in the field. The populations from pavement shrubland produced a more compact shoot system, faster early shoot growth (E. stricta), more numerous flowers and more numerous and lighter seeds. In fringing woodland, both species produced a larger shoot system, slower early shoot growth and fewer and larger seeds. Significant intraspecific differences in population traits and correlation of population with habitat type indicated that the intraspecific seeder-resprouter populations of both species were ecotypes selected by habitat factors, most likely associated with the edaphic environment rather than fire regime variables.

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