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1.
Females of Tetranychus urticae Koch were reared on leaf discs of apple trees and bush beans grown at different N concentrations (0.6–75 mM NO
inf3
sup-
). N-deficiency increased pre-imaginal development time, preoviposition period, and decreased female weight, fecundity and oviposition rate of the mites. N, water, amino acid, and sugar content of the apple leaves were positively correlated with weight and egg production and negatively correlated with development time and pre-oviposition period. The reverse correlations were found with total phenol content of the leaves and above mite parameters. A reduction of leaf N by 50% was related with a tenfold decline in fecundity on apple leaves. The stress mainly affected the oviposition rate and to a lesser extent the oviposition period. On apple leaves the net reproductive rate (av. no. offspring per , Ro), mean length of a generation (T), and innate capacity for increase (rm) were Ro=40.3, T=17.1, and rm=0.22 for the standard N concentration, and 4.7, 25.0, and 0.06 for strong N-deficiency, respectively.
Zusammenfassung Die polyphage Gemeine Spinnmilbe ist ein wirtschaftlich bedeutender Schädling. Die Rolle einzelner Nährstoffe bei der Milbenvermehrung wurde schon von einigen Autoren mit unterschiedlichen Ergebnissen untersucht. Der Stickstoff scheint aber einer der Hauptfaktoren zu sein.Ueber Gewebekulturen klonierte Apfelbäume sowie aus Samen gezogene Buschbohnen wurden in Nährlösungen mit verschiedenen N-Angeboten kultiviert. Aus solchen Pflanzen wurden Blattscheiben ausgestanzt und mit Weibchen von T. urticae besetzt. Gemessen wurden die tägliche Eiablage bis zum natürlichen Tod, die Entwicklungsdauer und das Weibchengewicht. Mit dem bei N-Mangel abnehmenden N, Aminosäuren- und Zuckergehalt (v.a. Sorbit) im Blatt korrelierend nahmen auch Gewicht, Ablagerate und Fekundität ab, bzw. die Entwicklungsdauer und Praeovipositionsperiode zu. Die umgekehrte Wirkung auf diese Milbenparameter hatte der Gesamtphenolgehalt. Eine Reduktion des N-Gehalts der Blätter auf die Hälfte (1.5% N) bewirkte auf Apfelblättern eine Abnahme von Fekundität und Ovipositionsrate um das zehnfache, bzw. eine Zunahme der Präovipositionsperiode um mehr als das dreifache. Der Stress beeinflusste v.a. die Maxima der Ablageverläufe und weniger die Lebensdauer. Der Wassergehalt war ebenfalls mit der Fekundität positiv korreliert.Auf Bohnenblättern legten die Tiere mehr Eier und erreichten ein höheres Gewicht als auf Apfel, dies bei gleichem N-Gehalt beider Pflanzen. Es wirken somit noch andere Faktoren auf die Reproduktion der Spinnmilben.Die Populationsparameter wurden ebenfalls sehr stark beeinflusst. Auf Apfelblättern ergab sich bei der Kontrolle eine Nettoreproduktionsrate Ro von 40.3 und bei starker N-Defizienz 4.7. Die mittlere Generationsdauer T sowie die spezifische natürliche Wachstumsrate rm betrugen für die Kontrolle 17.1 Tage, bzw. 0.22 und für starken N-Mangel 25.0 Tage, bzw. 0.06.Die Ergebnisse zeigen, dass sich bereits kleinere Unterschiede im Stickstoffgehalt und damit zusammenhängend im Zucker- und Phenolgehalt stark auf die Populationsdynamik der Gemeinen Spinnmilbe auswirken können.相似文献
2.
The conversion of aphid prey tissue (Acyrthosiphon pisum Harris) into predator biomass (immature life stages ofPropylaea 14-punctata L. andCoccinella 7-punctata L.) is calculated by plotting weight gain against assimilation (i.e. consumption minus egestion). This concept is added to
the metabolic pool model byGutierrez
et al. (1981) that enables the simulation of growth and development of a predator on a physiological basis. Physiological time is
expressed in daydegrees above lower development thresholds for both species. Visual examination of observed and calculated
values showed that the model satisfactorily describes the growth patterns of the above predators.
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3.
4.
The rate of cigarette smoking is greater among persons with mental health and/or substance abuse problems. There are few population-based datasets with which to study tobacco mortality in these vulnerable groups. The Oregon Health Authority identified persons who received publicly-funded mental health or substance abuse services from January 1996 through December 2005. These cases were then matched to Oregon Vital Statistics records for all deaths (N= 148,761) in the period 1999-2005. The rate of tobacco-related death rates was higher among persons with substance abuse problems only (53.6%) and those with both substance abuse and mental health problems (46.8%), as compared to the general population (30.7%). The rate of tobacco-related deaths among persons with mental health problems (30%) was similar to that in the general population. Persons receiving substance abuse treatment alone, or receiving both substance abuse and mental health treatment, were more likely to die and more likely to die prematurely of tobacco-related causes as compared to the general population. Persons receiving mental health services alone were not more likely to die of tobacco-related causes, but tobacco-related deaths occurred earlier in this population. 相似文献
5.
V. Delucchi 《Journal of Applied Entomology》2001,125(9-10):493-500
The beetle Dicladispa gestroi is known only from Madagascar, where it is considered to be a pest of rice. Research were carried out from 1885 to 1994 in the Alaotra lake region, the main rice-producing area of the country, characterized by a warm rainy season from October to April and a cool dry season from April to October. The adult beetles invade the rice nurseries and the first direct-seeded fields at the beginning of the rainy season; they have a gregarious behaviour and their feeding activity, together with the mines bored by the larvae, determines a change of colour from green to pale yellow in the damage areas, which resemble outbreak areas of rice leafhoppers. Oviposition takes place only on young rice plants in the tillering stage. Females emerging after the end of February enter a reproductive diapause and leave the rice fields to 'hibernate'. Temperature summations for the egg, larval, and pupal development, as well as for the preoviposition period have been calculated. There is no yield loss up to a larval density of 0.6 per leaf and this economic injury level is seldom exceeded in the Alaotra lake region. Life tables carried out under field conditions show that chalcid parasitoids are the main mortality factor and are responsible for the collapse of entire outbreak areas. Since the discovery of the rice yellow mottle virus in 1989 in the Alaotra lake region and the disease transmission by chrysomelids, the pest status of D. gestroi has changed and control measures have to be applied. However, to avoid interference with the action of the parasitoids, chemical applications should be limited to rice nurseries. 相似文献
6.
Muraski JA Rota M Misao Y Fransioli J Cottage C Gude N Esposito G Delucchi F Arcarese M Alvarez R Siddiqi S Emmanuel GN Wu W Fischer K Martindale JJ Glembotski CC Leri A Kajstura J Magnuson N Berns A Beretta RM Houser SR Schaefer EM Anversa P Sussman MA 《Nature medicine》2007,13(12):1467-1475
The serine-threonine kinases Pim-1 and Akt regulate cellular proliferation and survival. Although Akt is known to be a crucial signaling protein in the myocardium, the role of Pim-1 has been overlooked. Pim-1 expression in the myocardium of mice decreased during postnatal development, re-emerged after acute pathological injury in mice and was increased in failing hearts of both mice and humans. Cardioprotective stimuli associated with Akt activation induced Pim-1 expression, but compensatory increases in Akt abundance and phosphorylation after pathological injury by infarction or pressure overload did not protect the myocardium in Pim-1-deficient mice. Transgenic expression of Pim-1 in the myocardium protected mice from infarction injury, and Pim-1 expression inhibited cardiomyocyte apoptosis with concomitant increases in Bcl-2 and Bcl-X(L) protein levels, as well as in Bad phosphorylation levels. Relative to nontransgenic controls, calcium dynamics were significantly enhanced in Pim-1-overexpressing transgenic hearts, associated with increased expression of SERCA2a, and were depressed in Pim-1-deficient hearts. Collectively, these data suggest that Pim-1 is a crucial facet of cardioprotection downstream of Akt. 相似文献
7.
F Delucchi R Berni C Frati S Cavalli G Graiani R Sala C Chaponnier G Gabbiani L Calani D Del Rio L Bocchi C Lagrasta F Quaini D Stilli 《PloS one》2012,7(6):e39836
Emerging evidence suggests that both adult cardiac cell and the cardiac stem/progenitor cell (CSPC) compartments are involved in the patho-physiology of diabetic cardiomyopathy (DCM). We evaluated whether early administration of Resveratrol, a natural antioxidant polyphenolic compound, in addition to improving cardiomyocyte function, exerts a protective role on (i) the progenitor cell pool, and (ii) the myocardial environment and its impact on CSPCs, positively interfering with the onset of DCM phenotype. Adult Wistar rats (n?=?128) with streptozotocin-induced type-1 diabetes were either untreated (D group; n?=?54) or subjected to administration of trans-Resveratrol (i.p. injection: 2.5 mg/Kg/day; DR group; n?=?64). Twenty-five rats constituted the control group (C). After 1, 3 or 8 weeks of hyperglycemia, we evaluated cardiac hemodynamic performance, and cardiomyocyte contractile properties and intracellular calcium dynamics. Myocardial remodeling and tissue inflammation were also assessed by morphometry, immunohistochemistry and immunoblotting. Eventually, the impact of the diabetic "milieu" on CSPC turnover was analyzed in co-cultures of healthy CSPCs and cardiomyocytes isolated from D and DR diabetic hearts. In untreated animals, cardiac function was maintained during the first 3 weeks of hyperglycemia, although a definite ventricular remodeling was already present, mainly characterized by a marked loss of CSPCs and adult cardiac cells. Relevant signs of ventricular dysfunction appeared after 8 weeks of diabetes, and included: 1) a significant reduction in ±dP/dt in comparison with C group, 2) a prolongation of isovolumic contraction/relaxation times, 3) an impaired contraction of isolated cardiomyocytes associated with altered intracellular calcium dynamics. Resveratrol administration reduced atrial CSPC loss, succeeded in preserving the functional abilities of CSPCs and mature cardiac cells, improved cardiac environment by reducing inflammatory state and decreased unfavorable ventricular remodeling of the diabetic heart, leading to a marked recovery of ventricular function. These findings indicate that RSV can constitute an adjuvant therapeutic option in DCM prevention. 相似文献
8.
Vittorio Delucchi 《BioControl》1956,1(1):65-75
Summary In the present paper the Author has described three new genera ofPteromalidae, two new species of the genusEnaysma
Del. and one of the genusEpilampsis
Del. (Euloph. Entedontinae). The first Pteromalid genus,Stenoselma, is closely related to the well knownAnisopteromalus
Ruschka; the second new genus,Apelioma, has been proposed forDinotiscus (Dinotus) pteromalinus
Thomson; the third,Aggelma, has been described for the new speciesabdominalis, collected in Central Europe onPinus montana. The other new species ofEntedontinae has been bred from leaf-miners (Lepidoptera).
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9.
V. Delucchi 《BioControl》1961,6(2):97-101
Summary The author examines in his report some aspects of the relations existing between the ecologists of the C.I.L.B. working teams
and the taxonomists which collaborate with the identification centre, and between these taxonomists and the identification
centre itself. The collaboration between taxonomists and ecologists must certainly be encouraged by the C.I.L.B., especially
with regard to those biological control projects such as the Olive fly and the San Jose Scale, where behavioural caracters
of the parasitic species may be determinant for their identification. Emphasis is given to the importance of the behavioural
caracters in taxonomy and examples of this are reported. The collaboration between taxonomists and the identification centre
of the C.I.L.B. would be favoured through the following: 1. The establishment of a card file at the C.I.L.B. head-quarters
on the entomophagous insect species and their known hosts for a future publication of a synoptic catalog for the palaearctic
region; 2. The institution of fellowships for taxonomists to study Museum collections; 3. The establishment of a homotype
collection at the C.I.L.B. headquarters, which will constitute, with the file card system, a solid base for the future development
of taxonomic work; 4. The reservation of a day for discussions about nomenclature questions at every C.I.L.B. meeting of taxonomists.
The author recommends to address reprints concerning the taxonomy and systematic of entomophagous species to the C.I.L.B.
headquaters (Entomologisches Institut der E.T.H., Universit?tstrasse 2, Zürich 6, Switzerland) for the establishment of an
extensive reference collection to be used for publication of the bibliography on this subject.
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10.
Partial migration in roe deer: migratory and resident tactics are end points of a behavioural gradient determined by ecological factors 总被引:1,自引:0,他引:1
Francesca Cagnacci Stefano Focardi Marco Heurich Anja Stache A. J. Mark Hewison Nicolas Morellet Petter Kjellander John D. C. Linnell Atle Mysterud Markus Neteler Luca Delucchi Federico Ossi Ferdinando Urbano 《Oikos》2011,120(12):1790-1802
Ungulate populations exhibiting partial migration present a unique opportunity to explore the causes of the general phenomenon of migration. The European roe deer Capreolus capreolus is particularly suited for such studies due to a wide distribution range and a high level of ecological plasticity. In this study we undertook a comparative analysis of roe deer GPS location data from a representative set of European ecosystems available within the EURODEER collaborative project. We aimed at evaluating the ecological factors affecting migration tactic (i.e. occurrence) and pattern (i.e. timing, residence time, number of migratory trips). Migration occurrence varied between and within populations and depended on winter severity and topographic variability. Spring migrations were highly synchronous, while the timing of autumn migrations varied widely between regions, individuals and sexes. Overall, roe deer were faithful to their summer ranges, especially males. In the absence of extreme and predictable winter conditions, roe deer seemed to migrate opportunistically, in response to a tradeoff between the costs of residence in spatially separated ranges and the costs of migratory movements. Animals performed numerous trips between winter and summer ranges which depended on factors influencing the costs of movement such as between‐range distance, slope and habitat openness. Our results support the idea that migration encompasses a behavioural continuum, with one‐trip migration and residence as its end points, while commuting and multi‐trip migration with short residence times in seasonal ranges are intermediate tactics. We believe that a full understanding of the variation in tactics of temporal separation in habitat use will provide important insights on migration and the factors that influence its prevalence. 相似文献