133 research outputs found
Effects of temperature and dietary nitrogen on genetic variation and covariation in gypsy moth larval performance traits
To assess the plastic and genetic components of variation in responses of gypsy moth (Lymantria dispar) 4th instar larvae to temperature and food quality, we applied a split-family four-environment experimental design where full-sibs were reared on two constant temperatures (23Ā°C and 28Ā°C) and two concentrations of dietary nitrogen (1.5 and 3.7% dry weight). A temperature of 28Ā°C and low dietary nitrogen decreased larval weight and prolonged larval developmental time, while viability was not affected. Only a marginally significant interaction between the two environmental factors was found for larval weight. The broad-sense heritability for larval developmental time did not change across environments, and across-environment genetic correlations were close to one. Heritability for larval weight depended on environmental and across-environmental genetic correlations that were not significant. There was no evidence of a trade-off between developmental time and larval weight. The implications of the obtained results for the evolution of phenotypic plasticity in complex environments are discussed.Projekat ministarstva br. 17302
Nutritive stress effects on growth and digestive physiology of Lymantria dispar larvae
The effects of parental and offspring diet on larval growth, food consumption and utilization, and activities of three digestive enzymes (a-amylase trypsin, leucine aminopeptidase) were examined in extremely polyphagous insect, the gypsy moth (Lymantria dispar). In parental generation, gypsy moth larvae were reared on oak (Quercus cerris) leaves as optimal host or beech (Fagus silvatica) leaves which contains flavonoids and alkaloids. In offspring generation, after molting into the 4th instar, they were either switched from oak to beech or remained on oak leaves. Decreased growth and food utilization efficiency, increased assimilation efficiency and activities of a-amylase and trypsin were recorded in larvae switched to beech leaves. Significant parental effects were demonstrated for fourth instar duration, weight of fifth instar larvae and specific activity of leucine aminopeptidase. Physiological, ecological and evolutionary context of the obtained results were stressed in the present paper.Kod gubara (Lymantria dispar), izrazito polifagnog insekta, ispitivan je efekat ishrane u roditeljskoj i potomaÄkoj generaciji na rast larvi konzumaciju i utilizaciju hrane i aktivnost tri digestivna enzima (a-amilaze, tripsina, leucin aminopeptidaze). Larve gubara su u roditeljskoj generaciji gajene na liÅ”Äu hrasta (Quercus cerris) kao optimalnom domaÄinu ili liÅ”Äu bukve (Fagus silvatica) koje sadrži flavonoide i alkaloide. U potomaÄkoj generaciji, posle ulaska u IV stupanj, larve su ili prebaÄene sa hrastovog na bukovo liÅ”Äe ili su nastavile da se hrane hrastovim liÅ”Äem. Kod larvi prebaÄenih na ishranu bukovim liÅ”Äem pokazan je smanjen rast i efikasnost utilizacije hrane, poveÄana efikasnost asimilacije i aktivnost a-amilaze i tripsina. ZnaÄajan parentalni efekat je dobijen za trajanje IV stupnja, težinu larvi u V stupnju i specifiÄnu aktivnost leucin aminopeptidaze. U ovom radu je istaknut fizioloÅ”ki, ekoloÅ”ki i evolucioni kontekst dobijenih rezultata
Genetic variation and correlations of life-history traits in gypsy moths (Lymantria dispar L.) from two populations in Serbia
Periodic fluctuations in density impose different selection pressures on populations of outbreaking Lepidoptera due to changes in their nutritional environment. The maternal effects hypothesis of insect outbreak predicts the transmission of this nutritional "information" to subsequent generations and alterations in offspring life-history traits. To test for these time-delayed effects of the parental generation, we compared life-history traits and their variation and covariation among laboratory-reared gypsy moths hatched from egg masses collected from low- and medium-density populations. Decreased individual performance was recorded in offspring from the medium-density population, indicating reduced egg provisioning under crowding conditions. Genetic variance and covariance were also shown to be sensitive to density of the parental generation. In gypsy moths from the medium-density population, quantitative genetic analysis revealed significantly higher broad-sense heritabilities for development duration traits and demonstrated a trade-off between development duration and body size
Desperate times call for desperate measures: Short-term use of the common ash tree by gypsy moth larvae (Lepidoptera: Erebidae) under density and starvation stress
Gypsy moth, Lymantria dispar L. (Lepidoptera: Erebidae) feeds on a large number of tree species, while ash, Fraxinus spp. (Lamiales: Oleaceae) species are considered resistant and are only sporadically eaten. To assess the conditions under which late instar gypsy moth larvae (GML) can temporarily use non-host common ash (CA) (F. excelsior L.), and to evaluate their ability to recover from ingestion of this toxic food, we determined the relative growth rate, the relative consumption rate and the amount of produced feces in different laboratory feeding trials. Our report is the first to show that under specific circumstances, the resources acquired after short-term consumption of CA leaves can be utilized for larval growth. We varied the intensity of density and starvation stress prior to feeding on CA leaves. We observed that after moderate stress a group of GML was temporarily capable of coping with CA leaves. Although observed growth and consumption were much lower on CA than on the optimal host oak, Quercus cerris L. (Fagales: Fagaceae), CA-oak-switched larvae showed the ability to recover from short-term use of a toxic non-host foliage. This suggests that feeding on CA might enable GML to survive under conditions of food shortage
Nutritive stress effects on growth and digestive physiology of Lymantria dispar larvae
The effects of parental and offspring diet on larval growth, food consumption and utilization, and activities of three digestive enzymes (a-amylase trypsin, leucine aminopeptidase) were examined in extremely polyphagous insect, the gypsy moth (Lymantria dispar). In parental generation, gypsy moth larvae were reared on oak (Quercus cerris) leaves as optimal host or beech (Fagus silvatica) leaves which contains flavonoids and alkaloids. In offspring generation, after molting into the 4th instar, they were either switched from oak to beech or remained on oak leaves. Decreased growth and food utilization efficiency, increased assimilation efficiency and activities of a-amylase and trypsin were recorded in larvae switched to beech leaves. Significant parental effects were demonstrated for fourth instar duration, weight of fifth instar larvae and specific activity of leucine aminopeptidase. Physiological, ecological and evolutionary context of the obtained results were stressed in the present paper.Kod gubara (Lymantria dispar), izrazito polifagnog insekta, ispitivan je efekat ishrane u roditeljskoj i potomaÄkoj generaciji na rast larvi konzumaciju i utilizaciju hrane i aktivnost tri digestivna enzima (a-amilaze, tripsina, leucin aminopeptidaze). Larve gubara su u roditeljskoj generaciji gajene na liÅ”Äu hrasta (Quercus cerris) kao optimalnom domaÄinu ili liÅ”Äu bukve (Fagus silvatica) koje sadrži flavonoide i alkaloide. U potomaÄkoj generaciji, posle ulaska u IV stupanj, larve su ili prebaÄene sa hrastovog na bukovo liÅ”Äe ili su nastavile da se hrane hrastovim liÅ”Äem. Kod larvi prebaÄenih na ishranu bukovim liÅ”Äem pokazan je smanjen rast i efikasnost utilizacije hrane, poveÄana efikasnost asimilacije i aktivnost a-amilaze i tripsina. ZnaÄajan parentalni efekat je dobijen za trajanje IV stupnja, težinu larvi u V stupnju i specifiÄnu aktivnost leucin aminopeptidaze. U ovom radu je istaknut fizioloÅ”ki, ekoloÅ”ki i evolucioni kontekst dobijenih rezultata
Effects of temperature and dietary nitrogen on genetic variation and covariation in gypsy moth larval performance traits
To assess the plastic and genetic components of variation in responses of gypsy moth (Lymantria dispar) 4th instar larvae to temperature and food quality, we applied a split-family four-environment experimental design where full-sibs were reared on two constant temperatures (23Ā°C and 28Ā°C) and two concentrations of dietary nitrogen (1.5 and 3.7% dry weight). A temperature of 28Ā°C and low dietary nitrogen decreased larval weight and prolonged larval developmental time, while viability was not affected. Only a marginally significant interaction between the two environmental factors was found for larval weight. The broad-sense heritability for larval developmental time did not change across environments, and across-environment genetic correlations were close to one. Heritability for larval weight depended on environmental and across-environmental genetic correlations that were not significant. There was no evidence of a trade-off between developmental time and larval weight. The implications of the obtained results for the evolution of phenotypic plasticity in complex environments are discussed.Projekat ministarstva br. 17302
Anaplastic large cell lymphoma
Anaplastic large cell lymphoma is defined by a proliferation of large pleomorphic blasts and a constant expression of the CD30 molecule on all neoplastic cells, and has been clinically subdivided into a primary form and a secondary form. We are presenting a case of 14-year-old boy with reddish-livid papules on the skin of right half of trunk that were confluent in the lower end into solid plaque with diameter 20 x 15 cm, and enlarged lymph nodes in axilla and on neck. Lesioned skin biopsy, biopsy of lymph node and bone marrow showed pleomorphic cells, strongly CD30, and ALK positive. In our patient diagnosis was reached on the basis of morphological and immunohistochemical characteristics
The effects of cadmium on the life history traits of Lymantria dispar L.
Gypsy moth (Lymantria dispar L.) females and males were chronically exposed to three sublethal cadmium concentrations (10, 30 and 50 mg/g dry food mass) in order to assess the effects of cadmium on larval and pupal duration, pupal mass and longevity. On average, the presence of cadmium in food did not affect larval duration while shortened pupal duration and reduced pupal mass and longevity were recorded. The most significant effects were obtained at the highest cadmium concentration. Females and males did not differ in sensitivity of life history traits to cadmium exposure. It is concluded that (1) cadmium exerts a strong adverse impact on the growth and development of gypsy moths, and (2) the significance of the cadmium effects depends on the dose.Projekat ministarstva br. 14303
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