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

Sensitivity of gypsy moth neurosecretory neurons to acute thermal stress

In gypsy moth caterpillars exposed to a temperature of 35°C (for 1, 12 and 24 h and caterpillars that were exposed to elevated temperature for 12 h and were allowed to recover for 12 h at 23°C), changes in the brain protein profiles and morphometric characteristics of A1’ medial and L2 lateral protocerebral neurosecretory neurons were analyzed. In all groups, protein bands with a molecular mass corresponding to that of members of heat-shock protein families were detected, indicating that acute exposure to this temperature likely induced the synthesis of HSP. Increased morphometric parameters of A1’ neurons and the large amount of neurosecretory material in the neuron body implicate that the temperature of 35°C is not in the temperature range that exerts stimulatory effects on growth and survival. Changes in the morphometric characteristics of L2 neurosecretory neurons from the lateral part of the protocerebrum, and retention of neurosecretory material in their cytoplasm indicate a low level of secretion

Temperature and magnetic field effects on the activity of protocerebral neurosecretory neurons and corpora allata in Cerambyx cerdo L. larvae

The effects of constant temperature and an extremely low-frequency magnetic field (ELFMF, 50 Hz and average induction of 20 mT) on the activity of medial protocerebral neurosecretory neurons (A1 and A2) and corpora allata were investigated in Cerambyx cerdo L. larvae after 30 days of exposure. Both constant temperature of 23°C and the ELFMF led to decrease in activity of A1 and A2 neurosecretory neurons and increase in activity of corpora allata compared to the control group (larvae from natural conditions). The changes are more pronounced in A2 than A1 neurons.Ispitivan je uticaj konstantne temperature i ekstremno niskofrekventnog magnetnog polja (ELFMF, 50 Hz i prosečna indukcija 20mT) na aktivnost medijanih protocerebralnih neurosekretnih neurona (A1 i A2) i corpora allata kod larvi Cerambyx cerdo posle 30 dana izlaganja i konstantna temperatura od 23°C i ELFMF dovode do smanjenja aktivnosti A1 i A2 neurosekretnih neurona i povećanja aktivnosti corpora allata u poređenju sa kontrolnom grupom (larve iz prirodnih uslova). Promene su više izražene kod A2 nego kod A1neurona.nul

Biogenic amines in protocerebral A2 neurosecretory neurons of Lymantria dispar L. (Lepidoptera:Lymantriidae): Response to trophic stress

The number, morphometric parameters and amount of aminergic neurosecretory product of protocerebral A2 neurosecretory neurons were investigated in the fifth instar of Lymantria dispar caterpillars, following a suitable or unsuitable trophic regime. Caterpillars originated from two populations (Quercus rubra or Robinia pseudoacacia forest) and were differently adapted to trophic stress, i.e. feeding on locust tree leaves - unsuitable host plant. The number of neurosecretory neurons was higher in the caterpillars originated from Robinia population than in Quercus population, regardless of feeding. A2 neurosecretory neurons, nuclei and their nucleoli were larger in caterpillars fed with unsuitable leaves in both populations. There was more aminergic product in the A2 neurosecretory neurons of the caterpillars fed with unsuitable leaves independently of population origin

The influence of increased rearing density on medial protocerebral neurosecretory neurons of Lymantria dispar L. caterpillars

Morphometric changes of A1, A1' and A2 protocerebral dorsomedial neurosecretory neurons, total brain protein content and brain protein profiles were analyzed in 4th instar Lymantria dispar larvae under elevated rearing density, i.e. under intense stress when 5 larvae were kept in a petri dish (V = 80 ml), less intense stress when 5 larvae were kept in a plastic cup (V = 300 ml). In the control samples the larvae were reared in isolated conditions. Protein pattern changes in the brain were observed. Proteins with the following molecular masses: 30, 14, 10 and 3.4-2.5 kD were detected in the experimental groups. The size and cytological characteristics of protocerebral dorsomedial neurosecretory neurons were changed under elevated rearing density.U ovom radu je ispitivan uticaj povećane gustine gajenja na gusenice gubara Lymantria dispar L. Morfometrijske promene A1, A1' i A2 dorzomedijalnih neurosekretnih neurona protocerebruma, ukupna količina proteina u homogenatima mozga i proteinski profili mozga gusenica gubara 4. larvenog stupnja su ispitivani pod sledećim eksperimentalnim uslovima: intenzivan stres - 5 larvi je gajeno u petri šolji (V = 80 ml), manje intenzivan stres - 5 larvi je gajeno u plastičnim čašama (V = 300 ml) i kontrola - larve su gajene pojedinačno, u izolovanim uslovima. U proteinskim profilima promene su uočene u sledećim regionima molekulskih masa: 30, 14, 10, 3.4-2.5 kD. Veličina i citološke osobine protocerebralnih dorzomedijalnih neurosekretnih neurona se menjaju pod delovanjem povećane gustine gajenja.Projekat ministarstva br. 14303

The response of dorsomedial A1' and dorsolateral L2' neurosecretory neurons of Lymantria dispar L. caterpillars to the acute effects of magnetic fields

The morphometric changes (size of neurons and their nuclei) of protocerebral dorsomedial A1' and dorsolateral L2' neurosecretory neurons were analyzed in Lymantria dispar larvae after exposure to strong static (SMF, 235 mT) and extremely low frequency magnetic fields (ELF MF, 2 mT). Increase in the size of A1' neurons and their nuclei were observed after acute exposure to SMF. Decrease in the size of these neurons and their nuclei was observed after exposure to ELF MF. The size of L2' neurons and their nuclei tend to decrease after exposure to SMF and ELF MF. The quantification of protein bands within the Mr range corresponding to the large form of the prothoracicotropic neurohormone indicates that the amount of protein decreased after exposure to both types of magnetic fields.Projekat ministarstva br. 17302

Sensitivity of gypsy moth neurosecretory neurons to acute thermal stress

In gypsy moth caterpillars exposed to a temperature of 35°C (for 1, 12 and 24 h and caterpillars that were exposed to elevated temperature for 12 h and were allowed to recover for 12 h at 23°C), changes in the brain protein profiles and morphometric characteristics of A1' medial and L2 lateral protocerebral neurosecretory neurons were analyzed. In all groups, protein bands with a molecular mass corresponding to that of members of heat-shock protein families were detected, indicating that acute exposure to this temperature likely induced the synthesis of HSP. Increased morphometric parameters of A1' neurons and the large amount of neurosecretory material in the neuron body implicate that the temperature of 35°C is not in the temperature range that exerts stimulatory effects on growth and survival. Changes in the morphometric characteristics of L2 neurosecretory neurons from the lateral part of the protocerebrum, and retention of neurosecretory material in their cytoplasm indicate a low level of secretion.Projekat ministarstva br. 17302

Biogenic amines in protocerebral A2 neurosecretory neurons of Lymantria dispar L. (Lepidoptera:Lymantriidae): Response to trophic stress

The number, morphometric parameters and amount of aminergic neurosecretory product of protocerebral A2 neurosecretory neurons were investigated in the fifth instar of Lymantria dispar caterpillars, following a suitable or unsuitable trophic regime. Caterpillars originated from two populations (Quercus rubra or Robinia pseudoacacia forest) and were differently adapted to trophic stress, i.e. feeding on locust tree leaves - unsuitable host plant. The number of neurosecretory neurons was higher in the caterpillars originated from Robinia population than in Quercus population, regardless of feeding. A2 neurosecretory neurons, nuclei and their nucleoli were larger in caterpillars fed with unsuitable leaves in both populations. There was more aminergic product in the A2 neurosecretory neurons of the caterpillars fed with unsuitable leaves independently of population origin.Projekat ministarstva br. 17302

Morphometric changes of corpora allata in Morimus funereus müls. (Cerambycidae) larvae during thermal stress

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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