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The aim of this study was to determine the changes in the survival, the haemocyte counts, malondialdehyde, superoxide dismutase, catalase, glutathione peroxidase, and phenoloxidase activities of larvae of Hyphantria cunea fed by diets containing various amounts of protein and carbohydrate contents and infected by Bacillus thuringiensis subsp. kurstaki. Second-generation larvae were used in the experiment. Six versions of artificial diets differing in the amounts of proteins and carbohydrates were used. In the infected groups, the number of the surviving larvae decreased compared to the uninfected groups. The malondialdehyde, the superoxide dismutase and the catalase activities increased as the amount of protein contents in the diets increased in both the uninfected and the infected groups. These results indicate that diet plays a significant role in the ability of H. cunea to have an effective immune response against the bacterial infections, with the availability of the protein content being the most important indicator of the functional (physiological) immune response and the carbohydrate contents being crucial to cellular immune function. As a result, it was found that the larvae exposed to the bacterial infection with diet imbalance tried to protect themselves with both cellular and antioxidant enzymes to combat these unfavourable conditions. [ABSTRACT FROM AUTHOR]

Malacosoma neustria is a pest for many plant species. Instead of chemical control, eco-friendly biological control methods should be used to combat this species. The purpose of this study was to evaluate the efficacy of isolates of two entomopathogenic fungi, Metarhizium brunneum (ORP-18) and Beauveria bassiana (GOPT-331), used as both oral and spray application on the 4th instar larvae of M. neustria under laboratory conditions. In addition, it was determined how the infection affected the amounts of malondialdehyde, NADPH oxidase and glutathione of the larvae. Both fungal isolates were placed in separate containers at 2 ml for each concentration (1x105, 1x106, 1x107 and 1x108 conidia/ml) in the oral group and contaminated all over the Elaeagnus rhamnoides leaves and then the contaminated leaves were offered to ten larvae in each container. For the spray group, 2 ml of spray was applied to every ten larvae placed in the containers for each concentration. As a result, it was found that both isolates killed the larvae. The ORP-18 isolate caused higher mortality rates than the GOPT-331 isolate. The spray application was more lethal than the oral application. With increasing conidial concentrations of both isolates, the amounts of malondialdehyde and NADPH oxidases increased, while the glutathione amounts decreased, which indicated the adverse effects of reactive oxygen species (ROS) on larval survival. On the basis of the results, it is recommended to use the ORP-18 isolate for the control of larvae of M. neustria. [ABSTRACT FROM AUTHOR]

In this study, the effects of various secondary metabolites in the economically important plants on the pupal weight, the pupal total protein and the pupal total lipid contents of Hyphantria cunea larvae infected by Bacillus thuringiensis subsp. kurstaki were investigated. In order to find out their effects on the larvae, the phenolic compounds present in Morus alba (mulberry), Malus pumila (apple), Prunus dometica (plum), and Juglans regia (walnut) leaves samples, which are the most preferred by H. cunea and have economic importance, were determined by phytochemical methods. The changes observed in the pupae's weights, total protein and lipid contents were related to the plant leaves' chemical contents. Among the non-infected groups, the mulberry-fed group had the highest both pupal weight and the pupal protein content. The minimum amount of gallotannin, as well as the catechin and rutin contents, was present in the mulberry leaves. The minimum pupal weight and the pupal protein contents were obtained in the larvae fed by the apple leaves with the highest rosmarinic acid and protocatechuic acid. The pupal weights and the pupal total protein contents were decreased by the bacterial infection, while the pupal total lipid contents increased by the bacterial infection. As a result of this study, the effects of both plant secondary metabolites experimentally used and B. thuringiensis infection on the pupal parameters of H. cunea were shown to be statistically significant. [ABSTRACT FROM AUTHOR]

Studies on ecological immunology are crucial in determining how the immune responses of insects against both abiotic and biotic factors are affected. In this study, the effects of phenolic compounds in plants on the immune responses and antioxidant enzyme activities of Hyphantria cunea larvae infected by Bacillus thuringiensis subsp. kurstaki were investigated. For this purpose, phenolic compounds present in mulberry, apple, walnut and plum plants (preferred by H. cunea and having economic importance) were determined. H. cunea culture was obtained from larvae collected in Bafra, Samsun in 2019. It was found that the haemocyte counts of both control and infected larvae fed in the walnut plant containing the highest gallotannin amount were the highest. It was found that catechin and rutin flavonoids caused minimum phenoloxidase activity. It was determined that the highest superoxide dismutase activities were in the plum-fed groups and the lowest catalase activities were in the larvae fed in the walnut groups both in the control and infected groups. As a result, it was determined that immune responses and antioxidant enzyme activities can be changed due to both phenolic compounds present in plants and infection. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the changes in total consumption amounts, survival rates, and phenoloxidase (PO) activities in Malacosoma neustria (L., 1758) (Lepidoptera: Lasiocampidae) larvae infected with Bacillus thuringiensis subsp, kurstaki Berliner. Malacosoma neustria eggs were collected from Bafra District of Samsun, Turkey, in 2018. Malacosoma neustria larvae that hatched from the eggs fed on the host plants, Coryllus maxima Mill., Elaeagnus rhamnoides (L.) A. Nelson, Quercus cerris L. 1753, and Crataegus monogyna Jacq. Except for the control groups, the experiment continued by spraying Bacillus thuringiensis on the plants. The amounts of consumption and survival rates of both the control and infected larvae fed on E. rhamnoides leaves with the highest amounts of protein, phenolic, and gallotannin, were higher than in other groups. In all groups, both the consumption amounts and the survival rates decreased with a bacterial infection. When compared to the control groups, the infected groups had the higher phenoloxidase activities (except C. monogyna). As a result of this study, it was thought that the changes in total consumption amount, survival rates, and PO activities in larvae were related to both bacterial infection and the amounts of protein, phenolic, and gallotannin in the plants. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the changes in cellular and humoral immunity of Uresiphita gilvata larvae fed with diets containing different amounts of protein and carbohydrate and infected with Bacillus thuringiensis subsp. kurstaki. In this context, it has been determined how diet contents and infection affect superoxide dismutase (SOD), manganese superoxide dismutase (MnSOD), catalase (CAT), glutathione peroxidase (GSH-Px), phenoloxidase (PO) enzyme activities and total hemocyte counts of larvae. For this purpose, four different diets were prepared by changing the amounts of protein and carbohydrate. Except for the control groups, other groups were infected with bacteria. In control and infected groups, superoxide dismutase and manganese superoxide dismutase enzymes showed the highest activity in the groups with the highest amount of protein. The catalase enzyme showed inhibition in all infected groups compared to control groups. As the amount of protein in the control groups increased, the phenoloxidase enzyme was found to be activated. It was found that the number of hemocytes decreased with infection (except H). Larvae exposed to infection and diet imbalance try to protect themselves with both cellular and humoral defense to combat these negativities. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effect of tannic acid, some heavy metals (nickel, zinc and copper) and their combinations, and Bacillus thuringiensis subsp. kurstaki infection on the catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase (SOD) enzymes and hemocyte count of Hyphantria cunea larvae. For this purpose, 1 diet was prepared by adding tannic acid to 5% concentration of dry weight in the control diet. Nickel, zinc, and copper solutions were prepared and 3 diets were made and 3 diets were made with tannic acid and heavy metal combinations. All analyzes were determined by ANOVA-Dunnet test. The hemocyte count was the highest in the larvae fed with the control diet. Hemocyte counts of all groups increased with infection compared to control groups. SOD, CAT and GPx activities of the larvae fed with heavy metals and tannic acid diet increased compared to the larvae fed with the control diet. Synergistic and antogonistic effects were observed in some groups where heavy metals and tannic acid were combined. [ABSTRACT FROM AUTHOR]

In this study, the effects of phenolic compounds such as tannic acid and gallic acid, and heavy metals such as iron, zinc, copper, nickel and cobalt on the last larval stage of the first generation of H. cunea were investigated. The larvae were collected from mulberry and hazelnut trees in the district of Çar°amba, Samsun in 2016. 18 foods in total were prepared; two foods by adding 5% concentration of tannic acid and gallic acid to the artificial diet (dry weight), 5 foods by preparing nickel, zinc, copper, cobalt and iron solutions prepared at 8% concentrations, 10 foods by adding 8% concentrations of heavy metal solutions to 5% concentrations of tannic acid and gallic acid separately, and a control diet. Compared to those fed with control food, the consumption amount of the larvae whose diet contained iron, zinc and copper decreased, whereas it increased in the ones fed with nickel and cobalt containing foods. Pupae weight of the larvae fed with tannic acid and metals added(other than nickel) to it has decreased compared to the larvae in control group. While the amount of pupa protein was the lowest in larvae fed with the food in which both gallic acid and zinc used, it was highest in larvae fed with food containing gallic acid. The pupa lipid amount of the larvae fed with foods supplemented with iron, zinc, copper and cobalt were lower than the control group larvae. The longest development time was observed in the larvae in food groups where iron was added to food alone and tannic acid and iron were added together. The results in this study have shown that the addition of secondary compounds and heavy metals together to the artificial food content may increase toxicity of compounds (synergism) or reduce it (antagonism). [ABSTRACT FROM AUTHOR]

In this study the influence of plant protein and secondary compounds on the survival rate of Lymantria dispar L. which was infected with Lymantria dispar nucleopolyhedrovirus (LdNPV), was investigated by using four different plant species, Elaeagnus rhamnoides (L.) A. Nelson, Quercus cerris L. 1753, Corylus maxima Mill. and Crataegus monogyna Jacq. The highest survival rate has been observed on the larvae feeding on the E. rhamnoides (L.) A. Nelson that had the highest protein rate. On the other hand, the highest mortality rate was recorded on the larvae which fed on the C. monogyna Jacq. containing the lowest protein rate. We have also discovered that the survival rate was related to gallotannin amounts. The survival rates of the infected larvae which fed on E. rhammoides (L.) A. Nelson with the highest gallotannin amount were higher than the other diets. Our results showed that the survival rates in the larvae infected with Lymantria dispar nucleopolyhedrovirus were positively related to the proanthocyanidin (condensed tannin) and total phenolic content of foods. [ABSTRACT FROM AUTHOR]