Longevity, host preference, length of life stages and the number of offspring of Habrobracon hebetor were evaluated on the host larvae of Ephestia kuehniella treated with lethal and sub-lethal doses of Bacillus thuringiensis Experiments were conducted in a completely randomized design under laboratory condition. The number of eggs decreased from 3.9 in control to 1.4 and 2.7 in lethal and sub-lethal doses, respectively. By reducing the number of parasitoid offspring from 3.7 in control to 0.6 and 1.2 in lethal and sub-lethal doses, also the adult parasitoid longevity decreased from 15.6 days in control to 12.3 and 13.7 days in lethal and sub-lethal doses, respectively. In the lethal dose of Bt treatment, duration of embryonic and larval stages of the wasp showed a significant increase compared to control, but pupal stage duration decreased in both lethal and sub-lethal doses of Bt treatment. Generally, by reducing the usage dose of Bt and avoiding its application during the critical stages of parasitoid life, the efficiency of their use in integrated pest management can be improved.

Whether exposure to common electromagnetic fields affects human health adversely has been a controversial issue. The main goal of this study was to assess the role of 900 MHz microwave radiations with different specific absorption rates (SARs), emitted from some widely used cell phones, on the induction of adaptive response in male Balb/c mice after receiving a lethal dose of gamma radiation. This study was conducted on 120 male Balb/c mice. The animals were divided into groups of 20 mice each (6 groups). Group one (the control group) received neither microwave radiation nor the lethal dose of gamma radiation. Group two was exposed only to the lethal dose of 8.8 Gy. The mice in group three were first exposed to low SAR 900 MHz microwave radiations emitted from a cell phone for six hours (3 hours in the morning and 3 hours in the afternoon) for 5 days and then were exposed to a lethal dose of 8.8 Gy on day six. The mice in group 4 were treated as those in group 3 but with a moderate SAR and the mice in group 5 were also treated as those in groups 3 and 4 but with a high SAR. The mice in group six were exposed only to high SAR 900 MHz microwaves. All groups were monitored for 12 days and their daily mortality rates were recorded. The results showed that there was a statistically significant difference between group two (the animals exposed only to lethal dose of gamma radiation) and the groups with a pre-exposure to microwave radiations before receiving the lethal dose. To the best of our knowledge, this is the first study that investigates the role of SAR on the induction of microwave-induced survival adaptive response. It can be concluded that 900 MHz microwaves emitted from cell phones, regardless of their SAR can induce adaptive responses which make the animals more resistant to subsequent lethal doses of ionizing radiation. These findings also confirm our preliminary findings obtained in a previous study.

In the present study, we investigated the effect of ischemic preconditioning (IPC) on c-myb immunoreactivity as well as neuronal damage/death after a subsequent lethal transient ischemia in gerbils.
IPC was subjected to a 2 min sublethal ischemia and a lethal transient ischemia was given 5 min transient ischemia. The animals in all of the groups were given recovery times of 1 day, 2 days and 5 days and we examined change in c-myb immunoreactivity as well as neuronal damage/death in the hippocampus induced by a lethal transient ischemia.
A lethal transient ischemia induced a significant loss of cells in the stratum pyramidale (SP) of the hippocampal CA1 region at 5 days post-ischemia, and this insult showed that c-myb immunoreactivity in cells of the SP of the CA1 region was significantly decreased at 2 days post-ischemia and disappeared at 5 days post-ischemia. However, IPC effectively prevented the neuronal loss in the SP and showed that c-myb immunoreactivity was constitutively maintained in the SP after a lethal transient ischemia.
Our results show that a lethal transient ischemia significantly decreased c-myb immunoreactivity in the SP of the CA1 region and that IPC well preserved c-myb immunoreactivity in the SP of the CA1 region. We suggest that the maintenance of c-myb might be related with IPC-mediated neuroprotection after a lethal ischemic insult.

Adaptive response is one of the important concepts in radiobiology. The present report aimed to transfer the radio-adaptation via serum.
In total, 50 male adult Wistar rats were randomly divided into 6 groups, including control, serum control, low-dose (100cGy), low-dose/lethal, serum/lethal, and lethal (8Gy). Exposure was carried out by a linear accelerator (Elekta Synergy® Platform) with a 40×40cm field size. The animals were monitored in terms of the endpoints of the survival rate, and at the first stage, the rats were exposed to the low doses of radiation. Subsequently, the serum was injected intraperitoneally under sterile conditions 6 h after low-dose exposure. The Kaplan Meier Survival Curve was used to evaluate the survival rate (P<0.05).
There was a significant difference among different groups regarding the survival rates. Moreover, a statistically significant difference was observed between low-dose/lethal and low-dose/serum, low-dose/lethal and lethal, and low-dose/serum and lethal (P=0.001). Similarly, there was a statistically significant difference between the control and experimental groups regarding the survival rates (P=0.001).
To the best of our knowledge, this method can lead to immunological responses or unknown mechanisms that result in the increased survival adaptive response to subsequent high-dose radiation.

Population growth and the high food demand have led to more efforts to increase agricultural production. With making chemical pesticides, farmers were encouraged to use much chemicals, but their destructive effects on the environment, human and other organisms have been later revealed. Parasitoids are important natural enemies of crop pests. Most of them belong to order hymenoptera and superfamily Ichneumonoidea. The Braconidae is a family of parasitoid wasps and one of the richest families of insects. Nowadays, parasitoid wasp, Habrobracon hebetor Say has been widely used against lepidopteran larvae. Habrobracon hebetor is a well-known gregarious, idiobiont, ectoparasitoid of the larvae of a wide range of economically important moths infesting stored grains, nuts, and fruits as well as field crops worldwide. Due to overuse of chemical pesticides for larvae controlling, determining the side effects of insecticides on the biocontrol agents such as parasitoids is required.

In the present study, we investigated the side effects of three insecticides on H. hebetor by direct (contact) and indirect (poisonous-host) methods. After rearing this parasitoid on the laboratory host, Ephestia kuhniella Zeller (Lep.; Pyralidae), the lethal and sub-lethal concentrations of insecticides were evaluated. Bioassay experiments were carried out under laboratory condition (25±2°C, 60±5% RH, 16L: 8D photoperiods) in five replicates and each replication included 30 parasitoids in contact method and 15 flour moth larvae in poisonous-host method. The lethal concentrations of these insecticides in contact method on the parasitoid were determined to be 1.38, 0.037 and 6.621 ml/L and on flour moth larvae were 0.490, 2.155 and 0.138 ml/L, respectively. For contact method, different concentrations of insecticides were applied on all inner sides of transparent plastic cup (4.5×8 cm) and air-dried. 15 pairs of 24-hours old parasitoids were introduced inside each cup. After 24 hours, one pair of alive parasitoids was introduced into cup with four last instar host larvae to oviposit. The host larvae were replaced daily. The parasitoid characteristics such as longevity and survival rate of different stages, TPOP and Ovi-day, the number of deposited eggs and sex ratio were then recorded. As to poisonous-host method, whole wheat flour (10 g) was mixed with 3.5 ml of each tested concentration of insecticides per each experimental set. After 72 hours, alive larvae were transferred in a plastic cup with one pair of H. hebetor wasp for 24 hours. Then, each larva was transferred separately in a petri dish with untreated flour. Different growth factors of parasitoids such as longevity and survival rate, TPOP and Ovi-day, the number of deposited eggs and sex ratio were recorded. Estimated LC30 and LC50 were considered as sub-lethal and lethal concentrations in all experiments, respectively.

In contact method, the highest survival rate of pre-adult stages and adult female were observed in Sirinol treatment at lethal concentration, after control. In poisonous-host method, the highest survival ratio of the pre-adult stages belongs to Sirinol and in adult female the highest survival ratio was observed in lethal concentration of Sirinol. The lethal concentration of Proteus reduced pre-adult longevity of the parasitoid significantly, followed by lethal and sub-lethal concentration of Sirinol. Lethal and sub-lethal concentrations of Proteus also exhibited a significant reduction of total longevity. In poisonous-host method, all concentrations of all insecticides generally induced highly significant differences for ovi-day compared with that of control (17.91 days), as the shortest value was recorded for sub-lethal dose of Abamection (7.46 days) and the longest period was found for sub-lethal dose of Sirinol (13.2 days). In poisonous-host method, the longest TPOP was observed in sub-lethal concentration of Sirinol (16.02 days), followed by sub-lethal concentration of Abamection (14.63 days), and the shortest period was recorded in sub-lethal concentration of Proteus (12.3 days), after control (12.19 days). On the other hand, in contact method, the longest ovi-day and TPOP were observed in sub-lethal concentration of Sirinol (18.19 days) and lethal concentration of Abamection (13.26 days), respectively. The shortest adult female longevity was observed in lethal concentration of Proteus (27.55 days) in contact method and lethal concentration of Sirinol (22.85 days) in poisonous-host method. In all treatments, the number of deposited eggs was significantly reduced compared with control. The largest reduction in egg deposition was recorded for sub-lethal concentration of Proteus (71.05 eggs) in contact method and sub- lethal concentration of Abamection (36.14 eggs) in poisonous-host method, compared with control (227.47 eggs). It seems that Sirinol is suited to be used as a component of IPM alongside with H. hebetor.

In present study, it was determinated LC50 96-h and toxicity degree of diazinon in Huso huso, then were evaluated effects of sub-lethal concentrations on tow general enzymatic indices including Alanine and Aspartate aminotransferase of plasma and one specific enzymatic index including tissue AChE enzyme. The median lethal concentration, lowest observed effect concentration and maximum allowable toxicant concentration was measured 5.47, 4.28 and 0.54 mg.L-1, respectively. Also, diazinon according by amount of LC50 was classified in “moderate toxicity degree” for this sturgeon. The test results showed that with increasing sub-lethal concentrations of diazinon in water, AST and ALT enzyme activity in experimental fish were increased, Thus, a direct relationship seen between the concentration of diazinon with the public indices. However, increased concentrations of diazinon, causing a decrease in cholinesterase activity in both brain and muscle tissues. In other words, inhibition of AChE is directly related to the concentration of pesticide.The diazinon pesticide concentrations for non-target specieses which were ineffective and allowable according to the lethal test can lead to their enzymatic indicies of serum and AChE responses.

In the recent years, water pollution by contaminations are increasing rapidly, the problems of aquatic pollution with heavy metals which is one of the important pollutions indicate that necessary to assess in fish as an important source of human food. The aim of this study was investigated the sub-lethal effects of zinc chloride on hepatic enzymes activity in grey mullet (Mugil Cephalus). In this study after determining the LC50, Two sub-lethal treatments of zinc chloride includes (1.73 and 3.46 mg/L) was considered that any treatment has three replications. Fish were exposed to different doses of sub-lethal for 1, 7, 14 and 21 days and the end of each period samples of liver tissue was taken. The results showed that with increasing concentration of sub-lethal levels of aspartate aminotransferase (AST), alkaline phosphatase (ALP) and alanine aminotransferase (ALT) significantly increased (P≤0.05). Also with the prolonged exposure amount of enzymes AST, AST and ALT were increased significantly (P≤0.05). Results of this research showed those hepatic enzymes as stress indicator can be important factors to the investigation of eco-toxicological changes.

For successful implementation of integrated pest management (IPM) programs, having knowledge on lethal and low-lethal effects of pesticides on natural enemies is necessary. The present study evaluated the low-lethal effect of thiamethoxam on life table parameters of the subsequent generation of the predatory mite, Neoseiulus californicus McGregor (Acari: Phytoseiidae) fed on Tetranychus urticae Koch under laboratory conditions. The low-lethal concentrations LC5, LC10 and LC20 were determined based on a dose-effect assay. The raw data were analyzed based on age-stage two sex life table analysis. Exposure to the low-lethal concentrations of thiamethoxam had no significant effects on developmental time of offspring of treated mites. Compared with control treatment, the oviposition period of treated mites with LC5, LC10 and LC20 decreased significantly. The highest and lowest values of total fecundity were obtained at control (35.3 eggs/female/day) and LC20 (23.6 eggs /female/day), respectively. The net reproductive rate (R0) decreased with increasing dose from LC5 (22.6 offspring) to LC20 (15.0 offspring). The intrinsic rate of increase (r) and finite rate of increase (λ), were not affected by increasing concentrations. The mean generation time (T) decreased significantly at upper dose (LC20 = 13.2 d), compared with control (14.7 d). In consequence, the low-lethal concentration influences of thiamethoxam in combination with N. californicus in order to design management programs of T. urticae are discussed.

The use of pesticides has always been associated with environmental concerns. Vista is a new and widely used pesticide in rice fields for blast disease. The present study investigated the lethal range and median lethal concentration of Vista fungicide in Ctenopharyngodon idella, for the first time. In this study, to determine the lethal range fish were first exposed to the concentrations of 0,10, 25, 50, 100, 250 and 500 mg per liter of Vista, and fish mortality were recorded in each group for 24, 48, 72 and 96 hours. Then, in order to determine median lethal concentration, fishes in 5 groups received concentrations of 0, 30, 35, 40 and 45 mg per liter Vista with three replication, and the number of fish mortality was recorded at 24, 48, 72 and 96 hours. The results were evaluated by probit statistical analysis. In this study, the median lethal concentration of Vista were 60.5, 40.1, 34.58 and 31.28 mg per liter at 24, 48, 72 and 96 hours, respectively. The Maximum Allowable Toxicant Concentration of Vista fungicide was 3.128 mg per liter, and its Lowest Observed Effect Concentration was estimated to be 28.42 mg per liter. The results of this study showed that the lethal concentration of Vista fungicide decreased with increasing test time, so that as the test time increased, a lower concentration of Vista fungicide caused fish mortality.

The purpose of this study was to determine the lethal concentration (LC50-96 h) of malachite green on rainbow trout and also the histology effects of this substance on the liver, gills and kidney. With increasing concentrations of malachite green, rainbow trout mortality increased during the period of 24 to 96 hours. Twenty four hour lethal concentration (LC50-24 h) of malachite green on O. mykiss is 32.28 mg L-1. Forty eight hour lethal concentration (LC50-48 h) of malachite green is 16.32 mg L-1, and 72-hour lethal concentration (LC50-72 h) of malachite green is 2.52 mg L-1. All lethal concentrations at 72 hours showed a clear reduction compared to 24 and 48 hours. The median lethal concentration of malachite green (LC50-96 h) of rainbow trout was 0.83 mg L-1 during four consecutive days (96 hours). On the other hand, malachite green showed destructive effects on liver, gills and kidney tissue of rainbow trout, and these changes were more intense with increasing concentration of malachite green. Therefore, due to the grading of toxicity is determined by the amount of LC50-96 h and also observing tissue effects exposed to this substance, the malachite green is considered highly toxic to rainbow trout. For this reason, there are always concerns about the possibility of its transmission to consumers or humans; therefore, regarding to this matter that using this substance in the fish farms has been prohibited by Iran Veterinary Organization, it is necessary to remove malachite green from the list of drugs used in fish breeding and provide the other safe drugs.