Cellular and biochemical effects induced by atrazine on blood of male Japanese quail (Coturnix japonica)

Atrazine a potent endocrine disruptor herbicide is broadly used to control rapidly growing unwanted weeds in various cereals crops which induce adverse effects both in mammalian and avian species. In present study 96 mature male Japanese quail (Coturnix japonica) were procured and randomly kept in eight groups (A to H) each having 12 birds. Atrazine was administered orally at 0, 10, 25, 50, 100, 250 and 500 mg/kg body weight to all experimental groups. The mitomycin C at 2 mg/kg body weight was given to the birds of group B which served as a positive control. From each group 4 birds were randomly selected and harvested at day 15, 30 and 45. A significant (P < 0.05) decrease in serum total protein, serum albumin and serum testosterone values were recorded at day 45 in all treated groups. A significant increase in serum ALT and AST concentration was also recorded. Moreover, morphological alterations in nucleus of erythrocytes were also observed including blebbed nuclei, notched nuclei, lobed nuclei, vacuolated cells, binucleated cell, and cell with pear shaped and micronucleus. Overall, our results show that atrazine at higher doses induces significant serum biochemical alterations and changes in nucleus of erythrocytes.     

Effects of sodium fluoride on hepatic toxicity in adult mice and their suckling pups

In this investigation, we have evaluated the effect of sodium fluoride (NaF) on hepatic function in pregnant and lactating mice and their suckling pups. Experiments were carried out on female Wistar mice given 500 ppm sodium fluoride (226 ppm fluoride ion) in their drinking water from the 15th day of pregnancy until day 14 after delivery. All mice were sacrificed on day 14 after parturition. Our results showed a significant decrease in serum levels of total protein and albumin, a marked hypoglycaemia and a significant decline in serum cholesterol and triglyceride levels in fluoride-treated mice and their pups. Whereas globulin and biluribin levels in serum were not significantly changed by NaF treatment. On the other hand, serum transaminase activities (aspartate transaminase; alanine transaminase), which well known as markers of liver function, were elevated indicating hepatic cells’ damage after treatment with fluoride. Lipid peroxidation increased in NaF-treated mice and pups, as revealed by high liver malondialdehyde levels, while serum total antioxidant status showed a significant decline. These biochemical modifications in NaF-treated mice also correspond histologically with extensive ballooning, hepatocellular necrosis and infiltration of mononuclear cells. These effects were not observed in controls.     

Effects of sodium fluoride on hepatic toxicity in adult mice and their suckling pups

In this investigation, we have evaluated the effect of sodium fluoride (NaF) on hepatic function in pregnant and lactating mice and their suckling pups. Experiments were carried out on female Wistar mice given 500 ppm sodium fluoride (226 ppm fluoride ion) in their drinking water from the 15th day of pregnancy until day 14 after delivery. All mice were sacrificed on day 14 after parturition. Our results showed a significant decrease in serum levels of total protein and albumin, a marked hypoglycaemia and a significant decline in serum cholesterol and triglyceride levels in fluoride-treated mice and their pups. Whereas globulin and biluribin levels in serum were not significantly changed by NaF treatment. On the other hand, serum transaminase activities (aspartate transaminase; alanine transaminase), which well known as markers of liver function, were elevated indicating hepatic cells’ damage after treatment with fluoride. Lipid peroxidation increased in NaF-treated mice and pups, as revealed by high liver malondialdehyde levels, while serum total antioxidant status showed a significant decline. These biochemical modifications in NaF-treated mice also correspond histologically with extensive ballooning, hepatocellular necrosis and infiltration of mononuclear cells. These effects were not observed in controls.     

鹰嘴豆籽粒清蛋白和球蛋白等电点、相对分子量的测定

测定鹰嘴豆Kabuli类型和Desi类型籽粒的清蛋白和球蛋白的等电点,并用凝胶过滤色谱和SDS—PAGE分析总蛋白和清蛋白、球蛋白的组成以及亚基的相对分子量。结果表明：Kabuli类型和Desi类型籽粒清蛋白和球蛋白的等电点分别是5．4、4．0和5．2、4．0;鹰嘴豆籽粒贮藏蛋白经凝胶过滤色谱出现8个蛋白峰,而SDS—PAGE电泳图谱上都出现13条主要亚基带;鹰嘴豆籽粒总蛋白、清蛋白、球蛋白亚基条带分布与大豆相应蛋白亚基条带差异较大;Kabuli类型籽粒球蛋白的亚基数目及其相对分子量与Desi类型非常相似,但两种类型间清蛋白亚基数目及其相对分子量存在较大差异。     

Influence of thymic preparations on the result of experimental infection with Taenia crassiceps (Zeder, 1800) in ICR mice

Thymalin (Thymarin) and T-activin--thymic preparations of polypeptidic character--were used for influencing the parasitic infection in a model system mouse--Taenia crassiceps. A single subcutaneous application of 100 micrograms of Thymalin per mouse at the day of infection resulted in a decrease (by 54.9%) in the number of cysticerci in peritoneal cavity of experimental mice compared with the controls. Administration of Thymalin with T. crassiceps larval homogenate at various intervals before and after infection resulted in a statistically significant increase of the level of specific antibodies in the serum of infected mice, this increase, however, did not correlate with the corresponding protective effect. Immunosuppressant azathioprine, injected subcutaneously from 7th to 3rd day preceding infection at a dose of 100 micrograms resulted in a significant increase in the number of T. crassiceps larvae in the peritoneal cavity of experimental mice compared with the controls (by 48.7%). T-activin, injected subcutaneously to mice, immunosuppressed by azathioprine, led to a restoration of resistance of mice to T. crassiceps infection. Subcutaneous application of T-activin alone had a significant protective effect (decrease in cysticerci number by 53.7% in comparison with the controls). Correlation of the level of specific antibodies in the serum of infected mice, value of spleen index and number of T. crassiceps cysticerci in peritoneal cavity of mice was not detected.     

A study of the possible interconversion of hexachlorocyclohexane stereoisomers on chickpea

A field trial was conducted to study (i) whether there is interconversion of stereoisomers of hexachlorocyclohexane (HCH) on a plant and (ii) the rate of dissipation of lindane on chickpea in a sub-tropical climate. The lack of formation of the beta and delta isomers on application of pure alpha- or gamma-HCH showed that these stereoisomers of HCH did not interconvert on chickpea. The residues of the alpha and gamma isomers dissipated rapidly on chickpea leaves with half-lives of three and four days respectively.     

Electrocorticogram disturbances detected in rats exposed from early stages of life to residual doses of lindane

Functional brain alterations induced by lindane were examined in Rat chronically exposed to low doses of lindane (1 and 2 μg L⁻¹ in drinking water) from conception. Histological and electrophysiological investigations were conducted at 14 weeks of age. Lindane did not induce histological changes. It did not significantly modify the sleep-wakefulness cycle and EEG did not show major alterations. The spectral EEG analysis, by recording cortical variations in both energy spectrum and energy levels of different frequency bands, showed an increase in the 11-15 Hz activity in both groups exposed to lindane. This activity was characterised by spindles well-depicted during slow wave sleep or associated with fast activity during wakefulness and theta activity in paradoxical sleep. These data suggest that chronic exposure to lindane doses as low as 1 μg L⁻¹ in drinking water could lead to central electrophysiological effects possibly involving GABA-benzodiazepine mechanisms.     

The dynamics of eosinophilia in concurrent infections with Trichinella spiralis Owen, 1835 and Toxascaris leonina Linstow, 1909

The concurrent infection with larvae of Trichinella spiralis and eggs of Toxascaris leonina was studied under various conditions using 75 male white mice. The changes in content of eosinophilic leucocytes in the blood, as well as the total number and distribution of larvae of both parasites in different body tissues were demonstrated. The primary infection with Toxascaris leonina caused an increase in the number of eosinophilic leucocytes from day 4 p.i., whereas the infection with Trichinella spiralis larvae induced an increase only from day 7 p.i. An antagonism was observed between the two parasite species: the primary infection with T. leonina led to a decrease in the total number of muscle larvae of T. spiralis, and, vice versa, the primary infection with T. spiralis suppressed the development of T. leonina.     

Effect of short term exposure of fenvalerate on biochemical and haematological responses in Labeo rohita (Hamilton) fingerlings

Experiment was carried out to determine the median lethal concentration (LC₅₀) of fenvalerate to Labeo rohita fingerlings. After determining the LC₅₀ value of fenvalerate, a sub-lethal concentration (1/3rd of LC₅₀) of fenvalerate was exposed for 15 days. Significant alterations in SOD (P < 0.05) activity of liver and gill was observed due to fenvalerate. Catalase activity in gills of fishes was also affected significantly (P < 0.05). WBC, NBT and Hct values were reduced significantly in fenvalerate exposed fishes as compared to control group, whereas blood glucose level showed higher values in fenvalerate exposed group. Serum total protein and albumin were also reduced significantly as a result of fenvalerate exposure. Significant increase in the serum GOT, serum GPT, creatinine, triglyceride and serum ACP was noticed after 15 days of fenvalerate exposure. Results indicated that short term exposure of fenvalerate can induce biochemical and haematological alterations causing stress to L. rohita fingerlings.     

The effects of deltamethrin on some serum biochemical parameters in mice

Sixty white male mice were used in this study. Three groups, each comprising 20 mice were established. The control group (Group 1) was provided ad libitum pellet feed. On the other hand, the experimental groups, namely, Groups 2 and 3 were given pellet feed containing deltamethrin throughout the day, so that the animals were administered doses of 7.5 and 30 mg/kg/body weight/day, respectively. Blood samples were collected from all groups on the 15th, 30th, 45th, and 60th days of the experiment for measurement of serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT), alcaline phosphatase (ALP), amylase and cholinesterase activities, and levels of glucose, urea, creatinine, triglyceride, cholesterol, calcium, phosphor, sodium, potassium, and chloride. According to data obtained, on the 15th day of the study, compared to the control group, statistically significant increase in urea, cholesterol, ALP, cholinesterase, calcium, and potassium levels/activities, and significant decrease in SGOT activity and chloride levels in Group 2, and significant increase in cholesterol, ALP, cholinesterase, calcium, potassium and chloride levels/activities in Group 3, and significant decrease in SGOT activity in Group 3 were determined. On the 30th day of the study, in comparison to the control group, triglyceride and cholesterol levels and ALP activity were determined to be significantly increased in the Group 2, whereas SGOT activity were significantly reduced in Group 2, and triglyceride and cholesterol levels were demonstrated to be significantly increased and SGOT activity was significantly reduced in Group 3. On the 45th day of the study, compared to the controls, significant increase in cholesterol and sodium levels, and significant decrease in triglyceride levels and ALP activity in Group 2, significant increase in creatinine, cholesterol and sodium levels and cholinesterase activity, and significant decrease in glucose, SGPT, ALP and phosphor levels/activities were detected in Group 3. On the 60th day, in other words, in the last period of the study, ALP activity, and triglyceride, calcium, and phosphor levels were determined to be significantly increased and significant decrease in amylase activity in Group 2. Furthermore, significant increase in triglyceride, ALP, amylase, calcium, phosphor, and potassium levels/activities, and significant decrease in glucose and creatinine levels were observed in Group 3. However no correlation was determined to exist between the changes were found to be statistically significant, and the administration dose and duration of deltamethrin in all periods and groups.     

蝶蛹金小蜂寄生对菜粉蝶和玉带凤蝶蛹血细胞数量和组成的影响

以血球计数板较系统地考查了菜粉蝶和柑桔凤蝶雌雄蛹被蝶蛹金小蜂寄生后浆血细胞和颗粒血细胞数量的时间动态变化,以明确该蜂寄生对其寄主血细胞数量和组成的影响.结果表明,菜粉蝶蛹被寄生后,其血细胞总数除寄生后2天外均极显著高于同期未寄生蛹,最多的约高出20倍;除被寄生后0.5和5天的寄生蛹的血细胞组成与同期未寄生蛹无显著差异外,寄生后1～ 4 天雌雄寄生蛹的浆血细胞所占比例均显著低于同期未寄生蛹,而颗粒血细胞所占比例则反之.玉带凤蝶寄生蛹的血细胞总数在寄生后0.5 ～ 3天与同期未寄生蛹相比均无显著差异,但寄生后4 ～ 5天却显著升高,最多的约高出3倍;寄生后0.5 ～ 5天的寄生蛹浆血细胞所占比例均显著低于同期未寄生蛹,而颗粒血细胞所占比例恰反之.可见,该蜂寄生在一定时间内不仅能引起其两种寄主血细胞总数和颗粒血细胞所占比例明显增高,而且能导致浆血细胞所占比例明显下降.     

Experimental infection of immunocompetent and immunodeficient mice with Encephalitozoon cuniculi

An experimental infection with the microsporidian Encephalitozoon cuniculi Levaditi, Nicolau et Schoen, 1923 was studied using a model of immunocompetent BALB/c mice and immunodeficient SCID mice. The course of infection after intraperitoneal inoculation of E. cuniculi spores was evaluated using the presence of spores in peritoneal macrophages as a criterion. First significant decrease in the proportion of infected cells was recorded on day 9 post infection (p.i.) in BALB/c mice. From day 14 p.i. no spores were observed in macrophages from BALB/c mice, while the number of infected macrophages from SCID mice increased until the death of the mice. The natural killer (NK) cell activity of mouse splenocytes was compared with the production of interferon gamma (IFN-gamma) by these cells. While in BALB/c mice NK activity peaked on days 9 and 14 p.i., in SCID mice the marked increase of NK activity was recorded close before death of mice, on day 21 p.i. in correlation with the production of IFN-gamma. Production of specific antibodies was demonstrated from day 9 p.i. in sera from BALB/c mice. It is concluded that intraperitoneal infection of SCID mice with spores of E. cuniculi results in the marked increase in the number of peritoneal exudate cells and in the percentage of infected cells close before death of mice. Neither high activity of NK cells nor increased production of IFN-gamma are sufficient for the recovery of SCID mice from an E. cuniculi infection.     

Influence of methabenzthiazuron on ATP-level and protein synthesis in wheat

Spring wheat (Triticum aestivum L. “Kolibri”) was grown in vermiculite treated with the photosynthesis inhibiting herbicide methabenzthiazuron (1-(benzothiazol-2-yl)-1,3-dimethylurea) either before germination or when the plants were 13 days old. The plants were analyzed from 2 days before until 11 days after treatment or up to a plant age of 23 days.The results are interpreted to fit the concept of a “shade adaptation reaction” caused by a herbicidal photosynthesis inhibition. Soluble reducing sugars have been found to decrease 4 hr after treatment and to stay at a low level throught the experiment. The ATP level was decreased 1 day after treatment but increased above control values 4 days later. This increase was accompanied by a decrease of the chlorophyll $\text{a}\text{b}$ ratio. The explanation is given that the ATP level was first decreased because of a lowered carbohydrate supply for substrate and oxidative phosphorylation, and was afterwords increased as a result of an increased cyclic photophosphorylation activity.The soluble protein content and the incorporation of [¹⁴C]leucine into protein were increased 4 days after herbicidal treatment. The total protein was slightly decreased beginning 1 day after treatment. The nitrate concentration and the in vitro nitrate reductase activity were both increased 1 day after treatment. The increase of the nitrate concentration occurred in two phases: a first increase by 50% 1 and 2 days after treatment and a second, much stronger increase beginning on the third day. The first increase is interpreted as the result of a decreased in vivo nitrate reductase activity. The second increase possibly was the result of an increased rate of nitrate uptake.     

Proteome analysis of Fusarium infection in emmer grains (Triticum dicoccum)

The fungal infection of emmer grain (Triticum dicoccum) with Fusarium graminearum and Fusarium culmorum was investigated at the level of the proteome. High‐resolution two‐dimensional gel electrophoresis and mass spectrometry were used to identify proteins that were differentially expressed in response to fungal infection of emmer. Moreover, the effects of natural field conditions at two locations on the carbon and nitrogen contents and the mycotoxin concentration of emmer grains were evaluated. Inoculation of emmer with a mixture of the two Fusarium species led to infection of the ears, with deoxynivalenol concentrations up to 10 mg kg^?1 in the grain. Carbon concentration and crude protein content were not significantly changed, but 10 distinct proteins changed in abundance. Stress‐related proteins, such as a serine protease inhibitor, a thaumatin‐like protein that reduced fungal growth and the starch hydrolysis β‐amylase increased upon infection, whereas the stress‐related proteins peroxidase, peroxiredoxin, a starch‐synthesis protein (a glycosyltransferase) and a fungal cell wall degrading protein (a chitinase) decreased. Furthermore, levels of three storage proteins in emmer grains were affected by Fusarium infection: α‐gliadin decreased and two globulins increased upon infection.     

In vivo biochemical changes in liver and gill of Clarias batrachus during cypermethrin exposure and following cessation of exposure

The sublethal effect of a synthetic pyrethroid, cypermethrin on total protein, amino acids, ammonia, glycogen, and enzymes like aminotransaminases (AIAT, AAT), glutamate dehydrogenase, and glycogen phosphorylases (a and ab) was studied in physiological important tissues viz; liver and gill tissues of freshwater teleost air breathing fish, Clarias batrachus. The study was conducted during exposure of 1/3 (33%) of LC₅₀ concentration and followed by cessation of exposure. Thirty-six fish were exposed to 0.07 mg/L cypermethrin for 10 days. After 10 days, 18 fish were released to freshwater and kept in the same for 10 days (recovery group). Thirty-six fish were kept in freshwater as control batch. Protein content in liver tissues decreased at the end of 1st and 5th day followed by slight increase at the end of 10th day. Gill tissue showed statistical significant decrease (P < 0.001) in protein content during exposure period of 10 days. Recovery in protein content was observed to a large extent in both the tissues. Total free amino acids were increased in liver and gill tissues throughout the treatment period, recovery response was seen after cessation of exposure. Ammonia level was decrease in both the tissues throughout the exposure period except in liver tissue at the end of 1st day of exposure. Recovery response was exhibited by both the tissues. A decreased in glycogen content of liver tissue was observed during exposure period, gill tissue also showed decrease in glycogen at the end of 1st and 5th day followed by increase at the end of 10th day of exposure period. When the fish were transferred to freshwater, recovery in glycogen content was noted. The activity level of alanine, aspartate aminotransaminase, glutamate dehydrogenase, and phosphorylases (a, ab) was increased in both the tissues, followed by recovery response after released of fish into freshwater. The present study showed that cypermethrin caused alterations in certain biochemical mechanisms of C. batrachus. This fish indicated recovery response when transferred to cypermethrin free water.     

Chemical modifications of the insecticide binding sites on human serum albumin: Role of indole,bilirubin, and fatty acid binding sites

Interaction of carbamate and organophosphorus insecticides with chemically modified human serum albumin was studied by solubilization and difference spectra of bound insecticides and quenching of albumin fluorescence. Chemical modification involved oxidation of 1 tryptophan and 4 histidine residues, acetylation of 4 tyrosine and 26 lysine residues, and reaction of 7 arginine residues with 1,2-cyclohexanedione. There was a decrease in binding due to modification of arginine, tryptophan, and tyrosine residues and an increased binding due to lysine acetylation. The presence of bilirubin and octanoate also decreased the binding of insecticides. Changes in fluorescence of bound ANS due to binding of insecticides to albumin indicate localized perturbation of albumin conformation. The binding of insecticides was not affected by palmitate at physiological concentrations (molar ratio less than 2) although higher fatty acid concentrations caused a decrease. These preliminary observations suggest that warfarin, indole, and bilirubin sites are probably among the multiple insecticide binding sites.     

The influence of <Emphasis Type="Italic">Aphanomyces cochlioides</Emphasis> on selected physiological processes in sugar beet leaves and yield parameters

Alterations in some physiological processes in source leaves of sugar beet—such as chlorophyll and carbohydrate concentrations, stomatal conductance, rate of net photosynthesis and transpiration, and activity of the photosynthetic apparatus during root interaction with Aphanomyces cochlioides, were investigated. The influence of time of infection on plant health, yield quality and quantity was also examined. Plants were infected at different times of their growth period: on the sowing day and 4 or 8 weeks after sowing. A variation treatment, with non-pelleted seeds infected on the sowing day, was also analyzed. The experiment showed that development of disease symptoms depends on the time of infection and seed protection. A significant root yield decrease was observed in case of late infection, as compared to the yield of plants infected on the sowing day. The fresh weight of leaves was significantly increased where there was late infection. The infected plants showed a lower content of K⁺, Na⁺ and α-amino-N than did the controls. Infection by A. cochlioides induced chlorophyll degradation mostly in older leaves with the occurrence of natural senescence processes. Chlorophyll fluorescence parameters indicated that the photosynthetic apparatus of younger leaves was more sensitive to pathogen infection, when compared to older ones. The photochemical efficiency of photosystem II was reduced in young leaves mainly due to disturbance of the water-splitting system. In plants grown from non-pelleted seeds a strong impairment of PSII was observed only in those leaves which developed during early pathogen infection. In young leaves of plants infected in the fourth week after sowing, inhibition of the rate of net photosynthesis was correlated with the increase in intercellular CO₂ concentration, indicating some disturbance in the carbon assimilation phase. In mature leaves of late infected plants the reduction of photosynthesis net rate was associated with a decrease of stomatal conductance and an increase of diffusion resistance to CO₂ and H₂O, which was also the cause of the transpiration rate inhibition. When the leaves developed during early infection, an increase of specific leaf weight and accumulation of carbohydrates was observed. In mature leaves of non-protected plants infected on the sowing day, the recovery of all physiological processes was observed together with a diminution of disease symptoms.     

Oxidative damage in bone and erythrocytes of suckling rats exposed to 2,4-dichlorophenoxyacetic acid

Nowadays, people’s exposure to pesticides such as 2,4-dichlorophenoxyacetic acid (2,4-D) is increasing continuously. This compound is suspected to produce in excess free radicals which have adverse effects on human health causing several cell alterations in the organism. The present study investigated oxidative stress in the bone and erythrocytes of suckling rats whose mothers were treated with 2,4-D. Experiments were carried out on adult Wistar rats given 600 mg/L of 2,4-D in their drinking water from the 14th day of pregnancy until day 14 after delivery. Exposing dams to 2,4-D caused disorders in the bone of their progeny. Indeed, it induced changes in bone mineralization, especially calcium and phosphorus levels. Moreover, total tartrate-resistant acid phosphatase, which reflected bone resorption, was enhanced while total alkaline phosphatase, which reflected bone formation, was reduced suggesting that this herbicide accelerated bone resorption. The impairment of bone function corresponded histologically.Rats exposed to 2,4-D showed in both bone and erythrocytes an increase in malondialdehyde, advanced oxidation protein products and protein carbonyl levels and a decrease in non-enzymatic (glutathione, non-protein thiol, and vitamin C) and enzymatic (superoxide dismutase, catalase, and glutathione peroxidase) antioxidant system.     

Prallethrin induced serum biochemical changes in Wistar rats

The present study was designed as a repeated dose 28-day oral toxicity study in rodent. All the rats were randomly divided into five groups (C1, C2, T1, T2 and T3) each containing 10 Wistar rats (5 male and 5 female). Group C1 served as control as no treatment was administered. Group C2 was administered groundnut oil (1 ml/100 g b.wt) and served as vehicle control. Group T1 was put on high dose 153.33 mg/kg b.wt (LD50/3), while group T2 received intermediate dose of 92 mg/kg b.wt (LD50/5), and group T3 was administered low dose of 46 mg/kg b.wt (LD50/10) of Prallethrin suspended in 1 ml/100 g b.wt of groundnut oil. Blood samples were collected from all groups on the 7th, 14th, 21st and 28th day of the experiment for measurement of serum glucose, serum urea, serum triglyceride, serum cholesterol, serum aspartate aminotransferase (AST), serum alanine aminotransferase (ALT) and serum alkaline phosphatase (ALP). According to data obtained on the 7th day of the study, no statistically significant change in any of the treatment groups was observed as compared to the control group. On the 14th day of the study, in comparison to the control group, triglyceride level and ALP activity were found to be significantly increased in the group T1 female and group T1 male rats respectively. On the 21st day of the study, compared to the controls, significant increase in cholesterol and ALP levels were present in both T1 and T2 females and in addition to this total protein and triglycerides levels were also significantly increased in group T1 female rats. In group T1 male total protein, triglycerides, ALT and ALP activity was found to be increased significantly as compared to healthy control group. On the 28th day, all the recorded biochemical parameters were found to be significantly increased, except BUN and AST in group T1 female rats. In group T2 female rats, significantly increased cholesterol, ALT and ALP levels were observed. In group T3 female rats, none of the parameters were found to be significantly affected. Among male rats, only total protein level was found to be increased in groups T2 and T3. Whereas, total protein, triglyceride, ALT and ALP were significantly elevated in group T1 male rats at the end of the study. In conclusion, the results of this study demonstrate that subacute oral administration of Prallethrin; at dose levels of 1/3 LD50 and 1/5 LD50 for 28 days induces moderate toxic effects on different biochemical parameters.     

Influence of drought, salt stress and abscisic acid on the resistance of tomato to Botrytis cinerea and Oidium neolycopersici

Abiotic stress may affect plant response to pathogen attack through induced alterations in growth regulator and gene expression. Abscisic acid (ABA) mediates several plant responses to abiotic stress. The effects of drought, salt stress and ABA on the interaction of tomato ( Lycopersicon esculentum ) with the biotrophic fungus Oidium neolycopersici and the necrotrophic fungus Botrytis cinerea were investigated. Drought stress resulted in a twofold increase in endogenous ABA as well as a 50% reduction in B. cinerea infection and a significant suppression of O. neolycopersici on tomato cv. Moneymaker. Salt stress did not affect B. cinerea infection, but significantly reduced infection by O. neolycopersici , with no obvious increase in endogenous ABA. Compared with the wild type, the ABA-deficient sitiens mutant was more resistant to O. neolycopersici and B. cinerea . Exogenous ABA resulted in increased susceptibility of sitiens to both pathogens, but did not increase the basal susceptibility of wild-type plants. It is concluded that, in tomato, drought and salt stress stimulate different, but possibly overlapping, pathogen-defence pathways which may not necessarily involve ABA. Meanwhile, basal endogenous ABA levels suppress the resistance of tomato to O. neolycopersici and B. cinerea , but an ABA increase above the basal level, resulting from exogenous application, does not increase susceptibility to these pathogens.