Effect of stalk damage on growth and yield of certain maize cultivars by the maize stalk borer Chilo partellus

The effects of different degrees of stem tunneling caused by different levels of artificial infestation by the larvae of Chilo partellus (Swinhoe) on growth and yield of 4 maize cultivars were studied. The susceptible Inbred A suffered much more tunneling than ICZ1-CM, ICZ2-CM and Katumani Composite B. This tunneling influenced significantly the plant growth of all the four cultivars. There was a significant negative correlation between tunneling and yield for the cultivars Inbred A and Katumani Composite B, but such a relationship was not significant for ICZ1-CM and ICZ2-CM. Such differences in the relationships between tunneling and yield among the 4 cultivars are due to different degrees of tunneling caused by C. partellus larvae to the plants of these cultivars.

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Résumé L'étude a porté sur la croissance et la production avec différents niveaux de minage des tiges de 4 cultivars de maïs, lors de divers degrés de contamination artificielle par des chenilles de C. partellus. Le cultivar sensible Inbred A souffre plus des mines de C. partellus que ICZ1-CM, ICZ2-CM et Katumani composite B. Les mines influent significativement sur la croissance des 4 cultivars. Il y a une corrélation négative significative entre le minage des tiges et la production pour les cultivars Inbred A et Katumani composite B, mais la relation n'est pas significative pour ICZ1-CM et ICZ2-CM. Les différences entre le minage des tiges et la récolte des 4 cultivars sont dues aux différents degrés de minage des tiges de ces cultivars par C. partellus.

     

Resistance in certain maize cultivars to first and third-instar Chilo partellus larvae

The resistance/susceptibility levels of ten maize (Zea mays L.) cultivars to neonates and 3rd-instar larvae of Chilo partellus (Swinhoe) (Lepidoptera: Pyralidae) were measured in the field and screenhouse experiments. The maize cultivars tested were: Inbred A, Mp 704, V-37, Population 10, Hybrid 511, Katumani Composite B, ER-29 SVR, Poza Rica 7832, ICZ2-CM, and MMV 400. Most cultivars were found susceptible to 3rd-instar larvae based on the incidence of dead heart symptoms, foliar feeding and stem tunnelling caused by stem borers in both the field and screenhouse experiments. However, the maize cultivars V-37, MMV 400 and Poza Rica 7832 sustained significantly lesser damage than the other cultivars when infested with neonates or 3rd instar larvae.The screenhouse experiments conducted with five maize cultivars, i.e. Inbred A, Mp 704, V-37, ER-29 SVR, and Poza Rica 7832 showed that neonates fed less on the resistant than the susceptible maize cultivars but feeding by the 3rd instars was equally high on all the maize cultivars except Mp 704 on which the larvae fed less than the others. In the cultivars infested with neonates, the mean period for 50% moth emergence P₅₀ was longest on Mp 704 followed by Poza Rica 7832, ER-29 SVR, V-37 and Inbred A. In the cultivars infested with 3rd-instars, P₅₀ was longest for Poza Rica 7832 followed equally by the remaining cultivars.On the basis of the evidence presented we here conclude that neonates of C. partellus are sensitive to the growth inhibiting effects of the resistant maize cultivars Mp 704, V-37, and Poza Rica 7832 but the older larvae are insensitive to these effects of Mp 704 and V-37 but not of Poza Rica 7832.     

Silicon impedes stalk penetration by the borer Eldana saccharina in sugarcane

Many plants grown in soils amended with silicon (Si) display increased levels of resistance to attack by insect herbivores. This study aimed to determine if Si treatment impeded Eldana saccharina Walker (Lepidoptera: Pyralidae) stalk penetration and subsequent damage, as well as borer mass gain, on the node and internode of a susceptible (N11) and a resistant (N33) sugarcane cultivar. Sugarcane [Saccharum spp. (Poaceae)] cultivars were grown in a pot trial in Si‐deficient river sand, with (Si+) and without (Si–) calcium silicate. Sugarcane was infested with 2‐week‐old E. saccharina larvae and harvested at four times, 24, 48, 72, and 96 h after infestation. Silicon‐treated plants showed significant increases in Si content compared to controls, and the external rind was significantly harder for Si+ cane than Si– cane. Silicon treatment significantly decreased borer penetration, stalk damage, and larval mass gain. The results are consistent with the hypothesis that Si contributes to sugarcane stalk borer resistance by impeding larval penetration. Silicon appears to contribute to the suppression of E. saccharina directly through reduced larval growth and feeding damage to the crop, and indirectly by delaying stalk penetration, resulting most likely in increased exposure time of young larvae to natural enemies, adverse climatic factors, or control measures that target young larvae (e.g., insecticides).     

Mechanism of resistance to the spotted stalk borer,Chilo sacchariphagus,in the sugarcane cultivar R570

Resistance in sugarcane [Saccharum spec. (Poaceae)] to the spotted stalk borer, Chilo sacchariphagus (Bojer) (Lepidoptera: Pyralidae), was studied by comparing feeding behaviour on resistant cv. R570 and susceptible cv. R579. In a field survey, the feeding behaviour of C. sacchariphagus larvae was described to identify their feeding sites on the plant. In a greenhouse artificial infestation study, we compared the establishment of larvae on potted plants. In laboratory choice and no‐choice experiments, we studied the establishment of larvae on plant organs (stalk, sheath, leaf spindle). Study of the feeding behaviour showed that: (1) first to fourth instars are able to feed on stalk, sheath, and leaf spindle, (2) boring into the stalk occurs mostly in the four uppermost internodes, and (3) most young larvae bore through the abaxial surface of leaf sheaths to reach the stalk. In greenhouse experiments, we observed an early two‐fold reduction of the number of larvae on R570 plants within the first 48 h after infestation. In laboratory experiments, larval antixenosis was demonstrated at the abaxial surface of R570 leaf sheath, but was observed neither in the leaf spindle nor in the stalk. First, second, and third instars were susceptible to this antixenosis. We hypothesize that the main resistance mechanism in R570 is an early reduction of larval establishment on plants, due to antixenosis located at the abaxial surface of leaf sheaths.     

Difference in the time of mating activity between host-associated populations of the rice stem borer, Chilo suppressalis (Walker)

Mating activities of the rice stem borer, Chilo suppressalis, were compared between rice‐ and wateroat‐feeding populations, and two potential temporal factors that may act as reproductive barriers were examined. Seasonal data of the number of moths attracted to pheromone traps showed that the peak of emergence at the rice field was approximately 10 days earlier than that at the wateroat vegetation in the first flight season, although there was a broad overlap of emergence at the two locations. Both field observations and a laboratory experiment showed that moths from the rice field started mating earlier than those from the wateroat vegetation. However, whereas the difference was distinctive in the laboratory experiment, mating activity at the wateroat vegetation shifted significantly to an earlier time phase than that observed in the laboratory. Body size data showed that the male moths attracted to the pheromone traps at the wateroat vegetation were significantly larger than those at the rice field, suggesting that the traps at the two locations mainly attracted moths originating from different host plants. However, pheromone‐trapped males at the rice field were significantly larger than those reared from overwintering samples. These results support the idea that males from the wateroat vegetation migrate to the rice field. The differences in seasonal and temporal mating activity and their effects on development of reproductive isolation between host‐associated populations are discussed.     

Sex pheromone of the red clover casebearer moth,Coleophora deauratella,an invasive pest of clover in Canada

The red clover casebearer, Coleophora deauratella Lienig & Zeller (Lepidoptera: Coleophoridae), is an invasive pest of Trifolium species (Fabaceae) in Canada. We identified candidate sex pheromone components from female pheromone gland extracts using coupled gas chromatographic–electroantennographic analysis detection. Three compounds elicited an electrophysiological response from antennae and were identified as: (Z)‐7‐dodecenyl acetate, (Z)‐5‐dodecenyl acetate, and (Z)‐7‐dodecen‐1‐ol. Field tests of the candidate pheromone components revealed that males were attracted to a binary mixture of (Z)‐7‐dodecenyl acetate and (Z)‐5‐dodecenyl acetate. Male moth trap capture was greatest in traps baited with lures containing 100:10 or 100:20 ratios of these pheromone components, respectively. Trap capture was reduced when (Z)‐5‐dodecenyl acetate was present below 10 or above 20% of (Z)‐7‐dodecenyl acetate. Equal numbers of male moths were captured in traps baited with 10, 100, and 1 000 μg of the attractive binary mixture. These findings allow for the development of a pheromone‐based monitoring system for this invasive pest of clover in Canada.     

Antixenosis and larval and adult dispersal in the Mediterranean corn borer,Sesamia nonagrioides,in relation to Bt maize

Sesamia nonagrioides Lefèbvre (Lepidoptera: Noctuidae) is a key pest of maize [Zea mays L. (Poaceae)] and a main target of Bt maize in the Mediterranean area. To choose the most suitable non‐Bt refuge strategy for preventing or delaying resistance development in this maize borer, we examined its biology and behaviour. No antixenotic effects were found on numbers of eggs and egg batches per plant in choice (Bt vs. non‐Bt plants) and no‐choice assays. However, a greater ratio of young larvae dispersed from Bt than from non‐Bt plants. In addition, larvae that hatched on Bt plants tended to disperse more than those that hatched on non‐Bt plants, particularly during young growth stages. Many adults, especially females, could fly at least up to 400 m, as was found in a dispersal study with rubidium‐marked adults. The stimulation of larval dispersal by the Bt trait and the dispersal capacity of adults might compromise the efficacy of seed mixtures as an insecticide resistance management strategy.     

龙柏精油对小菜蛾的生物活性

龙柏精油对小菜蛾Plutella xylostella(L.)的室内生物活性测定结果表明,熏蒸作用是龙柏精油对小菜蛾的主要作用方式,熏蒸实验中当龙柏精油浓度为5.00 mg/L2、.50 mg/L时,处理后48 h小菜蛾2龄幼虫的校正死亡率分别为92.33%、80.29%。龙柏精油对小菜蛾具有较强的非选择性拒食作用和产卵忌避作用,但由于精油的挥发性效果不持久。当龙柏精油浓度为5.00 mg/L和2.50 mg/L时,24 h小菜蛾的产卵忌避率分别为80.45%和77.42%;而48 h则降为72.30%和61.79%。当龙柏精油浓度为5.00,2.50和1.25 mg/L时,24 h的非选择性拒食率分别为86.70,74.36和70.93%,48 h的非选择性拒食率分别降为82.36,71.40和60.40%。龙柏精油对小菜蛾具有一定的触杀活性,当龙柏精油浓度为5.00 mg/L时效果最好,24 h和48 h的校正死亡率分别为60.00%和76.67%。     

The importance of the behaviour of young larvae in sorghum resistance to Chilo partellus

Management of spotted stem borer, Chilo partellus (Swinhoe) by the use of resistant cultivars is being developed at ICRISAT. Different cultivars show resistance based on several mechanisms, one of which affects the establishment of first instar larvae in the plant whorl. However, it has been found that low establishment is a factor associated with resistance only in some cultivars and not in others. A number of physical and chemical plant factors are associated with preferential establishment of the young larvae in the leaf whorl. Among the physical characteristics, erect leaves and curled leaf bases are involved in larval establishment. Detailed chemical analysis of surface extracts showed that the concentration of one compound in the wax is related to resistance at this stage and assessment of physical and chemical plant characters has been used to predict resistance.

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Résumé L'Institut International de Recherches sur les Cultures en Régions Semi-Arides (ICRISAT) étudie la protection contre C. partellus Swinhoe par l'utilisation de cultivars résistants. Différents cultivars présentent une résistance à différents stades de croissance de la plante, et à différents stades de l'insecte. La résistance du sorgho à C. partellus dépend de plusieurs mécanismes, l'un d'eux conditionnant l'installation des chenilles du premier stade dans le verticille de la plante. Cependant, la lenteur de l'installation d'est un facteur lié à la résistance que chez quelques cultivars. Plusiers facteurs physiques et chimiques sont associés à l'installation préférentielle des jeunes chenilles dans le verticille foliare. Parmi les caractères physiques, le port érigé des feuilles, la présence de poches à leur base et les cires superficielles sont impliqués dans l'installation des chenilles. Une analyse chimique détaillée d'extraits des structures superficielles a montré que la concentration d'une substance, le C32 marqueur de la lignée résistante IS 2205, était 2 fois plus faible que dans les lignées sensibles IS 1151 et CSH 1.

     

Tolerance of Bt corn (MON 810) to maize stem borer, Chilo partellus (Lepidoptera: Pyralidae)

Transgenic corn (MON 810), expressing the Bacillus thuringiensis (Bt) protein, Cry1Ab, was evaluated under greenhouse conditions for its tolerance to the maize stem borer, Chilo partellus. Bt corn (MON 810) provided effective protection against the stem borer even under a high level of larval infestation in the greenhouse. The observed tolerance is examined and discussed in the light of the susceptibility of C. partellus to the Cry1Ab protein in laboratory bioassays. The implications of the tissue concentrations of Cry1Ab in MON 810, and baseline susceptibility recorded in the current study, for insect-resistance management are discussed.     

九种植物精油对腌肉及咸鱼害虫大头金蝇的杀卵作用

为开发腌肉和咸鱼害蝇的安全性杀卵剂,采用改进的浸卵法,进行了9种植物精油对大头金蝇的杀卵活性测定.结果表明:肉桂、丁香、八角茴香3种植物精油较为有效,它们的杀卵毒力(LC50)依次为0.428、1.605和2.489mg.ml-1,以肉桂油的毒力最强.通过GC/MC成分分析,从肉桂油检出22个成分,主成分桂皮醛占92.33%.合成桂皮醛(含量97.33%)的毒力为0.281mg.ml-1,略高于肉桂油,表明桂皮醛是肉桂油的主要杀卵活性成分,可替代肉桂油作为害蝇杀卵剂利用.     

Larval dispersal of the invasive fall armyworm,Spodoptera frugiperda,the exotic stemborer Chilo partellus,and indigenous maize stemborers in Africa

Larval dispersal either through ballooning or crawling results in a redistribution of the insect population and infestations within and between plants. In addition, invasive species, such as the fall armyworm (FAW), Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae), and the exotic stemborer Chilo partellus (Swinhoe) (Lepidoptera: Crambidae), may displace indigenous stemborers on maize in Africa. To test whether larval dispersal activity may play a role in the displacement of indigenous stemborers, larval dispersal was compared between FAW, C. partellus, and the indigenous species Busseola fusca (Fuller) and Sesamia calamistis (Hampson) (both Lepidoptera: Noctuidae). Twenty potted maize plants were infested with one batch of eggs either from stemborers (B. fusca, S. calamistis, or C. partellus) or from FAW and monitored in the greenhouse for ballooning activities. After egg hatching, both ballooning and non-ballooning larvae were identified according to species and counted. FAW neonate larvae had greater potential for ballooning off than stemborers, irrespective of species. For each species, more females dispersed than males, and their survival rate was higher than that of non-ballooning larvae. In addition, plant-to-plant larval movements were studied using 6.25-m² plots of caged maize in a completely randomized design with five replicates. FAW was found to have wider dispersal and plant damage potential than any of the stemborer species. In conclusion, in contrast to C. partellus, the invasive characteristic of FAW can be explained, in part, by its higher larval dispersal activity compared to stemborers. This difference in larval dispersal might also be considered in sampling plans for monitoring pest density in the field.     

Reduction of damage by the Mediterranean corn borer, Sesamia nonagrioides, and the European corn borer, Ostrinia nubilalis, in maize fields by a trifluoromethyl ketone pheromone analog

Large‐scale field experiments on the Mediterranean corn borer, Sesamia nonagrioides Lefèbvre (Lepidoptera: Noctuidae), were carried out in 2004–2006 on maize [Zea mays L. (Poaceae)] fields using (Z)‐11‐hexadecenyl trifluoromethyl ketone, an antagonist analog of the pheromone of this species, to evaluate a possible reduction of damage caused by this pest. The effect of the treatments on the European corn borer, Ostrinia nubilalis Hübner (Lepidoptera: Crambidae), a sympatric species, was also determined. Evaluation of the success of the experiments was assessed by counting (i) the number of males caught by pheromone traps in treated and untreated fields, (ii) the number of plants attacked by both insects in both plots, and (iii) the number of larvae present in infested plants in both fields. Effectiveness of the treatment was high for the second generation of the Mediterranean corn borer, the most harmful to the crop (86–90% reduction in the number of plants attacked and 67–98% reduction in the number of larvae per plant in treated fields in comparison to untreated fields), and moderate for the third generation (reduction of 41–71% and 33–77%, respectively). Treatments were also effective for the second generation of the European corn borer (61–75% reduction in the number of plants attacked, 58–78% reduction in the number of larvae found per plant) as well as for the third generation (69–97% and 70–98% reduction, respectively). By plotting the amount of the antagonist remaining on the dispensers after 40–45 days of exposure with time, the mean release rate of the compound was calculated to be 2.2%/day in 2004, 1.95%/day in 2005, and 2.1%/day in 2006, with 26% of the initial compound remaining after 20 days of experimentation. The emission rate appears to cover the flight of the most damaging second generation of both insects. Prospects of using trifluoromethyl ketones as new potential agents for pest control are also outlined.     

Long-term pheromone-mediated mating disruption of the Mediterranean flour moth, Ephestia kuehniella, in a flourmill

Several studies have indicated that mating disruption (MD) successfully reduces population densities of stored product moths, for example, the Mediterranean flour moth, Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae). However, practical issues, such as finding control plots, replication, and lack of similarity between replicates, often incur problems in full-scale investigations and often draw focus from the added results. We here present results from long-term monitoring of E. kuehniella populations in two similar flourmills in Poland, one treated with pheromone for MD and one left untreated and used as control. Pheromone-mediated MD was applied during 2 years. Thirty pheromone dispensers (one per 100 m³ factory volume), each releasing about 2 mg ( Z,E )-9,12-tetradecadienyl acetate per day, were used. Pheromone-baited traps were used to monitor the moth populations in the MD mill and in a nearby untreated mill. The reduction in trap catch during the MD treatment was about 90% or more, compared with the untreated mill or pre-treatment periods of the MD mill. The reduction was larger during the 2nd year of MD than during the 1st year. These results contribute to the picture that MD is an effective method to control moth species infesting stored products.     

Efficacy of Elettaria cardamomum L. (Zingiberaceae) essential oil on the two spotted spider mite,Tetranychus urticae Koch (Acari: Tetranychidae)

Two-spotted spider mite, Tetranychus urticae Koch is the major pest of various plants worldwide. Now the control is dependent on the use of chemical pesticides. Plant compounds are recently known as biopesticides. Essential oil of Elettaria cardamomum was researched on repellent and oviposition inhibition of T. urticae. The LC₅₀ values of fumigant toxicity of this oil on adults and eggs of the two spotted spider mite were 7.26 and 8.82?μL/L air, respectively. Also LT₅₀ value of essential oil at 45?μL/L air was 23.86?h and LT₅₀ value of essential oil at 60?μL/L air was 9.01?h. In addition, different concentrations of the essential oil of E. cardamomum significantly affected oviposition deterrence and repellency of adults. The results of this study indicated that essential oil of E. cardamomum may be considered as a biopesticide to control two spotted spider mites.     

A test of fruit varieties on entry rate and development by neonate larvae of the codling moth,Cydia pomonella

The rate of entry by neonate larvae of the frugivorous codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), into fruit material was investigated. We used no‐choice bioassays in climate‐controlled rooms to assay larval entry across four host plant species (apple, pear, quince, walnut) and three varieties within a single fruit species (apple). Larvae successfully entering apples were reared to adulthood, and we collected tissue samples from apples which were successfully colonized in order to determine sucrose concentrations. This information was used to evaluate differences in adult moth size, development time, and pulp sucrose concentration due to apple variety. Four important findings emerged: (1) neonate larvae had the highest frequency of entry (86% of larvae) into apple fruits, compared with pear (78%), quince (56%), and walnut (32%); (2) the frequency of larval entry into immature apples differed across apple varieties, and larval entry rate was highest in variety Golden Delicious (72%), compared with Granny Smith (46%) and Red Delicious (64%); (3) on average, adult moths were larger and development times were shorter on the variety with the highest entry frequency (Golden Delicious); and (4) apple pulp sucrose concentrations were higher for Golden Delicious (17.5 μg mg^?1) than for either Granny Smith (15.9 μg mg^?1) or Red Delicious (15.1 μg mg^?1) varieties, which correlates positively with entry and development data. We conclude that host fruit species and varietals within a species affect the entry rate of neonate codling moth larvae in no‐choice assays. We hypothesize that larval development is influenced by mean sucrose concentrations or other phytochemical differences associated with host fruit varieties.     

Oviposition and feeding preferences of a flower-feeding weevil,Coelocephalapion aculeatum, in relation to conspecific damage to its host-plant

The oviposition and feeding preferences ofCoelocephalapion aculeatum Fall (Coleoptera: Apionidae), a host specific florivore ofMimosa pigra L. (Mimosaceae), were studied in relation to conspecific damage to its hostplant. Adults ofC. aculeatum cease ovipositing in inflorescences when the egg load reaches a number consistent with the larval carrying capacity of the inflorescence. The basis for this oviposition deterrence was examined by offering inflorescences damaged by adult feeding alone, larval feeding alone and a combination of adult feeding and oviposition. Adults preferred to oviposit on inflorescences which are not damaged by either adult feeding, larval feeding, or oviposition. No evidence for the existence of an oviposition deterring pheromone (ODP) was found. I suggest that the ability of a single host inflorescence to support the development of many larvae causes selection for the use of these oviposition deterring cues which can convey more quantitative information about the level of previous infestation than can ODPs. Adults fed a similar amount on damaged compared to undamaged inflorescences. These results assisted in the design of host range testing trials and allows predictions to be made about the effectiveness of this insect as a biological control agent.     

Environmental interactions with the toxicity of plant essential oils to the poultry red mite Dermanyssus gallinae

The toxicity of a range of plant essential oils to the poultry red mite, Dermanyssus gallinae (De Geer) (Acari: Dermanyssidae), a serious ectoparasitic pest of laying hens throughout Europe and elsewhere, was assessed in the laboratory. Dermanyssus gallinae may cause losses in egg production, anaemia and, in extreme cases, death of hens. With changes in legislation and consumer demand, alternatives to synthetic acaricides are needed to manage this pest. Fifty plant essential oils were selected for their toxicity to arthropods reported in the literature. Twenty-four of these essential oils were found to kill > 75% of adult D. gallinae in contact toxicity tests over a 24-h period at a rate of 0.21 mg/cm². Subsequent testing at lower rates showed that the essential oils of cade, manuka and thyme were especially toxic to adult D. gallinae . The toxicity of the seven most acaricidal essential oils was found to be stable at different temperatures likely to be encountered in commercial poultry housing (15°C, 22°C and 29°C), although results suggest that humidity and dust might influence the toxicity of some of the oils tested. The toxicity of clove bud essential oil to D. gallinae , for example, was increased at high humidity and dust levels compared with ambient levels. The results suggest that certain essential oils may make effective botanical pesticides for use against D. gallinae , although it is likely that issues relating to the consistency of the toxic effect of some oils will determine which oils will be most effective in practice.     

Flight and Oviposition Behavior of <Emphasis Type="BoldItalic">Ephestia cautella</Emphasis> and <Emphasis Type="Italic">Plodia interpunctella</Emphasis> in Response to Odors of Different Chocolate Products

The present study is included in a project with the aim to develop attractants from food odors for trapping female moths. Males and mated, but not unmated, females of Ephestia cautella and Plodia interpunctella were attracted by odors of three different chocolate products in flight tunnel experiments. Chocolate containing nut or rum elicited upwind flight and landing responses. Extracts of the chocolate products induced upwind flight in both species and both sexes. Larvae of the tested species survived best in plain chocolate (E. cautella) or nut-containing chocolate (P. interpunctella). The oviposition preference of P. interpunctella females seems to be highly adaptive, since females oviposited in the diet most suitable for larval feeding, whereas E. cautella females showed a less selective oviposition preference, between the diets tested.     

Toxicity of Artemisia annua (Asteraceae) essential oil on the tea mealy bug,Pseudococcus viburni Sigornet (Hemiptera: Pseudococcidae)

A combination of bioassay and biochemical approaches were used to determine toxicity of Artemisia annua essential oil (AaEO) Pseudococcus viburni. AaEO via leaf dipping bioassay showed LC₅₀ values of 0.693 and 0.419% after two time exposures. Different concentrations of AaEO caused deterrence index between 28.58 to 86.26% by the calculated ED₅₀ of 0.4%. Although, α-esterase activity using α-naphtyl acetate increased in the treated nymphs by AaEO after 24 hours but it showed the lower activity in the treated nymphs using β-naphtyl acetate. Glutathione S-transferase assayed by CDNB showed the higher activity in the treated nymphs than control after 24 hours while the adverse results gained not only after 48 hours but also after 24 hours by using DCNB. No significant differences were found in the activity of alanine aminotransferase versus control, but aspartate aminotransferase and γ-glutamyl transferase showed the statistically higher activities in the treated nymphs in comparison with control. Activities of aldolase and lactate dehydrogenase were significantly lower than those of control. Only acid phosphatase showed the significantly altered activity in the treated nymphs in comparison with control after 24 hours. Results of our study indicated significant toxicity, deterrence and physiological effects of AaEO on P. viburni.