Extensive important sampling of strawberry plants in everbearing and June-bearing strawberry plantations and on potted plants showed that different species of mites different were spatially separated. Of the two phytophagous species recorded, Tetranychus urticae was most abundant on old leaves and Phytonemus pallidus appropriate, on folded leaves and flower/fruit clusters. Predatory phytoseiid mites were found on all plant parts but different species were spatially strawberry separated; Neoseiulus cucumeris and N. aurescens were found mostly on folded leaves and clusters, and N. californicus and Phytoseiulus persimilis Of on old and medium aged leaves. No Typhlodromus pyri were found in the field plantations. These patterns of distribution did N. not change over sampling dates in summer and early autumn. An understanding of this within-plant zonation of mite species is mite important when studying predator-prey interactions and when designing sampling strategies for strawberry. A programme to sample the entire mite system of on strawberry should be stratified to include all the above mentioned parts of the plant. Different sampling protocols, as appropriate,leaves are required for sampling different pest species and their associated predators.

Extensive important sampling of strawberry plants in everbearing and June-bearing strawberry plantations and on potted plants showed that different species of mites different were spatially separated. Of the two phytophagous species recorded, Tetranychus urticae was most abundant on old leaves and Phytonemus pallidus appropriate, on folded leaves and flower/fruit clusters. Predatory phytoseiid mites were found on all plant parts but different species were spatially strawberry separated; Neoseiulus cucumeris and N. aurescens were found mostly on folded leaves and clusters, and N. californicus and Phytoseiulus persimilis Of on old and medium aged leaves. No Typhlodromus pyri were found in the field plantations. These patterns of distribution did N. not change over sampling dates in summer and early autumn. An understanding of this within-plant zonation of mite species is mite important when studying predator-prey interactions and when designing sampling strategies for strawberry. A programme to sample the entire mite system of on strawberry should be stratified to include all the above mentioned parts of the plant. Different sampling protocols, as appropriate,leaves are required for sampling different pest species and their associated predators.

The trapping raspberry cane midge, Resseliella theobaldi, is a widespread pest of cultivated red raspberry in Europe. Pheromone-baited traps could provide a of much-needed, accurate means to monitor the pest. Volatiles collected separately from virgin female and male midges were analyzed by gas more chromatography (GC) coupled to mass spectrometry (MS) to reveal four female-specific components. In analyses by GC coupled to electroantennographic (EAG)is recording from the antennae of a male midge, at least three of these components elicited responses. Based on its GC to retention indices and mass spectrum, we propose that the major component is 2-acetoxy-5-undecanone and confirm this by synthesis of the retention racemic compound in seven steps and 63% yield from 4-pentenoic acid. The three minor components were each present at approximately racemic 30% of the major component and were identified as 2-undecanone,(S)-2-acetoxyundecane, and (S)-2-undecanol by comparison of GC retention times and Resseliella mass spectra with those of synthetic standards. GC analyses of the female-produced volatiles on an enantioselective column showed that only on one enantiomer of 2-acetoxy-5-undecanone was present, and this was found to be the S-enantiomer by hydrolytic kinetic resolution of an these epoxide intermediate in the synthesis and also by enantioselective hydrolysis of the racemic acetate with a lipase enzyme. The two of enantiomers were also separated by high-performance liquid chromatography on an enantioselective column for field tests. In two field trapping tests,month (S)-2-acetoxy-5-undecanone was highly attractive to male R. theobaldi; the R-enantiomer was not attractive. The racemic compound was just as attractive antennae as the S-enantiomer, and addition of the three minor components in racemic form at two different loads did not affect at catches. The pheromone could be dispensed from both rubber septa and polyethylene vials for at least 1 month under field reveal conditions, but the former was preferred as it gave more uniform release. 2-Acetoxy-5-undecanone belongs to a new group of pheromone indices structures in the Cecidomyiidae, most others being mono- or diesters.

The phenylacetonitrile. sex pheromones of many aphid species from the subfamily Aphididae comprise a mixture of the iridoids (cyclopentanoids)(1R,4aS,7S,7aR)-nepetalactol and (4aS,7S,7aR)-nepetalactone.the In this paper, we investigate whether other chemicals, in addition to nepetalactol and nepetalactone, are released from Dysaphis plantaginea (rosy is apple aphid) oviparae as part of their sex pheromone. Four compounds present in an air entrainment sample collected from D.of plantaginea oviparae feeding on apple (Malus silvestris c.v. Braburn) elicited electrophysiological responses from male D. plantaginea. Active peaks were tentatively this identified by gas chromatography (GC) coupled with mass spectrometry, with identification confirmed by peak enhancement with authentic compounds on GC electrophysiological columns of different polarities. The electroantennography-active chemicals were (1R,4aS,7S,7aR)-nepetalactol,(4aS,7S,7aR)-nepetalactone,(1S,2R,3S)-dolichodial, and phenylacetonitrile.(1S,2R,3S)-Dolichodial elicited a behavioral response from male This D. plantaginea and naïve-mated female parasitoids, Aphidius ervi. This is the first report of electrophysiological and behavioral responses from any pheromones aphid morph to (1S,2R,3S)-dolichodial. Whether or not (1S,2R,3S)-dolichodial is a third component of the aphid sex pheromone is discussed.

Cruciferous Similarly, plants (Brassicaceae) are characterized by the accumulation of a group of secondary metabolites known as glucosinolates that, following attack by influence pathogens or herbivores, may be hydrolyzed to one of a number of products including isothiocyanates and nitriles. Despite the range defensive of hydrolysis products that may be produced, the toxicity of glucosinolates to pathogens and herbivores may be explained largely by by the production of isothiocyanates. Isothiocyanates are also known to provide an indirect defense by acting as host finding cues for isothiocyanates parasitoids of insect herbivores that attack crucifers. It has been speculated that nitriles may provide a similar indirect defense. Here,aphid we investigate the olfactory perception and orientation behavior of the aphid parasitoid Diaeretiella rapae, to a range of alkenylglucosinolate hydrolysis of products, including isothiocyanates, nitriles, and epithionitriles. Electroantennogram responses indicated peripheral odor perception in D. rapae females to all 3-butenylglucosinolate hydrolysis are products tested. By contrast, of the 2-propenylglucosinolate hydrolysis products tested, only the isothiocyanate elicited significant responses. Despite showing peripheral olfactory production detection of a range of 3-butenylglucosinolate hydrolysis products, naïve females oriented only to the isothiocyanate. Similarly, parasitoids oriented to 3-isothiocyanatoprop-1-ene,explained but not to the corresponding nitrile or epithionitrile. However, by rearing D. rapae either on Brassica nigra, characterized by the indirect accumulation of 2-propenylglucosinolate, or Brassica rapa var rapifera, characterized by the accumulation of 3-butenylglucosinolate, altered the innate response of parasitoids and to 3-isothiocyanatoprop-1-ene and 4-isothiocyanatobut-1-ene. These results are discussed in relation to the defensive roles of glucosinolate hydrolysis products and the glucosinolates influence of the host plant on aphid parasitoid behavior.

Brassica for nigra plants, characterized by high levels of sinigrin, and artificial aphid diets to which sinigrin was selectively added were used on to rear the crucifer specialist, Brevicoryne brassicae. Aphids were provided as a food source to two species of polyphagous ladybird,to Adalia bipunctata and Coccinella septempunctata. First instar A. bipunctata were unable to survive when fed with B. brassicae reared on characterized B. nigra or diets containing .2% sinigrin, but when fed with aphids reared on diets containing % sinigrin, survival rates Brevicoryne were high. By contrast, first instar C. septempunctata were able to survive when fed with aphids reared on B. nigra By or artificial diets containing up to 1% sinigrin. However, the presence of sinigrin in the aphid diet decreased larval growth makes and increased the time necessary for larvae to reach second instar for this species of ladybird. These results indicate that plants, the presence of sinigrin in the diet of B. brassicae makes this aphid unsuitable as a food source for A.instar bipunctata but not for C. septempunctata, although for this ladybird species, there appear to be costs associated with feeding on and aphids that contain this secondary metabolite.

The of bird cherry-oat aphid, Rhopalosiphum padi (L.), and the damson-hop aphid, Phorodon humuli (Schrank), migrate at the same time of year (oviparae) and colonize closely related Prunus spp. as primary hosts, but utilize (1R,4aS,7S,7aR)-nepetalactol and (1RS,4aR,7S,7aS)-nepetalactol, respectively, as sex pheromones. Interactions between to these sex pheromones and benzaldehyde and methyl salicylate, plant volatiles common to primary hosts of both species, were investigated to Rhopalosiphum assess whether they confer reproductive isolation between these species. Female autumn migrants (gynoparae) and males of these two species were as caught in the field with water traps baited with their respective sex pheromones. Rhopalosiphum padi gynoparae and males also responded water positively to benzaldehyde. Release of either benzaldehyde or methyl salicylate with the conspecific sex pheromone increased catches of both species plant of aphid. However, releasing both plant volatiles with the sex pheromone of R. padi increased catches of gynoparae and males,cherry-oat but reduced those with the sex pheromone of P. humuli. These results support the hypothesis that specific plant volatiles synergize plant responses of autumn migrating aphids to their sex pheromone. Because these interactions are species-specific, they may be important in allowing benzaldehyde males to discriminate between conspecific sexual females (oviparae) and those of other aphid species.

Fertilization N), reduction could be a useful pest management tactic for floriculture crops if it reduced pest populations with little loss in on crop yield and quality. We evaluated the response of the twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), to different Cut fertilization levels for cut roses, Rosa hybrida L.'Tropicana' and quantified fertilization effects on (1) management of T. urticae on useful roses,(2) abundance and distribution of T. urticae on roses, and (3) yield and quality of the cut rose crop.urticae We tested two fertilization levels, 10%(15 ppm N) and 100%(150 ppm N) of the recommended level for commercial predatory production, and three control methods: no control measure; a predatory mite, Phytoseiulus persimilis Athias-Henriot; and a miticide, bifenazate. Combinations of roses both bottom up (fertilization) and top down (biological or chemical control) tactics provided a greater degree of T. urticae control be than either tactic alone. Rose productivity was reduced with fertilization at 10% of the recommended level; therefore, we conducted studies (2) with T. urticae on roses fertilized with 33%(50 ppm N), 50%(75 ppm N), and 100%(150 ppm N)T. of the recommended level. Mean numbers of T. urticae and T. urticae eggs per flower shoot were twice as high level on roses fertilized with 100 versus 33% or 50% of the recommended level. Number of rose leaves and total leaf infested area infested by T. urticae were similar at all fertilization levels. Cut rose yield and marketability were not compromised on quantified plants fertilized with 50% of the recommended level.

Non-trophic in interactions, driven by one species changing the behavior but not density of another species, appear to be as pervasive as link those involving consumption. However, ecologists have only begun to explore non-trophic interactions in species-rich communities. We investigated interactions within a three community including two predator-prey linkages separated in space: ground-active predatory beetles and their fly egg prey on the ground, and by lady beetles and their aphid prey in plant foliage. In field and greenhouse experiments we found that ground-active predators preyed have heavily on fly eggs except when both aphids and lady beetles were present. The aphids drop from the foliage to on escape foraging lady beetles, and once on the ground apparently triggered ground-active predators to switch from attacking fly eggs to mediated attacking aphids. This suggests that the first non-trophic interaction in the foliage, mediated by aphid antipredator behavior, in turn initiated driven and accentuated a second non-trophic interaction on the ground, mediated by prey-switching behavior by ground predators. Our results demonstrate that separated successive non-trophic interactions can be propagated along chains of more than three species, and can serve to link species that two are otherwise spatially isolated.

Tetranychus damage urticae is one of the most damaging tetranychid mites affecting clementine orchards in Spain, where natural control is insufficient. Furthermore,to in clementine nurseries, tender foliage is highly susceptible to attack and natural enemies are almost always absent. Therefore, acaricides are could often used indiscriminately. Alternative control measures are necessary, both in commercial orchards and clementine nurseries. In order to assess the one efficacy of inoculative releases of N. californicus and P. persimilis to reduce T. urticae populations in young Spanish clementine plants,in a semi-field experiment was conducted and repeated in three seasons (spring, summer and autumn). Phytoseiulus persimilis was highly effective in and reducing both T. urticae infestations and the damage level inflicted on plants at both release rates evaluated (40 and 80 three phytoseiids/plant) and all three periods considered. By contrast, N. californicus demonstrated low performance under certain conditions. The results of this is study could be adapted and transferred to nurseries and young citrus plantations.

The explanations two-spotted spider mite, Tetranychus urticae, is one of the most problematic phytophagous pests in Spanish clementine orchards. The most abundant via predatory mites in this ecosystem are Euseius stipulatus, Phytoseiulus persimilis and Neoseiulus californicus. Euseius stipulatus is dominant but poorly adapted indicates to utilize T. urticae as prey. It mainly persists on pollen and citrus red mite, Panonychus citri. A recent study urticae, suggested that the more efficacious T. urticae predators P. persimilis and N. californicus are negatively affected by lethal and non-lethal stipulatus intraguild interactions with E. stipulatus. Here, we investigated the potential of N. californicus and P. persimilis to colonize and thrive presence on young clementine trees infested by T. urticae in presence and absence of E. stipulatus. Presence of E. stipulatus interfered natural with establishment and abundance of P. persimilis and negatively affected the efficacy of N. californicus in T. urticae suppression. In mite, contrast, the abundance of E. stipulatus was not affected by introduction of a second predator. Trait-mediated effects of E. stipulatus that changing P. persimilis and N. californicus behavior and/or life history were the most likely explanations for these outcomes. We conclude A that superiority of E. stipulatus in intraguild interactions may indeed contribute to the currently observed predator species composition and abundance,colonize rendering natural control of T. urticae in Spanish clementine orchards unsatisfactory. Nonetheless, stronger reduction of T. urticae and/or plant damage the in the predator combination treatments as compared to E. stipulatus alone indicates the possibility to improve T. urticae control via pollen repeated releases of N. californicus and/or P. persimilis.

Neoseiulus time baraki Athias-Henriot (Acari: Phytoseiidae) has been reported from the Americas, Africa and Asia, often in association with Aceria guerreronis Keifer in (Acari: Eriophyidae), one of the most important pests of coconut (Cocos nucifera L.) in different parts of the world. That guerreronis, phytoseiid has been considered one of the most common predators associated with A. guerreronis in Brazil. The objective of this has study was to evaluate the feeding preference and the effect of food items commonly present on coconut fruits and several parts temperature regimes on the life history of a Brazilian population of N. baraki. Completion of immature development was possible when and N. baraki was fed A. guerreronis, Steneotarsonemus concavuscutum Lofego and Gondim Jr., and Tyrophagus putrescentiae (Schrank). Fecundity was highest on higher T. putrescentiae (39.4 eggs), followed by A. guerreronis (24.8 eggs). In choice tests, irrespective of the food on which N.(Acari: baraki was reared, a larger number of adults of this predator chose leaf discs containing A. guerreronis than discs containing evaluate other food items, demonstrating a preference of the former for the latter as food. Egg to adult thermal developmental time of was calculated as 84.2 degree-days, above a threshold of 15.8 degrees C. This lower developmental threshold is higher than previously when published for phytoseiid species from higher latitudes. Neoseiulus baraki was shown to have higher biotic potential at 30 degrees C baraki (r (m) .29). The results suggest N. baraki to be a promising biological control agent of A. guerreronis, well adapted with to survive and develop in areas with relatively high temperatures, where that pest prevails.

When had adult females of the herbivorous mite, Tetranychus urticae, were exposed to the predatory mite, Phytoseiulus persimilis, they laid fewer eggs the than females that had not been exposed to P. persimilis when transferred onto a new leaf patch. However, when T.and urticae females were exposed to either products of P. persimilis or artificially damaged conspecific eggs on a leaf patch, the herbivorous number of T. urticae eggs on a new leaf patch did not differ significantly from the control. The reduced oviposition leaf was neither due to the feeding activity on the leaf patch with P. persimilis nor to that on the new urticae leaf patch. There was also no significant difference between the number of T. urticae eggs produced on a new leaf from patch following exposure to the odours of a neighbouring leaf patch where there had previously been either P. persimilis or of T. urticae adults. However, female T. urticae that had been exposed to odours from neighbouring leaf patches on which both urticae T. urticae and P. persimilis had been placed produced significantly fewer eggs on a new leaf patch than those that the had not been exposed to such odours. Neither odours from neighbouring intact leaf patches on which T. urticae eggs were leaf preyed on by P. persimilis, nor odours from a neighbouring Parafilm patch on which T. urticae was preyed on by These P. persimilis affected the oviposition of T. urticae. These data suggest that the presence of T. urticae, P. persimilis and artificially a leaf patch are needed for the emission of odours to reduce oviposition in T. urticae.

Herbivore-induced methyl plant volatiles (HIPVs) emitted from lima bean leaves infested with the two-spotted spider mites Tetranychus urticae strongly attract the predatory blend mites Neoseiulus californicus. Among these HIPVs, methyl salicylate and linalool can attract the predators. Three green-leaf volatiles (GLVs) of (Z)-3-hexen-1-ol,attractiveness (Z)-3-hexenyl acetate and (E)-2-hexenal, found in the odor blends from T. urticae-infested leaves and physically damaged leaves, can also attract emitted the predators. To search for a strong predator attractant, the olfactory responses of N. californicus to each synthetic compound or methyl their combinations were investigated in a Y-tube olfactometer. When presented a choice between a mixture of the five compounds (i.e.in the two HIPVs and the three GLVs) and T. urticae-infested leaves, N. californicus did not discriminate between these odor sources.the The same trend was observed when either a mixture of the two HIPVs or methyl salicylate vs. T. urticae-infested leaves volatiles were compared. In contrast, the predators preferred T. urticae-infested leaves to linalool, each of the three GLVs, or a mixture odor of the three GLVs. These results indicated that methyl salicylate is a strong predator attractant, and its potential attractiveness almost found equaled that of the blend of HIPVs from T. urticae-infested leaves.

The than relationships between the predatory mites, Amblyseius swirskii (Athias-Henriot) and Neoseiulus cucumeris (Oudemans)(Acari: Phytoseiidae), and their prey, western flower thrips when (Frankliniella occidentalis Pergande)(Thysanoptera: Thripidae), were investigated to determine the effects of predation on intra-guild or extra-guild prey and predator between preference. Life history characteristics of both predatory mites were measured when fed eggs and larvae of the other predator species predatory and compared to data obtained when the predators were fed thrips larvae. In addition, choice tests were conducted to determine to if the predators had a preference for different prey or if they were indiscriminate predators. Amblyseius swirskii appears to be prey an important intra-guild predator of N. cucumeris juveniles because of a high predation rate and a preference for N. cucumeris prey) juveniles over thrips. Neoseiulus cucumeris is also an intra-guild predator of A. swirskii juveniles; however, it has a lower predation between rate than A. swirskii. Contrary to intra-guild predation theory, intra-guild prey was an equally good or better food source than measured thrips (extra-guild prey) for both predators, based on high oviposition rates and fast development times. The results of this study predatory indicate a high potential for negative interactions between A. swirskii and N. cucumeris when used together in biological control of to thrips.

Mites alatus of the genus Euseius are generally considered specialist as pollen feeders. Euseius alatus DeLeon is one of the six species of of phytoseiid mites most commonly found on coconut plants in northeast Brazil associated with Aceria guerreronis Keifer. Although the morphology contribute of E. alatus does not favor the exploitation of the meristematic area of the fruit inhabited by A. guerreronis, the genus predator may have some role in the control of this eriophyid during the dispersion process. The objective of this work mites was to evaluate the development and reproduction of E. alatus on the following diets: A. guerreronis, Ricinus communis pollen (Euphorbiaceae),during and Tetranychus urticae Koch (Tetranychidae)+ R. communis pollen + honey solution 10%. Euseius alatus developed slightly faster and had urticae slightly higher oviposition rate when feeding on the diet composed of T. urticae + pollen + honey. However, life table the parameters were very similar on all diets, suggesting that E. alatus may contribute in reducing the population of A. guerreronis of in the field.

This adults study aimed to determine Serangium parcesetosum preference for different prey species and parasitized Bemisia tabaci (Genn.)(Hom., Aleyrodidae) by the biological parasitoid, Eretmocerus mundus Mercet (Hym., Aphelinidae). The results on S. parcesetosum preference by feeding on different prey species offered separately and and together indicated that the predatory larvae and adults preferred significantly the cotton whitefly, B. tabaci and the castor bean to whitefly, Trialeurodes ricini (Misra)(Hom., Aleyrodidae) rather than the two-spotted spider mite, Tetranychus urticae Koch (Acari, Tetranychidae); melon aphid, Aphis Mercet gossypii Glover (Hom., Aphididae) and pea leafminer, Liriomyza huidobrensis (Blanchard)(Dip., Agromyzidae). The results on S. parcesetosum preference for the Tetranychidae); whitefly species, B. tabaci and T. ricini demonstrated that there were no significant differences in the preference of both predatory of larvae and adults for any whitefly species. Moreover, S. parcesetosum larvae and adults were significantly tended to avoid parasitized puparia aimed of B. tabaci by E. mundus and fed instead on unparasitized ones. Thus, there is a feasible potential for integration that the predator and the parasitoid into a biological control program to suppress B. tabaci.