Publications by authors named "Khrimian A"

The small black stem bug, Paratibraca (= Glyphepomis) spinosa (Campos and Grazia 1998), is a rice pest in Brazil and is part of a complex of stink bugs that includes Oebalus poecilus (Dallas) and Tibraca limbativentris Stål. Together, these pentatomid species pose a serious threat to rice crops throughout South America. In this study, we identified the sex pheromone of P.

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We found that vittatalactone, specifically (3R,4R)-3-methyl-4-[(1S,3S,5S)-1,3,5,7-tetramethyloctyl]oxetan-2-one, is the male-produced aggregation pheromone of the western striped cucumber beetle, Acalymma trivittatum (Mannerheim), as was previously shown for the striped cucumber beetle, Acalymma vittatum (F.) (Coleoptera: Chrysomelidae). A synthetic mixture containing 9% of the authentic natural pheromone, is attractive to both sexes of both species in the field, as demonstrated by trapping using baited and unbaited sticky panels in California and earlier in Maryland.

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Insects use diverse arrays of small molecules such as metabolites of the large class of terpenes for intra- and inter-specific communication and defense. These molecules are synthesized by specialized metabolic pathways; however, the origin of enzymes involved in terpene biosynthesis and their evolution in insect genomes is still poorly understood. We addressed this question by investigating the evolution of isoprenyl diphosphate synthase (IDS)-like genes with terpene synthase (TPS) function in the family of stink bugs (Pentatomidae) within the large order of piercing-sucking Hemipteran insects.

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Article Synopsis
  • * Research was conducted using synthetic pheromones and plant-derived chemicals (like allyl isothiocyanate) in various states to evaluate their effectiveness in attracting different flea beetle species.
  • * Findings revealed variable attraction responses among Phyllotreta species to these substances, indicating potential for improved pest monitoring and management, though further studies are needed for optimal solutions.
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The rice stalk stink bug, Tibraca limbativentris Stål, is an important rice pest in Brazil, causing significant damage to rice plants and consequently yield losses, with a high invasive potential in Mexico and USA. The male-produced sex pheromone of this species was recently identified as a 7:3 mixture of (3S,6S,7R)-1,10-bisaboladien-3-ol (1) and (3R,6S,7R)-1,10-bisaboladien-3-ol (5) (a.k.

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Sesquipiperitol is a sesquiterpene alcohol, some stereoisomers of which were found in several plant species. The biological role of these compounds in plants and their absolute configurations have not been reported. Recently, we found that 1,6,7 stereoisomer of sesquipiperitol was a key precursor in the biosynthesis of the harlequin bug, , pheromone, which consists of two stereoisomeric zingiberenol oxides.

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The rice stalk stink bug, Tibraca limbativentris, is an important rice pest in Brazil with a high invasive potential for Mexico and the USA. The sex pheromone of this species was previously identified as a combination of two stereoisomers of 1,10-bisaboladien-3-ol (zingiberenol), but the absolute configurations of these sesquiterpenes were not determined, neither were their effect(s) on T. limbativentris behavior evaluated.

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The brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae) is attracted to its male-produced aggregation pheromone, a ~3.5:1 mixture of (3S,6S,7R,10S)- and (3R,6S,7R,10S)-10,11-epoxy-1-bisabolen-3-ol (SSRS and RSRS respectively), and also to the pheromone of its Asian sympatric species Plautia stali Scott (Hemiptera: Pentatomidae), methyl (2E,4E,6Z)-2,4,6-decatrienoate (MDT). A stereoisomeric mixture of (7R) 10,11-epoxy-1-bisabolen-3-ols (= mixed murgantiols) is used together in commercialized products with MDT because the latter is a synergist for H.

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The original version of this article unfortunately contained a mistake. Under the heading "Insects" in "Methods and Materials" the sentence "A colony of N. viridula originated with field collections near Tifton, Georgia, USA" is incorrect.

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Insects use a wide range of structurally diverse pheromones for intra-specific communication. Compounds in the class of terpenes are emitted as sex, aggregation, alarm, or trail pheromones. Despite the common occurrence of terpene pheromones in different insect lineages, their origin from dietary host plant precursors or de novo biosynthetic pathways often remains unknown.

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Insects use a diverse array of specialized terpene metabolites as pheromones in intraspecific interactions. In contrast to plants and microbes, which employ enzymes called terpene synthases (TPSs) to synthesize terpene metabolites, limited information from few species is available about the enzymatic mechanisms underlying terpene pheromone biosynthesis in insects. Several stink bugs (Hemiptera: Pentatomidae), among them severe agricultural pests, release 15-carbon sesquiterpenes with a bisabolene skeleton as sex or aggregation pheromones.

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Background: Introduction of Halyomorpha halys (Stål) in the USA has disrupted many established integrated pest management programs for specialty crops, especially apple. While current management heavily relies on insecticides, one potential alternative tactic is attract-and-kill (AK), whereby large numbers of H. halys are attracted to and retained in a circumscribed area using attractive semiochemicals and removed from the foraging population with an insecticide.

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The brown marmorated stink bug, Halyomorpha halys, is an agricultural and urban pest that has become widely established as an invasive species of major concern in the USA and across Europe. This species forms large aggregations when entering diapause, and it is often these aggregations that are found by officials conducting inspections of internationally shipped freight. Identifying the presence of diapausing aggregations of H.

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The invasive stink bug species, Halyomorpha halys (Stål) (Hemiptera; Pentatomidae), severely damages multiple agricultural commodities, resulting in the disruption of established IPM programs. Several semiochemicals have been identified to attract H. halys to traps and monitor their presence, abundance, and seasonal activity.

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Two stereoisomeric zingiberenols in ginger were identified as (3R,6R,7S)-1,10-bisaboladien-3-ol (2) and (3S,6R,7S)-1,10-bisaboladien-3-ol (5). Absolute configurations were assigned by utilizing 1,10-bisaboladien-3-ol stereoisomers and two gas-chromatography columns: a 25 m Hydrodex-β-6TBDM and 60 m DB-5MS. The C-6 and C-7 absolute configurations in both zingiberenols match those of zingiberene present abundantly in ginger rhizomes.

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Euschistus servus (Say), Nezara viridula (L.), and Chinavia hilaris (Say) (Hemiptera: Pentatomidae) are economic pests of cotton in the coastal plain of the southeastern United States. The objective of this 2-yr study was to determine the ability of trap cropping systems, pheromone-baited stink bug traps, and a synthetic physical barrier at the peanut-to-cotton interface to manage stink bugs in cotton.

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A recent identification of the two-component aggregation pheromone of the invasive stink bug species, Halyomorpha halys (Stål), in association with a synergist, has greatly improved the ability to accurately monitor the seasonal abundance and distribution of this destructive pest. We evaluated the attraction of H. halys to black pyramid traps baited with lures containing the pheromone alone, the synergist methyl (2E,4E,6Z)-decatrienoate (MDT) alone, and the two lures in combination.

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The brown marmorated stink bug, Halyomorpha halys, is an invasive insect in the United States that is capable of inflicting significant yield losses for fruit, vegetable, and soybean growers. Recently, a male-produced aggregation pheromone of H. halys was identified as a 3.

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Preparation of a complete stereoisomeric library of 1,10-bisaboladien-3-ols and selected 10,11-epoxy-1-bisabolen-3-ols was pivotal for the identification of the aggregation pheromone of the brown marmorated stink bug, Halyomorpha halys. Herein, we describe syntheses of the remaining 10,11-epoxy-1-bisabolen-3-ols, and provide additional evidence on the assignment of relative and absolute configurations of these compounds by single-crystal X-ray crystallography of an intermediate, (3S,6R,7R,10S)-1-bisabolen-3,10,11-triol. To demonstrate the utility of this stereoisomeric library, we revisited the aggregation pheromone of the harlequin bug, Murgantia histrionica, and showed that the male-produced pheromone consists of two stereoisomers of 10,11-epoxy-1-bisabolen-3-ol.

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A two-component pheromone, (3S,6S,7R,10S)- and (3S,6S,7R,10R)-10,11-epoxy-1-bisabolen-3-ol (murgantiol), present in emissions from adult male harlequin bugs, Murgantia histrionica, is most attractive in field bioassays to adults and nymphs in the naturally occurring ratio of ca. 1.4:1.

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The reported male-produced aggregation pheromone of the brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), identified as a mixture of (3S,6S,7R,10S)-10,11-epoxy-1-bisabolen-3-ol and (3R, 6S, 7R, 10S)-10,11-epoxy-1-bisabolen-3-ol, offers new opportunities for its management. We found that black pyramid traps deployed along crop borders in Maryland and West Virginia, containing lures with both stereoisomers of this reported aggregation pheromone combined with methyl (E,E,Z)-2,4,6-decatrienoate (MDT) lures, attracted more adult and nymphal H. halys than either the aggregation pheromone or MDT alone.

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We describe a novel and straightforward route to all stereoisomers of 1,10-bisaboladien-3-ol and 10,11-epoxy-1-bisabolen-3-ol via the rhodium-catalyzed asymmetric addition of trimethylaluminum to diastereomeric mixtures of cyclohex-2-enones 1 and 2. The detailed stereoisomeric structures of many natural sesquiterpenes with the bisabolane skeleton were previously unknown because of the absence of stereoselective syntheses of individual stereoisomers. Several of the bisabolenols are pheromones of economically important pentatomid bug species.

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Attraction of emerald ash borer, Agrilus planipennis Fairmaire, to a volatile pheromone was demonstrated in three field experiments using baited green sticky traps. A dose-response curve was generated for male A. planipennis to increasing release rates of (3Z)-dodecen-12-olide ((3Z)-lactone) in combination with the green leaf volatile, (3Z)-hexenol.

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Field trapping assays were conducted in 2009 and 2010 throughout western Michigan, to evaluate lures for adult emerald ash borer, A. planipennis Fairmaire (Coleoptera: Buprestidae). Several ash tree volatiles were tested on purple prism traps in 2009, and a dark green prism trap in 2010.

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An unsaturated hydroxy-ester pheromone was isolated from the headspace and feces of male Diaprepes abbreviatus, identified, and synthesized. The pheromone, methyl (E)-3-(2-hydroxyethyl)-4-methyl-2-pentenoate, was discovered by gas chromatography-coupled electroantennogram detection (GC-EAD), and identified by gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance spectroscopy (NMR). The synthesis yielded an 86:14 mixture of methyl (E)-3-(2-hydroxyethyl)-4-methyl-2-pentenoate (active) and methyl (Z)-3-(2-hydroxyethyl)-4-methyl-2-pentenoate (inactive), along with a lactone breakdown product.

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