Seasonal patterns of beneficial phytochemical availability in honey and stored pollen from honey bee colonies in large apiaries.

Honey bees (Apis mellifera L.; Hymenoptera, Apidae) are the most efficient pollinators in agroecosystems, responsible for the successful production of fruits, nuts, and vegetables, but they continue to face debilitating challenges. One of the major factors leading to these challenges could be linked to poor nutrition that results in weakening the colony, increasing susceptibility to pests and pathogens, and reducing the ability of bees to adapt to other abiotic stresses.

Context-Dependent Effect of Dietary Phytochemicals on Honey Bees Exposed to a Pesticide, Thiamethoxam.

Honey bees continue to face challenges relating to the degradation of natural flowering habitats that limit their access to diverse floral resources. While it is known that nectar and pollen provide macronutrients, flowers also contain secondary metabolites (phytochemicals) that impart benefits including increased longevity, improved gut microbiome abundance, and pathogen tolerance. Our study aims to understand the role of phytochemicals in pesticide tolerance when worker bees were fed with sublethal doses (1 ppb and 10 ppb) of thiamethoxam (TMX), a neonicotinoid, in 20% (w/v) sugar solution supplemented with 25 ppm of phytochemicals-caffeine, kaempferol, gallic acid, or p-coumaric acid, previously shown to have beneficial impacts on bee health.

Characterization of Corn Root Factors to Improve Artificial Diet for Western Corn Rootworm (Coleoptera: Chrysomelidae) Larvae.

The western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), is an important economic pest of maize (Zea mays L.) in North America and Europe. Previous efforts to formulate an artificial diet for western corn rootworm larvae highlighted an important role of corn root powder, which had a significant positive impact on several larval developmental traits.

Metabolomic analysis of pollen from honey bee hives and from canola flowers.

Background And Aims: Pollen is essential for successful plant reproduction and critical for plant-pollinator mutualisms, as pollen is essential larval nutrition. However, we understand very little about the chemical constituents of pollen leading us to this exploratory study characterizing plant and beehive pollen.

Methods: We performed a metabolomics assay of canola flower pollen and beehive pollen.

Comparative Susceptibility of Western Corn Rootworm (Coleoptera: Chrysomelidae) Neonates to Selected Insecticides and Bt Proteins in the Presence and Absence of Feeding Stimulants.

The susceptibility of western corn rootworm, Diabrotica virgifera virgifera LeConte, larvae to nine insecticides from five different classes and to Bt proteins eCry3.1Ab and mCry3A in the presence or absence of feeding stimulants, was estimated in filter paper and diet toxicity assays, respectively. The use of a synthetic feeding stimulant blend of the sugars glucose, sucrose, and fructose plus linoleic acid at a ratio of 30:4:4:0.

Dietary Phytochemicals, Honey Bee Longevity and Pathogen Tolerance.

Continued loss of natural habitats with native prairies and wildflower patches is eliminating diverse sources of pollen, nectar and phytochemicals therein for foraging bees. The longstanding plant-pollinator mutualism reiterates the role of phytochemicals in sustaining plant-pollinator relationship and promoting honey bee health. We studied the effects of four phytochemicals-caffeine, gallic acid, kaempferol and -coumaric acid, on survival and pathogen tolerance in the European honey bee, (L.

Repellent Effects of Methyl Anthranilate on Western Corn Rootworm Larvae (Coleoptera: Chrysomelidae) in Soil Bioassays.

Methyl anthranilate (MA), a compound in maize roots that is repellent to western corn rootworm larvae (Diabrotica virgifera virgifera LeConte) was tested in behavioral bioassays in a soil environment. MA prevented larvae from locating roots of a maize seedling, and the repellency strengthened with increasing rates of MA. In a simple push-pull strategy between an MA-treated seedling and an untreated seedling, granules containing 0.

Methyl Anthranilate as a Repellent for Western Corn Rootworm Larvae (Coleoptera: Chrysomelidae).

Methyl anthranilate was identified as the active compound in extracts of maize (Zea mays L.) roots that were shown to be repellent to neonate western corn rootworm (Diabrotica virgifera virgifera LeConte) larvae. A bioassay-driven approach was used to isolate the active material from diethyl ether extracts of roots from germinating maize seeds.

Monogalactosyldiacylglycerols as Host Recognition Cues for Western Corn Rootworm Larvae (Coleoptera: Chrysomelidae).

Monogalactosyldiacylglycerol (MGDG) was identified as a host recognition cue for larvae of the western corn rootworm Diabrotica virgifera virgifera LeConte. An active glycolipid fraction obtained from an extract of germinating maize roots was isolated with thin layer chromatography using a bioassay-driven approach. When analyzed with LC-MS (positive ion scanning), the assay-active spot was found to contain four different MGDG species: 18:3-18:3 (1,2-dilinolenoyl), 18:2-18:3 (1-linoleoyl, 2-linolenoyl), 18:2-18:2 (1,2-dilinoleoyl), and 18:2-16:0 (1-linoleoyl, 2-palmitoyl).

Isolation and characterization of host recognition cues in corn roots for larvae of the western corn rootworm (Coleoptera: Chrysomelidae).

Behavioral bioassays were used to isolate compounds from germinating corn roots that elicit a host recognition response (tight-turning behavior) by neonate larvae of the western corn rootworm Diabrotica virgifera virgifera LeConte. When a behaviorally active extract of germinating corn roots was separated into an aqueous partition and a hexane partition, significantly more larvae (P < 0.05) responded to the recombined partitions than to either partition alone, demonstrating that the active material is a blend comprising both polar and nonpolar compounds.

Antixenosis in maize reduces feeding by western corn rootworm larvae (Coleoptera: Chrysomelidae).

SUM2162 is the first known example of a naturally occurring maize, Zea mays L., genotype with antixenosis (nonpreference) resistance to western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), larval feeding. Behavioral responses of neonate western corn rootworm larvae were evaluated in laboratory bioassays with seven maize genotypes selected for native resistance to rootworm feeding damage.

Localized search cues in corn roots for western corn rootworm (Coleoptera: Chrysomelidae) larvae.

Cues that elicit a characteristic localized search behavior by neonate larvae of the western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), were extracted from living corn, Zea mays L., roots with acetone. Larvae were exposed to corn roots or to an acetone extract of corn roots and then transferred into a bioassay arena where their movements were tracked and recorded.

Identification of feeding stimulants in corn roots for western corn rootworm (Coleoptera: Chrysomelidae) larvae.

Using a bioassay-driven approach, we have isolated and identified a blend of compounds from the roots of germinating corn, Zea mays L., that serve as feeding stimulants for neonate western corn rootworm larvae, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae). The active blend is a combination of simple sugars (30:4:4 mg/ml glucose:fructose:sucrose in the corn root) plus at least one of the free fatty acids in germinating corn roots (2:5 mg/ml oleic acid:linoleic acid in the corn root).

Insecticide enhancement with feeding stimulants in corn for western corn rootworm larvae (Coleoptera: Chrysomelidae).

Amounts of the insecticide thiamethoxam required for 50% mortality of western corn rootworm larvae, Diabrotica virgifera virgifera LeConte, were reduced 100-fold when extracts of germinating corn, Zea mays L., were used to entice neonate larvae to feed on it. In behavioral bioassays, neonate rootworm larvae fed vigorously on filter paper disks treated with liquid pressed from corn roots.

Attraction of subterranean termites (Isoptera) to carbon dioxide.

Subterranean termites, Reticulitermes spp., were attracted to carbon dioxide (CO2) in laboratory and field tests. In behavioral bioassays, Reticulitermes flavipes (Kollar), Reticulitermes tibialis Banks, and Reticulitermes virginicus Banks were attracted to CO2 concentrations between 5 and 50 mmol/mol.

Disruption of host location of western corn rootworm larvae (Coleoptera: Chrysomelidae) with carbon dioxide.

Elevated concentrations of carbon dioxide (CO2) prevented neonate larvae of the western corn rootworm, Diabrotica virgifera virgifera LeConte, from locating the roots of growing corn in behavioral bioassays conducted in soil tubs. When CO2 was pumped into one end of a soil tub, significantly more larvae were recovered from soil at the treated end than from soil around a growing corn plant at the opposite end of the tub. In controls with ambient air pumped into one end of a soil tub, significantly more larvae were recovered from the soil around the corn plant than from soil on the treated side.

Long-chain free fatty acids: Semiochemicals for host location by western corn rootworm larvae.

A bioassay-driven sequential fractionation scheme was used to isolate fractions of a crude dichloromethane maize seedling extract behaviorally active to larvae of the western corn rootworm,Diabrotica virgifera virgifera LeConte. (Z,Z)-9,12-Octadecadienoic (linoleic) acid, (Z)-9-octadecenoic (oleic) acid, and octadecanoic (stearic) acid were identified from a purified fraction of maize extract that was attractive to western corn rootworm larvae in choice tests with equal levels of carbon dioxide on both sides of the choice. When synthetic linoleic, oleic, and stearic acids were tested together in the amounts and proportions found in the attractive fraction (1000, 800, and 300 ng of linoleic, oleic, and stearic acids, respectively), significantly more western corn rootworm larvae were found on the side with synthetic free fatty acids plus carbon dioxide than on the side with carbon dioxide alone.

[Is percutaneous liver biopsy using the Trucut (Travenol) needle superior to Menghini puncture?].

The aim of this study was to compare the quality of biopsy cylinders obtained by the Menghini or Trucut liver biopsy-method as well as the frequency of complications observed with both these methods. For this purpose, 74 Menghini and 62 Trucut biopsies were analyzed. Both groups were comparable with respect to histologic diagnosis, but no final diagnosis could be made in eight cases of Menghini biopsy because of insufficiency of the material obtained.