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Electroantennographic and single sensillum recordings were performed on male pine sawfly, Neodiprion sertifer, antennae. Responses to the sex pheromone component (2S, 3S, 7S)- 3,7-dimethyl-2-pentadecenyl (diprionyl) acetate (SSS:OAc), to the behavioral inhibitor (2S, 3R, 7R)-diprionyl acetate (SRR:OAc), to the six other enantiomers of diprionyl acetate, and to the biosynthetic precursor diprionol
Abstract. 1. The bole of a Norway spruce, Picea abies(L.) Karst., was cut in 25 cm sections and infested in the laboratory with 2 or 8 females/dm2 of Ips typographus (L.) and an equal number of males. 2. One log of each beetle density was dissected every second day, beginning 2 days after female introduction. 3. The oviposition rate was highest at the beginning of the breeding period for both den
The behavior of 118 spruce bark beetles, Ips typographus, was observed on trees under colonization. Most individuals were followed from when they landed until they entered or left the tree. Both males and females spent most time inspecting crevices and searching for a place to start boring or for a hole to enter. These behaviors accounted for 87 and 70% of all behavioral acts recorded for males an
A summary of the present knowledge of variation in individual quality within a bark beetle population is given, with emphasis on the spruce bark beetle Ips typogrophus, A major causal factor is density, mediated by competition during larval development. Density negatively influences individual quality measured as weight, fat content and pheromone production. Together with decreasing mean values at
A model of attack dynamics on a single tree under mass attack by the spruce bark beetle Ips typographus is developed from earlier studies of pheromone production and response of the flying population to the pheromone signal. The model is explored for different numbers and sex‐ratios of pioneer beetles and responding beetles. Both numbers of pioneers and responders were important for the dynamics,
In studying the attraction of spruce bark beetles Ips typographus to a pheromone trap, we have proposed a simple diffusion model with drift as a description of the flight of the bark beetles. The model predictions were compared with the results of a release‐recapture experiment, and here we recapitulate the main results from the fitting of models to the data. Several modifications of the basic mod
Two novel easy‐to‐make pheromone traps, a cross‐barrier sticky trap and an open horizontal sticky trap, are described. Both types caught about the same number of male pine sawflies, Neodiprion sertifer, when baited with the synthetic pheromone (2S, 3S, 7S)‐3,7‐dimethylpentadec‐2‐yl acetate. The catch on unbaited cross‐barrier traps was about 17% compared with baited traps, whereas unbaited horizon
ABSTRACT. This study investigated a possible trade‐off between bark beetle reproductive effort and future survival. Parent adult Ips typographus (L.) (Coleoptera: Scolytidae) were collected when they re‐emerged from a laboratory culture after completing their first brood and held at constant temperatures of 4 or 25oC. As a comparison, emerging brood adults were collected and held at 25oC. The lon
The biological role of non-symbiotic plant hemoglobins (Hbs) is not well understood. It may involve sensing and signaling of reactive nitrogen and oxygen species–a property that can be used in electrochemical sensing. Here, we electrochemically studied two novel non-symbiotic Beta vulgaris Hbs: BvHb1.2 and BvHb2 expressed in E. coli. At pH 7, we observed close potentials of their Fe2+/3+ hemes, −3
In 2016, archaeological excavations undertaken by the Ephorate of Antiquities of West Attica, Piraeus and Islands 3.8 km south-west of Athens, Greece, revealed mass burials of 79 skeletons in three rows. The burials are dated to the 7th century BC. The anthropological field documentation was undertaken by The Swedish Institute of Athens, and followed established bioarchaeological protocols regardi
Results suggest that a single female is equally good at producing a 2nd brood as a pair, and that female density during the 1st oviposition period does not influence the size of the 2nd brood. Female residence time with the 1st brood, body size, weight and lipid content explained little of the large variation in 2nd brood size. -from Authors
The external differences between the well‐documented S. scolytus and the little studied S. laevis are clarified with the help of SEM micrographs of the frons and abdomen of both sexes of the two species. The convex frons of both male and female S. scolytus is densely covered with short hairs. S. laevis males have a flat frons with long hairs in a pair of bundles, whereas the females have a convex
Two rings of pheromone-baited sticky traps surrounded the elm wood at 20-300m and 1-2km outside the forest edge. Most Scolytus were caught at sites in the inner ring near the forest; <1% of the total were caught in the outer ring. Emergence from logs and trap catches showed a first peak in July. Flight activity was recorded from the end of May to September for both species. A 2nd peak of activity
A model is presented that describes the reemergence of parent spruce bark beetles, Ips typographus, based on breeding density and temperature conditions. Laboratory data obtained at one constant temperature provide the distribution of reemergence time and different combinations of threshold temperatures and degreedays (°D) at mean reemergence. Of these combinations, 167.71 °D above 7.5 °C gave the
Parents re-emerged sooner at higher densities but the total proportion that re-emerged was independent of density. Over 20 offspring per female were produced at the lowest density (0.5/100 cm2) but only 0.6 per female at the highest density (31/100 cm2). Offspring from the lowest density were about 50% heavier than those from the highest density and also the fat content increased with decreasing d
An experiment to investigate the dispersal and supposed reattack by parent spruce bark beetles, Ips typographus (L.), was performed. More than 20,000 parent beetles were marked with fluorescent powder and immediately released from platforms when they reemerged from trees attacked during the spring swarming. Thirty‐eight marked and over 8000 unmarked beetles were trapped on sticky traps covering 21
Summary Objective There is limited knowledge on sick leave associated with arthroscopic partial meniscectomy (APM) due to traumatic meniscal tear and its potential gender differences. Thus, our aim was to determine gender-specific sick leave before and after APM. Method In Skåne region, Sweden, we identified patients, aged 18–59 years diagnosed with traumatic meniscal tear without ligament injury,
Lidar is a powerful technique normally associated with atmospheric monitoring. However, lidar techniques, also of the laser-induced fluorescence and laser-induced breakdown spectroscopy varieties, provide many new possibilities in unconventional fields including cultural heritage and ecological applications.
