11 torthaí
Both enantiomers and the racemate of alpha-pinene were transformed by Picea abies cells immobilised on alginate. The main products were cis- and trans-verbenol, the later being further transformed to verbenone. The enantiomeric purity of each product more or less corresponded to that of the
The enantiomeric composition of α-pinene in individual Norway spruce trees [Picea abies (L.) Karst.] was determined on a chiral GC column after stereoselective hydroboration-oxidation followed by a reaction with isopropyl isocyanate to form the carbamate derivative. The enantiomeric composition
Six yeast strains have been isolated and identified from the spruce bark beetle,Ips typographus. We have studied the ability of the yeasts to interconvertcis-verbenol,trans-verbenol, and verbenone. (1S)-cis-Verbenol is an active component in the aggregation pheromone ofIps typographus. The
Volatiles from hindgut extracts of males of the Qinghai spruce bark beetle, Ips nitidus, from different attack phases (phase 1: unpaired males and phases 2-4: males joined with one to three females) and hindgut extracts of mated females were analyzed by gas chromatography-mass spectrometry
alpha-Pinene, both as the pure enantiomers and as the racemate, was transformed mainly to trans-verbenol by treatment with a Picea abies suspension cell culture. These reactions were followed by a slow transformation of the verbenol to verbenone, which was not transformed further. trans-Pinocarveol,
Ips typographus beetles were collected in the field, separated into eight attack phases (from beetles walking on the trunk of a tree under attack to those excavating gallery systems with a mother gallery longer than 4 cm), and immediately frozen in liquid nitrogen. 2-Methyl-3-buten-2-ol,cis-
We treated Norway spruce (Picea abies) stems with methyl jasmonate (MeJA) to determine possible quantitative and qualitative effects of induced tree defenses on pheromone emission by the spruce bark beetle Ips typographus. We measured the amounts of 2-methyl-3-buten-2-ol and (S)-cis-verbenol, the
Six compounds previously identified from hindguts of unmated maleIps typographus (L.) during host colonization: 2-methyl-3-buten-2-ol (MB),cis-verbenol (cV),trans-verbenol (tV), myrtenol (Mt),trans-myrtanol (tM), and 2-phenylethanol (PE), were tested for their attractivity in the field with a
Volatiles released from individual entrance holes of eight spruce bark beetles (Ips typographus) were collected during the first week of attack on a resistant host tree. In order to quantify the release of the highly volatile 2-methyl-3-buten-2-ol (MB) from attacking males, a new method was
Eastern Palearctic conifers are subject to frequent bark beetle outbreaks. However, neither the species responsible nor the semiochemicals guiding these attacks are well understood. Two high-mountain Ips species on Qinghai spruce, Picea crassifolia, I. shangrila and I. nitidus, are typical in this
Volatiles from leaves or bark of nonhost birch (Betula pendula) and Norway spruce (Picea abies) dramatically reduced the attraction of the bark beetle, Pityogenes bidentatus (Coleoptera: Scolytidae), to their aggregation pheromone components (cis-verbenol and grandisol) in the field. In addition,