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The beech leaf-mining weevil, Orchestes fagi L. ( Curculionidae: Curculioninae: Rhamphini), a pest of European beech, Fagus sylvatica L. ( Fagaceae), was recently discovered infesting American beech, Fagus grandifolia Ehrh., in Nova Scotia, Canada. Adult O. fagi feed on both young and mature leaves of beech as well as on other species (e.g., raspberry, Rubus spp.), but oviposition and larval feeding are restricted to beech. Females oviposit in young developing beech leaves at the time of bud burst. We characterized volatiles emitted from buds, leaves, and sapwood of American beech and examined their potential as attractants alone or when combined with other weevil pheromones for O. fagi. We predicted that adults would be attracted to volatiles emitted from beech leaves, especially those emitted from bursting beech buds. Gas chromatography/mass spectrometry ( GC/ MS) analyses of volatiles collected from buds at pre- and post-budburst identified two diterpene hydrocarbons, 9-geranyl- p-cymene ( 1) and 9-geranyl-α-terpinene ( 2a), that were emitted in large amounts at the time of bud burst. Compound 1 significantly increased mean catch of males and total O. fagi (but not females) on sticky traps compared with unbaited controls. Y-tube bioassays confirmed attraction of male O. fagi to bursting beech buds and compound 1. Attraction of male O. fagi to 1, emitted in large quantities from American beech, is likely adaptive because both oviposition and mating of O. fagi coincide with budburst. Our data suggest that traps baited with 1 may be useful for monitoring the spread of O. fagi in North America. [ABSTRACT FROM AUTHOR]

Emerald ash borer (EAB),Agrilus planipennisFairmaire, is an invasive insect that has killed millions of ash trees in Canada and the USA. (3Z)-Dodecen-12-olide is a known female-produced pheromone of this insect, and a concise, three-step synthesis of a 2:1 blend of (3Z)-dodecen-12-olide and (3E)-dodecen-12-olide starting from commercially available (2-carboxyethyl)triphenylphosphonium bromide and 10-bromo-1-decene is described. The key steps in this synthesis are a lithium-salt-free Wittig reaction and an intramolecular SN2 esterification. Both of these macrocyclic lactones are behaviorally active toward EAB, and the 2:1 blend whose synthesis is described here has the potential to be a detection agent, mating disruptor, or mass trapping agent, which could be used in the control of EAB. [ABSTRACT FROM AUTHOR]

Emerald ash borer (EAB),Agrilus planipennisFairmaire, is an invasive insect that has killed millions of ash trees in the USA and Canada. A concise synthesis of a potential EAB pheromone component, (3E)-dodecen-12-olide, using highly stereoselective Julia–Kocienski olefination as the key step, is reported. Supplemental materials are available for this article. Go to the publisher's online edition ofSynthetic Communications® to view the free supplemental file. [ABSTRACT FROM PUBLISHER]

Although two billion people in the world are suffering from iodine deficiency there is little information on the chemical fate of iodine in the terrestrial environment. Here we show that peatlands play a major role in terrestrial iodine cycling. Chemical data from two peat profiles from Patagonia, Chile imply that transformation of iodine from its inorganic form to organoiodine compounds during early humification in peatlands is a key process in storage of iodine in the terrestrial environment. Once bound in peat, iodine remains stable for thousands of years. In the earth’s peatlands, net accumulation of iodine since the last glacial period is estimated to be 12–36 teragrams (1 Tg=1012 g). These data suggest that peatlands are a major reservoir of iodine in terrestrial ecosystems. Our novel model of iodine distribution in the terrestrial environment demonstrates the key role of peatlands in burial and reemission of organically bound iodine. [ABSTRACT FROM AUTHOR]