concentration and size of induced lesions were determined following inoculation of stems of slash pine (Pinus elliottii Englm. var. elliottii) and loblolly pine (Pinus taeda L.) with Ophiostoma minus (Hedgc.) H.P. Sydow, O. ips (Rumb.) Nannf or sterile water. In a second experiment, the rate of ethylene production and monoterpene concentration were determined following inoculation of slash pine...

[1] Mixing ratios and emission rates of monoterpenes were measured above a ponderosa pine plantation in the Sierra Nevada mountains before, during and after a precommercial thinning in spring 2000. The thinning removed and left onsite approximately one half of the plantations biomass. Monoterpene fluxes increased tenfold during the thinning and pinene mixing ratios in excess of 3 ppb were obser...

Peppermint (Mentha x piperita L.) was independently transformed with a homologous sense version of the 1-deoxy-d-xylulose-5-phosphate reductoisomerase cDNA and with a homologous antisense version of the menthofuran synthase cDNA, both driven by the CaMV 35S promoter. Two groups of transgenic plants were regenerated in the reductoisomerase experiments, one of which remained normal in appearance ...

New approaches directed to unraveling monoterpene metabolism and secretion and recent progress in transformation protocols have set the stage for the systematic genetic engineering of essential oil production. This article focuses on specific strategies to improve the quality and quantity of mint essential oils.

Ceratocystis coerulescens RWD 451 (Ascomycetes) was cultivated on defined synthetic culture medium containing glucose (3.0% ), asparagine (0.1% ), mineral salts and thiamine. 6 weeks oid cultures produced methyl heptenyl compounds, citronellol. citronellyl acetate, dihydro-farnesol and a hitherto unknown monoterpene alcohol. By GC/MS, 'H and l3C NMR spectroscopy, this alcohol could be identifie...

Quercus ilex (L.) leaves emit monoterpenes, particularly alpha-pinene, beta-pinene and sabinene. Apart from the monoterpene pools that are stored in specialized structures and have a clear defensive or attractive role, the function of monoterpenes in Q. ilex leaves is unknown. We tested whether monoterpenes have an antioxidant role, as has previously been found for isoprene in isoprene-emitting...

Circumstantial evidence based on ultrastructural correlation, specific labeling, and subcellular fractionation studies indicates that at least the early steps of monoterpene biosynthesis occur in plastids. (4S)-Limonene synthase, which is responsible for the first dedicated step of monoterpene biosynthesis in mint species, appears to be translated as a preprotein bearing a long plastidial trans...

Cryofixation and conventional chemical fixation methods were employed to examine the ultrastructure of developing peltate glandular trichomes of peppermint (Mentha x piperita). Our results are discussed in relation to monoterpene production and the mechanism of essential oil secretion. Peltate glands arise as epidermal protuberances (initials) that divide asymmetrically to produce a vacuolate b...