We examined the ̄oristic signi®cance of soil seed banks in relation to valley, midslope and ridge sites in a 70±90-year old forest in northeastern Connecticut. A-horizon mineral soils were collected to 5 cm depth in the early spring from forest understory sites across the topography. Samples from each of the sites were exposed to full sun within a greenhouse. Records of germination were made at...

The impact of ozone (O3) on the production and utilization of photoassimilates was examined in Plantago major population ‘Valsain’. Plants were exposed in controlled environment chambers to either charcoal/Purafil-filtered air (CFA) or CFA plus O3 (15 nmol mol −1 O3 overnight rising to a maximum of 75 nmol mol −1 between 12:00 and 16:00 h). Measurements of leaf gas exchange and non-structural c...

A hexane extract of Plantago major was investigated by bioactivity-directed fractionation, using an in vitro cyclooxygenase-2 (COX-2) catalyzed prostaglandin biosynthesis inhibition assay, and resulted in the isolation of ursolic acid (1). This triterpenoid showed a significant COX-2 inhibitory effect, directly on the enzyme activity, with an IC50 value of 130 microM and a COX-2/COX-1 selectivi...

In surveys of apple-production areas east of the Cascade Mountains of Washington, broadleaf plantain, Plantago major Linnaeus (Plantaginaceae) was common throughout while narrowleaf plantain, P. lanceolata Linnaeus, was most common south of Orondo, Douglas County (47.7u latitude). Rosy apple aphid was the most common aphid on these two herbaceous plants; however, colonies were scarce, on only 1...

In the present study we report the isolation of a phenylpropanoid glucoside, plantamajoside, together with rosmarinic acid, chlorogenic acid and luteolin-7-O-monoglucoside. This is the first report of these compounds from Plantago lagopus.

High levels of mRNA for the sucrose-H+ symporter PmSUC2 have been found in the vascular bundles of petioles from Plantago major. The possible role of PmSUC2 in phloem loading was studied with antiserum raised against the recombinant PmSUC2 protein. This antiserum labeled a single 35-kD protein band in detergent extracts of P. major vascular bundles. It showed no cross-reaction with the P. major...

Effects of vesicular-arbuscular mycorrhizal (VAM) infection and P on root respiration and dry matter allocation were studied in Plantago major L. ssp. pleiosperma (Pilger). By applying P, the relative growth rate of non-VAM controls and plants colonized by Glomus fasciculatum (Thaxt. sensu Gerdemann) Gerdemann and Trappe was increased to a similar extent (55-67%). However, leaf area ratio was i...

BACKGROUND AND AIMS Leaf mechanical properties, which are important to protect leaves against physical stresses, are thought to change with light and nutrient availabilities. This study aims to understand phenotypic changes of leaf mechanical properties with respect to dry mass allocation and anatomy. METHODS Leaf lamina strength (maximum force per unit area to fracture), toughness (work to f...