The present work was carried out to evaluate how plant growth and cultural practices influence the amount and composition of cuticular waxes on leaves of rose cultivars. The total amount of cuticular wax per leaf area was higher for rose cultivar Apollo Parade than for Charming Parade. Both cultivars had waxes dominated by alkanes, with the major alkanes being the C31 and C33 homologues. Primary alcohols were the next most abundant constituent class, with C26 as the dominant homologue. Compared with Charming Parade, Apollo Parade had higher proportions of its total wax load as primary alcohols but lower acids and aldehydes. The proportion of alkanes in the total load on these cultivars was similar. Commercially produced roses are routinely treated with paclobutrazol (PBZ) to retard growth. PBZ treatments caused a 10% increase in total wax load and changes in the proportions of certain wax constituents within 11 days of application. Notable was an increase in the total proportion of acids in the total load 25 days after PBZ application, primarily because of increased C28 acids. An alternative method of retarding plant growth is production of roses under limited water availability. When Apollo Parade roses experienced periods of moderate drought stress during production, the wax load per leaf area increased 14 and 8% above control levels at 24 and 38 days after imposition of drought, respectively. Drought caused similar changes in the proportions of individual wax constituents as did PBZ application.

We report on a novel experiment sensitive to the anisotropy of the one-way speed of light. The frequency of a two-photon transition in a fast atomic beam is compared to the frequency of a stationary absorber while the direction of the fast beam is rotated relative to the fixed stars. The experiment yields an improved upper limit for the anisotropy: Ac/c < 3 x 10 ~9.

Global climate models predict an increase in the mean surface air temperature, with a disproportionate increase during winter. This study documents that even a very modest temperature increase during the colder periods of a plant's annual cycle may delay dormancy release and advance bud burst and flowering in blackcurrant, but the magnitude of the responses varies between genotypes differing in chilling requirement. Winter warming additionally has a large carryover effect into the growing season by reducing fruit yield the following summer.

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