abstract to study the effects of four types of mulches including wood chips, municipal compost, sawdust and gravel in three different thicknesses on growth of platanus orientalis during two years, an experiment was conducted in mashhad area with semi-arid climate. the research was conducted as split plot based on a completely randomized block design with four replications. treatments included c...

Intensity-modulated radiation therapy (IMRT) represents one of the most significant technical advances in radiation therapy. In the dynamic multileaf collimator (MLC) method of IMRT delivery, because of the relatively small gaps between opposed leaves and because most regions are shielded by leaves most of the time, the delivered dose is very sensitive to MLC leaf positional accuracy. A variati...

Cuttings from a single American sycamore clone were rooted and grown under four levels of artificial shade: 27, 45, 72 and 100 percent of full sunlight to learn more about the ecological role of this species in deciduous forests of the Southern Appalachians. After 132 days, leaf angle, leaf area, leaf thickness, stomatal frequency and size, and dry matter production of the leaves, stem, and roo...

The anatomical and morphological leaf traits as well as leaf inclination and orientation per different leaf age cohort of Quercus ilex, Phillyrea latifolia and Cistus incanus growing in the Mediterranean maquis along Rome’s coast-line (Italy) were investigated. Specific leaf weight (SLW), total leaf thickness (L), leaf density index and leaf inclination (a) changed according to leaf age. The ma...

Leaf characteristics of mature 2, 3 and 4-year-old North American ginseng (Panax quinquefolius L.) leaves on fruiting and non-fruiting (NF) plants were studied. Leaflets of the 2-year-old plants had the lowest fresh and dry weight, area, volume and internal gas volume. Inflorescence removal in 3-year-old plants did not affect leaf characteristics or ginsenoside concentration but in 4-yearold pl...

Leaf shape, including leaf size, leaf dissection index (LDI), and venation distribution, strongly impacts leaf physiology and the forces of momentum exerted on leaves or the canopy under windy conditions. Yet, little has been known about how leaf shape affects the morphological response of trees to wind load. We studied eight Quercus species, with different leaf shapes, to determine the morphol...

The broad-band ultrasonic spectroscopy technique allows the determination of changes in the relative water content (RWC) of leaves with contrasting structural features. Specifically, the standardized frequency associated with the maximum transmittance (f/f(o)) is strongly related to the RWC. This relationship is characterized by the existence of two phases separated by an inflexion point (assoc...

As sugar beet source leaves lowered the CO(2) concentration to compensation point in a closed atmosphere, leaf thickness and relative water content decreased. Leaf water potential declined rapidly from -0.5 to -1.4 megapascals. At 340 microliters CO(2) per liter, water potential and sucrose, glucose, and fructose contents were steady in photosynthesizing source leaves. Within 90 minutes after l...

For genetic analysis of mechanisms of leaf morphogenesis, we chose Arabidopsis thaliana (L.) Heynh. as a model for leaf development in dicotyledonous plants. Leaves of the angustifolia mutant were the same length as but narrower and thicker than wild-type leaves. The total number of cells in leaf blades of angustifolia plants was the same as in the wild type. At the cellular level in the angust...