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... Ecotype formation in eight populations of Echium leucophaeum was studied on La Palma (Canary Islands) at 100—m intervals from sea level to 600 m elevation. Climate varied with altitude, the lower elevation having higher temperatures, evaporation, and wind velocity and lower rainfall. A method for recording growth form of individual plants was developed whereby lateral branch production and branchi ...
Glycine max; application rate; benzoic acids; branches; branching; chemical composition; crop production; growth regulators; leaves; mechanism of action; oils; plant growth; plant height; pods; polyethylene glycol; sorbitol; soybeans; surfactants; Great Plains region
Abstract:
... Some growth regulators studied for morphological and yield effects on soybeans [Glycine max (L.) Merr.] have not been studied for chemical compositional effects, particularly under Great Plains conditions. The objective of this study was to compare morphological aud mature seed compositional responses of 11 growth regulators. Eleven growth regulators of various modes of action were applied at two ...
... Les effets du rognage et la suppression des entre-coeurs sur le cépage Tempranillo ont été étudiés en 1986, dans deux vignobles de la Rioja Alavesa. L'essai comprenait 560 souches considérées individuellement. Le rognage augmente la production et diminue le degré alcoolique probable. La suppression des entre-coeurs donne les meilleurs résultats, quand elle est faite au début de la floraison, mais ...
... An understanding of the environmental influences on branch initiation and growth is essential for developing mechanistic models that simulate crop behavior. In this study shading was used to determine how limited C availability affects the timing and location of branches in soybean [Glycine mar (L.) Merr.] plants grown outdoors. Carbon availability was limited by covering the plants with 66% shade ...
... Patterns of aboveground growth, branching, and leaf display were examined in saplings of Acer saccharum Marsh. (sugar maple) and Fagus grandifola Ehrh. (beech) to determine (1) the responses of aboveground growth rates to variation in forest light regimes and (2) the importance of branching and leaf display patterns to the ability of saplings of these two species to respond to changes in forest li ...
... Increases in size inequalities with time in cohorts of plants have been attributed to two causes: (1) variation in the exponential relative growth rates (RGR) of plants and (2) asymmetry of competitive interactions, whereby large plants can more readily suppress the growth of smaller neighbors than vice versa. It follows, then, that species with a longer exponential growth phase should develop gre ...
... Nonstructural carbohydrate concentrations in stems are greater for sweet than grain sorghums [Sorghum bicolor (L.) Moench). Knowledge of plant characteristics associated with high nonstructural carbohydrates in sweet sorghum will aid efforts to increase nonstructural carbohydrates in grain sorghum stems. This study tested the hypothesis that variation of CO₂ assimilation rate, leaf area, branching ...
Andropogon gerardii; Coreopsis; Solidago altissima; branches; branching; chronosequences; fibrous roots; field experimentation; forbs; mycorrhizal fungi; roots; soil; warm season grasses
Abstract:
... A field study was conducted across a chronosequence of tallgrass prairie restorations to investigate the influence of plant's neighbor may have on its gross root morphology and association with mycorrhizal fungi. The root systems of a warm—season grass, Andropogon gerardii, and two perennial forbs, Coreopsis tripteris and Solidago altissima, were sampled by excavating soil blocks representing all ...
... Effects of proximity to nearest neighbours on shoot morphology and branch growth were examined for Senna obtusifolia (L.) I. '' B., an annual legume species that displays wide variation in branching. Periodic surveys described location and type of growth at all nodes on plants in regularly spaced monocultures. Stands with interplant distances of 15-50 cm (51-5 plants m⁻²) formed closed canopies wi ...
Zea; branches; branching; corn; meristems; roots; transpiration; water uptake; xylem
Abstract:
... The late metaxylem (LMX) in the first‐order branch roots of maize matures slowly. Fully lignified elements remain as individual cells of mean diameter 67 μm and length about 2 mm for considerable distances proximal from the tip of branches that retain an active meristem (indeterminate branches). Such branches, depending on their age, have from 0 to 45%, of the Total length of LMX conduits mature a ...
... The unique marine ecosystems of coral reefs express varying levels of degradation as a result of increasing anthropogenic pressures. This is the main reason why more than 200 coral reef localities were proclaimed as natural reserves or marine parks under varying legislation, rules, and monitoring and management programs. Ironically, the conventional management plans increased accessibility to many ...
... Plant density and sowing date were shown to affect branching in spring-sown white lupin (Lupinus albus L.), but the response varied among environments. The patterns of primary and secondary branching in the cv. Lublanc were studied as a function of both the number of axillary buds and the plant growth rate. Field experiments that used a wide range of sowing dates and plant densities to alter plant ...
Abies sachalinensis; Picea glehnii; plant morphology; canopy; coniferous forests; dimensions; branches; branching; age; stand density; tree trunk; natural pruning
Abstract:
... Crown architecture and growth rate of trunk height, trunk diameter and lateral branches of understorey trees (5-10 m tall) were compared between two co-dominating conifers, Abies sachalinensis and Picea glehnii, in relation to the index of local crowding intensity, W, represented as a function of density, distance and basal area of taller neighbours. For the two conifers, the growth of trunk heigh ...
... A flexing machine was used to examine influences of mechanical perturbation on the growth of Sitka spruce (Picea sitchensis (Bong.) Carr.). Eight plants of each of 10 clones were flexed for 196 days, adjacent to unflexed control plants. Plants were grown at two nutrient regimes to determine if nutrient availability affected plant response to stimulation. Flexing had no significant effect on shoot ...
Trifolium fragiferum; biomass production; branches; branching; canopy; clones; field experimentation; flowering; ground vegetation; meristems; petioles; progeny; sexual reproduction; shade; vegetation
Abstract:
... In herbaceous canopies light availability can show high degrees of spatial variability in a vertical and also in a horizontal direction. Stoloniferous plants are hence likely to encounter differences in light availability during their ontogenetic development. Different mechanisms, such as petiole elongation, plasticity in internode length and branching, and an enhanced allocation to sexual reprodu ...
Taxus brevifolia; plant morphology; branches; tree age; branching; solar radiation; vigor; inflorescences; Oregon
Abstract:
... Strobilus production, growth, and morphology of Pacific yew (Taxus brevifolia Nutt.) were examined at three sites in the Cascade Mountains and one site in the Willamette Valley of western Oregon. Strobilus production on branch segments was positively associated with overstory openness for male and female trees at all four sites over 2 years. Strobilus production was also associated with branch vig ...
... Elaeocarpus hookerianus Raoul is a profoundly heteroblastic tree native to New Zealand. We describe and quantify changes in leaf morphology and anatomy, and in branching pattern at different levels of insertion. Discrete juvenile, adolescent and adult phases were identified. The divaricating juvenile bore small leaves with thin laminae and an anatomy typical of shade-plants. Juveniles had dense ca ...
... Homogeneously developed oak (Quercus robur L.) microcuttings were challenged in a Petri‐dish system with the mycobionts Piloderma croceum J. Erikss. & Hjortst. and Paxillus involutus (Batsch) Fr. Non‐destructive observations over 10 wk followed by d. wt measurements at the end of the assays served to precisely characterize root and shoot development, dynamics of mycorrhizal colonization and morpho ...
abscisic acid; air drying; branches; branching; corn; drought; models; root tips; root water potential; shoots; water content
Abstract:
... How much ABA can be supplied by the roots is a key issue for modelling the ABA-mediated influence of drought on shoot physiology. We quantified accumulation rates of ABA (SABA) in maize roots that were detached from well-watered plants and dehydrated to various extents by air-drying. SABA was estimated from changes in ABA content in root segments incubated at constant relative water content (RWC). ...
... Altogether 15 root systems, five at each of three plots (north- and south-facing slopes and plateau), of 40-year-old Picea abies (L.) Karst. trees with different symptoms of forest decline were excavated down to a root diameter of 0.5 cm. The object was to investigate the variability of root morphology and to assess the influence of environmental variation on the architecture of the woody root sys ...
... Although the basal and uppermost lateral branches of Lupinus angustifolius L. frequently grow and contribute to yield, buds formed in the axils of leaves 6-12 (referred to as middle buds) rarely grow. This may be due to an inherent limitation of these buds, or some form of apical dominance or competition imposed by the plant. The hypothesis that middle buds have the full capacity to grow, but rema ...
... The concentrations of indole-3-acetic acid (IAA), cytokinins (CK) and abscisic acid (ABA) were measured in buds of different regions (main stem and lateral branches) of Lupinus angustifolius L. (cv. Merrit) and at different stages in the development of branches. In lupin, branching patterns are the result of discrete regions of axillary branches (upper, middle and basal) which elongate at much dif ...
... The complex structure of the crown of Cornus kousa, generally five-forked in vegetative branching and two-forked in reproductive branching, is analysed quantitatively and described by two basic branching principles: decussate phyllotaxy and the resetting rule for planes of branching. Most Cornus species have opposite, decussate phyllotaxis. The leaf pair (with axillary buds) defines the branching ...
mathematical models; canopy; diameter; growth rings; tree age; branching; height; stand density; Pinus sylvestris; length; soil fertility; branches; Finland
Abstract:
... Branch growth dynamics in Scots pine (Pinus sylvestris L.) were studied in 19 thinning experiments in southern and central Finland. Data were collected from 229 trees growing on sites of different fertility with different stand density, age, and canopy position. Radial increments were measured from discs from the base of the thickest branch on every fifth living whorl. Branch growth declined gradu ...
... The morphology and architecture of young Nothofagus pumilio plants growing as understorey and in a cleared area were assessed. Length, number of internodes, presence of branches and apex condition were registered for each growth unit (GU) in the sampled plant. GUs were grouped according to branching order and age of the bearing axis. Understorey plants were seven years old and had a short trunk be ...
... Apical control is the inhibition of a lateral branch growth by shoots above it (distal shoots). If the distal shoots are cut off to remove apical control, the lateral branch can grow larger and may bend upwards. Apical control starts when new lateral buds grow after passing through a period of dormancy. Buds initially break and produce leaves, then apical control is exerted and the lower (proximal ...
... In the Origin of Maize Controversy, the Orthodox Teosinte Hypothesis (OTH; Beadle 1939, 1972; Iltis 1971), five key mutations change 2-ranked (distichous) ears of teosinte (wild Zea) with a single row of grains per rank to 4- to many-ranked (polystichous) maize ears with a double row of grains per rank. BUT teosinte ears are lateral to the 1° branch axes, maize ears, like their male homologues, th ...
... The length and basal diameter of all lateral and terminal buds of vegetative annual shoots of 7-year-oldJuglans regia trees were measured. All buds were dissected and numbers of cataphylls, embryonic leaves and leaf primordia were recorded. Each axillary bud was ranked according to the position of its associated leaf from the apex to the base of its parent shoot. Bud size and content were analysed ...
Laingia; blades; branches; branching; cell division; Australia
Abstract:
... Hemineura is endemic to Australia and the sole member of the ‘Hemineura-Gruppe’, an informal taxon, equivalent to a tribe, that Kylin defined primarily by its bicarpogonial supporting cells. We have found that supporting cells carry not only two carpogonial branches but also two sterile groups, a type of procarp not known for any other member of the family Delesseriaceae or the order Ceramiales. T ...
Helminthocladia; branches; branching; new species; planting; Canary Islands; Spain
Abstract:
... The type species of Helminthocladia, Helminthocladia calvadosii, and two species known from the eastern Atlantic and Mediterranean, H. agardhiana and H.reyesii O'Dwyer & Afonso-Carrillo sp. nov., are described in detail. The species are mainly distinguishable by their habit, the morphology of the cortical fascicles, and the type of carposporangium (undivided single terminal, quadripartite single t ...
... This study describes the successive stages of development of branches from axillary buds in fully rooted plants of Trifolium repens grown in near optimal conditions, and the way in which this developmental pathway differs when nodal root formation is prevented as plants grow out from a rooted base. Cuttings of a single genotype were established in a glasshouse with nodal root systems on the two ba ...
cultivars; flowering; branching; plant growth substances; pears; fruit quality; spring; trees; extinction; fruit growing; pests; pruning; branches; fruiting; shoots; France
Abstract:
... Tree architecture traits are often described in relation to planting densities, tree height or adaptation of the tree to mechanical pruning. The need to reduce both pruning costs and the use of plant growth regulators (PGRs), notably in a context of integrated fruit production (IFP), lends further support to the development of architectural analysis as an aim in itself. A research program at the I ...
... The fine roots of trees are concentrated on lateral branches that arise from perennial roots. They are important in the acquisition of water and essential nutrients, and at the ecosystem level, they make a significant contribution to biogeochemical cycling. Fine roots have often been studied according to arbitrary size classes, e.g., all roots less than 1 or 2 mm in diameter. Because of the size c ...
... Velvetleaf growth and canopy architecture were compared under a range of light conditions representative of competitive and noncompetitive environments typical of irrigated Mediterranean-type agroecosystems. Velvetleaf biomass and seed production exceeded those reported in the literature. Plants grown in full light produced 1,370 g dry weight and 44,200 seeds per plant and showed low relative vari ...
... Only a few sage cultivars have been selected until now, which can be still characterised by quite high individual variability. Further exploitation and analysis of individual variability seem to be necessary for successful improvement of populations. Eighty-five individuals of a sage population of a synthetic cultivar ('Antella') had been detail studied for their morphological and chemical charact ...
... Acanthophora nayadiformis is a perennial species of red alga that overwinters by means of a rhizomatous prostrate system; both reproductive and vegetative plants are also able to spread by means of specialized vegetative propagules that have never been reported in other Acanthophora species. A detailed study of thallus morphology has highlighted four kinds of primordia in this species, distinct in ...
... To gain a better understanding of the effects of spatial structure on patterns of neighbourhood competition among hardwood trees, the three-dimensional extension of primary branches was surveyed for ten community-grown Castanea crenata (Fagaceae) trees with respect to the positioning of neighbouring branches and the slope of the forest floor. There were significantly more branches extending toward ...
... The monopodial shoot axis of petunia (Petunia hybrida Vilm) has two different patterns of branch development. Basal lateral branching develops acropetally and is limited to a discrete number of nodes that correlate with the late rosette phase of growth (Zone II). Two zones of suppressed buds immediately precede and follow this zone of branching. Apical branching occurs in response to flowering, de ...