| descriptions of meloidogyne camelliae n.sp. and m. querciana n.sp (nematoda:meloidogynidae), with sem and host-range observations. | meloidogyne camelliae n.sp. on camellia (camellia japonica) from japan and m. querciana n.sp. on pin oak (quercus palustris) from virginia, usa, are described and illustrated. m. camelliae n.sp. is distingnishable from other species of the genus especially by its striking perineal pattern having heavy ropelike striae forming a squarish to rectangular outline with shoulders or projections, appearing sometimes ahnost starlike. m. querciana differs from other species by its characteristic perineal ... | 1979 | 19305554 |
| first report of northern root-knot nematode, meloidogyne hapla, parasitic on oaks, quercus brantii and q. infectoria in iran. | root-knot nematodes (rkn) are the most serious plant parasitic nematodes having a broad host range exceeding 2,000 plant species. quercus brantii lindl. and q. infectoria oliv are the most important woody species of zagros forests in west of iran where favors sub-mediterranean climate. national botanical garden of iran (nbgi) is scheduled to be the basic center for research and education of botany in iran. this garden, located in west of tehran, was established in 1968 with an area of about 150 ... | 2015 | 25861121 |
| floral affinity and benefits of dietary mixing with flowers for a polyphagous scarab, popillia japonica newman. | many generalist herbivores, especially adult beetles, are facultative florivores, feeding on leaves but readily accepting floral tissues when available. we speculated that day-flying beetles with high energetic requirements would benefit from dietary mixing with nutrient-rich flower tissues and favor them during foraging. we tested that "floral affinity hypothesis" with popillia japonica, a day-active ruteline scarab that feeds intermittently throughout its adult life on multiple plant species. ... | 2004 | 15146324 |
| importance of fragmentation-tolerant species as seed dispersers in disturbed landscapes. | forest fragmentation can negatively affect plants if animal seed-dispersers become locally extinct in fragments. we conducted a 2-year experiment to evaluate the importance of tree squirrels (sciurus) as seed dispersers for quercus, carya, and juglans, and to assess dispersal consequences in patches where fragmentation-sensitive eastern gray squirrels (sciurus carolinensis) are absent. we accounted for fates of approximately 15,700 seeds from five tree species in four exclosure treatments at 18 ... | 2007 | 17180374 |
| acetaldehyde and ethanol biosynthesis in leaves of plants. | leaves of terrestrial plants are aerobic organs, and are not usually considered to possess the enzymes necessary for biosynthesis of ethanol, a product of anaerobic fermentation. we examined the ability of leaves of a number of plant species to produce acetaldehyde and ethanol anaerobically, by incubating detached leaves in n(2) and measuring headspace acetaldehyde and ethanol vapors. greenhouse-grown maize and soybean leaves produced little or no acetaldehyde or ethanol, while leaves of several ... | 1987 | 16665585 |
| seasonal effect on tree species classification in an urban environment using hyperspectral data, lidar, and an object- oriented approach. | the objective of the current study was to analyze the seasonal effect on differentiating tree species in an urban environment using multi-temporal hyperspectral data, light detection and ranging (lidar) data, and a tree species database collected from the field. two airborne imaging spectrometer for applications (aisa) hyperspectral images were collected, covering the summer and fall seasons. in order to make both datasets spatially and spectrally compatible, several preprocessing steps, includi ... | 2008 | 27879863 |
| effects of weevil larvae on acorn use by blue jays. | blue jays (cyanocitta cristata l.) are important consumers and dispersers of the nuts of oaks and other fagaceous trees in eastern north america. acorns compose much of the jay diet, especially during the autumn when jays may consume or cache a significant portion of an acorn crop. however, jays do not appear to possess physiological adaptations for countering the protein-binding properties of secondary compounds (tannins) found in acorns. we offered captive blue jays a mixture of infested and u ... | 1997 | 28307995 |
| dogwood borer (lepidoptera: sesiidae) infestation of horned oak galls. | pin oak, quercus palustris muenchhausen, is the primary host for the gall wasp callirhytis cornigera (osten sacken). woody stem galls formed by c. cornigera may be infested by the dogwood borer, synanthedon scitula (harris), an important pest of flowering dogwood, cornus florida l. previous research has shown that s. scitula has a bimodal seasonal flight pattern, with peaks in late spring and midsummer. we tested the hypothesis that moths emerging from dogwoods largely account for the first flig ... | 2000 | 10902327 |
| additive and nonadditive effects of herbivory and competition on tree seedling mortality, growth, and allocation. | the interaction between simulated cotyledon herbivory and interspecific competition was studied in a greenhouse experiment using two species of trees, acer rubrum and quercus palustris, which commonly invade abandoned agricultural fields. herbivory treatments were applied as a gradient of cotyledon removal for a. rubrum with 0, 25, 50, 75, and 100% of cotyledon tissue removed. cotyledons from q. palustris were clipped and removed (control, early, and late removal) to create a gradient of seed re ... | 2000 | 11118420 |
| acorn dispersal by the blue jay (cyanocitta cristata). | blue jays transported and cached 133,000 acorns from a stand of quercus palustris trees in blacksburg, virginia, representing 54% of the total mast crop. a further 20% (49,000) of the mast crop was eaten by jays at the collecting site. a large proportion of the nuts remaining beneath the collecting trees was parasitized by curculionid larvae. the number of nuts transported per caching trip ranged from 1-5 with a mean of 2.2. mean distance between seed trees and caches was 1.1 km (range: 100 m-1. ... | 1981 | 28311093 |
| does multiple seed loading in blue jays result in selective dispersal of smaller acorns? | studies from both tropical and temperate systems show that scatter-hoarding rodents selectively disperse larger seeds farther from their source than smaller seeds, potentially increasing seedling establishment in larger-seeded plants. size-biased dispersal is evident in many oaks (quercus) and is true both across and within species. here, we predict that intraspecifc variation in seed size also influences acorn dispersal by the blue jay (cyanocitta cristata linnaeus), but in an opposite manner. ... | 2011 | 21910843 |
| probability of tree seedling establishment changes across a forest-old field edge gradient. | forest edges affect many aspects of plant communities, causing changes in microclimate, species composition, and community structure. however, the direct role of edges in regulating forest regeneration is relatively unknown. the pattern of tree establishment across a forest-old field edge was experimentally examined to determine the response of three tree species to the edge gradient. we placed 100 1-m(2) plots in a 90 × 90 m grid that began 30 m inside the forest, extended across the edge, and ... | 2002 | 21665643 |