The Experts below are selected from a list of 234 Experts worldwide ranked by ideXlab platform
Timothy E. Martinson - One of the best experts on this subject based on the ideXlab platform.
-
colonization of new york vineyards by anagrus spp hymenoptera mymaridae overwintering biology within vineyard distribution of wasps and parasitism of grape leafhopper Erythroneura spp homoptera cicadellidae eggs
Biological Control, 2000Co-Authors: Livy Williams, Timothy E. MartinsonAbstract:Received February 16, 1999; accepted January 17, 2000 A study was conducted in New York to identify the Anagrus species present in vineyards, to determine the plants in which Anagrus species overwinter, and to characterize the dispersal of wasps and level of parasitism of grape leafhopper eggs in vineyards. Anagrus daanei S. Triapitsyn and Anagrus Erythroneurae S. Trjapitzin and Chiappini were the most abundant species reared from Vitis labrusca Bailey and Vitis vinifera L. cultivars, respectively. V. labrusca cultivars are infested predominantly by Erythroneura comes (Say), whereas V. vinifera cultivars are infested primarily by the Erythroneura vitifex Fitch‐Erythroneura bistrata McAtee complex. Anagrus tretiakovae S. Triapitsyn was reared from seven grape cultivars in approximately equal proportions. Thus, A. daanei and A. Erythroneurae appear to possess greater degrees of host specificity than A. tretiakovae. These results support the belief that, although Anagrus species have relatively broad host associations, host preferences do exist. These preferences may be mediated by the plant associations of particular leafhopper species. Anagrus species use alternate hosts that infest several plant species. In particular, diapausing insect eggs in Acer saccharum Marshall, Robinia pseudo-acacia L., Rosa multiflora Thunberg, Salix nigra L., Vitis riparia Michaux, and Zanthoxylum americanum Miller may play important roles in the overwintering biology of the Anagrus species that are most abundant in vineyards. Following emergence from overwintering hosts, Anagrus adults are aggregated at the vineyard edge early in the season (May and June). By midseason or later (August and September), the pattern of wasp colonization and parasitism indicates that parasitoids are more widely dispersed in the vineyards. This pattern is consistent with colonization from vineyard edges, followed by relatively slow dispersal into the vineyard interior. Further investigations are necessary to identify the alternate host(s) that Anagrus exploits during the winter and spring and to delineate the phenology of such alternate hosts, as well as that of the grape leafhoppers and Anagrus species in the spring. Habitat management studies could then be conducted to identify strategies that would accelerate population growth of Anagrus in the spring and increase the rate of dispersal into vineyards. © 2000 Academic Press
-
influence of temperature driven phenology and photoperiodic induction of reproductive diapause on population dynamics of Erythroneura comes homoptera cicadellidae
Environmental Entomology, 1995Co-Authors: Timothy E. Martinson, Timothy J DennehyAbstract:The influence of degree–day accumulations and photoperiodic induction of diapause on the phenology of Erythroneura Comes (Say) was investigated . In growth chamber experiments, nymphs reared at photoperiods of 710 degree days (DD) before 1 August are required to produce a 2nd generation of E. comes under climatic conditions in New York.Variationsin temperature–driven development are hypothesized to strongly influence year–to–year variability in leafhopper abundance. Degree–day accumulations by 30 June correlated well with degree–days by 1 August and may provide a useful early–warningsystem for predicting years in which leafhopper population densities are above average.
-
Influence of Temperature–Driven Phenology and Photoperiodic Induction of Reproductive Diapause on Population Dynamics of Erythroneura comes (Homoptera: Cicadellidae)
Environmental Entomology, 1995Co-Authors: Timothy E. Martinson, Timothy J DennehyAbstract:The influence of degree–day accumulations and photoperiodic induction of diapause on the phenology of Erythroneura Comes (Say) was investigated . In growth chamber experiments, nymphs reared at photoperiods of 710 degree days (DD) before 1 August are required to produce a 2nd generation of E. comes under climatic conditions in New York.Variationsin temperature–driven development are hypothesized to strongly influence year–to–year variability in leafhopper abundance. Degree–day accumulations by 30 June correlated well with degree–days by 1 August and may provide a useful early–warningsystem for predicting years in which leafhopper population densities are above average.
-
varietal preferences of Erythroneura leafhoppers homoptera cicadellidae feeding on grapes in new york
Environmental Entomology, 1995Co-Authors: Timothy E. Martinson, Timothy J DennehyAbstract:Species composition of Erythroneura leafhoppers infesting the 3 major classes of grapes grown in New York was investigated. Eastern grape leafhopper, E. comes (Say), comprised 74–100% of populations collected on the native American ( Vitis labrusca Bailey) cultivars ‘Concord’, ‘Niagara’, ‘Catawba’ and ‘Delaware’. On interspecific hybrid ( Vitis sp .) and Vitis vinifera L. cultivars, E. comes was largely absent, and 97–100% of leafhoppers collected were 2 cryptic species, E. bistrata McAtee and E. vitifex Fitch. On the native American variety ‘Elvira’, a V. labrusca X V riparia Michaux hybrid, field populations were 24% E. comes and 74% the E. bistrata/vitifex complex. E. vitis (Harris), E. tricinta Fitch, and E. vulnerata Fitch were also present in commercial grapes, but never exceeded 20% of the populations sampled. Populations on wild V. riparia adjacent to vineyards were comprised of 24% E. comes , 47% E. histrata/vitifex , 19% E. vitis , and 10% E. tricinta . Dissection revealed that proportions of E. bistrata and E. vitifex in field collections, varied from 97% E. bistrata to 61% E. vitifex . Oviposition of E. comes and E. bistrata on V. vinifera , interspecific hybrid, and native American cultivars was compared in greenhouse choice tests and field no-choice tests. In choice tests, E. comes laid more eggs on Concord and Elvira than on the interspecific hybrid ‘Seyval blanc’, or the V. vinifera cultivar ‘White Riesling’. E. bistrata did not oviposit on Concord when paired with either Elvira, Seyval blanc or White Riesling. When caged to grape leaves in no-choice tests, E. comes laid the most eggs on native American cultivars and the fewest on V. vinifera and interspecific hybrids; E. bistrata laid the most eggs on hybrid and V. vinifera cultivars, and very few eggs on three native American cultivars. These results show that E. bistrata and E. vitifex are the principal pest species on V. vinifera and many interspecific hybrid cultivars in New York, and that E. comes is the principal leafhopper pest on native American V. labrusca cultivars.
Houston Wilson - One of the best experts on this subject based on the ideXlab platform.
-
host plant associations of anagrus spp hymenoptera mymaridae and Erythroneura elegantula hemiptera cicadellidae in northern california
Environmental Entomology, 2016Co-Authors: Houston Wilson, Albie Miles, Kent M. DaaneAbstract:Anagrus Erythroneurae S. Trjapitzin & Chiappini and Anagrus daanei Triapitsyn are the key parasitoids of the western grape leafhopper ( Erythroneura elegantula Osborn) in northern California vineyards. Erythroneura elegantula overwinters as an adult in reproductive diapause. To successfully overwinter, Anagrus spp. must locate an alternate leafhopper host that overwinters in an egg stage that they can parasitize. These alternate leafhopper hosts are thought to be primarily located in the natural habitats surrounding vineyards. This study identifies the noncrop host plants utilized by Anagrus spp. not only during the overwintering period but throughout the entire year, as well as the leafhopper species associated with these host plants. Over a 2-yr period, Anagrus spp. and leafhoppers were sampled from numerous plants in natural and cultivated habitats surrounding vineyards. Results from this study confirm previously known Anagrus spp. host plants, but also identify new host plant species. Some of the host plants harbored Anagrus spp. year-round while others were utilized only during certain periods of the year. Leafhoppers associated with Anagrus spp. host plants may potentially serve as the alternate host utilized by Anagrus spp. on these plants, but this was not confirmed in the current study. Records of E. elegantula demonstrate their cyclical movement between the vineyard floor (winter), temporary noncrop hosts (spring/fall), and the grape vine canopy (summer).
-
vineyard proximity to riparian habitat influences western grape leafhopper Erythroneura elegantula osborn populations
Agriculture Ecosystems & Environment, 2015Co-Authors: Houston Wilson, Albie Miles, Kent M. Daane, Miguel A AltieriAbstract:The purpose of this study was to evaluate the impact of vineyard proximity to riparian habitat on the biological control and population densities of the Western grape leafhopper, Erythroneura elegantula Osborn (Hemiptera: Cicadellidae). Natural enemy and pest populations were monitored over a two-year period at multiple vineyard sites adjacent to riparian habitat in northern California. At each site, natural enemy and pest population data were collected along a transect that extended from the riparian habitat into the vineyard. Additionally, a subset of the original research sites were further evaluated for crop vigor, pest density and parasitism rates between the vineyard edge and interior. Results from this study indicate that lower E. elegantula egg deposition and nymph abundance at the vineyard edge were primarily due to reduced crop vigor at the sampled sites and that the most likely cause for these changes were differences in microclimate and soil fertility that were found to be associated with proximity to the riparian habitat.
Kent M. Daane - One of the best experts on this subject based on the ideXlab platform.
-
host plant associations of anagrus spp hymenoptera mymaridae and Erythroneura elegantula hemiptera cicadellidae in northern california
Environmental Entomology, 2016Co-Authors: Houston Wilson, Albie Miles, Kent M. DaaneAbstract:Anagrus Erythroneurae S. Trjapitzin & Chiappini and Anagrus daanei Triapitsyn are the key parasitoids of the western grape leafhopper ( Erythroneura elegantula Osborn) in northern California vineyards. Erythroneura elegantula overwinters as an adult in reproductive diapause. To successfully overwinter, Anagrus spp. must locate an alternate leafhopper host that overwinters in an egg stage that they can parasitize. These alternate leafhopper hosts are thought to be primarily located in the natural habitats surrounding vineyards. This study identifies the noncrop host plants utilized by Anagrus spp. not only during the overwintering period but throughout the entire year, as well as the leafhopper species associated with these host plants. Over a 2-yr period, Anagrus spp. and leafhoppers were sampled from numerous plants in natural and cultivated habitats surrounding vineyards. Results from this study confirm previously known Anagrus spp. host plants, but also identify new host plant species. Some of the host plants harbored Anagrus spp. year-round while others were utilized only during certain periods of the year. Leafhoppers associated with Anagrus spp. host plants may potentially serve as the alternate host utilized by Anagrus spp. on these plants, but this was not confirmed in the current study. Records of E. elegantula demonstrate their cyclical movement between the vineyard floor (winter), temporary noncrop hosts (spring/fall), and the grape vine canopy (summer).
-
vineyard proximity to riparian habitat influences western grape leafhopper Erythroneura elegantula osborn populations
Agriculture Ecosystems & Environment, 2015Co-Authors: Houston Wilson, Albie Miles, Kent M. Daane, Miguel A AltieriAbstract:The purpose of this study was to evaluate the impact of vineyard proximity to riparian habitat on the biological control and population densities of the Western grape leafhopper, Erythroneura elegantula Osborn (Hemiptera: Cicadellidae). Natural enemy and pest populations were monitored over a two-year period at multiple vineyard sites adjacent to riparian habitat in northern California. At each site, natural enemy and pest population data were collected along a transect that extended from the riparian habitat into the vineyard. Additionally, a subset of the original research sites were further evaluated for crop vigor, pest density and parasitism rates between the vineyard edge and interior. Results from this study indicate that lower E. elegantula egg deposition and nymph abundance at the vineyard edge were primarily due to reduced crop vigor at the sampled sites and that the most likely cause for these changes were differences in microclimate and soil fertility that were found to be associated with proximity to the riparian habitat.
-
spider and leafhopper Erythroneura spp response to vineyard ground cover
Environmental Entomology, 2003Co-Authors: Michael J Costello, Kent M. DaaneAbstract:Ground cover is used in some vineyards to improve soil structure and help manage insect pests; previous studies have shown lower leafhopper (Erythroneura spp.) densities on vines grown with ground cover. We undertook a 2-yr study to determine why ground cover is associated with reduced leafhopper densities. Ground cover consisted of a fall-planted cover crop of purple vetch (Vicia benghalensis) and barley (Hordeum vulgare), which senesced in May and was replaced by a complex of resident vegetation comprised primarily of the grasses Echinochloa spp., Digitaria sanguinalis, and Setaria spp., as well as common knotweed (Polygonum aviculare). We compared three treatments during the growing season: Cover, No Cover, and Cover/Exclusion. Cover/Exclusion was similar to Cover treatment but with barriers to impede arthropod movement between ground cover and vines. We measured leafhopper density and egg parasitism, spider density and diversity, and grapevine vigor, and found that mid- and late-season leafhopper densities were significantly lower in Cover versus No Cover. Neither leafhopper egg parasitism nor spider density on the vines or ground cover could explain these differences; however, grapevine vigor was significantly lower in Cover than No Cover, and provides the best correlation to leafhopper density. Late-season leafhopper density was highest in the Exclusion treatment but cannot be explained by changes in grapevine vigor. Individual spider species composition and density on the grapevine canopy varied significantly among treatments: Trachelas pacificus (Chamberlin and Ivie) was higher in the Cover treatment, Hololena nedra Chamberlin and Ivie, Cheiracanthium inclusum (Hentz), and Neoscona oaxacensis (Keyserling) were lower in the Exclusion treatment, and Oxyopes spp. was higher in the Exclusion treatment. We suggest the lower densities of leafhoppers in the Cover treatment resulted from poorer host plant quality because of the competition between ground cover and grapevines. The higher late-season leafhopper densities in the Exclusion treatment may be due to changes in spider species composition, and subsequently, differences in rates of predation on leafhopper nymphs.
R H Beamer - One of the best experts on this subject based on the ideXlab platform.
-
NEW SPECIES OF Erythroneura (HOMOPTERA-CICADELLIDAE)
Canadian Entomologist, 2020Co-Authors: R H BeamerAbstract:Color pattern: Strikingly cross-banded throughout. Vertex, white or suffused wit11 yellow. Anterior two-thirds of pronotum, orange-red ; posterior third, white. First tegminal band occupying bases of tegmina to a point on costal margin slightly caudad of tip of scutellum, deep orange-red. Second band, white, extending to middle of clavus Third band, dark orange-red, about as wide as length of costal plaque; connected narrowly along costal margin with first tegminal band. Fourth band, white; rather narrow. Fifth band, golden yellow; somewhat wider than the fourth in middle; much wider at costal margin; margins uneven. Sixth band, white or transparent; narrower than the fifth; extending almost to cross-veins. Seventh band, smoky black; occupying rest of tegmina. Cross-veins, whitish ; most of base of cell M4, transparent ; costal plaque, purplish red with a white spot in either end; dorsum of abdomen and most of ventral surface, black or dark brown with the exception of the face between the eyes which shades off into a bright red band marked by several small white spots.
-
SOME Erythroneura (GRAPE LEAF HOPPERS) OF THE MACULATA GROUP (HOMOPTERA, CICADELLIDAE)
The Canadian Entomologist, 2020Co-Authors: R H BeamerAbstract:An effort has been made in the preceding pages to present all the species of Erythroneura that have been described in the Maculata Group as well as a large number of new species. The scutelleris Group is included also because it was found they could not easily be separated on the external characters as given by other writers and the genitalia showed close relation to the Maculata Group. No doubt other species will be found as more intensive collecting is done in various parts of the country.
-
SOME Erythroneura (GRAPE LEAF HOPPERS) OF THE MACULATA GROUP. (HOMOPTERA, CICADELLIDAE)
The Canadian Entomologist, 2020Co-Authors: R H BeamerAbstract:The genus Erythroneura was divided by W. L.. McAtee and later confirmed by Wm. Robinson, into several groups by the venation of the front wing. The maculata group was characterized particularly by the absence of the M-Cu cross-vein and by the base of cell M4 being angulate. In dissecting and studying the male genitalia of several hundred specimens of this group a good many undescribed forms have been found. It is the purpose of the present paper to begin a study of the entire group, redescribing named species wliere necessary and adding the new forms. Drawings and photographs have been made but will be published later.
-
SOME Erythroneura (GRAPE LEAF HOPPERS) OF THE MACULATA GROUP. (HOMOPTERA CICADELLIDAE)
The Canadian Entomologist, 2020Co-Authors: R H BeamerAbstract:General ground color semihyaline to white, marked with orange. Vertex with semblance of five white spots more or less surrounded with orange bands. Median white spot usually elongated and with very thin median orange line. Pronotum with median elongated spot often touuching posterior margin, usual angular spot back of each eye.
-
SOME Erythroneura (GRAPE LEAF HOPPERS) OF THE MACULATA GROUP. (HOMOPTERA CICADELLIDAE)
The Canadian Entomologist, 2020Co-Authors: R H BeamerAbstract:General ground color yellowish white to semihyaline. Color markings red or orange. Veitex with semblance of white spots surrounded with red, heavier red spot on tip. Pronotum with median, rather small, triangular spot with U-shaped anterior margin and usual angular spots back of each eye. Scutellum with spot on tip, basal angles yellow with red dash on exterior margin of each anterior corner. Clavi with usual red basal anchor-shaped mark, often broken in middle, and quite long dash near tip.
Albie Miles - One of the best experts on this subject based on the ideXlab platform.
-
host plant associations of anagrus spp hymenoptera mymaridae and Erythroneura elegantula hemiptera cicadellidae in northern california
Environmental Entomology, 2016Co-Authors: Houston Wilson, Albie Miles, Kent M. DaaneAbstract:Anagrus Erythroneurae S. Trjapitzin & Chiappini and Anagrus daanei Triapitsyn are the key parasitoids of the western grape leafhopper ( Erythroneura elegantula Osborn) in northern California vineyards. Erythroneura elegantula overwinters as an adult in reproductive diapause. To successfully overwinter, Anagrus spp. must locate an alternate leafhopper host that overwinters in an egg stage that they can parasitize. These alternate leafhopper hosts are thought to be primarily located in the natural habitats surrounding vineyards. This study identifies the noncrop host plants utilized by Anagrus spp. not only during the overwintering period but throughout the entire year, as well as the leafhopper species associated with these host plants. Over a 2-yr period, Anagrus spp. and leafhoppers were sampled from numerous plants in natural and cultivated habitats surrounding vineyards. Results from this study confirm previously known Anagrus spp. host plants, but also identify new host plant species. Some of the host plants harbored Anagrus spp. year-round while others were utilized only during certain periods of the year. Leafhoppers associated with Anagrus spp. host plants may potentially serve as the alternate host utilized by Anagrus spp. on these plants, but this was not confirmed in the current study. Records of E. elegantula demonstrate their cyclical movement between the vineyard floor (winter), temporary noncrop hosts (spring/fall), and the grape vine canopy (summer).
-
vineyard proximity to riparian habitat influences western grape leafhopper Erythroneura elegantula osborn populations
Agriculture Ecosystems & Environment, 2015Co-Authors: Houston Wilson, Albie Miles, Kent M. Daane, Miguel A AltieriAbstract:The purpose of this study was to evaluate the impact of vineyard proximity to riparian habitat on the biological control and population densities of the Western grape leafhopper, Erythroneura elegantula Osborn (Hemiptera: Cicadellidae). Natural enemy and pest populations were monitored over a two-year period at multiple vineyard sites adjacent to riparian habitat in northern California. At each site, natural enemy and pest population data were collected along a transect that extended from the riparian habitat into the vineyard. Additionally, a subset of the original research sites were further evaluated for crop vigor, pest density and parasitism rates between the vineyard edge and interior. Results from this study indicate that lower E. elegantula egg deposition and nymph abundance at the vineyard edge were primarily due to reduced crop vigor at the sampled sites and that the most likely cause for these changes were differences in microclimate and soil fertility that were found to be associated with proximity to the riparian habitat.