Vitacea Polistiformis Research Articles

Subterranean Acoustic Activity Patterns of Vitacea polistiformis (Lepidoptera: Sesiidae) in Relation to Abiotic and Biotic Factors.

Grape root borer (GRB), Vitacea polistiformis, is a root-feeding pest of grapevines in the US southeast that causes underground damage well before vines show visible symptoms. A 269-d study was conducted at 31 sites in a Florida vineyard to record short bursts of insect movement and feeding vibrations in grapevine root systems and provide information that can improve timing and targeting of GRB management efforts. Characteristic spectral and temporal patterns in the subterranean vibrations facilitated discrimination of GRB from background noise and non-targeted arthropods. Infestation likelihood of GRB at each site was estimated from previous studies relating infestation to burst rate. In all, 39% of recordings indicated low infestation likelihood. Sites with medium or high infestation likelihood were confined to a small region of the vineyard where a vine with larval feeding damage was confirmed. The restricted area suggests that the biological control or chemical treatments could be reduced elsewhere. Acoustic activity was significantly greater in fall and winter than in spring, and greater in evening than afternoon; fall evenings seemed best for GRB acoustic surveys. The GRB seasonal and circadian acoustic variation reflected phenological variation in grape root growth and nutrients and was not significantly correlated with temperature.

Grape Root Borer Pest Management in Florida Vineyards

The most important insect pest of grapes in Florida is the grape root borer, Vitacea polistiformis (Harris), a sesiid moth. The grape root borer (GRB) is native to the eastern United States, and ranges south of a line from Vermont across to Minnesota and east of the Mississippi River states, and occurs throughout peninsular Florida. Grape root borer have been damaging vineyards in the southeastern U.S. for over 150 years. It has been declared the most destructive insect pest of grapes in many states including Georgia, North Carolina, and Florida. This document is Fact Sheet ENY-831, a series of the Entomology and Nematology Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Publication date: July 2005.

Relative captures of grape root borer, Vitacea polistiformis (Lepidoptera: Sesiidae) in pheromone traps within vineyards and adjacent woodlands

The grape root borer (GRB), Vitacea polistiformis (Harris), is a significant pest of grapes (Vitis spp.) throughout parts of the eastern United States. Early detection and implementation of management tactics can prevent economic losses and vine death. The establishment of an effective monitoring program requires the deployment of pheromone baited traps in vineyards and native wild grapes. An understanding of the spatial distribution of GRB infestations is critical for the development of sampling plans and for implementing management decisions. Wing traps baited with synthetic GRB sex pheromones (99:1 blend of (E,Z)-2,13-ODDA and Z,Z-3,13-ODDA) were deployed in commercial vineyards and surrounding woodlands in wild grapes to monitor GRB abundance and distribution. In addition, pheromone-baited wing traps were placed at low, medium, and high positions (0.5 m–2 m above the ground) on the grapevine trellis in commercial vineyards to evaluate the effect of trap height on the number of GRB captured. Traps placed in the cultivated vineyard had consistently higher counts of GRB compared with traps along the vineyard edge and in the wild grapes in the woodland. The pheromone-baited traps placed on the highest trellis wire caught more GRB adults than traps placed at the lowest position on the bottom trellis wire. Therefore, we recommend to place traps at approximately 2 m in the upper grapevine canopy early in the season before flight of GRB moth begins in order to aid in the timing and implementation of management tactics.

Food-Finding Capability of Grape Root Borer (Lepidoptera: Sesiidae) Neonates in Soil Column Bioassays

Abstract Grape root borer, Vitacea polistiformis (Harris), is an economically important and potentially destructive pest of grape vines in portions of the eastern United States. Its oligophagous larvae feed on the roots of cultivated and wild Vitis species. In commercial vineyards, adult females oviposit on aboveground parts of vines and other vegetation in vine rows. The loosely attached eggs are thought to drop to the ground and, upon eclosion, neonates quickly burrow into the soil to search for grape roots. Although vineyard infestation by grape root borer is ultimately dependent upon larval success at finding and establishing on vine roots, little is known about larval movement capabilities in the soil. In this study, soil column bioassays were used to evaluate neonate movement in the horizontal and vertical dimensions, the influence of grape root stimuli on the rate and frequency of food-finding, and the distance over which the neonates responded to these stimuli. Grape root borer neonates moved bot...

Biological Control of Grape Root Borer (Lepidoptera: Sesiidae) with Commercially Available Entomopathogenic Nematodes in Florida Muscadine and ‘Cynthiana' Grapes

The grape root borer, Vitacea polistiformis (Harris) (Lepidoptera: Sesiidae), is a clearwing moth species native to the eastern United States. Its range extends north to Michigan, west to the Mississippi Valley, and south to Florida. It is a major pest of grapes in the eastern United States, damaging vines by girdling the roots, thus cutting off nutrients and water transfer from the roots to the remainder of the plant. A single larva feeding on the root system is able to reduce a vine’s yield by 50%, and two or three larvae within a root system can reduce winter hardiness, fruit quality, and yield and can ultimately destroy an entire vine (Dutcher and All 1979, J. Econ. Entomol. 72: 159–161). Adult grape root borers do not feed and they live for about 8 d (Dutcher and All 1978, J. Georgia Entomol. Soc. 13: 59–63). Females lay their eggs on or near grape vines and nearby weeds, and the eggs fall to the soil surface where they hatch approximately 18 d later. Younger larvae feed throughout the entire root zone while older larvae are concentrated at the trunk. Most researchers agree that the borer’s life cycle takes 2 yr to complete and that it overwinters in the larval stage, which lasts for up to 22 mo. Pupation occurs near the soil surface in June and July (Dutcher and All 1979). Weihman and Liburd (2007, Florida Entomol. 89: 245–250), however, postulate that there is a 2-yr life cycle in the East but that populations in Florida may have a 1-yr cycle, with adults emerging over a period of 6 mo compared to the 2-mo period farther north. Natural enemies, resistant root stocks, and insecticides offer some management of the grape root borer. Other pest-management strategies include mating disruption (Johnson et al. 1981, Misc. Publ. Entomol. Soc. Ark. 12(2):1–7; Johnson

Effects of biotic and abiotic factors on grape root borer (Lepidoptera: Sesiidae) infestations in commercial vineyards in Virginia.

Larval grape root borer, Vitacea polistiformis (Harris) (Lepidoptera: Sesiidae), feed on roots of wild Vitis and commercially important Vitis species and rootstocks in portions of the eastern United States. Grape root borer pupal exuviae sampling in Virginia vineyards from 2008 to 2012 revealed that infestation levels varied substantially among 48 vineyard blocks. Data on horticultural (cultivar, rootstock, vine age, and planting area), cultural (insecticide use, ground cover, weed control, and irrigation), and environmental variables (proximity to forest, soil composition, soil moisture holding capacity, pH, organic matter, bulk density, and cation exchange capacity) from each block were subjected to optimal quantification using categorical principal component analysis (CATPCA). Variables with component loading values ≥0.70 from the CATPCA were used as predictors and pupal exuviae density as the dependent variable in binary logistic regression. A prediction model was developed by including statistically significant variables in the logistic regression. CATPCA showed that seven vineyard factors (ground cover, soil texture, soil mass moisture, soil pH, clay/sand ratio, clay/silt ratio, and sand/silt ratio) based on three selected principal components were significant for subsequent regression analysis. Binary logistic regression showed that soil mass moisture and clay/sand ratio were statistically significant factors contributing to differences in infestation among vineyard blocks. Based on these two factors, a risk prediction model for calculating the probability of grape root borer infestation in vineyards was developed and validated using receiver operating characteristic curve. Results are discussed in relation to the practical implications of a predictive, risk assessment model for grape root borer management.

Spatial Distribution of Grape Root Borer (Lepidoptera: Sesiidae) Infestations in Virginia Vineyards and Implications for Sampling

Grape root borer, Vitacea polistiformis (Harris) (Lepidoptera: Sesiidae) is a potentially destructive pest of grape vines, Vitis spp. in the eastern United States. After feeding on grape roots for ≍2 yr in Virginia, larvae pupate beneath the soil surface around the vine base. Adults emerge during July and August, leaving empty pupal exuviae on or protruding from the soil. Weekly collections of pupal exuviae from an ≍1-m-diameter weed-free zone around the base of a grid of sample vines in Virginia vineyards were conducted in July and August, 2008-2012, and their distribution was characterized using both nonspatial (dispersion) and spatial techniques. Taylor's power law showed a significant aggregation of pupal exuviae, based on data from 19 vineyard blocks. Combined use of geostatistical and Spatial Analysis by Distance IndicEs methods indicated evidence of an aggregated pupal exuviae distribution pattern in seven of the nine blocks used for those analyses. Grape root borer pupal exuviae exhibited spatial dependency within a mean distance of 8.8 m, based on the range values of best-fitted variograms. Interpolated and clustering index-based infestation distribution maps were developed to show the spatial pattern of the insect within the vineyard blocks. The temporal distribution of pupal exuviae showed that the majority of moths emerged during the 3-wk period spanning the third week of July and the first week of August. The spatial distribution of grape root borer pupal exuviae was used in combination with temporal moth emergence patterns to develop a quantitative and efficient sampling scheme to assess infestations.

Behavioral Response of Grape Root Borer (Lepidoptera: Sesiidae) Neonates to Grape Root Volatiles

Grape root borer, Vitacea polistiformis (Harris), is an oligophagous and potentially destructive pest of grape in commercial vineyards throughout much of the eastern United States. Larvae feed on vine roots, although little is known about their below-ground interactions with host plants. The behavioral response of groups of grape root borer neonates to stimuli from host and nonhost roots was evaluated in single and paired stimuli bioassays in which stimuli were presented in opposing wells attached to the bottom of petri dish arenas. Stimulus sources included root pieces and root headspace volatiles from 3309 and 420-A grape rootstocks (host) and apple (nonhost) and ethanol-based extracts of 3309 and 420-A roots. In single stimulus assays, significantly more larvae were recovered from wells containing grape roots, apple roots, grape extracts, and grape root volatiles than from control wells, but there was no significant response to volatiles collected from the headspace of apple roots. In paired stimuli assays, significantly more larvae were recovered from wells containing grape than apple roots. There was no difference in larval distribution between wells when 420-A and 3309 roots were presented simultaneously, although a significantly greater response to 3309 than 420-A root extract was recorded. When soil was added to the assays, significantly more larvae were recovered from wells containing grape roots than from those containing only soil, but this response was not detected in assays using buried apple roots. These results are discussed in relation to the plant-insect interactions between grape root borer larvae and their Vitaceae hosts.

LURES, MATING DISRUPTION AND MASS TRAPPING OF THE GRAPE ROOT BORER

LURES, MATING DISRUPTION AND MASS TRAPPING OF THE GRAPE ROOT BORER

Response of Grape Root Borer (Lepidoptera: Sesiidae) Neonates to Root Extracts From Vitaceae Species and Rootstocks

Observations at regular intervals of the location of newly hatched grape root borer, Vitacea polistiformis (Harris), larvae moving freely within circular petri dish bioassays were used to measure and compare their response to dry filter paper discs treated with ethanol- or hexane-based extracts of roots from known and potential Vitaceae hosts and a nonhost. Larvae responded most strongly to discs treated with ethanol extracts, suggesting the presence of behaviorally active, polar compounds associated with roots. In single extract bioassays comparing extract versus solvent treated discs, larvae responded positively to ethanol extracts from all Vitis species and rootstocks and Virginia creeper [Parthenocissus quinquefolia (L.) Planch.], but not to apple (Malus domestica Borkh). Paired extract bioassays, in which an extract from the commercially important 3309 rootstock was used as the standard and presented simultaneously with extracts from other root sources, revealed examples of equal, significantly weaker and significantly stronger responses to the 3309 extract. Extracts of the 420 A and V. riparia 'Gloire' rootstocks appeared to possess qualities that elicited a consistently greater response than to 3309 extract in these pair-wise comparisons. The active compounds were eluted in ethanol during a 30-min extraction; larvae responded equally to 30- and 60-min 3309 root extracts in paired extract bioassays. Larvae responded equally to extracts of 3309 roots from three spatially separate vineyards in northern Virginia. These results are discussed in relation to the subterranean, plant-insect interactions of grape root borer neonates with the numerous native and non-native Vitis species that may serve as hosts in the eastern United States.

Acoustic Detection of Arthropod Infestation of Grape Roots: Scouting for Grape Root Borer (Lepidoptera: Sesiidae)

ABSTRACT The grape root borer, Vitacea polistiformis Harris, is the principal pest of grapes (Vitis spp. L.) in Florida where chlorpyrifos is 1 of the few chemicals registered for its control. However, chlorpyrifos is not an ideal treatment because it is highly toxic to birds, fish, aquatic invertebrates, and honeybees. Also, the recommended timing of application conflicts with harvest dates. There is an effective cultural control method, known as mounding, but this method is currently cost prohibitive for commercial production and is not widely used. If mounding could be applied only to infested plants, the cost of this method would be reduced considerably. This study evaluated the potential of acoustics for detecting the larvae in-situ. Human listeners assessed likelihood of arthropod infestation for each site based on live acoustic samples as they were being recorded. Computer software later constructed acoustic indicators from these recordings that were used for computer assessment of infestation like...

Applications and Mechanisms of Wax-Based Semiochemical Dispenser Technology for Disruption of Grape Root Borer Mating

Grape root borer, Vitacea polistiformis (Harris) (Lepidoptera: Sesiidae), is an important pest of cultivated grapes (Vitis spp.) in the eastern United States from Michigan to Florida. There are few registered insecticides for control of this pest, and their efficacy is limited. Pheromone-based mating disruption is a potential alternative to insecticides for management of V. polistiformis. Wax-based Specialized Pheromone & Lure Application Technology (SPLAT) was tested as a mating disruption method. Deployment densities of 150 dispensers per ha dosed with 5 mg of V. polistiformis pheromone were sufficient to achieve 95% mating disruption during a 7-wk trapping period. The disruption mechanism was determined to be competitive attraction. The release rate of pheromone from these dispensers was quantified to be approximately linear, 77.4 microg/g SPLAT/d. At this release rate, a minimum initial load of 5.4 mg of pheromone per dispenser would be needed to maintain disruption over a 9-10-wk V. polistiformis flight season, approximately 19 August to 21 October in central Florida. It should be noted, however, that the main pheromone component alone, (E,Z)-2,13-octadecadienyl acetate (ODDA), was effective (presumably by a noncompetitive mechanism) at higher loads per area of crop. Due to the cost of synthesis of highly pure isomers of the V. polistiformis pheromone components, mating disruption of V. polistiformis may be more practical with higher doses of commercially produced Zeuzera pyrina L. blend [95% (E,Z)-2,13-ODDA:5% (E,Z)-3,13-octadecadien-1-ol] or with (E,Z)-2,13-ODDA alone than with the V. polistiformis blend at lower rates.

Field efficacy against the grape root borer Vitacea polistiformis (Lepidoptera: Sesiidae) and persistence of Heterorhabditis zealandica and H. bacteriophora (Nematoda: Heterorhabditidae) in vineyards

Field efficacy and persistence of Heterorhabditis zealandica strain X1 and Heterorhabditis bacteriophora strain GPS11 applied at different times for the control of the grape root borer, Vitacea polistiformis were evaluated from 2001 to 2003 in two vineyards in Ohio and one in Georgia and from 2005 to 2007 in two vineyards in Ohio. Pheromone trapping and pupal case surveys were used to confirm the presence of borers in the vineyards. Nematode applications were targeted at the larval stages of the grape root borer. Percent control based on the number of emerging adults in Ohio ranged from 55% to 92% and in Georgia from 55% to 78%. Overall no significant differences were found in the numbers or timings of nematode application indicating effective control of all GRB instars and a broad window of opportunity for the application of nematodes. The ability of H. zealandica to persist in the soil profile for a period of 1 year was minimal in Ohio and none in Georgia. In contrast, H. bacteriophora persistence in Ohio was positive for all treatments up to 1 year post-treatment and in one case up to 21 months post-treatment. These studies demonstrate the potential of H. bacteriophora strain GPS11 for long-term conservation approach in vineyards for the management of the grape root borer.

GRAPE ROOT BORER CONTROL WITH NEMATODES, 2008

GRAPE ROOT BORER CONTROL WITH NEMATODES, 2008

Effect of Trap Color on Captures of Grape Root Borer (Lepidoptera: Sesiidae) Males and Non-Target Insects

Abstract The effect of bucket trap color on grape root borer (GRB), Vitacea polistiformis Harris, captures was evaluated in 2005 and 2006. Traps were deployed in a commercial vineyard consisting of muscadine (Vitis rotundifolia Michx) grapes in North-Central Florida. Experimental designs were randomized complete block with four tratments including green, yellow, white and blue traps in 2005. In 2006, five treatments (green, yellow, green top, yellow top, and multicolor) and four replicates were evaluated. All traps were baited with GRB female sex pheromone. Trap color had a significant effect on the number of GRB males captured. In 2005, green and yellow traps caught more GRB males than other trap colors. In addition, first GRB male captures were in yellow and green traps. In 2006, the multicolor trap caught more GRB males than any other trap and had the first GRB capture. Grape root borer males prefer green and yellow pheromone-baited traps, but do not appear to distinguish between these two colors, whic...

GRAPE ROOT BORER CONTROL WITH NEMATODES, 2007

GRAPE ROOT BORER CONTROL WITH NEMATODES, 2007

SEASONAL DISTRIBUTION AND EVALUATION OF TWO TRAP TYPES FOR MONITORING GRAPE ROOT BORER VITACEA POLISTIFORMIS (LEPIDOPTERA: SESIIDAE) IN FLORIDA VINEYARDS

Abstract Sixteen vineyards from 4 grape-growing regions across Florida were evaluated for seasonal distribution and presence of grape root borer (GRB), Vitacea polistiformis Harris (Lepidoptera: Sesiidae), during 2003 and 2004. Vineyards consisted of both muscadine (Vitis rotundifolia Michx.) and bunch grapes (Euvitis spp.). Grape root borer males were caught in all vineyards with Universal Moth Traps baited with female GRB pheromones, with higher captures in the northern and southern counties. Grape root borers began emerging in late Jun and early Jul in the Panhandle and southern regions. Emergence occurred in late Jul in the north-central region and in mid-Aug in the central region. Weekly trap catches indicated that peak GRB flights occurred during mid-to late Aug for the Panhandle region. In the north-central, central, and southern regions, peak flights occurred in the second and third week of Sep, coinciding with the period of grape harvest for muscadine grapes. The emergence period ceased with the ...

MOLECULAR DIAGNOSTICS OF ECONOMICALLY IMPORTANT CLEARWING MOTHS (LEPIDOPTERA: SESIIDAE)

Larvae of many species of Sesiidae, the clearwing moths, are important pests in commercial nurseries, urban landscapes, timber stands, vineyards, and orchards. They cause economic loss by larval boring in stems and roots of herbaceous and woody plants. Researchers and growers often monitor for the presence of economically important sesiid adults with pheromone traps. These traps often attract more than one species of Sesiidae and specimens often degrade making identification difficult or impossible. This can cause problems in monitoring programs where species-specific control programs are used. Polymerase chain reaction (PCR) was used to amplify a 606-bp region of the mitochondrial DNA cytochrome oxidase I (COI), tRNA leucine, and COII gene. This region exhibited 7.7-19.5% genetic variability among 8 species of Sesiidae. Samples were sequenced and restriction sites identified. PCR-restriction fragment length polymorphism (PCR-RFLP) analysis was conducted on 8 species of Sesiidae, Melittia satyriniformis, Paranthrene simulans, Pennisetia marginata, Synanthedon pictipes, S. exitiosa, S. scitula, S. rileyana, and Vitacea polistiformis, with 2 restriction enzymes, Dra I and Hinf I. This method is time efficient requiring less than 8 h to perform and cost efficient with each sample about $1. PCR-RFLP provides an accurate method to differentiate 8 species of adult clearwing moths commonly found in traps baited with commercially available pheromone lures.

MATING DISRUPTION AND ATTRACT-AND-KILL AS REDUCED-RISK STRATEGIES FOR CONTROL OF GRAPE ROOT BORER VITACEA POLISTIFORMIS (LEPIDOPTERA: SESIIDAE) IN FLORIDA VINEYARDS

Mating disruption and attract-and-kill (A&K) gels were evaluated for control of grape root borer (GRB), Vitacea polistiformis Harris (Lepidoptera:Sessidae), in Florida grape (Vitis sp.) vineyards. For mating disruption, pheromone twist-ties with leopard moth, Zeuzera pyrina L. (Lepidoptera: Cossidae), pheromone were placed in vines at a rate of 635 per ha. Attract-and-kill (A&K) gels containing the GRB pheromone and a pyrethrin (botanical insecticide) were applied to vine trunks at a rate of 112.5 g per hectare. These treatments were compared with chlorpyrifos (Lorsban), an organophosphate insecticide, and an untreated control in a randomized complete block design. Two wing-style sticky traps with GRB pheromone were placed in each treatment to monitor male moth activity and determine levels of trap shutdown. Complete trap shutdown occurred in the twist-tie sections for both 2003 and 2004 suggesting disruption of mating. Traps placed in the A&K and the pheromone twist-tie sections caught significantly fewer GRB than the Lorsban treatments in 2003. In 2004, significantly fewer moths were caught in the pheromone twist-tie and Lorsban treatments than the A&K and untreated controls. The differences between 2003 and 2004 for A&K treatments were due to the use of the incorrect pheromone blend in the 2004 batch of A&K. Whereas the differences in Lorsban treatments between both years may be related to residual activity of the pesticide. The economics of adopting A&K and mating disruption with twist-ties containing leopard moth pheromone is discussed. Both A&K and mating disruption with the leopard moth pheromone show promise as reduced-risk control tactics to be used in a GRB integrated pest management program and warrant further study.

Modeling intra-sexual competition in a sex pheromone system: how much can female movement affect female mating success?

Mating disruption theory predicts that high concentrations of female pheromone, and/or large numbers of release sites, should confuse males orienting to “calling” females, reduce the number of successful matings, and decrease the reproductive potential of the population. In this scenario, females are regarded as stationary point sources of pheromone. Past behavioral observations, however, have shown virgin female grape root borers, Vitacea polistiformis Harris, significantly alter their behavior in mating disruption treatments. Treated females call at different heights, move less before call initiation, and move more after call initiation than control females. Pheromone gland dragging and wing fanning also increase significantly during pheromone treatments. These behavioral differences are significant only if they alter the mating success of females. Because long-term field studies are impractical, we used known behavior of male and female GRB to build a Fortran language time step model, adding the effects of female movement to past models of male pheromone plume following. Females were distributed randomly, and then assigned a conditional movement strategy. If females were within the competitive portion of another female's plume, the downwind female moved. Except in the lowest population density tested, females moving upwind and crosswind when in a competing female's pheromone plume mated significantly more often than females remaining stationary. In all population simulations, mating success was significantly reduced when females moved downwind. These field and simulation studies provide strong evidence for female movement as a previously overlooked potential mechanism for resistance to mating disruption treatments, as well as a shaping behavior in the evolution of pheromone communication systems.