Epitrix Fuscula Research Articles

Solanum carolinense L.

<i>Solanum carolinense</i> L.

The Suppressive Effects of Biochar on Above- and Belowground Plant Pathogens and Pests: A Review.

Soilborne pathogens and pests in agroecosystems are serious problems that limit crop yields. In line with the development of more ecologically sustainable agriculture, the possibility of using biochar to control pests has been increasingly investigated in recent years. This work provides a general overview of disease and pest suppression using biochar. We present an updated view of the literature from 2015 to 2022 based on 61 articles, including 117 experimental case studies. We evaluated how different biochar production feedstocks, pyrolysis temperatures, application rates, and the pathosystems studied affected disease and pest incidence. Fungal pathogens accounted for 55% of the case studies, followed by bacteria (15%), insects and nematodes (8%), oomycetes and viruses (6%), and only 2% parasitic plants. The most commonly studied belowground pathogen species were Fusarium oxysporum f. sp. radicis lycopersici in fungi, Ralstonia solanacearum in bacteria, and Phytophthora capisci in oomycetes, while the most commonly studied pest species were Meloidogyne incognita in nematodes, Epitrix fuscula in insects, and both Phelipanche aegyptiaca and Orobanche crenata in parasitic plants. Biochar showed suppression efficiencies of 86% for fungi, 100% for oomycetes, 100% for viruses, 96% for bacteria, and 50% for nematodes. Biochar was able to potentially control 20 fungal, 8 bacterial, and 2 viral plant pathogens covered by our review. Most studies used an application rate between 1% and 3%, a pyrolysis temperature between 500 °C and 600 °C, and a feedstock based on sawdust and wood waste. Several mechanisms have been proposed to explain disease suppression by biochar, including induction of systemic resistance, enhancement of rhizosphere competence of the microbial community, and sorption of phytotoxic compounds of plant and/or microbial origin. Overall, it is important to standardize biochar feedstock and the rate of application to improve the beneficial effects on plants in terms of disease control.

Evaluation of OMRI and Reduced-Risk Insecticides for Control of Eggplant Flea Beetle in Eggplant, 2019

Evaluation of OMRI and Reduced-Risk Insecticides for Control of Eggplant Flea Beetle in Eggplant, 2019

Flea Beetle (Coleoptera: Chrysomelidae) Populations, Effects of Feeding Injury, and Efficacy of Insecticide Treatments on Eggplant and Cabbage in Southwest Virginia.

Flea beetles, are common pests of cabbage Brassica oleracea L. (Brassicales: Brassicaceae) and eggplant Solanum melongena L. (Solanales: Solanaceae), but little is known about the flea beetle populations in Virginia, their impact on yield, or the most effective control methods. This research investigates flea beetle populations and the impact of their feeding injury on cabbage and eggplant in Southwest Virginia and determines the most efficacious control methods. In Whitethorne, VA, cabbage and eggplant crops were vacuum sampled weekly throughout two summers (2015, 2016). Crucifer flea beetle, Phyllotreta cruciferae (Goeze) (Coleoptera: Chrysomelidae), and striped flea beetle, Phyllotreta striolata Fabr. (Coleoptera: Chrysomelidae) were found on cabbage; whereas, eggplant flea beetle, Epitrix fucula (Crotch) (Coleoptera: Chrysomelidae), and the tobacco flea beetle, Epitrix hirtipennis (Melsheimer) (Coleoptera: Chrysomelidae) were found on eggplant. To evaluate the impact of flea beetle feeding on these plants flea beetle densities and defoliation were assessed weekly and individual plant, as well as whole plot yields, assessed at harvest. For cabbage, significant yield reductions were observed between 1 and 20% and >60% defoliation. Similarly, significant yield reductions were observed between 41 and 60% and >60% defoliation for eggplant. The efficacy of various insecticides was also evaluated. Soil application of the systemic neonicotinoid dinotefuran, imidacloprid, and the foliar-applied bifenthrin resulted in the fewest beetles, the least amount of leaf defoliation, and the highest yield in cabbage and eggplant. This research helps vegetable growers to better understand the severity of these pests and how to effectively combat them.

Amendment of a hardwood biochar with compost tea: effects on plant growth, insect damage and the functional diversity of soil microbial communities

Biochar is an organic soil amendment that has been shown to improve plant growth and increase resistance to plant diseases and insect damage in certain soils. Organic growers have been known to use compost teas to amend biochar, claiming that this practice adds nutrients and beneficial microorganisms that can improve plant growth and resistance to pathogens and insect pests. However, few data exist to support this hypothesis. This study investigated the effects of a hardwood biochar amended with different types of compost teas and microbial enrichments (prepared from vermicompost) on eggplant (Solanum melongena var. Rosa Bianca) growth, flea beetle (Epitrix fuscula) damage, and soil microbial activity and functional diversity in two temperate soils. No positive short-term effects were observed on eggplant growth or flea beetle damage when biochar amended with compost teas prepared from horse manure, mushroom compost or vermicompost were added to a temperate agricultural soil. However, a second experiment suggested that biochar amended with microbial enrichments from vermicompost tea may improve eggplant growth if matched with the physical and chemical properties of a given soils. Results from Community Level Physiological Profiling (CLPP) revealed that biochar amended with compost teas altered soil microbial activity and functional diversity differently to that of biochar alone, and that these changes corresponded with plant growth and insect damage.

Volatile emissions from the flea beetle Altica litigata (Coleoptera: Chrysomelidae) associated with invasive Ludwigia hexapetala

The flea beetle Altica litigata (Chrysomelidae) is an insect herbivore to plants within the families Lythraceae and Onagraceae, including ornamentals such as crape myrtle, Lagerstroemia spp. This insect is important both as a pest species and as a naturally occurring biological control agent due to its aggregate feeding behavior, which typically results in severe defoliation of the host plant. Despite the negative economic impact to ornamentals and contrary benefits as a biological control agent, there are few reports on the semiochemical communication of this family of insects. Uruguayan primrose-willow (Ludwigia hexapetala) is an invasive aquatic weed in California and serves as a host to A. litigata. To better characterize this association, the volatile emissions of A. litigata were collected while the flea beetles were: in containers by themselves, in containers with L. hexapetala leaves, in situ on L. hexapetala leaves in a growth chamber, and in situ on L. hexapetala leaves in the field. For comparison, the volatile emissions of A. litigata associated with two subspecies of creeping water primrose (L. peploides) were also evaluated. Two himachalene-type sesquiterpenes, showing the same carbon skeleton as compounds previously reported from Aphthona flava and Epitrix fuscula, were detected as volatiles from A. litigata.

Laboratory Toxicity Profile of an Organic Formulation of Spinosad against the Eggplant Flea Beetle, Epitrix Fuscula Crotch

The eggplant flea beetle, Epitrix fuscula Crotch, is a major insect pest of eggplant, Solanum melongena L. var. esculentum (Solanaceae), produced in the south central United States and often requires management with insecticides immediately following setting of transplants into the field. Few insecticides approved for use in organic production have provided effective management of the beetles. The study reported herein demonstrates the effectiveness of Entrust, a new organic approved formulation of spinosad. Following exposure on eggplant foliage, Entrust was shown to be toxic to adult flea beetles with LC50 and LC95 values of 42.9 and 296.7 ppm, respectively. Although mortality following exposure was sometimes delayed until six days, the effects on flea beetle behavior were observed in as little as six hours following exposure. Feeding was significantly reduced one day after exposure to both the highest recommended field rate and to a 25% concentration of the high rate. Persistence in the field was short. No significant differences in mortality were detected for beetles transferred to treated and water-treated eggplant foliage taken three days after application. Of the insecticides approved for use in organic production, Entrust likely offers an excellent choice for management of eggplant flea beetles on eggplant.

Diffuse interactions between two herbivores and constraints on the evolution of resistance in horsenettle (Solanum carolinense)

Interactions between plants and herbivores are considered “diffuse” if the ecological interactions between two species, or their evolutionary responses, differ depending on the presence of a third species. I looked for evidence of diffuse interactions among horsenettle (Solanum carolinense) and two common herbivores. Plants experimentally protected from lace bugs (Gargaphia solani) were twice as susceptible to attack from flea beetles (Epitrix fuscula) once transplanted into the field. Thus, the selective benefit to horsenettle of resistance against lace bugs in nature would likely be diminished by increased attack from flea beetles. Moreover, the relative rank among horsenettle genotypes for resistance against flea beetles was changed by prior exposure to lace bugs. Thus, the genetic expression of resistance to flea beetles would depend on the “lace bug environment.” By affecting selective pressures or response to selection, these sorts of diffuse interactions in a plant-herbivore community can slow the host plant’s evolution of resistance to its herbivores.

A Caging, Handling, and Bioassay Procedure for Eggplant Flea Beetle, Epitrix fuscula Crotch (Coleoptera: Chrysomelidae)

J. Agric. Urban Entomol. 27: 50–53 (2010/2011) The eggplant flea beetle, Epitrix fuscula Crotch (Coleoptera: Chrysomelidae), is a serious pest of eggplant, Solanum melongena L. var. esculentum (Solanaceae), at time of transplanting. Eggplant seedlings, both commercial and for home gardens, are grown in greenhouses and moved to the field as clos et o the local frost-free date as possible in the spring. At this stage of plant development, plants are susceptible to injury from flea beetles. In the Mid-South of the U.S.A., eggplant flea beetles overwinter as adults. Flea beetles can locate the new seedlings within hours of transplanting and begin to feed on both the upper and lower leaf surfaces (McLeod 2006). The beetles initially produce small ‘‘shot-holes’’ and as feeding continues, the small holes can coalesce into large areas of necrotic leaf tissue. Commercial and home garden eggplants often require flea beetle management with foliar applied insecticides. Without this management, heavily infested transplants can be killed. Injury is common along the edges of large commercial eggplant fields (Diaz et al. 2004). If transplants survive flea beetle attack for two or three weeks and initiate rapid growth, the eggplant flea beetle appears to have little additional impact on the plant (Sorensen & Baker 1994). Several effective insecticides are currently labeled for eggplant flea beetle management on eggplant. However, interest exists in the development of alternative insecticides, especially for the organic market. Although field testing of candidate insecticides generally provides the best information for new insecticide selection, this can be expensive and may require several seasons of testing. Laboratory bioassays can be utilized to rapidly screen new insecticides for toxicity to various insect species. This information can be used to rapidly narrow the list of insecticides for further testing in field trials. With the eggplant flea beetle, laboratory bioassays have been difficult due to a lack of an available rearing technique, the minute size of the insect, and difficulties with the jumping behavior of the flea beetle. This report describes a procedure for eggplant flea beetle collection from the field, handling, and determination of insecticide toxicity with a laboratory bioassay. The flea beetles used in the study were collected from field produced ‘‘Black Beauty’’ eggplant grown at the University of Arkansas Main Experimental 1

Analysis of 2,4,6-Nonatrienal Geometrical Isomers from Male Flea Beetles, Epitrix hirtipennis and E. fuscula

Geometrical isomers of 2,4,6-nonatrienal have been reported from a variety of food- and insect-related sources. It was discovered recently that the eggplant flea beetle, Epitrix fuscula, uses the (2 E,4 E,6 Z) and (2 E,4 E,6 E) isomers as components of its male-produced aggregation pheromone. Here, we learned that the related species, E. hirtipennis, also emits a blend of 2,4,6-nonatrienals, including isomers not previously characterized. Patterns in emission and response suggest a pheromonal function. In an effort to acquire standards to aid in identification, we found that exposing (2 E,4 E,6 E)-2,4,6-nonatrienal (or other available 2,4,6-nonatrienals) to light readily generated a mixture of six geometrical isomers. Configurations of these were determined by NMR, and chromatographic properties (GC and HPLC) were documented. On the basis of chromatographic comparison to these standards, the most abundant, new compound from E. hirtipennis was concluded to be (2 E,4 Z,6 Z)-2,4,6-nonatrienal. Minor components from both E. hirtipennis and E. fuscula were also characterized. The analytical approach given here would also be of use in the food industry, where 2,4,6-nonatrienals are important as aroma compounds.

The Herbivores of Solanum carolinense (Horsenettle) in Northern Virginia: Natural History and Damage Assessment

Abstract I studied interactions between the herbaceous weed Solanum carolinense (horsenettle) and its herbivore community in northern Virginia from 1996–2002. Thirty-two species regularly fed on the plant, including 31 insects from 6 taxonomic orders and Microtus pennsylvanicus (meadow vole). An intensive field experiment on 960 horsenettle individuals in 2001 revealed high levels of damage to all parts of the plants. Two chrysomelid beetles—Epitrix fuscula (eggplant flea beetle) and Leptinotarsa juncta (false potato beetle)—damaged leaves on nearly every plant. Roughly half of the flowers were destroyed by herbivores, with Anthonomus nigrinus (potato bud weevil) destroying 30%. Nearly three-fourths of the fruits were damaged by three species: the tephritid fly Zonosemata electa (pepper maggot), false potato beetle, and meadow vole. The weevil Trichobaris trinotata (potato stalk borer) bored in stems of 73% of the plants, and the most damaging root feeder was the moth Synanthedon rileyana (Riley's clearwi...

Male-Produced Aggregation Pheromone Compounds from the Eggplant Flea Beetle (Epitrix fuscula): Identification, Synthesis, and Field Biossays

Volatiles from the eggplant flea beetle, Epitrix fuscula Crotch (Coleoptera: Chrysomelidae), feeding on host foliage, were investigated. Six male-specific compounds were detected and were identified through the use of mass spectrometry, nuclear magnetic resonance (NMR) spectrometry, chiral and achiral gas chromatography, high-performance liquid chromatography, electrophysiology (gas chromatography-electroantennography, GC-EAD), and microchemical tests. The two most abundant of the six compounds were (2E,4E,6Z)-2,4,6-nonatrienal (1) and (2E,4E,6E)-2,4,6-nonatrienal (2). The other four compounds, present in minor amounts, were identified as himachalene sesquiterpenes; two of these, 3 and 4, were hydrocarbons and two, 5 and 6, were alcohols. All four sesquiterpenes were previously encountered from male flea beetles of Aphthona spp. and Phyllotreta cruciferae. Synthetic 1 and 2 matched the natural products by GC retention times, mass spectra, and NMR spectra. Sesquiterpenes 3-6 similarly matched synthetic standards and natural samples from the previously studied species in all ways, including chirality. Both natural and synthetic 1 and 2 gave positive GC-EAD responses, as did sesquiterpenes 3, 5, and 6. Field trials were conducted with a mixture of 1 and 2, and the baited traps were significantly more attractive than control traps to both male and female E. fuscula. The E. fuscula pheromone has potential for monitoring or controlling these pests in eggplants.

Influence of Tillage Method and Insecticide on Asian Eggplant Production

Many growers in the St. Louis metro east area in Illinois are growing a diversity of vegetable products to satisfy local market demand, including many Asian vegetables. In 2003 and 2004, an experiment was conducted at a grower location in Belleville, Ill., to evaluate the effect of tillage method (tillage vs. no-tillage) following no-tillage corn (Zea mays) and insecticide treatment (imidacloprid, carbaryl, and none) on growth and productivity of three Asian eggplant (Solanum melongena) cultivars (`Ichiban', `Little Fingers', and `Millionaire'). Regardless of cultivar, imidacloprid resulted in greater plant growth for most of the growing season, resulting in higher early and total-season yields compared to the other insecticide treatments. Flea beetle (numerous species, including Epitrix fuscula and Epitrix cucumeris) damage to eggplants can be severe during the early part of the growing season in southern Illinois, which can drastically reduce plant growth and subsequent yields. Although carbaryl was applied at 10-d intervals for most of the growing season, flea beetle damage was similar to the no insecticide treatment and resulted in significant growth reduction and yield loss compared to imidacloprid. Tillage methods did not differ (P &gt; 0.05) for Asian eggplant productivity or flea beetle damage. Cultivar performance was similar over the tillage method and insecticide treatment as no significant interactions (P &gt; 0.05) were detected. However, cultivars differed for productivity with `Millionaire' and `Ichiban' generally providing higher marketable and total yields than `Little Fingers'.

Seasonal Occurrence and Distribution of Eggplant Flea Beetle, Epitrix fuscula Crocht (Coleoptera: Chrysomelidae) on Eggplant in Arkansas

The seasonal occurrence and distribution of the eggplant flea beetle (EFB), Epitrix fuscula Crotch, were monitored on eggplant in south central Arkansas during 1997, 1998, and 1999 and northwestern Arkansas during 1998 and 1999. In south central Arkansas, average numbers of EFB/plant were 11.9, 5.2 and 1.9 in 1997, 1998 and 1999, respectively. EFB numbers per plant decreased during the study in northwestern Arkansas from 13.3 in 1998 to 7.2 in 1999. This decline in numbers of EFB may be related to hot and dry weather during the spring and early summer months of the previous year and differences in transplant dates.Mapping the distribution of the foliar feeding by EFB indicated that the highest damage ratings (4 and 5) were recorded for eggplants on the north side of the south central field. Also, damage decreased rapidly on interior plants away from the north edge. First or edge plants in rows had damage ratings of 3.9; second and third plants averaged 2.6 and 2.1, respectively; and fourth to tenth plants had values less than 2.Additional insects encountered during eggplant sampling included the Colorado potato beetle, Leptinotarsa decemlineata (Say); the green tortoise beetle, Nuzonia pallidula (Boh.); the pepper weevil, Anthonomus eugenii Cano; Euphoria sepulcralis (Fabricius); the eggplant lace bug, Gargaphia solani Heidemann; and the corn earworm, Helicoverpa zea (Boddie). With the exception of sporadic damage by the Colorado potato beetle at the southern Arkansas location, damage from these insects was low.

Toxicity, persistence, and efficacy of spinosad, chlorfenapyr, and thiamethoxam on eggplant when applied against the eggplant flea beetle (Coleoptera: Chrysomelidae).

A laboratory bioassay was developed for determining the toxicity of spinosad, chlorfenapyr, and thiamethoxam against the eggplant flea beetle, Epitrix fuscula Crotch, on eggplant foliage. Four days after initial exposure, LC50 values were 1.99, 2.50, and 0.88 ppm for spinosad, chlorfenapyr, and thiamethoxam, respectively. By dividing the recommended field rate in ppm by the LC50 value, a field toxicity ratio was determined and ranged from 13.5 for spinosad to 73.9 for thiamethoxam. The high ratios suggest that field rates for all three insecticides could likely be reduced. This was supported by field studies in 2000 in which reduced rates of spinosad and thiamethoxam significantly reduced flea beetle numbers on eggplant. Mortality produced by thiamethoxam occurred more quickly than that for the other tested materials as shown with LT50 values of 1.8, 3.0, and 3.6 and days for thiamethoxam, chlorfenapyr, and spinosad, respectively. Persistence studies indicated that while all three of the tested compounds initially produced high levels of mortality, chlorfenapyr and thiamethoxam produced 50% or greater mortality after 6 d. Our data suggest that future management strategies for E. fuscula on eggplant can be successfully altered to meet the changing needs of the producer. Spinosad was recently registered, is effective against the E. fuscula, and offers a viable alternative to carbamate and pyrethroid insecticides. Thiamethoxam and chlorfenapyr offer high levels of toxicity to E. fuscula and upon registration will offer additional effective tools for management.

Impact of two specialist insect herbivores on reproduction of horse nettle, Solanum carolinense.

The frequency of coevolution as a process of strong mutual interaction between a single plant and herbivore species has been questioned in light of more commonly observed, complex relationships between a plant and a suite of herbivore species. Despite recognition of the possibility of diffuse coevolution, relatively few studies have examined ecological responses of plants to herbivores in complex associations. We studied the impact of two specialist herbivores, the horse nettle beetle, Leptinotarsa juncta, and the eggplant flea beetle, Epitrix fuscula, on reproduction of their host, Solanum carolinense. Our study involved field and controlled-environment experimental tests of the impact on sexual and potential asexual reproduction of attack by individuals of the two herbivore species, individually and in combination. Field tests demonstrated that under normal levels of phytophagous insect attack, horse nettle plants experienced a reduction in fruit production of more than 75% compared with plants from which insects were excluded. In controlled-environment experiments using enclosure-exclosure cages, the horse nettle's two principal herbivores, the flea beetle and the horse nettle beetle, caused decreases in sexual reproduction similar to those observed in the field, and a reduction in potential asexual reproduction, represented by root biomass. Attack by each herbivore reduced the numbers of fruits produced, and root growth, when feeding in isolation. When both species were feeding together, fruit production, but not root growth, was lower than when either beetle species fed alone. Ecological interactions between horse nettle and its two primary herbivores necessary for diffuse coevolution to occur were evident from an overall analysis of the statistical interactions between the two herbivores for combined assessment of fruit and vegetative traits. For either of these traits alone, the interactions necessary to promote diffuse coevolution apparently were lacking.

Insects, Nematodes, and Pathogens Associated by Horsenettle (Solanum carolinense) in Bermudagrass (Cynodon dactylon) Pastures

Horsenettle is a deep-rooted perennial weed that cannot be easily controlled by mechanical means or by a single chemical application. A study was conducted at two sites for two consecutive years to identify biological factors that might limit its growth. Insects, nematodes, and plant pathogens were collected from horsenettle growing in bermudagrass pastures. The insects most commonly found included the Colorado potato beetle and the eggplant flea beetle. An unidentified lepidopteron, familyGelechiidae, was found at very low frequency as pupae in hollow leaf chambers constructed at the apices of flowering meristems. Infested apices bore no fruit. Seven genera of nematodes were found in the soil at both sites, but only very low numbers of lesion nematodes were recovered from horsenettle roots, and these had caused little damage. Root rot was observed under wet soil conditions on plants damaged by trampling. A downy mildew was prevalent at both sites in both years in October.

Properties and Cytopathology of a Tymovirus Isolated from Eggplant

An isometric virus measuring 28 nm was isolated from eggplant (Solanum melongena) and mechanically transmitted to several species of the families Amaranthaceae, Chenopodiaceae, Labiatae, and Solanaceae. The virus was vectored by the flea beetle, Epitrix fuscula. Ultrastructural studies showed that chloroplasts of infected plants were clustered and formed tymovirus-characteristic double memebrane-bound vesicles. In Nicotiana rustica, immunogold labeling studies showed that the largest numbers of virus particles were in the cytoplasm and vacuole of infected cells (...)

A Mechanical Measure for Controlling the Fleabeetle (Epitrix Fuscula) on Potato.1

Journal Article A Mechanical Measure for Controlling the Fleabeetle (Epitrix Fuscula) on Potato. Get access C. L. Metcalf C. L. Metcalf Ohio State University, Columbus, Ohio Search for other works by this author on: Oxford Academic PubMed Google Scholar Journal of Economic Entomology, Volume 8, Issue 2, 1 April 1915, Pages 240–241, https://doi.org/10.1093/jee/8.2.240 Published: 01 April 1915