Research

11 pages, 1533 KiB

Open AccessArticle

Taxonomic Description of Stenodiplosis tectori n. sp. (Diptera: Cecidomyiidae), a Seed Parasite of Cheatgrass, Anisantha tectorum, Based on Morphological and Mitochondrial DNA Data

by Brian G. Rector, Raymond J. Gagné, Juan Manuel Perilla López, Kirk C. Tonkel, Marie-Claude Bon, Fatiha Guermache and Massimo Cristofaro

Insects 2021, 12(8), 755; https://doi.org/10.3390/insects12080755 - 22 Aug 2021

Cited by 1 | Viewed by 1932

Abstract

Cheatgrass is an annual grass species from Eurasia that has become invasive in much of western North America. It has been implicated in recent increases in the frequency, size, and intensity of wildfires, contributing to severe economic, environmental, and social destruction. In order [...] Read more.

Cheatgrass is an annual grass species from Eurasia that has become invasive in much of western North America. It has been implicated in recent increases in the frequency, size, and intensity of wildfires, contributing to severe economic, environmental, and social destruction. In order to reduce this damage, the USDA-ARS established a classical biological control program against cheatgrass. In 2018 and 2019, adult gall midges were collected emerging from cheatgrass seed heads collected at several sites in Bulgaria and Greece; this is the first gall midge ever recorded from cheatgrass. Morphological comparisons with related midge species recorded from other plant hosts revealed that this midge from cheatgrass is a new species, described here as Stenodiplosis tectori n. sp. This status was supported by sequence comparisons of a barcode region of the gene encoding the mitochondrial cytochrome c subunit I (CO1) protein in Stenodiplosis tectori n. sp. and three congeners. The present study is the first to report MT-CO1 data in the genus Stenodiplosis. The ingroup Stenodiplosis tectori n. sp. collected in the Balkans grouped in one phylogenetic supported clade, with an average K2P-distance from its closest related congener, S. sorghicola, of 7.73% (SD = 1.10). The findings indicated relatively high year-to-year within-population diversity. Implications for this gall midge’s utility as a biological control agent of cheatgrass are discussed. Full article

(This article belongs to the Special Issue Biological Control of Invasive Plants Using Arthropods)

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14 pages, 849 KiB

Open AccessArticle

Host Specificity and Preliminary Impact of Lepidapion argentatum (Coleoptera, Brentidae), a Biocontrol Candidate for French Broom (Genista monspessulana, Fabaceae)

by Elven Kerdellant, Thierry Thomann, Andy Sheppard and René F. H. Sforza

Insects 2021, 12(8), 691; https://doi.org/10.3390/insects12080691 - 31 Jul 2021

Cited by 1 | Viewed by 1889

Abstract

French broom (Genista monspessulana) (Fabaceae) is a perennial species native to the Mediterranean basin. Introduced in the 19th century as an ornamental plant, it is currently invasive in California and Australia. The current research is focused on biocontrol with the use [...] Read more.

French broom (Genista monspessulana) (Fabaceae) is a perennial species native to the Mediterranean basin. Introduced in the 19th century as an ornamental plant, it is currently invasive in California and Australia. The current research is focused on biocontrol with the use of the phytophagous weevil Lepidapion argentatum (Brentidae). Its capacity to develop both in the stem galls and pods of French broom makes it a promising candidate. The impact on the reproduction of French broom was studied in Southern France and revealed that it could effectively reduce the number of viable seeds by 18.8%, but also increased the number of aborted seeds by 10% within the attacked pods. To evaluate the specificity of L. argentatum, choice and no-choice tests were performed in 2012 and 2015 on a total of 36 non-target closely related species. Results revealed the presence of galls and larvae in the stems of seven species, including two endemic Californian lupines; i.e., Lupinus arboreus blue and Lupinus chamissonis. In the future, new tests will be conducted to determine if L. argentatum is able to complete its entire development lifecycle on the non-target species where galls have previously been observed. Full article

(This article belongs to the Special Issue Biological Control of Invasive Plants Using Arthropods)

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16 pages, 2845 KiB

Open AccessArticle

Field Assessment of the Host Range of Aculus mosoniensis (Acari: Eriophyidae), a Biological Control Agent of the Tree of Heaven (Ailanthus altissima)

by Francesca Marini, Erica Profeta, Biljana Vidović, Radmila Petanović, Enrico de Lillo, Philip Weyl, Hariet L. Hinz, Chandra E. Moffat, Marie-Claude Bon, Tatjana Cvrković, Javid Kashefi, René F. H. Sforza and Massimo Cristofaro

Insects 2021, 12(7), 637; https://doi.org/10.3390/insects12070637 - 13 Jul 2021

Cited by 7 | Viewed by 2938

Abstract

Tree of heaven (Ailanthus altissima) is a fast-growing deciduous tree native to China, considered a serious invasive species worldwide, with several socio-economic and ecological impacts attributed to it. Chemical and mechanical methods have limited efficacy in its management, and biological controls [...] Read more.

Tree of heaven (Ailanthus altissima) is a fast-growing deciduous tree native to China, considered a serious invasive species worldwide, with several socio-economic and ecological impacts attributed to it. Chemical and mechanical methods have limited efficacy in its management, and biological controls may offer a suitable and sustainable option. Aculus mosoniensis (Ripka) is an eriophyid mite that has been recorded to attack tree of heaven in 13 European countries. This study aims to explore the host range of this mite by exposing 13 plant species, selected either for their phylogenetic and ecological similarity to the target weed or their economic importance. Shortly after inoculation with the mite, we recorded a quick decrease in mite number on all nontarget species and no sign of mite reproduction. Whereas, after just one month, the population of mites on tree of heaven numbered in the thousands, irrespective of the starting population, and included both adults and juveniles. Significantly, we observed evidence of damage due to the mite only on target plants. Due to the specificity, strong impact on the target, and the ability to increase its population to high levels in a relatively short amount of time, we find A. mosoniensis to be a very promising candidate for the biological control of tree of heaven. Full article

(This article belongs to the Special Issue Biological Control of Invasive Plants Using Arthropods)

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16 pages, 2322 KiB

Open AccessArticle

Evaluation of the Impact of Eustenopus villosus on Centaurea solstitialis Seed Production in California

by Michael J. Pitcairn, Dale M. Woods, Donald B. Joley and Charles E. Turner

Insects 2021, 12(7), 606; https://doi.org/10.3390/insects12070606 - 02 Jul 2021

Cited by 1 | Viewed by 1442

Abstract

The impact of the capitulum weevil Eustenopus villosus on Centaurea solstitialis seed production was examined at two field sites in central California. The study occurred in 1993–1995 during the early phases of the biological control program on C. solstitialis and before the current [...] Read more.

The impact of the capitulum weevil Eustenopus villosus on Centaurea solstitialis seed production was examined at two field sites in central California. The study occurred in 1993–1995 during the early phases of the biological control program on C. solstitialis and before the current guild of capitulum insects had become widespread. Results showed that adult feeding on early flower buds resulted in 60–70% of buds failing to develop. Regrowth delayed capitulum production by 9 days and extended production by 4 weeks at season end. Between 69% and 92% of capitula were punctured from feeding or oviposition but the occurrence of larvae in capitula ranged from 27% to 49%. Seed production in C. solstitialis capitula increased linearly with size. The occurrence of larvae was proportionally higher in larger capitula (>8 mm) but the probability of attack for individual capitula did not vary with plant size. Total seed loss from larval feeding ranged from 34 to 47%. It is recommended that another survey be performed to determine if the level of infestation of E. villosus has increased since its initial introduction. Full article

(This article belongs to the Special Issue Biological Control of Invasive Plants Using Arthropods)

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19 pages, 3268 KiB

Open AccessEditor’s ChoiceArticle

Biology of an Adventive Population of the Armored Scale Rhizaspidiotus donacis, a Biological Control Agent of Arundo donax in California

by Charles A. Braman, Adam M. Lambert, A. Zeynep Özsoy, Ellen N. Hollstien, Kirsten A. Sheehy, Tara McKinnon, Patrick Moran, John F. Gaskin, John A. Goolsby and Thomas L. Dudley

Insects 2021, 12(7), 588; https://doi.org/10.3390/insects12070588 - 29 Jun 2021

Cited by 2 | Viewed by 2435

Abstract

Arundo donax (giant reed) is invasive in Mediterranean, sub-, and tropical riparian systems worldwide. The armored scale Rhizaspidiotus donacis is approved for biocontrol in North America, but an adventive population was recently discovered in southern California. We documented this population’s distribution, phylogeny, phenology, [...] Read more.

Arundo donax (giant reed) is invasive in Mediterranean, sub-, and tropical riparian systems worldwide. The armored scale Rhizaspidiotus donacis is approved for biocontrol in North America, but an adventive population was recently discovered in southern California. We documented this population’s distribution, phylogeny, phenology, potential host spillover to Phragmites spp., and potential for parasitism by a common biocontrol parasitoid of citrus scale. The adventive scale was found within a single watershed and is genetically closest to Iberian scale genotypes. Rhizaspidiotus donacis developed on Phragmites haplotypes but at much lower densities than Arundo. The adventive population is univoltine, producing crawlers from March-June. Aphytis melinus parasitoids exhibited sustained interest in R. donacis during choice and no-choice trials and oviposition resulted in a small second generation. Rhizaspidiotus donacis appears limited in distribution by its univoltinism and sessile adult females. This presents challenges for broad biocontrol implementation but allows for targeted application. The genetic differentiation between imported biocontrol samples and adventive populations presents an opportunity for exploring benefits of hybrids and/or alternative genotypes where establishment has been difficult. While unlikely to occur in situ, spillover to vulnerable endemic Phragmites or deleterious parasitoid effects on scale biocontrol agents warrants consideration when planning use of R. donacis. Full article

(This article belongs to the Special Issue Biological Control of Invasive Plants Using Arthropods)

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11 pages, 392 KiB

Open AccessArticle

Biological and Host Range Characteristics of Lysathia flavipes (Coleoptera: Chrysomelidae), a Candidate Biological Control Agent of Invasive Ludwigia spp. (Onagraceae) in the USA

by Angelica M. Reddy, Paul D. Pratt, Brenda J. Grewell, Nathan E. Harms, Ximena Cibils-Stewart, Guillermo Cabrera Walsh and Ana Faltlhauser

Insects 2021, 12(5), 471; https://doi.org/10.3390/insects12050471 - 19 May 2021

Cited by 2 | Viewed by 2297

Abstract

Exotic water primroses (Ludwigia spp.) are aggressive invaders in aquatic ecosystems worldwide. To date, management of exotic Ludwigia spp. has been limited to physical and chemical control methods. Biological control provides an alternative approach for the management of invasive Ludwigia spp. but [...] Read more.

Exotic water primroses (Ludwigia spp.) are aggressive invaders in aquatic ecosystems worldwide. To date, management of exotic Ludwigia spp. has been limited to physical and chemical control methods. Biological control provides an alternative approach for the management of invasive Ludwigia spp. but little is known regarding the natural enemies of these exotic plants. Herein the biology and host range of Lysathia flavipes (Boheman), a herbivorous beetle associated with Ludwigia spp. in Argentina and Uruguay, was studied to determine its suitability as a biocontrol agent for multiple closely related target weeds in the USA. The beetle matures from egg to adult in 19.9 ± 1.4 days at 25 °C; females lived 86.3 ± 35.6 days and laid 1510.6 ± 543.4 eggs over their lifespans. No-choice development and oviposition tests were conducted using four Ludwigia species and seven native plant species. Lysathia flavipes showed little discrimination between plant species: larvae aggressively fed and completed development, and the resulting females (F1 generation) oviposited viable eggs on most plant species regardless of origin. These results indicate that L. flavipes is not sufficiently host-specific for further consideration as a biocontrol agent of exotic Ludwigia spp. in the USA and further testing is not warranted. Full article

(This article belongs to the Special Issue Biological Control of Invasive Plants Using Arthropods)

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12 pages, 251 KiB

Open AccessArticle

The Host Range of the Stem-Boring Weevil, Listronotus setosipennis (Coleoptera: Curculionidae) Proposed for the Biological Control of Parthenium hysterophorus (Asteraceae) in Pakistan

by Philip Sebastian Richard Weyl, Abdul Rehman and Kazam Ali

Insects 2021, 12(5), 463; https://doi.org/10.3390/insects12050463 - 17 May 2021

Cited by 4 | Viewed by 2970 | Correction

Abstract

Parthenium, or Parthenium hysterophorus, has extended its range in Pakistan throughout Punjab and into Khyber Pakhtunkhwa, the Federally Administrated Tribal Areas, Azad Jammu and Kashmir, and Sindh Provinces. Without control measures against parthenium, the negative impacts of this weed will go unchecked [...] Read more.

Parthenium, or Parthenium hysterophorus, has extended its range in Pakistan throughout Punjab and into Khyber Pakhtunkhwa, the Federally Administrated Tribal Areas, Azad Jammu and Kashmir, and Sindh Provinces. Without control measures against parthenium, the negative impacts of this weed will go unchecked having deleterious effects on native biodiversity, human and animal health, as well as crop productivity. The weevil Listronotus setosipennis was obtained and imported from the Plant Health and Protection of the Agricultural Research Council (ARC-PHP), in Cedara, South Africa, in April 2019. A total of 22 plant species or cultivars in the Asteraceae family were assessed during no-choice oviposition tests in Pakistan. During these tests, the only plant species accepted for oviposition were the 10 cultivars of Helianthus annuus that are grown in Pakistan. All cultivars were thus tested for development of L. setosipennis from egg to adult. Only three cultivars were able to support some larval development, but at such low levels that it is unlikely to be the basis of a viable population. To support this, a risk assessment was conducted to ascertain the probability of L. setosipennis being able to sustain viable populations in the field, the results of which concur with native (Argentina) and introduced (Australia) field host-range information where L. setosipennis has never been recorded as a pest of sunflowers. The results of laboratory-based host-range trials, together with host records from its native and introduced range, indicate that L. setosipennis is sufficiently specific to parthenium and is thus suitable for release in Pakistan. Full article

(This article belongs to the Special Issue Biological Control of Invasive Plants Using Arthropods)

22 pages, 1516 KiB

Open AccessArticle

Host Range and Impact of Dichrorampha aeratana, the First Potential Biological Control Agent for Leucanthemum vulgare in North America and Australia

by Sonja Stutz, Rosemarie De Clerck-Floate, Hariet L. Hinz, Alec McClay, Andrew J. McConnachie and Urs Schaffner

Insects 2021, 12(5), 438; https://doi.org/10.3390/insects12050438 - 12 May 2021

Cited by 2 | Viewed by 1978

Abstract

We evaluated the potential of the European root-feeding moth Dichrorampha aeratana as a biological control agent for the invasive weed Leucanthemum vulgare (oxeye daisy) in North America and Australia. The taxonomic proximity of the ornamental Shasta daisy (Leucanthemum × superbum) to [...] Read more.

We evaluated the potential of the European root-feeding moth Dichrorampha aeratana as a biological control agent for the invasive weed Leucanthemum vulgare (oxeye daisy) in North America and Australia. The taxonomic proximity of the ornamental Shasta daisy (Leucanthemum × superbum) to L. vulgare and its popularity in North America made finding sufficiently host-specific biological control agents a challenge. No-choice tests conducted with 74 non-target species revealed partial or complete larval development on 11 species. In multiple-choice oviposition and larval development tests that were conducted in field cages, larvae were found on five of these, however in multiple-choice tests conducted under open-field conditions, larvae were only found on the ornamentals Shasta daisy and creeping daisy (Mauranthemum paludosum). Larval feeding by D. aeratana had no measurable impact on Shasta daisy, but larval feeding and plant competition reduced the biomass and number of flower heads of L. vulgare. We conclude that D. aeratana is a suitable biological control agent because it will not affect the ornamental value of Shasta or creeping daisies and because it is unlikely to feed on any other economically important or native species. We also expect D. aeratana to contribute to the suppression of L. vulgare populations. Full article

(This article belongs to the Special Issue Biological Control of Invasive Plants Using Arthropods)

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Review

Jump to: Research, Other

16 pages, 2318 KiB

Open AccessEditor’s ChoiceReview

Using Chemical Ecology to Enhance Weed Biological Control

by Alexander M. Gaffke, Hans T. Alborn, Tom L. Dudley and Dan W. Bean

Insects 2021, 12(8), 695; https://doi.org/10.3390/insects12080695 - 03 Aug 2021

Cited by 9 | Viewed by 3220

Abstract

In agricultural systems, chemical ecology and the use of semiochemicals have become critical components of integrated pest management. The categories of semiochemicals that have been used include sex pheromones, aggregation pheromones, and plant volatile compounds used as attractants as well as repellents. In [...] Read more.

In agricultural systems, chemical ecology and the use of semiochemicals have become critical components of integrated pest management. The categories of semiochemicals that have been used include sex pheromones, aggregation pheromones, and plant volatile compounds used as attractants as well as repellents. In contrast, semiochemicals are rarely utilized for management of insects used in weed biological control. Here, we advocate for the benefit of chemical ecology principles in the implementation of weed biocontrol by describing successful utilization of semiochemicals for release, monitoring and manipulation of weed biocontrol agent populations. The potential for more widespread adoption and successful implementation of semiochemicals justifies multidisciplinary collaborations and increased research on how semiochemicals and chemical ecology can enhance weed biocontrol programs. Full article

(This article belongs to the Special Issue Biological Control of Invasive Plants Using Arthropods)

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22 pages, 1276 KiB

Open AccessReview

Climate Mismatch between Introduced Biological Control Agents and Their Invasive Host Plants: Improving Biological Control of Tropical Weeds in Temperate Regions

by Nathan E. Harms, Ian A. Knight, Paul D. Pratt, Angelica M. Reddy, Abhishek Mukherjee, Ping Gong, Julie Coetzee, S. Raghu and Rodrigo Diaz

Insects 2021, 12(6), 549; https://doi.org/10.3390/insects12060549 - 12 Jun 2021

Cited by 21 | Viewed by 4962

Abstract

Many weed biological control programs suffer from large-scale spatial variation in success due to restricted distributions or abundances of agents in temperate climates. For some of the world’s worst aquatic weeds, agents are established but overwintering conditions limit their survival in higher latitudes [...] Read more.

Many weed biological control programs suffer from large-scale spatial variation in success due to restricted distributions or abundances of agents in temperate climates. For some of the world’s worst aquatic weeds, agents are established but overwintering conditions limit their survival in higher latitudes or elevations. The resulting need is for new or improved site- or region-specific biological control tools. Here, we review this challenge with a focus on low-temperature limitations of agents and propose a roadmap for improving success. Investigations across spatial scales, from global (e.g., foreign exploration), to local (selective breeding), to individual organisms (molecular modification), are discussed. A combination of traditional (foreign) and non-traditional (introduced range) exploration may lead to the discovery and development of better-adapted agent genotypes. A multivariate approach using ecologically relevant metrics to quantify and compare cold tolerance among agent populations is likely required. These data can be used to inform environmental niche modeling combined with mechanistic modeling of species’ fundamental climate niches and life histories to predict where, when, and at what abundance agents will occur. Finally, synthetic and systems biology approaches in conjunction with advanced modern genomics, gene silencing and gene editing technologies may be used to identify and alter the expression of genes enhancing cold tolerance, but this technology in the context of weed biological control has not been fully explored. Full article

(This article belongs to the Special Issue Biological Control of Invasive Plants Using Arthropods)

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25 pages, 820 KiB

Open AccessReview

Eriophyid Mites in Classical Biological Control of Weeds: Progress and Challenges

by Francesca Marini, Philip Weyl, Biljana Vidović, Radmila Petanović, Jeffrey Littlefield, Sauro Simoni, Enrico de Lillo, Massimo Cristofaro and Lincoln Smith

Insects 2021, 12(6), 513; https://doi.org/10.3390/insects12060513 - 01 Jun 2021

Cited by 9 | Viewed by 4059

Abstract

A classical biological control agent is an exotic host-specific natural enemy, which is intentionally introduced to obtain long-term control of an alien invasive species. Among the arthropods considered for this role, eriophyid mites are likely to possess the main attributes required: host specificity, [...] Read more.

A classical biological control agent is an exotic host-specific natural enemy, which is intentionally introduced to obtain long-term control of an alien invasive species. Among the arthropods considered for this role, eriophyid mites are likely to possess the main attributes required: host specificity, efficacy, and long-lasting effects. However, so far, only a few species have been approved for release. Due to their microscopic size and the general lack of knowledge regarding their biology and behavior, working with eriophyids is particularly challenging. Furthermore, mites disperse in wind, and little is known about biotic and abiotic constraints to their population growth. All these aspects pose challenges that, if not properly dealt with, can make it particularly difficult to evaluate eriophyids as prospective biological control agents and jeopardize the general success of control programs. We identified some of the critical aspects of working with eriophyids in classical biological control of weeds and focused on how they have been or may be addressed. In particular, we analyzed the importance of accurate mite identification, the difficulties faced in the evaluation of their host specificity, risk assessment of nontarget species, their impact on the weed, and the final steps of mite release and post-release monitoring. Full article

(This article belongs to the Special Issue Biological Control of Invasive Plants Using Arthropods)

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