scholarly journals Dyella-Like Bacterium Isolated from an Insect as a Potential Biocontrol Agent Against Grapevine Yellows

2018 ◽  
Vol 108 (3) ◽  
pp. 336-341 ◽  
Author(s):  
Lilach Iasur-Kruh ◽  
Tirtza Zahavi ◽  
Roni Barkai ◽  
Shiri Freilich ◽  
Einat Zchori-Fein ◽  
...  
Keyword(s):  
Fluorescent In Situ Hybridization ◽  
Biocontrol Agent ◽  
Biological Control Agent ◽  
Control Agent ◽  
Insect Vector ◽  
Plant Leaves ◽  
Disease Symptoms ◽  
Grapevine Yellows ◽  
Potential Biocontrol Agent

Yellows diseases, caused by phytopathogenic bacteria of the genus Phytoplasma, are a major threat to grapevines worldwide. Because conventional applications against this pathogen are inefficient and disease management is highly challenging, the use of beneficial bacteria has been suggested as a biocontrol solution. A Dyella-like bacterium (DLB), isolated from the Israeli insect vector of grapevine yellows (Hyalesthes obsoletus), was suggested to be an endophyte. To test this hypothesis, the bacterium was introduced by spraying the plant leaves, and it had no apparent phytotoxicity to grapevine. Fluorescent in situ hybridization analysis showed that DLB is colonizing grapevine phloem. Because phytoplasmas inhabit the same niche, DLB interactions with this phytopathogen were examined. When the isolate was introduced to phytoplasma-infected Chardonnay plantlets, morphological disease symptoms were markedly reduced. The mode of DLB action was then tested using bioinformatics and system biology tools. DLB genome analysis suggested that the ability to reduce phytoplasma symptoms is related to inhibition of the pathogenic bacterium. These results provide the first step in examining the potential of DLB as a biological control agent against phytoplasmas in grapevine and, possibly, other agricultural crops.

scholarly journals Phenotypic and molecular characterization of the causal agent of chafer beetle mortality in the wheat fields of the Kurdistan province, Iran

2015 ◽  
Vol 55 (3) ◽  
pp. 227-234 ◽  
Author(s):  
Keivan Karimi ◽  
Mahdi Arzanlou ◽  
Asadollah Babai Ahari ◽  
Mostafa Mansour Ghazi
Keyword(s):  
Field Experiments ◽  
Biocontrol Agent ◽  
Galleria Mellonella ◽  
Sequence Data ◽  
Biological Control Agent ◽  
Control Agent ◽  
Internal Transcribed Spacer Region ◽  
First Case ◽  
Potential Biocontrol Agent

AbstractWe report the first case of chafer beetle [Anisoplia austriaca(Herbst 1783)] mortality caused byActinomucor elegansvar.elegansin wheat fields of the Kurdistan province, Iran. For three years, dead larvae ofAnisoplia austriacawere collected from wheat fields of the Kurdistan province. Similar isolates of a fast-growing fungus were recovered from all samples. The fungal isolates were identified asA. elegansvar.elegansbased on morphological and cultural characteristics. The identity of the species was further confirmed using sequence data of the ITS (Internal Transcribed Spacer) region of ribosomal DNA. Koch’s postulates were fulfilled by the inoculation of the larvae ofA. austriacaandGalleria mellonella(Linnaeus, 1758) (as the model insect) using the spore suspension ofA. elegansvar.elegans. The viability of sporangiospores was evaluated using a spore dilution technique on germination medium. The results on the pathogenicity (100% mortality inA. austriacalarvae) and viability tests (germination: 95.45%) demonstrated thatA. elegansvar.eleganscan be considered as a potential biocontrol agent against the chafer beetle. Field experiments are still required to evaluate the capacity ofA. elegansas a biological control agent.

scholarly journals Cladobotryum mycophilum as Potential Biocontrol Agent

Agronomy ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 891
Author(s):  
Mila Santos ◽  
Fernando Diánez ◽  
Alejandro Moreno-Gavíra ◽  
Brenda Sánchez-Montesinos ◽  
Francisco J. Gea
Keyword(s):  
Biological Control ◽  
Fusarium Oxysporum ◽  
Biocontrol Agent ◽  
Biological Control Agent ◽  
Control Agent ◽  
Phytopathogenic Fungi ◽  
Antagonistic Activity ◽  
Dual Culture ◽  
Potential Biocontrol Agent

A study was conducted to explore the efficacy of potential biocontrol agent Cladobotryum mycophilum against different phytopathogenic fungi. The growth rates of 24 isolates of C. mycophilum were determined, and their antagonistic activity was analysed in vitro and in vivo against Botrytis cinerea, Fusarium oxysporum f. sp. radicis-lycopersici, Fusarium oxysporum f.sp. cucumerinum, Fusarium solani, Phytophthora parasitica, Phytophthora capsici, Pythium aphanidermatum and Mycosphaerella melonis. Most isolates grow rapidly, reaching the opposite end of the Petri dish within 72–96 h. Under dual-culture assays, C. mycophilum showed antagonistic activity in vitro against all phytopathogenic fungi tested, with mycelial growth inhibition ranging from 30 to 90% against all the different phytopathogens tested. Similarly, of all the selected isolates, CL60A, CL17A and CL18A significantly (p < 0.05) reduced the disease incidence and severity in the plant assays compared to the controls for the different pathosystems studied. Based on these results, we conclude that C. mycophilum can be considered as a potential biological control agent in agriculture. This is the first study of Cladobotryum mycophilum as a biological control agent for different diseases caused by highly relevant phytopathogens in horticulture.

A case of ecological specialization in ladybirds:Iberorhyzobius rondensis(Coleoptera: Coccinellidae), potential biocontrol agent ofMatsucoccus feytaudi(Hemiptera: Matsucoccidae)

2014 ◽  
Vol 104 (3) ◽  
pp. 367-375 ◽  
Author(s):  
C. Tavares ◽  
H. Jactel ◽  
I. van Halder ◽  
Z. Mendel ◽  
M. Branco
Keyword(s):  
Biological Control ◽  
Biocontrol Agent ◽  
Biological Control Agent ◽  
Classical Biological Control ◽  
Control Agent ◽  
Ecological Specialization ◽  
Egg Masses ◽  
Complete Development ◽  
The North ◽  
Potential Biocontrol Agent

AbstractSpecialization is an important attribute of a biological control agent. The maritime pine bast scale,Matsucoccus feytaudiDucasse (Hemiptera Matsucoccidae), is an invasive species in Southeast France and the North of Italy.Iberorhyzobius rondensisEizaguirre (Coleoptera: Coccinellidae), is a recently described ladybird species. Both adults and larvae are predaceous, feeding on egg masses ofM. feytaudi, and are strongly attracted toM. feytaudi’s sex pheromone. To evaluate the potential ofI. rondensisas a biocontrol agent of the scale, we studied its niche breadth and prey range with emphasis on pine forests and hemipterans as tested prey. In this study,I. rondensiswas found to achieve complete development only when fed onM. feytaudiegg masses (92.9% survival) and an artificial prey: eggs ofEphestia kuehniellaZeller (27.6% survival). From the 2nd instar onwards, complete development could be achieved using other prey species, although larvae had significantly higher mortality and slower development. In choice tests,M. feytaudiwas the preferred prey. Surveys of the ladybird populations in the Iberian Peninsula revealed that it was found exclusively onPinus pinasterAiton, the sole host ofM. feytaudi. The unusual specialization ofI. rondensis, among other predaceous ladybirds, makes it an appropriate candidate for classical biological control ofM. feytaudi.

scholarly journals Beauveria brongniartii a potential biocontrol agent for use against manuka beetle larvae damaging dairy pastures on Cape Foulwind

2010 ◽  
Vol 63 ◽  
pp. 224-228 ◽  
Author(s):  
R.J. Townsend ◽  
T.L. Nelson ◽  
T.A. Jackson
Keyword(s):  
Biocontrol Agent ◽  
Biological Control Agent ◽  
Larval Mortality ◽  
Field Trials ◽  
Control Agent ◽  
Field Application ◽  
Beauveria Brongniartii ◽  
Rate Dependent ◽  
Potential Biocontrol Agent ◽  
Selection Of

Manuka beetles (Pyronota sp; Scarabaeidae) are serious and persistent pests of dairy pastures on Cape Foulwind Westport When a selection of scarabactive fungal isolates were tested against 3rd instar larvae of two Pyronota species a locally sourced Beauveria brongniartii (F636) isolate consistently achieved the fastest and highest levels of larval mortality Topical application of F636 caused an average of 80 larval mortality 6 weeks posttreatment Mortality was shown to be dose rate dependent for both Pyronota species When treatments were applied by incorporating rice grains colonised by the fungus into soil simulating field application F636 again produced the fastest and highest levels of larval mortalities averaging 70 6 weeks postapplication Mortalities of both Pyronota species reached 100 after 8 weeks when the assay medium was a grey sand based soil (ex Cape Foulwind) Isolate F636 shows promise as a biological control agent for this pest and field trials have been carried out in the autumn of 2010

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

Insects ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 588
Author(s):  
Charles A. Braman ◽  
Adam M. Lambert ◽  
A. Zeynep Özsoy ◽  
Ellen N. Hollstien ◽  
Kirsten A. Sheehy ◽  
...  
Keyword(s):  
Biological Control ◽  
Biological Control Agent ◽  
Control Agent ◽  
Arundo Donax ◽  
Giant Reed ◽  
Aphytis Melinus ◽  
Adult Females ◽  
Armored Scale ◽  
Riparian Systems

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.

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

Insects ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 471
Author(s):  
Angelica M. Reddy ◽  
Paul D. Pratt ◽  
Brenda J. Grewell ◽  
Nathan E. Harms ◽  
Ximena Cibils-Stewart ◽  
...  
Keyword(s):  
Biological Control ◽  
Host Range ◽  
Plant Species ◽  
Biocontrol Agent ◽  
Biological Control Agent ◽  
Control Agent ◽  
Native Plant ◽  
Native Plant Species ◽  
The Usa ◽  
Physical And Chemical

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.

scholarly journals Could Gnomoniopsis castaneae Be Used as a Biological Control Agent against Insect Pests?

2021 ◽  
Vol 11 (9) ◽  
pp. 4066
Author(s):  
Spiridon Mantzoukas ◽  
Ioannis Lagogiannis ◽  
Aristeidis Ntoukas ◽  
George T. Tziros ◽  
Konstantinos Poulas ◽  
...  
Keyword(s):  
Biocontrol Agent ◽  
Insect Pests ◽  
Biological Control Agent ◽  
Brown Rot ◽  
Control Agent ◽  
Effective Control ◽  
Mortality Factor ◽  
Perennial Crop ◽  
Gall Wasp ◽  
Pathogenic Potential

Gnomoniopsis castaneae is the cause of the chestnut brown rot but has been also regarded as an important mortality factor for the chestnut gall wasp Dryocosmus kuriphilus. The question to whether G. castaneae could serve as a natural biocontrol agent against insect pests is investigated in the present study. We used three serious insect pests as experimental model insects: Plodia interpuctella and Trogoderma granarium, which are important pests of stored products, and Myzus persicae, a cosmopolitan, serious pest of annual and perennial crop plants. Although chemical pesticides represent effective control means, they are also related to several environmental and health risks. In search for alternative pest management methods, scientific interest has been focused, inter alia, on the use of entomopathogenic fungi. While Isaria fumosorosea has long been recognized as an effective control agent against several pests, G.castaneae has been very little studied. The present study examined whether and to what extent G. castaneae and I. fumosorosea exhibit insecticidal activity against fourth-instar larvae of P. interpunctella and T. granarium and adults of M. persicae. Mortality was examined in interrelation with dosage and time exposure intervals. Both fungi exhibited pesticidal action. However, G. castaneae induced noteworthy mortality only at very high doses. In general, we concluded that G. castaneae failed to cause high insect pathogenicity at normal doses and may not be an efficient biocontrol agent compared with other entomopathogens. On the other hand, our study reiterates the pathogenic potential of I. fumosorosea. More studies are needed to further our insight into the potential of EF species as a component of IPM.

scholarly journals Land-Use Effect on Olive Groves Pest Prays oleae and on Its Potential Biocontrol Agent Chrysoperla carnea

Insects ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 46
Author(s):  
João Frederico Alves ◽  
Sara Mendes ◽  
António Alves da Silva ◽  
José Paulo Sousa ◽  
Daniel Paredes
Keyword(s):  
Biological Control ◽  
Land Use ◽  
Biological Control Agent ◽  
Control Agent ◽  
Agricultural Landscapes ◽  
Chrysoperla Carnea ◽  
Land Uses ◽  
Prays Oleae ◽  
Potential Biocontrol Agent ◽  
Olive Groves

Olive growing has been intensified through the simplification of agricultural landscapes. In order to rethink the environmental drawbacks of these practices, conservation biological control techniques have been examined. In this work, Prays oleae and its natural enemy Chrysoperla carnea were monitored to account for the effects of the amount and diversity of different land-uses. We found that C. carnea showed an attraction to areas with high abundances of P. oleae but this predator did not display any affection by the different land-uses. Inversely, P. oleae abundance was lower in diverse landscapes and higher in simplified ones. Importantly, higher abundances of C. carnea were related to lower infestation levels of P. oleae in the late part of the season. These results corroborate the attraction of C. carnea to the olive moth, highlighting the potential of C. carnea as a biological control agent of this pest, assert that the promotion of land-use diversity can reduce P. oleae and confirm that landscapes dominated by olive groves can promote this pest. The present study aims at contributing to the discussion about the management of agricultural ecosystems by providing farmers with sustainable alternatives that do not have harmful effects on the environment and public health.

Evaluation ofAlternaria macrosporaas a Potential Biocontrol Agent for Spurred Anoda (Anoda cristata): Host Range Studies

Weed Science ◽  
1979 ◽  
Vol 27 (6) ◽  
pp. 612-614 ◽  
Author(s):  
H. L. Walker ◽  
G. L. Sciumbato
Keyword(s):  
Host Range ◽  
Biocontrol Agent ◽  
Disease Symptoms ◽  
Hibiscus Trionum ◽  
Potential Biocontrol Agent ◽  
Specialized Form ◽  
Hibiscus Esculentus ◽  
Sida Spinosa ◽  
Prickly Sida ◽  
Anoda Cristata

The host range of an isolate of the fungal pathogenAlternaria macrosporaZimmerman from infected spurred anoda [Anoda cristata(L.) Schlecht.] leaves was studied in the greenhouse and growth chamber. The fungus was inoculated to representative plants in the Malvaceae, Solanaceae, Leguminosae, and Gramineae families. Evidence of infection was limited to plants in the Malvaceae, with spurred anoda being the most susceptible species tested. Only negligible damage was incited on cotton (Gossypium hirsutumL. ‘Stoneville 213′) and long staple cotton (G. barbadenseL. ‘Pima S–5′), hollyhock [Althaea rosea(L.) Cav.], okra (Hibiscus esculentusL. ‘Clemson spineless’), prickly sida (Sida spinosaL.), velvetleaf (Abutilon theophrastiMedic.), and Venice mallow (Hibiscus trionumL.). Disease symptoms induced in cotton by the spurred anoda isolate ofA. macrosporawere much less severe than those reported for other isolates of the fungus. Therefore, the spurred anoda isolate may be a specialized form of the fungus.

scholarly journals Unexpected parasitism of Douglas-fir seed chalcid limits biocontrol options for invasive Douglas-fir in New Zealand

2021 ◽  
Vol 74 (1) ◽  
pp. 70-77
Author(s):  
Sonia Lee ◽  
Simon V. Fowler ◽  
Claudia Lange ◽  
Lindsay A. Smith ◽  
Alison M. Evans
Keyword(s):  
Biological Control ◽  
New Zealand ◽  
Seed Production ◽  
Biocontrol Agent ◽  
Biological Control Agent ◽  
Parasitoid Wasp ◽  
Control Agent ◽  
Douglas Fir ◽  
Seed Predator ◽  
High Level

Douglas-fir seed chalcid (DFSC) Megastigmus spermotrophus, a small (3 mm long) host-specific seed-predatory wasp, was accidentally introduced into New Zealand in the 1920s. Concern over DFSC reducing Douglas-fir seed production in New Zealand led to an attempt at biocontrol in 1955 with the release, but failed establishment, of the small (2.5 mm long) parasitoid wasp, Mesopolobus spermotrophus. We investigated why DFSC causes little destruction of Douglas-fir seed in New Zealand (usually <20%) despite the apparent absence of major natural enemies. Douglas-fir seed collections from 13 New Zealand sites yielded the seed predator (DFSC) but also potential parasitoids, which were identified using morphology and partial COI DNA sequencing. DFSC destroyed only 0.15% of Douglas-fir seed. All parasitoids were identified as the pteromalid wasp, Mes. spermotrophus, the host-specific biocontrol agent released in 1955. Total parasitism was 48.5%, but levels at some sites approached 90%, with some evidence of density-dependence. The discovery of the parasitoid Mes. spermotrophus could indicate that the biocontrol agent released in 1955 did establish after all. Alternatively, Mes. spermotrophus could have arrived accidentally in more recent importations of Douglas-fir seed. The high level of parasitism of DFSC by Mes. spermotrophus is consistent with DFSC being under successful biological control in New Zealand. Suppression of DFSC populations will benefit commercial Douglas-fir seed production in New Zealand, but it also represents the likely loss of a potential biological control agent for wilding Douglas-fir.

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