scholarly journals INFLUENCE OF ENVIRONMENTAL FACTORS ON ENTOMOPATHOGENIC MICROORGANISMS WITH POTENTIAL AS BIOLOGICAL CONTROL AGENTS - minireview

2020 ◽  
Vol 13 ◽  
pp. 96-104
Author(s):  
Ana-Cristina Fătu ◽  
Cristina-Maria Lumînare ◽  
Daniel Cojocaru ◽  
Mihaela-Monica Dinu
Keyword(s):  
Biological Control ◽  
Environmental Factors ◽  
Insect Pests ◽  
Ecological Efficiency ◽  
Control Programs ◽  
Wide Range ◽  
Microbiological Control ◽  
Abiotic And Biotic Factors ◽  
Entomopathogenic Hyphomycetes ◽  
Number Of Authors

"The entomopathogenic fungi play an important role in suppressing the natural population of insect pests. A number of these microorganisms are developed and commercialized as mycoinsecticides for controlling arthropod pests in agriculture and forestry. A wide range of factors and the interactions between them can affect the persistence and survival of entomopathogenic microorganisms; understanding of these factors is indispensable for the successful use of microbiological control agents, in conditions of economic and ecological efficiency. The influence of some of these factors on fungal development and fate in soil and on plants has been studied by a number of authors for several entomopathogenic hyphomycetes used in biological control programs. The aim of this study was to summarize a few aspects about the abiotic and biotic factors that influence the biological activity of entomopathogenic microorganisms. The following environmental factors are presented: light, temperature and humidity, soil, microorganisms, wind and precipitation. "

scholarly journals Fatores de virulência de Bacillus thuringiensis: o que existe além das proteínas Cry

2012 ◽  
Vol 5 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Gislayne Trindade Vilas-Bôas ◽  
Rita C. Alvarez ◽  
Clelton A. Dos Santos ◽  
Laurival A. Vilas-Boas
Keyword(s):  
Biological Control ◽  
Bacillus Thuringiensis ◽  
Virulence Factors ◽  
Insect Pests ◽  
Cry Proteins ◽  
Control Programs ◽  
Wide Range ◽  
Vip Proteins ◽  
Bacterium Bacillus ◽  
And Control

As proteínas Cry produzidas pela bactéria entomopatogênica Bacillus thuringiensis Berliner são bem conhecidas devido a alta citotoxicidade que exibem a uma variedade de insetos-alvo. O modo de ação destas proteínas é específico e torna os produtos à base de B. thuringiensis os mais amplamente utilizados em programas de controle biológico de pragas na agricultura e de importantes vetores de doenças humanas. Contudo, embora as proteínas Cry sejam os fatores de virulência inseto-específico mais conhecidos, linhagens de B. thuringiensis apresentam também uma ampla gama de fatores de virulência, os quais permitem à bactéria atingir a hemolinfa e colonizar eficientemente o inseto hospedeiro. Dentre estes fatores, destacam-se as proteínas Vip, Cyt, enterotoxinas, hemolisinas, fosfolipases, proteases, enzimas de degradação, além das recentemente descritas parasporinas. Essa revisão aborda a ação desses fatores de virulência, bem como a caracterização e o controle da expressão de seus genes. Adicionalmente, são discutidos aspectos relacionados ao nicho ecológico da bactéria com ênfase nas características envolvidas com a biossegurança da utilização dos produtos à base de B. thuringiensis para o controle biológico de insetos-alvo. Virulence Factors of Bacillus thuringiensis Berliner: Something Beyond of Cry Proteins? Abstract. The Cry proteins produced by the entomopathogenic bacterium Bacillus thuringiensis Berliner are widely known due to its high toxicity against a variety of insects. The mode of action of these proteins is specific and becomes B. thuringiensis-based products the most used in biological control programs of insect pests in agriculture and of important human disease vectors. However, while the Cry proteins are the best-known insect-specific virulence factor, strains of B. thuringiensis show also a wide range of other virulence factors, which allow the bacteria to achieve the hemolymph and colonize efficiently the insect host. Among these factors, we highlight the Vip proteins, Cyt, enterotoxins, hemolysins, phospholipases, proteases and enzymes of degradation, in addition to the recently described parasporin. This review explores the action of these virulence factors, as well as, the characterization and control of expression of their genes. Additionally, we discuss aspects related to the ecological niche of the bacteria with emphasis on the characteristics involved in the biosafety of the use of B. thuringiensis-based products for biological control of target insects.

scholarly journals Multiscale Determinants Drive Parasitization of Drosophilidae by Hymenopteran Parasitoids in Agricultural Landscapes

Insects ◽  
2020 ◽  
Vol 11 (6) ◽  
pp. 334 ◽  
Author(s):  
Valeria Trivellone ◽  
Michela Meier ◽  
Corrado Cara ◽  
Lucia Pollini Paltrinieri ◽  
Felix Gugerli ◽  
...  
Keyword(s):  
Biological Control ◽  
Habitat Type ◽  
Agricultural Landscapes ◽  
Drosophila Suzukii ◽  
Control Programs ◽  
Native Parasitoids ◽  
Extensive Field ◽  
Pupal Parasitoids ◽  
Abiotic And Biotic Factors ◽  
Using Data

(1) The management of agricultural landscapes for pest suppression requires a thorough understanding of multiple determinants controlling their presence. We investigated the ecological preferences of indigenous parasitoids and their drosophilid hosts to understand the role of native parasitoids as biological control agents of the invasive frugivorous Drosophila suzukii. (2) Using data from an extensive field survey across different habitat types we analyzed the influence of abiotic and biotic factors on parasitoid and drosophilid communities at multiscale levels. (3) Eight parasitoid and 27 drosophilid species were identified. Thirty-four percent variation in drosophilid communities was explained by factors at the landscape scale, and 52% of significant variation of parasitoids by local distribution of three drosophilid species, mainly collected in woodland. Parasitoid communities were significantly influenced by microhabitat type (ground versus canopy) rather than habitat type. All parasitoids except Pachycrepoideus vindemmiae preferred the ground microhabitat. All parasitoids, with the exception of Trichopria drosophilae and Spalangia erythromera, displayed significant preferences among the drosophilid species used in the baited traps. (4) Since they can tolerate a broad range of habitat factors, altogether pupal parasitoids investigated in this study could play a role in biological control programs to suppress D. suzukii, but non-target effects have to be regarded.

Random amplified polymorphic DNA markers for DNA fingerprinting and genetic variability assessment of minute parasitic wasp species (Hymenoptera: Mymaridae and Trichogrammatidae) used in biological control programs of phytophagous insects

Genome ◽  
1993 ◽  
Vol 36 (3) ◽  
pp. 580-587 ◽  
Author(s):  
Benoit S. Landry ◽  
Louise Dextraze ◽  
Guy Boivin
Keyword(s):  
Biological Control ◽  
Dna Fingerprinting ◽  
Dna Markers ◽  
Insect Pests ◽  
Random Amplified Polymorphic Dna ◽  
Parasitic Wasp ◽  
Egg Parasitoid ◽  
Wasp Species ◽  
Control Programs ◽  
Traditional Taxonomy

Biological control of insects that feed on our crops has become more practical in recent years by mass release of egg parasitoid microhymenoptera. Trichogramma species are now commercially reared and spread in commercial fields to control specific insect pests. Microhymenoptera species are, however, very small and morphologically indistinguishable within species, although strains of a given species differ in their efficiency to control specific insect pests. Traditional taxonomy is unable to differentiate microhymenoptera species at the strain level. It is becoming increasingly important to develop a reliable system to monitor genetic variations both within and between strains of commercially important microhymenoptera, to detect genetic drift occurring during several generations of multiplication, to protect patents, and to certify the lots of commercially released microhymenoptera. We have developed a system based on DNA markers to rapidly characterize individuals of five species of microhymenoptera from the genus Anaphes and Trichogramma including a new species of Anaphes not previously described. The main components of our system are a rapid and simple DNA micro-extraction method and fast DNA polymorphism analyses based on random amplified polymorphic DNA markers.Key words: genetic mapping, population genetics, Anaphes spp., Trichogramma spp., RAPD, DNA markers, DNA fingerprinting.

scholarly journals Genetic variability among three Egyptian isolates of Heterorhabditis indica using a new marker technique (SCoT)

2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Amany M. Abd El Azim ◽  
Etr H. K. Khashaba
Keyword(s):  
Biological Control ◽  
Agricultural Soils ◽  
Insect Pests ◽  
Genetic Relationships ◽  
Its Region ◽  
Start Codon ◽  
Heterorhabditis Indica ◽  
Control Programs ◽  
Scot Marker ◽  
First Time

Abstract Background Entomopathogenic nematodes (EPNs) are a group of nematode families, have the ability to search for their hosts, and are considered as promising biological control candidates for insect pests, providing protection to non-target organisms and the environment. Results This study was conducted to isolate indigenous EPN isolates from Egyptian agricultural soils for further use in biological control programs and study their genetic polymorphism among the previously isolated isolates under accession no. MH553167 and MK300683 and the new isolate (MH496627), using the start codon targeted (SCoT) marker. One out of 15 soil samples obtained from a banana cultivated field was positive for the presence of EPNs, using the Galleria baiting method. Morphological analysis and sequencing of the internal transcribed spacer (ITS) region suggested that the isolate obtained belongs to Heterorhabditis indica. The sequence of the ITS was submitted to the National Center for Biotechnology Information (NCBI) and registered under accession no. MH496627. Ten SCoT primers were used in the study; the polymorphic bands were 68 out of 76 with 89% as polymorphism percentage. The highest numbers of bands were 10 bands generated by SCoT 1 and SCoT 18 while SCoT 48 and SCoT 60 recorded the lowest band number (5 bands). Conclusions The present study is considered as a preliminary study to demonstrate the effectiveness of the SCoT marker for the first time in assessing genetic relationships in EPNs.

scholarly journals Insect parasitoids : a Canadian perspective on their use for biological control of forest insect pests

2005 ◽  
Vol 74 (1) ◽  
pp. 51-67 ◽  
Author(s):  
S.M. Smith
Keyword(s):  
Biological Control ◽  
Natural Enemies ◽  
Native Species ◽  
Insect Pests ◽  
Forest Tree ◽  
Forest Environment ◽  
Forest Insect ◽  
New Host ◽  
Inundative Release ◽  
Control Programs

An overview of biological control programs against forest insect pests is presented with emphasis on Canadian case histories. The work is examined in the context of conservation, introduction, and augmentation (environmental manipulation and inoculative and inundative release) of insect natural enemies, specifically parasitoids. Historically, studies have concentrated on introductions of exotic parasitoids for control of introduced pests where a number of successes have been recorded. More recent work has entailed inoculative and inundative releases of parasitoids against native pests in an attempt to establish new host-parasitoid relationships to reduce pest populations. These have had limited success and are still being explored by Canadian researchers. Current strategies for using natural enemies are inundative release of native species against native pests and conservation of native parasitoids through selective insecticide timing and forest manipulation. Future directions in biological control programs will include these approaches with increased emphasis on biotechnology and the genetic selection or manipulation of 'desired strains' for release. Continued ecological studies will be essential to ensure a more complete understanding of the interaction between these 'selected parasitoids' and the forest/tree parameters which will influence their success (tri-trophic interactions). These parameters, such as tree vigour (pest resistance), spatial distribution and diversity, will also be targeted for selection to improve the effect of insect natural enemies in the forest environment.

Detection and Identification of Viruses in Economically Important Insects

2000 ◽  
Vol 6 (S2) ◽  
pp. 666-667
Author(s):  
E. L. Styer ◽  
J. J. Hamm
Keyword(s):  
Biological Control ◽  
Insect Pests ◽  
Reproductive Potential ◽  
Biological Control Agents ◽  
Control Programs ◽  
Detection And Identification ◽  
Zoo Animals ◽  
Viruslike Particles ◽  
And Behavior ◽  
Insect Viruses

Economically important insects include pests of plants, animals and stored products as well as insects produced commercially (honey bees, silkworms, insects for fish bait and food for birds and zoo animals). Other insects are produced in large numbers for experimental purposes, biological control of insect pests and weeds and the production of sterile insects for population suppression. Insect viruses may affect morphology, physiology and behavior, often reducing longevity and reproductive potential. Thus insect viruses can be used as biological control agents of pest insects. Insect viruses may also interfere with the production or function of biological control agents (e.g., parasitoids and predators) and insects used for research purposes. Therefore, it is advantageous to screen commercial and research colonies and imported insects for viruses.Electron microscopy of negatively stained specimens (NS EM) offers a relatively rapid and inexpensive means of screening populations of insects for the presence of viruses or viruslike particles and to monitor the progress of virus control programs.

scholarly journals First Report of Native Parasitoids of Halyomorpha halys (Hemiptera: Pentatomidae) in Greece

Insects ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 984
Author(s):  
Stefanos S. Andreadis ◽  
Nikoloz E. Gogolashvili ◽  
Georgios T. Fifis ◽  
Emmanouel I. Navrozidis ◽  
Thomas Thomidis
Keyword(s):  
Biological Control ◽  
Crop Production ◽  
Egg Parasitoids ◽  
Halyomorpha Halys ◽  
Green Beans ◽  
Northern Greece ◽  
Egg Masses ◽  
Control Programs ◽  
Native Parasitoids ◽  
Wide Range

Halyomorpha halys (Stål) (Hemiptera: Pentatomidae) is an endemic species of East Asia; it was introduced into Europe in 2007. It has a wide range of hosts as it feeds on over 170 host plant species and significantly impacts crop production. In Greece, H. halys causes significant losses in the production of kiwi, peaches, and green beans; thus, control of this species (including biological control) is essential. Here, we focus on the potential impact of native natural enemies of H. halys in Greece. From June to October 2020, we sampled naturally field-laid H. halys egg masses to recover native parasitoids. A total of 20 egg masses of H. halys were collected from infested fields from different locations in northern Greece. Out of 529 eggs, 45 parasitoids managed to hatch successfully. The overall parasitism rate was 8.5%. We found two species of Hymenopteran egg parasitoids attacking H. halys eggs—Anastatus bifasciatus (Geoffrey) (Hymenoptera: Eupelmidae) and Ooencyrtus telenomicida (Vassiliev) (Hymenoptera: Encyrtidae), with the former comprising 58% of all parasitoids that were recovered. These results contribute to the knowledge about the natural enemy community that attacks H. halys in Greece, and the use of these native egg parasitoids in biological control programs may be a viable H. halys management strategy.

Cost–Benefit Analysis for Biological Control Programs That Targeted Insect Pests of Eucalypts in Urban Landscapes of California

2015 ◽  
Vol 108 (6) ◽  
pp. 2497-2504 ◽  
Author(s):  
T. D. Paine ◽  
J. G. Millar ◽  
L. M. Hanks ◽  
J. Gould ◽  
Q. Wang ◽  
...  
Keyword(s):  
Biological Control ◽  
Insect Pests ◽  
Cost Benefit Analysis ◽  
Cost Benefit ◽  
Urban Landscapes ◽  
Benefit Analysis ◽  
Control Programs

scholarly journals Isolation, identification, and study of the genetic diversity between three entomopathogenic nematodes belonging to Heterorhabditis sp. using ISSR technique

2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Etr H. K. Khashaba ◽  
Amany M. A. Abd El Azim
Keyword(s):  
Genetic Diversity ◽  
Biological Control ◽  
Entomopathogenic Nematodes ◽  
Insect Pests ◽  
Its Region ◽  
Control Programs ◽  
Inter Simple Sequence Repeats ◽  
Band Number ◽  
Simple Sequence ◽  
Issr Primers

Abstract Background Entomopathogenic nematodes (EPNs) are widely used in biological control for soil-dwelling stages of many insect pests that are characterized by their safety to most non-target organisms and to the environment. Results The objectives of the present study were isolation of EPNs from agricultural soil in Egypt for further use in biological control programs and study the genetic variation among them using the molecular marker inter-simple sequence repeats (ISSR). Three out of 25 soil samples collected from fields cultivated with strawberry, tangerine, and pumpkin were positive for the presence of EPNs, using the Galleria baiting technique. Sequencing of the internal transcribed spacer (ITS) region indicated that the isolates obtained belong to Heterorhabditis sp. The ITS sequences were submitted to the National Center for Biotechnology Information (NCBI) and registered under accession nos. MH553165, MH553168, and MH553169. Six ISSR primers were used. The numbers of polymorphic bands were 42 out of 56, and the polymorphism percentage was 75%. The highest number of bands was 12 bands generated by primer ISSR8 followed by UBC-809 (11 bands) while recorded the lowest band number (4 bands), the percentage of polymorphism ranged from 40% (ISSR1) to 100% (ISSR6). Conclusion ISSR marker can be considered a good marker to study genetic diversity and detecting the genetic polymorphism among the nematodes species.

Satu Kahkonen and Anthony Lanyi. Institutions, Incentives, and Economic Reforms in India. New Delhi: Sage Publications, 2000. 516 pages. Hardback. Price Indian Rs 595.00.

2001 ◽  
Vol 40 (1) ◽  
pp. 71-74
Author(s):  
Attiya Y. Javed
Keyword(s):  
Reform Process ◽  
New Delhi ◽  
Social Rules ◽  
Reform Agenda ◽  
The Social ◽  
Wide Range ◽  
Rural Governance ◽  
Private And Public ◽  
Economic Landscape ◽  
Number Of Authors

The economic reform process began in India in 1991. However, the reform agenda is still far from its goals as is evident from low per capita income. Thus, this reform effort has not produced the desired outcome of a faster rate of economic and social development in a meaningful way. It is the premise of this volume that to transform the social and economic landscape, the proposed reforms should be broadbased and multi-pronged which take into account incentives for the stockholders in both the private and public sectors. The institutions are the rules that govern economy and include the fundamental legal, political, and social rules that establish the basis for production, exchange, and distribution. The two editors of this volume have received contributions from a number of authors and the wide range of papers are grouped under five main headings: political economy of reforms, reforming public goods delivery, reform issues in agriculture and rural governance, and reforming the district and financial sector.

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