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

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.

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

Egyptian Journal of Biological Pest Control ◽

10.1186/s41938-021-00425-2 ◽

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.

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Biological Control of Tephritid Fruit Flies in the Americas and Hawaii: A Review of the Use of Parasitoids and Predators

Insects ◽

10.3390/insects11100662 ◽

2020 ◽

Vol 11 (10) ◽

pp. 662

Author(s):

Flávio R. M. Garcia ◽

Sérgio M. Ovruski ◽

Lorena Suárez ◽

Jorge Cancino ◽

Oscar E. Liburd

Keyword(s):

Biological Control ◽

Fruit Fly ◽

Fruit Flies ◽

Economic Importance ◽

Parasitoid Species ◽

Control Programs ◽

First Time ◽

Tephritid Fruit Flies

Biological control has been the most commonly researched control tactic within fruit fly management programs. For the first time, a review is carried out covering parasitoids and predators of fruit flies (Tephritidae) from the Americas and Hawaii, presenting the main biological control programs in this region. In this work, 31 species of fruit flies of economic importance are considered in the genera Anastrepha (11), Rhagoletis (14), Bactrocera (4), Ceratitis (1), and Zeugodacus (1). In this study, a total of 79 parasitoid species of fruit flies of economic importance are listed and, from these, 50 are native and 29 are introduced. A total of 56 species of fruit fly predators occur in the Americas and Hawaii.

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Genetic diversity analysis of Iranian Nigella sativa L. landraces using SCoT markers and evaluation of adjusted polymorphism information content

Plant Genetic Resources ◽

10.1017/s1479262115000386 ◽

2015 ◽

Vol 15 (1) ◽

pp. 64-71 ◽

Cited By ~ 4

Author(s):

Khaled Mirzaei ◽

Ghader Mirzaghaderi

Keyword(s):

Genetic Diversity ◽

Information Content ◽

Polymorphism Information Content ◽

Nigella Sativa ◽

Genetic Relationships ◽

Start Codon ◽

Discrimination Power ◽

Black Cumin ◽

Scot Marker ◽

Mediterranean Regions

The genetic diversity of 39 Iranian black cumin (Nigella sativa L.) landraces was analysed using 14 polymorphic Start Codon Targeted (SCoT) markers. A total of 106 bands ranging from 3 (for SCoT70) to 13 (for SCoT23) were observed. Of them, 33 (31%) bands were polymorphic with a mean of 1.65 bands per primer. Polymorphism information content (PIC) per primer ranged from 0.035 (for SCoT12) to 0.133 (for SCoT70), with an average of 0.078. Besides PIC, Simpson's diversity (D) index was also calculated for each SCoT marker as an indication of discrimination power across population. The D index was used to adjust the PIC of the SCoT markers. As the adjusted PIC (PICD= PIC × D) was calculated based on both the PIC and the rate of band dispersion, this reflected the informativeness of a dominant marker more precisely than PIC. Genetic relationships were estimated using Jaccard's similarity coefficient-generated values between different pairs of genotypes that varied from 80 to 97% with an average of 88%. These coefficients were applied to construct a dendrogram using the UPGMA algorithm. A high genetic similarity was observed that might be due to the fact that N. sativa is a self-pollinated plant not originated from Iran and might have been imported from the Mediterranean regions.

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

EntomoBrasilis ◽

10.12741/ebrasilis.v5i1.146 ◽

2012 ◽

Vol 5 (1) ◽

pp. 1-10 ◽

Cited By ~ 4

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.

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Natural enemies of armored scales (Hemiptera: Diaspididae) and soft scales (Hemiptera: Coccoidae) in Chile: molecular and morphological identification

10.1101/429357 ◽

2018 ◽

Author(s):

P. Amouroux ◽

D. Crochard ◽

M.C.G. Correa ◽

G. Groussier ◽

P. Kreiter ◽

...

Keyword(s):

Biological Control ◽

Natural Enemies ◽

Ornamental Plants ◽

Integrative Taxonomy ◽

Scale Insects ◽

Morphological Identification ◽

Correct Identification ◽

Predator Species ◽

Control Programs ◽

First Time

AbstractScale insects (Hemiptera: Coccoidea) are key pests of agricultural crops and ornamental plants worldwide. Their populations are difficult to control, even with insecticides, due to their cryptic habits. Moreover, there is growing concern over the use of synthetic pesticides for their control, due to deleterious environmental effects and the emergence of resistant populations of target pests. In this context, biological control may be an effective and sustainable approach. Hymenoptera Chalcidoidea includes natural enemies of scale insects that have been successfully used in many biological control programs. However, the correct identification of pest scale species and their natural enemies is particularly challenging because these insects are very small and highly specialized. Integrative taxonomy, coupling DNA barcoding and morphological analysis, has been successfully used to characterize pests and natural enemy species. In this study, we performed a survey of parasitoids and predators of armored and soft scales in Chile, based on 28S and COI barcodes. Fifty-three populations of Diaspididae and 79 populations of Coccidae were sampled over the entire length of the country, from Arica (18°S) to Frutillar (41°S), between January 2015 and February 2016. The phylogenetic relationships obtained by Bayesian inference from multilocus haplotypes revealed 40 putative species of Chalcidoidea, five Coccinellidae and three Neuroptera. In Chalcidoidea, 22 species were identified morphologically, resulting in new COI barcodes for 12 species and new 28S barcodes for 14 species. Two predator species (Rhyzobius lophantae and Coccidophilus transandinus) were identified morphologically, and two parasitoid species, Chartocerus niger and Signiphora bifasciata, were recorded for the first time in Chile.

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Report of A Larval Parasitoid of Tuta Absoluta (Meyrick) (Lepidoptera: Gelechiidae) from Iran

Journal of Plant Protection Research ◽

10.2478/jppr-2014-0046 ◽

2014 ◽

Vol 54 (3) ◽

pp. 306-307 ◽

Cited By ~ 4

Author(s):

Fariba Sohrabi ◽

Hossein Lotfalizadeh ◽

Hoda Salehipour

Keyword(s):

Biological Control ◽

Natural Enemies ◽

Tuta Absoluta ◽

Parasitoid Species ◽

Tomato Leafminer ◽

Control Programs ◽

Larval Parasitoid ◽

The Family ◽

Introduced Pest ◽

First Time

Abstract The tomato leafminer Tuta absoluta (Meyrick) is one of the most devastating pests of greenhouse and outdoor tomato crops. Since it is a newly introduced pest in Iran, there is an important need to search for its natural enemies. In the course of a survey on the natural enemies of this pest, samplings were carried out in tomato greenhouses heavily infested with the tomato leafminer, in the Borazjan region of the Bushehr province in Iran. Leaves with mines were reared in the laboratory until emergence of parasitoids. A single parasitoid species of the family Eulophidae was reared and identified as Neochrysocharis formosus (Westwood 1833). This species is reported for the first time on the tomato leafminer in Iran. Such information may help in developing biological control programs to control this serious pest.

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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 ◽

10.1139/g93-078 ◽

1993 ◽

Vol 36 (3) ◽

pp. 580-587 ◽

Cited By ~ 77

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.

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

Phytoprotection ◽

10.7202/706036ar ◽

2005 ◽

Vol 74 (1) ◽

pp. 51-67 ◽

Cited By ~ 5

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.

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Development of an ELISA-Based Method for Testing Aflatoxigenicity and Aflatoxigenic Variability among Aspergillus species in Culture

10.1101/523506 ◽

2019 ◽

Author(s):

Lagat Kipkemboi Micah ◽

Faith Jebet Toroitich ◽

Meshack Amos Obonyo

Keyword(s):

Biological Control ◽

Aflatoxin Production ◽

Toxin Production ◽

Field Trials ◽

Control Programs ◽

Color Changes ◽

Visual Color ◽

Aflatoxigenic Fungi ◽

Maize Kernels ◽

First Time

AbstractAflatoxins contaminate foodstuff posing a severe threat to human health because chronic exposure is linked to liver cancer while acute exposure may cause death. Therefore, it is of interest to reduce the contamination of crops by aflatoxins in the field and post-harvest. Among the current technologies being developed is the deployment of non-aflatoxigenic strains of Aspergillus species to competitively exclude aflatoxigenic conspecifics from crops in the field thereby curtailing aflatoxin production by the former. The success in this endeavor makes the non-aflatoxigenic fungi good candidates for biological control programs. However, the current techniques for segregating non-aflatoxigenic from aflatoxigenic fungi suffer two main drawbacks: they are based on morphological and chemical tests with a combination of visual color changes detected in a culture plate which suffer some degree of inaccuracy. Secondly, the existing methods are incapable of accurately quantifying aflatoxin production by fungi in culture. We developed a culture system for inducing aflatoxin production by Aspergillus using maize kernels as growth substrate followed by quantification using ELISA. The method was compared to the Dichlorvos-Ammonia (DV-AM) method for determining aflatoxigenicity. Our findings encapsulate a method more robust than the currently used DV-AM approach because, for the first time, we are able to assess aflatoxigenicity and aflatoxigenic variability among Aspergillus species earlier classified as non-aflatoxigenic by the DV-AM method. Furthermore, the new method presents an opportunity to attribute toxin production by actively growing fungal cultures. We believe this method when further developed presents a chance to study and predict fungal behavior prior to field trials for biological control programs.

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Detection and Identification of Viruses in Economically Important Insects

Microscopy and Microanalysis ◽

10.1017/s1431927600035820 ◽

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.

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