339 results match your criteria resistance cry1ab


Cellular Localization of Exogenous Cry1Ab/c and its Interaction with Plasma Membrane Ca-ATPase in Transgenic Rice.

Front Bioeng Biotechnol 2021 2;9:759016. Epub 2021 Nov 2.

Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing, China.

The cellular localization of exogenous proteins expressed in transgenic crops not only determines their stability, but also their effects on crop growth and development, including under stressful conditions; however, the underlying molecular mechanisms remain unknown. Here, we determined the cellular distribution of exogenously expressed Cry1Ab/c protein in insect-resistant transgenic rice Huahui-1 (HH1) cells through subcellular localization, immunohistochemistry, immunofluorescence, and western blot analyses. Interaction between the Cry1Ab/c protein and the preliminarily screened endogenous plasma membrane protein Ca-ATPase was investigated through yeast two-hybrid, bimolecular fluorescence complementation (BIFC), and co-immunoprecipitation analyses. Read More

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November 2021

Development of Economic Thresholds Toward Bollworm (Lepidoptera: Noctuidae), Management in Bt Cotton, and Assessment of the Benefits From Treating Bt Cotton With Insecticide.

J Econ Entomol 2021 Oct 9. Epub 2021 Oct 9.

Department of Entomology, Texas A&M University, 2475 TAMU, College Station, TX 77843, USA.

Widespread field-evolved resistance of bollworm [Helicoverpa zea (Boddie)] to Cry1 and Cry2 Bt proteins has threatened the utility of Bt cotton for managing bollworm. Consequently, foliar insecticide applications have been widely adopted to provide necessary additional control. Field experiments were conducted across the Mid-South and in Texas to devise economic thresholds for foliar insecticide applications targeting bollworm in cotton. Read More

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October 2021

Cadherin Protein Is Involved in the Action of Cry1Ac Toxin in .

Toxins (Basel) 2021 09 15;13(9). Epub 2021 Sep 15.

Key Laboratory of Integrated Pest Management on Crops in East China (MARA), College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China.

Transgenic crops expressing (Bt) insecticidal proteins have been extensively planted for insect pest control, but the evolution of Bt resistance in target pests threatens the sustainability of this approach. Mutations of cadherin in the midgut brush border membrane was associated with Cry1Ac resistance in several lepidoptera species, including the Asian corn borer, , a major pest of maize in Asian-Western Pacific countries. However, the causality of cadherin () with Cry1Ac resistance remains to be clarified. Read More

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September 2021

ATP-binding cassette transporter subfamily C members 2, 3 and cadherin protein are susceptibility-determining factors in Bombyx mori for multiple Bacillus thuringiensis Cry1 toxins.

Insect Biochem Mol Biol 2021 12 22;139:103649. Epub 2021 Sep 22.

Institute of Agrobiological Sciences, NARO, 1-2 Ohwashi, Tsukuba, Ibaraki 305-8634, Japan. Electronic address:

Field-evolved resistance of insect pests to Bacillus thuringiensis (Bt) toxins (Cry toxins) is a threat to the efficacy of Bt-based bio-insecticides and transgenic crops. Recent reports have suggested that ATP-binding cassette transporter subfamily C2 (ABCC2) and cadherin-like receptor play important roles in conferring susceptibility to Cry1 toxins. However, the receptors involved in Bt susceptibility in each insect remain unclear. Read More

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December 2021

Managing Fall Armyworm in Africa: Can Bt Maize Sustainably Improve Control?

J Econ Entomol 2021 10;114(5):1934-1949

Department of Entomology, University of Arizona, Tucson, AZ 85721, USA.

The recent invasion of Africa by fall armyworm, Spodoptera frugiperda, a lepidopteran pest of maize and other crops, has heightened concerns about food security for millions of smallholder farmers. Maize genetically engineered to produce insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) is a potentially useful tool for controlling fall armyworm and other lepidopteran pests of maize in Africa. In the Americas, however, fall armyworm rapidly evolved practical resistance to maize producing one Bt toxin (Cry1Ab or Cry1Fa). Read More

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October 2021

The draft genome of the Asian corn borer yields insights into ecological adaptation of a devastating maize pest.

Insect Biochem Mol Biol 2021 11 21;138:103638. Epub 2021 Aug 21.

CAS Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 200032, China; CAS Center for Excellence in Biotic Interactions, University of the Chinese Academy of Sciences, Beijing, 100049, China. Electronic address:

The Asian corn borer (ACB) is the most devastating pest on maize in the western Pacific region of Asia. Despite broad interests in insecticide resistance, seasonal adaptation, and larval color mimicry regarding the ACB system, lacking of reference genomic information and a powerful gene editing approach have hindered the in-depth studies of these aspects. Here we present a 455. Read More

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November 2021

Assessment of the 2019 post-market environmental monitoring report on the cultivation of genetically modified maize MON 810 in the EU.

EFSA J 2021 Jul 7;19(7):e06683. Epub 2021 Jul 7.

Following a request from the European Commission, the EFSA assessed the 2019 post-market environmental monitoring (PMEM) report on the cultivation of Cry1Ab-expressing maize event MON 810. Like previous years, there was full compliance with refuge requirement in Portugal and partial compliance with refuge requirements by Spanish farmers growing MON 810 varieties. European and Mediterranean corn borer populations collected from north-eastern Spain during the 2019 maize growing season and tested for Cry1Ab susceptibility show no symptoms of resistance to maize MON 810. Read More

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Managing resistance evolution to transgenic maize in corn borers in Spain.

Crit Rev Biotechnol 2021 Jun 21:1-19. Epub 2021 Jun 21.

INRAE, Eco-Innov, Université Paris-Saclay, Thiverval-Grignon, France.

Since 1998, genetically engineered maize varieties expressing the insecticidal Cry1Ab protein (i.e. event MON 810) have been grown in the European Union (EU), mainly in Spain. Read More

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Hetero-oligomerization of Bacillus thuringiensis Cry1A proteins enhance binding to the ABCC2 transporter of Spodoptera exigua.

Biochem J 2021 07;478(13):2589-2600

Instituto Universitario de Biotecnología y Biomedicina (BIOTECMED), Department of Genetics, Universitat de València, 46100 Burjassot, Spain.

The ATP binding cassette (ABC) transporters are membrane proteins that can act as putative receptors for Cry proteins from Bacillus thuringiensis (Bt) in the midgut of different insects. For the beet armyworm, Spodoptera exigua, ABCC2 and ABCC3 have been found to interact with Cry1A proteins, the main insecticidal proteins used in Bt crops, as well as Bt-based pesticides. The ABCC2 has shown to have specific binding towards Cry1Ac and is involved in the toxic process of Cry1A proteins, but the role of this transporter and how it relates with the Cry1A proteins is still unknown. Read More

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SfABCC2 transporter extracellular loops 2 and 4 are responsible for the Cry1Fa insecticidal specificity against Spodoptera frugiperda.

Insect Biochem Mol Biol 2021 08 10;135:103608. Epub 2021 Jun 10.

Institute of Entomology, School of Life Sciences, Central China Normal University, Wuhan, 430079, PR China. Electronic address:

Bacillus thuringiensis (Bt) bacteria produce Cry toxins that kill insect pests. Insect specificity of Cry toxins relies on their binding to larval gut membrane proteins such as cadherin and ATP-binding cassette (ABC) transporter proteins. Mutations in ABC transporters have been implicated in high levels of resistance to Cry toxins in multiple pests. Read More

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Docking-based generation of antibodies mimicking Cry1A/1B protein binding sites as potential insecticidal agents against diamondback moth (Plutella xylostella).

Pest Manag Sci 2021 Oct 23;77(10):4593-4606. Epub 2021 Jun 23.

Key Lab of Food Quality and Safety of Jiangsu Province-State Key Laboratory Breeding Base, Key Laboratory of Control Technology and Standard for Agro-product Safety and Quality, Ministry of Agriculture, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, P. R. China.

Background: Broad use of insecticidal Cry proteins from Bacillus thuringiensis in biopesticides and transgenic crops has resulted in cases of practical field resistance, highlighting the need for novel approaches to insect control. Previously we described an anti-Cry1Ab idiotypic-antibody (B12-scFv) displaying toxicity against rice leafroller (Cnaphalocrocis medinalis) larvae, supporting the potential of antibodies for pest control. The goal of the present study was to generate insecticidal antibodies against diamondback moth (Plutella xylostella) larvae. Read More

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October 2021

Baseline Susceptibility and Laboratory Selection of Resistance to Bt Cry1Ab Protein of Chinese Populations of Yellow Peach Moth, (Guenée).

Toxins (Basel) 2021 05 6;13(5). Epub 2021 May 6.

State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, No. 2, West Yuanmingyuan Road, Beijing 100193, China.

Yellow Peach Moth (YPM), (Guenée), is one of the most destructive maize pests in the Huang-Huai-Hai summer maize region of China. Transgenic Bacillus thuringiensis (Bt) maize provides an effective means to control this insect pest in field trials. However, the establishment of Bt resistance to target pests is endangering the continued success of Bt crops. Read More

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The Rapid Evolution of Resistance to Vip3Aa Insecticidal Protein in (Walker) Is Not Related to Altered Binding to Midgut Receptors.

Toxins (Basel) 2021 05 20;13(5). Epub 2021 May 20.

State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, No. 2, West Yuanmingyuan Road, Beijing 100193, China.

Laboratory selection for resistance of field populations is a well-known and useful tool to understand the potential of insect populations to evolve resistance to insecticides. It provides us with estimates of the frequency of resistance alleles and allows us to study the mechanisms by which insects developed resistance to shed light on the mode of action and optimize resistance management strategies. Here, a field population of was subjected to laboratory selection with either Vip3Aa, Cry1Ab, or Cry1F insecticidal proteins from . Read More

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Development of marker-free transgenic pigeon pea (Cajanus cajan) expressing a pod borer insecticidal protein.

Sci Rep 2021 05 18;11(1):10543. Epub 2021 May 18.

Advanced Laboratory for Plant Genetic Engineering (ALPGE), IIT-Kharagpur, Kharagpur, India.

Pigeon pea, a grain legume of the semiarid tropics, is a rich source of high-quality protein. The productivity of this pulse is seriously affected by lepidopteron insect pests. To generate a sustainable insect-resistant plant, synthetically prepared bioactive key constituents of a crystal protein (Syn Cry1Ab) of Bacillus thuringiensis were expressed in pigeon pea under the guidance of a tissue-specific promoter of the RuBP carboxylase/oxygenase small subunit (rbcS) gene. Read More

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Foreign Cry1Ab/c Delays Flowering in Insect-Resistant Transgenic Rice via Interaction With Hd3a Florigen.

Front Plant Sci 2021 11;12:608721. Epub 2021 Feb 11.

Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing, China.

Genetic modifications in rice, which resulted in insect resistance, have been highly efficacious. However, they have also induced undesirable secondary phenotypes, such as delayed flowering. The molecular mechanisms associated with these unwanted effects remain unclear. Read More

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February 2021

Transformation and functional verification of Cry5Aa in cotton.

Sci Rep 2021 02 2;11(1):2805. Epub 2021 Feb 2.

Institute of Cotton Science, Hunan Agricultural University, Changsha, China.

Most of the cotton bollworm-resistant genes applied in cotton are more than 20 years and they all belong to Cry1Ab/c family, but the insect-resistant effects of Cry5Aa on cotton were rarely reported. The possible risk of resistance is increasing. The study synthesized a novel bollworm-resistant gene Cry5Aa artificially based on preferences of cotton codon. Read More

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February 2021

Populations of (Boddie) in the Southeastern United States are Commonly Resistant to Cry1Ab, but Still Susceptible to Vip3Aa20 Expressed in MIR 162 Corn.

Toxins (Basel) 2021 01 15;13(1). Epub 2021 Jan 15.

Department of Entomology, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA.

The corn earworm, (Boddie), is a major pest targeted by pyramided (Bt) corn and cotton in the U.S. Cry1Ab is one of the first insecticidal toxins used in Bt crops, while Vip3A is a relatively new toxin that has recently been incorporated into Cry corn with event MIR 162 and Cry cotton varieties to generate pyramided Bt traits targeting lepidopteran pests including . Read More

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January 2021

Safety assessment of genetically modified rice expressing Cry1Ab protein in Sprague-Dawley rats.

Sci Rep 2021 01 13;11(1):1126. Epub 2021 Jan 13.

Research Center for Food Hygiene and Safety, School of Public Health, Shahid Sadoughi University of Medical Sciences, Shohadaye Gomnam Blvd., Yazd, 8916188638, Islamic Republic of Iran.

Rice is considered one of the most important staple food crops. Genetically modified (GM) Bt rice, harbored cry1Ab gene expressing the insect-resistance protein has been developed to resistance to the insects. In this study, we assessed the safety of the GM Bt rice on Sprague-Dawley rats for 90 days. Read More

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January 2021

Toxicity of Cry1-Class, Cry2Aa, and Vip3Aa19 Bt proteins and their interactions against yellow peach Moth, Conogethes punctiferalis (Guenée) (Lepidoptera: Crambidae).

J Invertebr Pathol 2021 01 26;178:107507. Epub 2020 Nov 26.

State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, No. 2, West Yuanmingyuan Road, Beijing 100193, China. Electronic address:

Transgenic plants expressing insecticidal proteins from the Bacillus thuringiensis (Bt) have provided an effective way to control target pests. However, the toxicity of Bt proteins against yellow peach moth (YPM), Conogethes punctiferalis (Guenée), one of the most serious maize pests in China, has not received much study. Therefore, we performed diet-overlay bioassays to evaluate the insecticidal activities of Cry1Ab, Cry1Ac, Cry1Fa, Cry1Ah, Cry1Ie, Cry2Aa, and Vip3Aa19, as well as the interaction between Cry1-Class, Cry2Aa, and Vip3Aa19 against YPM. Read More

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January 2021

Two ABC transporters are differentially involved in the toxicity of two Bacillus thuringiensis Cry1 toxins to the invasive crop-pest Spodoptera frugiperda (J. E. Smith).

Pest Manag Sci 2021 Mar 19;77(3):1492-1501. Epub 2020 Nov 19.

Guangdong Laboratory of Lingnan Modern Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China.

Background: The fall armyworm Spodoptera frugiperda is a major agricultural pest that has invaded the East Hemisphere since 2016, generating a serious threat to food security worldwide including Africa and Asia. The Cry toxins produced by Bacillus thuringiensis (Bt) have been shown to be effective against this insect pest. In different insect ABC transporters (ABCC2 or ABCC3) have been shown to be involved as receptors of some Cry1 toxins. Read More

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Assessment of the 2018 post-market environmental monitoring report on the cultivation of genetically modified maize MON 810 in the EU.

EFSA J 2020 Oct 12;18(10):e06245. Epub 2020 Oct 12.

Following a request from the European Commission, the EFSA assessed the 2018 post-market environmental monitoring (PMEM) report on the cultivation of Cry1Ab-expressing maize event MON 810. Like previous years, there was partial compliance with refuge requirements by Spanish farmers growing MON 810 varieties. European and Mediterranean corn borer populations collected from north-eastern Spain during the 2018 maize growing season and tested for Cry1Ab susceptibility show no symptoms of resistance to maize MON 810. Read More

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October 2020

Introgression Breeding in Cowpea [ (L.) Walp.].

Front Plant Sci 2020 16;11:567425. Epub 2020 Sep 16.

Genetic Resources Center, International Institute of Tropical Agriculture, Ibadan, Nigeria.

The narrow base of genetic diversity characteristic of cowpea can be attributed to it being self-pollinating, evolving from narrow wild germplasm and exhibiting very limited gene flow between wild and cultivated types. Backcrossing to introduce simply inherited desirable traits and utilization of improved breeding lines and varieties as parents in crossing programs further narrowed the genetic base of cowpea varieties. In most cowpea breeding programs, genes for resistance and market traits were pyramided into lines characterized by high levels of acceptance to farmers and consumers. Read More

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September 2020

ABC transporter mutations in Cry1F-resistant fall armyworm (Spodoptera frugiperda) do not result in altered susceptibility to selected small molecule pesticides.

Pest Manag Sci 2021 Feb 10;77(2):949-955. Epub 2020 Oct 10.

Department of Entomology and Plant Pathology, University of Tennessee, Knoxville, TN, USA.

Background: Transgenic crops producing Cry and Vip3 insecticidal proteins from the bacterium Bacillus thuringiensis provide effective control of the fall armyworm, Spodoptera frugiperda J. E. Smith. Read More

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February 2021

Transgene behavior in Zea mays L. crosses across different genetic backgrounds: Segregation patterns, cry1Ab transgene expression, insecticidal protein concentration and bioactivity against insect pests.

PLoS One 2020 10;15(9):e0238523. Epub 2020 Sep 10.

Plant Ecological Genetics, Institute of Integrative Biology, Department of Environmental Systems Science, ETH Zürich, Zürich, Switzerland.

Brazil and South Africa, countries with economies in transition, are characterized by a dual agrarian structure co-occurring, sometimes, alongside in the same region. Large-scale commercial farming produces crops for export to global markets on the one hand, and small-scale farming, on the other hand, provides for subsistence and local markets. In both systems, maize (Zea mays) is a key crop for these two countries. Read More

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October 2020

Bacillus thuringiensis Cry1Ab Domain III β-22 Mutants with Enhanced Toxicity to Spodoptera frugiperda (J. E. Smith).

Appl Environ Microbiol 2020 10 28;86(22). Epub 2020 Oct 28.

Instituto de Biotecnología, Universidad Nacional Autónoma de Mexico, Cuernavaca, Morelos, México

The fall armyworm, , is an invasive maize pest that has spread from the Americas into Africa and Asia and causes severe crop damage worldwide. Most populations of show low susceptibility to (Bt) Cry1Ab or Cry1Ac toxins, which have been proved to be effective against several other lepidopteran pests. In addition, has evolved resistance to transgenic maize expressing Cry1Fa toxin. Read More

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October 2020

Demographic Performance of Populations on Dual and Triple-Gene Bt Cotton.

Toxins (Basel) 2020 08 28;12(9). Epub 2020 Aug 28.

Department of Entomology and Nematology, University of Florida, Gainesville, FL 32608, USA.

Insecticidal toxins from (Bt) are valuable tools for pest management worldwide, contributing to the management of human disease insect vectors and phytophagous insect pests of agriculture and forestry. Here, we report the effects of dual and triple Bt toxins expressed in transgenic cotton cultivars on the fitness and demographic performance of (Boddie)-a noctuid pest, known as cotton bollworm and corn earworm. Life-history traits were determined for individuals of three field populations from a region where overwintering is likely. Read More

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A Framework for Effective Bt Maize IRM Programs: Incorporation of Lessons Learned From Resistance Development.

Authors:
Gustav Bouwer

Front Bioeng Biotechnol 2020 10;8:717. Epub 2020 Jul 10.

Invertebrate Pathology and Biocontrol Laboratory, School of Molecular and Cell Biology, University of the Witwatersrand, Johannesburg, South Africa.

Bt maize is genetically engineered to express insecticidal proteins from the bacterium . Bt maize is used extensively by South African farmers to reduce yield losses caused by lepidopteran larvae. Starting in the 2004/2005 season, severe -associated damage to Cry1Ab-expressing Bt maize was noted by South African farmers. Read More

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Decline in Sublethal Effects of Bt Corn on Corn Earworm (Lepidoptera: Noctuidae) Linked to Increasing Levels of Resistance.

J Econ Entomol 2020 10;113(5):2241-2249

Department of Entomology and Plant Pathology, North Carolina State University, the Vernon G. James Research and Extension Center, Plymouth, NC.

As part of an ongoing longitudinal study in North and South Carolina, this study reports the recovery of Helicoverpa zea (Boddie) pupae in field trials with genetically engineered corn, Zea mays L., hybrids that produce insecticidal toxins from Bacillus thuringiensis (Bt) in 2017-2019. In total, 10,400 corn ears were collected, which led to 3,927 H. Read More

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October 2020

Exogenous Cry1Ab/c Protein Recruits Different Endogenous Proteins for Its Function in Plant Growth and Development.

Authors:
Jianmei Fu Biao Liu

Front Bioeng Biotechnol 2020 30;8:685. Epub 2020 Jun 30.

Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing, China.

Current risk assessments of transgenic crops do not take into consideration whether exogenous proteins interact with endogenous proteins and thereby induce unintended effects in the crops. Therefore, the unintended effects through protein interactions in insect-resistant transgenic rice merit investigation. Here, a yeast two-hybrid assay was used to evaluate interactions between (Bt) protein-derived Cry1Ab/c insect resistance rice Huahui-1 and the endogenous proteins of its parental rice Minghui-63. Read More

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Evaluation of the Toxicity of Supernatant Cultures and Spore-Crystal Mixtures of Bacillus thuringiensis Strains Isolated from Algeria.

Curr Microbiol 2020 Oct 10;77(10):2904-2914. Epub 2020 Jul 10.

ERI de Biotecnología y Biomedicina (BIOTECMED), Department of Genetics, Universitat de València, 46100, Burjassot, Spain.

Bacillus thuringiensis (Bt) is the most used technology for biological control of insect pathogens worldwide. In order to select new Bt candidates challenging the emergence of insect's resistance, a mass bioassay and molecular screening was performed on an autochthonous collection. Toxicity assays against neonate larvae of three lepidopteran species (Mamestra brassicae, Grapholita molesta, and Spodoptera exigua) were conducted using spore-crystal mixtures and supernatant cultures of 49 Bt isolates harboring at least one gene coding for a lepidopteran-specific insecticidal protein. Read More

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October 2020