Using trap crops for control of Acalymma vittatum (Coleoptera: Chrysomelidae) reduces insecticide use in butternut squash.

Science.gov (United States)

Cavanagh, A; Hazzard, R; Adler, L S; Boucher, J

2009-06-01

Striped cucumber beetle, Acalymma vittatum F., is the primary insect pest of cucurbit crops in the northeastern United States. Adult beetles colonize squash crops from field borders, causing feeding damage at the seedling stage and transmitting bacterial wilt Erwinia tracheiphila Hauben et al. 1999. Conventional control methods rely on insecticide applications to the entire field, but surrounding main crops with a more attractive perimeter could reduce reliance on insecticides. A. cittatum shows a marked preference for Blue Hubbard squash (Cucurbita maxima Duchesne) over butternut squash (C. moschata Poir). Given this preference, Blue Hubbard squash has the potential to be an effective perimeter trap crop. We evaluated this system in commercial butternut fields in 2003 and 2004, comparing fields using perimeter trap cropping with Blue Hubbard to conventionally managed fields. In 2003, we used a foliar insecticide to control beetles in the trap crop borders, and in 2004, we compared systemic and foliar insecticide treatments for the trap crop borders. We found that using a trap crop system reduced or eliminated the need to spray the main crop area, reducing insecticide use by up to 94% compared with conventional control methods, with no increase in herbivory or beetle numbers. We surveyed the growers who participated in these experiments and found a high level of satisfaction with the effectiveness and simplicity of the system. These results suggest that this method of pest control is both effective and simple enough in its implementation to have high potential for adoption among growers.

The effects of Fe2O3 nanoparticles on physiology and insecticide activity in non-transgenic and Bt-transgenic cotton

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Nhan eLe Van

2016-01-01

Full Text Available As the demands for nanotechnology and nanoparticle (NP applications in agriculture increase, the ecological risk has drawn more attention because of the unpredictable results of interactions between NPs and transgenic crops. In this study, we investigated the effects of various concentrations of Fe2O3 NPs on Bt-transgenic cotton in comparison with conventional cotton for 10 days. Each treatment was conducted in triplicate, and each experiment was repeated three times. Results demonstrated that Fe2O3 nanoparticles (NPs inhibited the plant height and root length of Bt-transgenic cotton and promoted root hairs and biomass of non-transgenic cotton. Nutrients such as Na and K in Bt-transgenic cotton roots increased, while Zn contents decreased with Fe2O3 NPs. Most hormones in the roots of Bt-transgenic cotton increased at low Fe2O3 NP exposure (100 mg·L−1 but decreased at high concentrations of Fe2O3 NPs (1000 mg·L−1. Fe2O3 NPs increased the Bt-toxin in leaves and roots of Bt-transgenic cotton. Fe2O3 NPs were absorbed into roots, then transported to the shoots of both Bt-transgenic and non-transgenic cottons. The bioaccumulation of Fe2O3 NPs in plants might be a potential risk for agricultural crops and affect the environment and human health.

Evolution of Bacillus thuringiensis Cry toxins insecticidal activity.

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Bravo, Alejandra; Gómez, Isabel; Porta, Helena; García-Gómez, Blanca Ines; Rodriguez-Almazan, Claudia; Pardo, Liliana; Soberón, Mario

2013-01-01

Insecticidal Cry proteins produced by Bacillus thuringiensis are use worldwide in transgenic crops for efficient pest control. Among the family of Cry toxins, the three domain Cry family is the better characterized regarding their natural evolution leading to a large number of Cry proteins with similar structure, mode of action but different insect specificity. Also, this group is the better characterized regarding the study of their mode of action and the molecular basis of insect specificity. In this review we discuss how Cry toxins have evolved insect specificity in nature and analyse several cases of improvement of Cry toxin action by genetic engineering, some of these examples are currently used in transgenic crops. We believe that the success in the improvement of insecticidal activity by genetic evolution of Cry toxins will depend on the knowledge of the rate-limiting steps of Cry toxicity in different insect pests, the mapping of the specificity binding regions in the Cry toxins, as well as the improvement of mutagenesis strategies and selection procedures. © 2012 The Authors. Microbial Biotechnology © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.

[Biofuels, food security and transgenic crops].

Science.gov (United States)

Acosta, Orlando; Chaparro-Giraldo, Alejandro

2009-01-01

Soaring global food prices are threatening to push more poor people back below the poverty line; this will probably become aggravated by the serious challenge that increasing population and climate changes are posing for food security. There is growing evidence that human activities involving fossil fuel consumption and land use are contributing to greenhouse gas emissions and consequently changing the climate worldwide. The finite nature of fossil fuel reserves is causing concern about energy security and there is a growing interest in the use of renewable energy sources such as biofuels. There is growing concern regarding the fact that biofuels are currently produced from food crops, thereby leading to an undesirable competition for their use as food and feed. Nevertheless, biofuels can be produced from other feedstocks such as lingo-cellulose from perennial grasses, forestry and vegetable waste. Biofuel energy content should not be exceeded by that of the fossil fuel invested in its production to ensure that it is energetically sustainable; however, biofuels must also be economically competitive and environmentally acceptable. Climate change and biofuels are challenging FAO efforts aimed at eradicating hunger worldwide by the next decade. Given that current crops used in biofuel production have not been domesticated for this purpose, transgenic technology can offer an enormous contribution towards improving biofuel crops' environmental and economic performance. The present paper critically presents some relevant relationships between biofuels, food security and transgenic plant technology.

Accurate measurement of transgene copy number in crop plants using droplet digital PCR.

Science.gov (United States)

Collier, Ray; Dasgupta, Kasturi; Xing, Yan-Ping; Hernandez, Bryan Tarape; Shao, Min; Rohozinski, Dominica; Kovak, Emma; Lin, Jeanie; de Oliveira, Maria Luiza P; Stover, Ed; McCue, Kent F; Harmon, Frank G; Blechl, Ann; Thomson, James G; Thilmony, Roger

2017-06-01

Genetic transformation is a powerful means for the improvement of crop plants, but requires labor- and resource-intensive methods. An efficient method for identifying single-copy transgene insertion events from a population of independent transgenic lines is desirable. Currently, transgene copy number is estimated by either Southern blot hybridization analyses or quantitative polymerase chain reaction (qPCR) experiments. Southern hybridization is a convincing and reliable method, but it also is expensive, time-consuming and often requires a large amount of genomic DNA and radioactively labeled probes. Alternatively, qPCR requires less DNA and is potentially simpler to perform, but its results can lack the accuracy and precision needed to confidently distinguish between one- and two-copy events in transgenic plants with large genomes. To address this need, we developed a droplet digital PCR-based method for transgene copy number measurement in an array of crops: rice, citrus, potato, maize, tomato and wheat. The method utilizes specific primers to amplify target transgenes, and endogenous reference genes in a single duplexed reaction containing thousands of droplets. Endpoint amplicon production in the droplets is detected and quantified using sequence-specific fluorescently labeled probes. The results demonstrate that this approach can generate confident copy number measurements in independent transgenic lines in these crop species. This method and the compendium of probes and primers will be a useful resource for the plant research community, enabling the simple and accurate determination of transgene copy number in these six important crop species. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

Development of ELISA for the detection of transgenic vegetative insecticidal protein in GM crops/produce.

Science.gov (United States)

Kumar, R

2012-01-11

In the process of the development of insect-resistant genetically modified (GM) crops and also to evaluate the consistency in the expression of toxin under field conditions, immunological assays are commonly being used. An immunoassay was developed to support the labelling of vegetative insecticidal protein (Vip3A)-based GM produce. The developed ELISA for the measurement of Vip3A is a triple antibody sandwich procedure utilising a polyclonal capture antibody (mouse anti-Vip3A) and a polyclonal detection antibody (rabbit anti-Vip3A) followed by use of a third HRP-conjugated anti-species antibody (goat anti-rabbit IgG). The limit of detection limit of the ELISA assay was 16 ng ml(-1) with a linear quantification range from approximately 31 to 500 ng ml(-1) of Vip3A protein. Furthermore, the assay was in-house validated with GM brinjal samples. The assay was specific, sensitive and reproducible, which can be helpful to detect and track down the spread of unapproved and intentionally/unintentionally released GM produce harbouring Vip protein.

THE POTENTIAL ROLE OF REMOTE SENSING IN TRANSGENIC CROP MONITORING PROGRAMS

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Sustainable agriculture combines efficient production with wise stewardship of the earth's resources. Development of environmentally benign production techniques is one focus of sustainable agriculture. The new transgenic crops producing toxic proteins that target specific crop p...

The ecological risks of transgenic plants.

Science.gov (United States)

Giovannetti, Manuela

2003-01-01

Biotechnologies have been utilized "ante litteram" for thousands of years to produce food and drink and genetic engineering techniques have been widely applied to produce many compounds for human use, from insulin to other medicines. The debate on genetically modified (GM) organisms broke out all over the world only when GM crops were released into the field. Plant ecologists, microbiologists and population geneticists carried out experiments aimed at evaluating the environmental impact of GM crops. The most significant findings concern: the spread of transgenes through GM pollen diffusion and its environmental impact after hybridisation with closely related wild species or subspecies; horizontal gene transfer from transgenic plants to soil microbes; the impact of insecticide proteins released into the soil by transformed plants on non-target microbial soil communities. Recent developments in genetic engineering produced a technology, dubbed "Terminator", which protects patented genes introduced in transgenic plants by killing the seeds in the second generation. This genetic construct, which interferes so heavily with fundamental life processes, is considered dangerous and should be ex-ante evaluated taking into account the data on "unexpected events", as here discussed, instead of relying on the "safe until proven otherwise" claim. Awareness that scientists, biotechnologists and genetic engineers cannot answer the fundamental question "how likely is that transgenes will be transferred from cultivated plants into the natural environment?" should foster long-term studies on the ecological risks and benefits of transgenic crops.

Accurate measure of transgene copy number in crop plants using droplet digital PCR

Science.gov (United States)

Genetic transformation is a powerful means for the improvement of crop plants, but requires labor- and resource-intensive methods. An efficient method for identifying single-copy transgene insertion events from a population of independent transgenic lines is desirable. Currently, transgene copy numb...

Elevated atmospheric ozone increases concentration of insecticidal Bacillus thuringiensis (Bt) Cry1Ac protein in Bt Brassica napus and reduces feeding of a Bt target herbivore on the non-transgenic parent

International Nuclear Information System (INIS)

Himanen, Sari J.; Nerg, Anne-Marja; Nissinen, Anne; Stewart, C. Neal; Poppy, Guy M.; Holopainen, Jarmo K.

2009-01-01

Sustained cultivation of Bacillus thuringiensis (Bt) transgenic crops requires stable transgene expression under variable abiotic conditions. We studied the interactions of Bt toxin production and chronic ozone exposure in Bt cry1Ac-transgenic oilseed rape and found that the insect resistance trait is robust under ozone elevations. Bt Cry1Ac concentrations were higher in the leaves of Bt oilseed rape grown under elevated ozone compared to control treatment, measured either per leaf fresh weight or per total soluble protein of leaves. The mean relative growth rate of a Bt target herbivore, Plutella xylostella L. larvae was negative on Bt plants in all ozone treatments. On the non-transgenic plants, larval feeding damage was reduced under elevated ozone. Our results indicate the need for monitoring fluctuations in Bt toxin concentrations to reveal the potential of ozone exposure for altering dosing of Bt proteins to target and non-target herbivores in field environments experiencing increasing ozone pollution. - Elevated atmospheric ozone can induce fluctuations in insecticidal protein concentrations in transgenic plants

Elevated atmospheric ozone increases concentration of insecticidal Bacillus thuringiensis (Bt) Cry1Ac protein in Bt Brassica napus and reduces feeding of a Bt target herbivore on the non-transgenic parent

Energy Technology Data Exchange (ETDEWEB)

Himanen, Sari J. [University of Kuopio, Department of Environmental Science, P.O. Box 1627, FIN-70211 Kuopio (Finland)], E-mail: sari.himanen@uku.fi; Nerg, Anne-Marja [University of Kuopio, Department of Environmental Science, P.O. Box 1627, FIN-70211 Kuopio (Finland); Nissinen, Anne [University of Kuopio, Department of Environmental Science, P.O. Box 1627, FIN-70211 Kuopio (Finland); MTT Agrifood Research Finland, Plant Protection, FIN-31600 Jokioinen (Finland); Stewart, C. Neal [University of Tennessee, Department of Plant Sciences, Knoxville, TN 37996-4561 (United States); Poppy, Guy M. [University of Southampton, School of Biological Sciences, Southampton SO16 7PX (United Kingdom); Holopainen, Jarmo K. [University of Kuopio, Department of Environmental Science, P.O. Box 1627, FIN-70211 Kuopio (Finland)

2009-01-15

Sustained cultivation of Bacillus thuringiensis (Bt) transgenic crops requires stable transgene expression under variable abiotic conditions. We studied the interactions of Bt toxin production and chronic ozone exposure in Bt cry1Ac-transgenic oilseed rape and found that the insect resistance trait is robust under ozone elevations. Bt Cry1Ac concentrations were higher in the leaves of Bt oilseed rape grown under elevated ozone compared to control treatment, measured either per leaf fresh weight or per total soluble protein of leaves. The mean relative growth rate of a Bt target herbivore, Plutella xylostella L. larvae was negative on Bt plants in all ozone treatments. On the non-transgenic plants, larval feeding damage was reduced under elevated ozone. Our results indicate the need for monitoring fluctuations in Bt toxin concentrations to reveal the potential of ozone exposure for altering dosing of Bt proteins to target and non-target herbivores in field environments experiencing increasing ozone pollution. - Elevated atmospheric ozone can induce fluctuations in insecticidal protein concentrations in transgenic plants.

CROP OF TRANSGENIC SOY-BEAN. PEASANT AND INDIGENOUS COMMUNITY EFFECTS OF EUSTERN PARAGUAY

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Hugo Florencio Centurión Mereles

2011-09-01

Full Text Available The Word offers us a critical glance about the economic and socio-cultural impacts of the transgenic crops in peasant and indigenous communities of the eastern region of Paraguay, it is given special attention to the use of Roundup, with the undoubted environment cost and the uncertain risks to human and animal health. The impacts and interactions that the techno-commoditization of the organisms genetically modified OGM have on the affected populations and the environment-species, soil, water, woods, flora, fauna is discussed in the Word.The extent of use of glyphosate on transgenic crops would involve not only the environment of the crop, but go to generate profound cultural changes, technological, of management, environmental, economical, social and legal, whose effects we already see them come with the decline of peasant and indigenous communities, that at not finding adequate strategies to face them, collapse as collectivity. The Word contains important elements to renew the debate and the critical thought in relation to the problematic of transgenic crop and its impact in indigenous and peasant populations.

Cloning of genes and developing transgenic crops with enhanced tolerance to salinity and drought (abstract)

International Nuclear Information System (INIS)

Bansal, K.C.; Chinnusamy, V.; Tayal, D.; Das, A.; Goel, D.; Yadav, V.; Singh, A.K.; Lakhshmi, K.

2005-01-01

Abiotic stresses represent the most limiting factors affecting agricultural productivity. In India more than 60% of total cultivated land is still rainfed and crops experience frequent droughts. Thus, we need to develop transgenic crops tolerant to drought, and other related abiotic stress factors such as salinity, low and high temperature stresses. At the National Research Centre on Plant Biotechnology, Indian Agricultural Research Institute (ICAR), we have initiated a programme on developing transgenic crops tolerant to a range of abiotic stresses. The major emphasis is on developing transgenic potato, tomato, mustard, rice and wheat. While, transgenic plants of potato. tomato and mustard have already been generated with osmotin gene and are at different stages of testing, other key genes imparting tolerance to abiotic stresses are being isolated from different species for producing transgenic rice and wheat cultivars tolerant to multiple stresses. Genes that have been isolated in our laboratory include ascorbate peroxidase gene (TaApx) and genes encoding transcription factor, CBFs (TaCBF2 and TaCBP3) from a drought tolerant wheat cultivar (C306), Lea1 cDNA from Brassica species, codA from Arthrobacter globiformis, and otsBA operon from E. coli. Apart from these stress-related genes, we have isolated a few stress-inducible promoters for deploying them in gene stacking in developing transgenic crops with enhanced tolerance to multiple abiotic stresses. The results will be presented. (author)

Using mass-release of engineered insects to manage insecticide resistance

International Nuclear Information System (INIS)

Alphey, Nina; Coleman, Paul G.; Donnelly, Christl A.

2006-01-01

Transgenic crops expressing insecticidal toxins derived from Bacillus thuringiensis (Bt) are widely used to control insect pests. The benefits of such crops would be lost if resistance to the toxins spread to a significant proportion of the pest population. The main resistance management method, mandatory in the US, is the high-dose/refuge strategy, requiring nearby refuges of toxin-free crops, and the use of toxin doses sufficiently high to kill not only wild type insects but also insects heterozygous for a resistance allele, thereby rendering the resistance functionally recessive. We propose that mass-release of harmless toxin-sensitive insects could substantially delay or even reverse the spread of resistance. Mass-release of such insects is an integral part of RIDL, a genetics-based method of pest control related to the Sterile Insect Technique. We used a population genetic mathematical model to analyze the effects of releasing male insects homozygous for a female-specific dominant lethal genetic construct, and concluded that this RIDL strategy could form an effective component of a resistance management scheme for insecticidal plants and other toxins. (author)

Using mass-release of engineered insects to manage insecticide resistance

Energy Technology Data Exchange (ETDEWEB)

Alphey, Nina [University of Oxford (United Kingdom). Dept. of Zoology; Alphey, Luke [Oxitec Limited, Oxford (United Kingdom); Coleman, Paul G [London School of Hygiene and Tropical Medicine (United Kingdom). Dept. of Infectious and Tropical Diseases; Donnelly, Christl A [Imperial College Faculty of Medicine, London (United Kingdom). Dept. of Infectious Disease Epidemiology

2006-07-01

Transgenic crops expressing insecticidal toxins derived from Bacillus thuringiensis (Bt) are widely used to control insect pests. The benefits of such crops would be lost if resistance to the toxins spread to a significant proportion of the pest population. The main resistance management method, mandatory in the US, is the high-dose/refuge strategy, requiring nearby refuges of toxin-free crops, and the use of toxin doses sufficiently high to kill not only wild type insects but also insects heterozygous for a resistance allele, thereby rendering the resistance functionally recessive. We propose that mass-release of harmless toxin-sensitive insects could substantially delay or even reverse the spread of resistance. Mass-release of such insects is an integral part of RIDL, a genetics-based method of pest control related to the Sterile Insect Technique. We used a population genetic mathematical model to analyze the effects of releasing male insects homozygous for a female-specific dominant lethal genetic construct, and concluded that this RIDL strategy could form an effective component of a resistance management scheme for insecticidal plants and other toxins. (author)

Agrofuels and transgenic crops: a couple that promotes the loss of food sovereignty

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Milena Espinosa

2013-11-01

Full Text Available In order to approach to understanding the threat agrofuels and transgenic crops pose to food sovereignty, this paper revises some statements in relation to the dynamics related to these proposals and the socio–environmental conflicts they generate. Thus, firstly,some key concepts are defined; then, a general revision of the agrofuel production and transgenic expansion context is made, pointing out the perspectives and risks of this couple; next, the agroenergy model effects on food sovereignty are briefly studied inLatin America through the case of Argentina, projected as an important agroenergy producer with large areas of land to cultivate transgenic soy for export; finally, some conclusions are presented: agrofuel production and transgenic crops have a negative impact on peasants and consumers because of the import of food, the increase of foodprices, the dependence on external agricultural inputs, land conflicts and the loss of agricultural diversity, in the end the loss of food sovereignty.

The Myth of Coexistence: Why Transgenic Crops Are Not Compatible With Agroecologically Based Systems of Production

Science.gov (United States)

Altieri, Miguel

2005-01-01

The coexistence of genetically modified (GM) crops and non-GM crops is a myth because the movement of transgenes beyond their intended destinations is a certainty, and this leads to genetic contamination of organic farms and other systems. It is unlikely that transgenes can be retracted once they have escaped, thus the damage to the purity of…

The effect of insecticide applications to melon crop on melon aphid and its natural enemies

International Nuclear Information System (INIS)

Guerra, J.; Gonzalez, J.E.; Ceballos, J.; Checa, B.

1999-01-01

Melons are an important export crop for Panama and are cultivated on more than 1000 ha of land. Long growing season, extending well into January, allows several generations and build up of heavy populations of an important insect pest, Aphis gossypii, the melon aphid. Growers find it difficult to cultivate melons without several applications of insecticides. Although the insecticide applications control the aphids, they may also have adverse effects on the natural enemies of the aphid, in particular the two predatory insects Cycloneda sanguinea and Chrysoperla carnea. The purpose of this research was to evaluate the impact of insecticide applications on these insects and on the yield of melons, and to estimate residues of the applied insecticides in soil. The insecticides were applied as four different type of treatments to melon crop. The treatments were (i) three periodic applications of endosulfan (Thiodan 35EC), each at 0.52 kg a.i./ha, (ii) three applications of fenitrothion (Sumithion 50WP), each at 0.35 kg a.i./ha, (iii) two applications of fenitrothion and one of endosulfan, and (iv) grower's treatment, which included applications of six different insecticides. The effect of the insecticide applications was evaluated by estimating numbers of each of the three type of insects before and within 72 hours after the applications and estimating yield of melons. All insecticide treatments reduced the populations of Aphis gossypii, but they also reduced the numbers of the benificial insects. Endosulfan was somewhat less toxic to C. carnea than the other insecticides were, since greater number of C. carnea were recorded from the plots treated with endosulfan than the other treated plots. The best yield of melons was recorded in the plots which were sprayed with fenitrothion, followed by the plots sprayed with endosulfan. and then those with grower's insecticides. Soon after the application of endosulfan the residue in the soil was 0.2 mg/kg, but it declined to less

Bt crop effects on functional guilds of non-target arthropods: a meta-analysis.

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L LaReesa Wolfenbarger

provide researchers with information to design more robust experiments and will inform the decisions of diverse stakeholders regarding the safety of transgenic insecticidal crops.

Comparative acute toxicity of neonicotinoid and pyrethroid insecticides to non-target crayfish (Procambarus clarkii) associated with rice-crayfish crop rotations.

Science.gov (United States)

Barbee, Gary C; Stout, Michael J

2009-11-01

Most insecticides used to control rice water weevil (Lissorhoptrus oryzophilus Kuscel) infestations are pyrethroids. However, pyrethroids are highly toxic to non-target crayfish associated with rice-crayfish crop rotations. One solution to the near-exclusive reliance on pyrethroids in a rice-crayfish pest management program is to incorporate neonicotinoid insecticides, which are insect specific and effective against weevils but not extremely toxic to crayfish. This study aimed to take the first step to assess neonicotinoids as alternatives to pyrethroids in rice-crayfish crop rotations by measuring the acute toxicities of three candidate neonicotinoid insecticides, clothianidin, dinotefuran and thiamethoxam, to juvenile Procambarus clarkii (Girard) crayfish and comparing them with the acute toxicities of two currently used pyrethroid insecticides, lambda-cyhalothrin and etofenprox. Neonicotinoid insecticides are at least 2-3 orders of magnitude less acutely toxic (96 h LC(50)) than pyrethroids to juvenile Procambarid crayfish: lambda-cyhalothrin (0.16 microg AI L(-1)) = etofenprox (0.29 microg AI L(-1)) > clothianidin (59 microg AI L(-1)) > thiamethoxam (967 microg AI L(-1)) > dinotefuran (2032 microg AI L(-1)). Neonicotinoid insecticides appear to be much less hazardous alternatives to pyrethroids in rice-crayfish crop rotations. Further field-level neonicotinoid acute and chronic toxicity testing with crayfish is needed. (c) 2009 Society of Chemical Industry.

Performance and cross-crop resistance of Cry1F-maize selected Spodoptera frugiperda on transgenic Bt cotton: implications for resistance management.

Science.gov (United States)

Yang, Fei; Kerns, David L; Brown, Sebe; Kurtz, Ryan; Dennehy, Tim; Braxton, Bo; Head, Graham; Huang, Fangneng

2016-06-15

Transgenic crops producing Bacillus thuringiensis (Bt) proteins have become a primary tool in pest management. Due to the intensive use of Bt crops, resistance of the fall armyworm, Spodoptera frugiperda, to Cry1F maize has occurred in Puerto Rico, Brazil, and some areas of the southeastern U.S. The sustainability of Bt crops faces a great challenge because the Cry1F-maize resistant S. frugiperda may also infest other Bt crops in multiple cropping ecosystems. Here we examined the survival and plant injury of a S. frugiperda population selected with Cry1F maize on three single-gene and five pyramided Bt cotton products. Larvae of Cry1F-susceptible (SS), -heterozygous (RS), and -resistant (RR) genotypes of S. frugiperda were all susceptible to the pyramided cotton containing Cry1Ac/Cry2Ab, Cry1Ac/Cry1F/Vip3A, Cry1Ab/Cry2Ae, or Cry1Ab/Cry2Ae/Vip3A, and the single-gene Cry2Ae cotton. Pyramided cotton containing Cry1Ac/Cry1F was effective against SS and RS, but not for RR. These findings show that the Cry1F-maize selected S. frugiperda can cause cross-crop resistance to other Bt crops expressing similar insecticidal proteins. Resistance management and pest management programs that utilize diversify mortality factors must be implemented to ensure the sustainability of Bt crops. This is especially important in areas where resistance to single-gene Bt crops is already widespread.

Bt-transgenic oilseed rape hybridization with its weedy relative, Brassica rapa.

Science.gov (United States)

Halfhill, Matthew D; Millwood, Reginald J; Raymer, Paul L; Stewart, C Neal

2002-10-01

The movement of transgenes from crops to weeds and the resulting consequences are concerns of modern agriculture. The possible generation of "superweeds" from the escape of fitness-enhancing transgenes into wild populations is a risk that is often discussed, but rarely studied. Oilseed rape, Brassica napus (L.), is a crop with sexually compatible weedy relatives, such as birdseed rape (Brassica rapa (L.)). Hybridization of this crop with weedy relatives is an extant risk and an excellent interspecific gene flow model system. In laboratory crosses, T3 lines of seven independent transformation events of Bacillus thuringiensis (Bt) oilseed rape were hybridized with two weedy accessions of B. rapa. Transgenic hybrids were generated from six of these oilseed rape lines, and the hybrids exhibited an intermediate morphology between the parental species. The Bt transgene was present in the hybrids, and the protein was synthesized at similar levels to the corresponding independent oilseed rape lines. Insect bioassays were performed and confirmed that the hybrid material was insecticidal. The hybrids were backcrossed with the weedy parent, and only half the oilseed rape lines were able to produce transgenic backcrosses. After two backcrosses, the ploidy level and morphology of the resultant plants were indistinguishable from B. rapa. Hybridization was monitored under field conditions (Tifton, GA, USA) with four independent lines of Bt oilseed rape with a crop to wild relative ratio of 1200:1. When B. rapa was used as the female parent, hybridization frequency varied among oilseed rape lines and ranged from 16.9% to 0.7%.

Response to issues on GM agriculture in Africa: Are transgenic crops safe?

OpenAIRE

Adenle, Ademola A

2011-01-01

Abstract The controversies surrounding transgenic crops, often called Genetically Modified Organisms (GMOs), call for a need to raise the level of public awareness of Genetic Modification (GM) technology in Africa. This should be accomplished by educating the public about the potential benefits and risks that may be associated with this new technology. In the last 15 years, GM crop producing countries have benefited from adoption of this new technology in the form of improved crop productivit...

Current situation of pests targeted by Bt crops in Latin America.

Science.gov (United States)

Blanco, C A; Chiaravalle, W; Dalla-Rizza, M; Farias, J R; García-Degano, M F; Gastaminza, G; Mota-Sánchez, D; Murúa, M G; Omoto, C; Pieralisi, B K; Rodríguez, J; Rodríguez-Maciel, J C; Terán-Santofimio, H; Terán-Vargas, A P; Valencia, S J; Willink, E

2016-06-01

Transgenic crops producing Bacillus thuringiensis- (Bt) insecticidal proteins (Bt crops) have provided useful pest management tools to growers for the past 20 years. Planting Bt crops has reduced the use of synthetic insecticides on cotton, maize and soybean fields in 11 countries throughout Latin America. One of the threats that could jeopardize the sustainability of Bt crops is the development of resistance by targeted pests. Governments of many countries require vigilance in measuring changes in Bt-susceptibility in order to proactively implement corrective measures before Bt-resistance is widespread, thus prolonging the usefulness of Bt crops. A pragmatic approach to obtain information on the effectiveness of Bt-crops is directly asking growers, crop consultants and academics about Bt-resistance problems in agricultural fields, first-hand information that not necessarily relies on susceptibility screens performed in laboratories. This type of information is presented in this report. Problematic pests of cotton and soybeans in five Latin American countries currently are effectively controlled by Bt crops. Growers that plant conventional (non-Bt) cotton or soybeans have to spray synthetic insecticides against multiple pests that otherwise are controlled by these Bt crops. A similar situation has been observed in six Latin American countries where Bt maize is planted. No synthetic insecticide applications are used to control corn pests because they are controlled by Bt maize, with the exception of Spodoptera frugiperda. While this insect in some countries is still effectively controlled by Bt maize, in others resistance has evolved and necessitates supplemental insecticide applications and/or the use of Bt maize cultivars that express multiple Bt proteins. Partial control of S. frugiperda in certain countries is due to its natural tolerance to the Bt bacterium. Of the 31 pests targeted and controlled by Bt crops in Latin America, only S. frugiperda has shown

Efficacy of Different Insecticides in Controlling Pollen Beetle (Meligethes aeneus F. in Rapeseed Crop

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Predrag Milovanović

2013-12-01

Full Text Available Since pollen beetle, M. aeneus, is usually controlled by insecticides, the efficacy of several compounds with different modes of action against adult beetles was studied in a threeyear field study. The selected insecticides were: three pyrethroids (lambda-cyhalothrin, alpha-cypermethrin and bifenthrin, an oganophosphate (pirimiphos-methyl, a combination of an organophosphate and a pyrethroid (chlorpyrifos + cypermethrin and a neonicotinoid (thiacloprid. The insecticides were applied at label rates to winter rapeseed crops at the moment of visible but still closed flower buds (BBCH 55-57. In all experiments, the efficacy of pyrethroids and the organophosphate ranged from 90-100%, while the efficacy of the neonicotinoid was 85-95%. Therefore, they can be recommended for control of pollen beetle in Serbia.

The Role of Transgenic Crops in the Future of Global Food and Feed

OpenAIRE

O. Škubna; H. Řezbová

2012-01-01

The paper is aimed on the problematic of biotech crops planting (GM, transgenic crops). The main aim of this paper is to analyze the trends in the main biotech crops planting groups in the sense of their use for food and feed in the future. The selected groups of biotech crops analyzed in this article are soybeans, maize (corn), cotton and rapeseed (canola). The used methods are chain and basic indexes and regression analysis of times series/ trend data - for predicting on next four years (20...

Transgenic Crops to Address Third World Hunger? A Critical Analysis

Science.gov (United States)

Rosset, Peter M.

2005-01-01

Industry and mainstream research and policy institutions often suggest that transgenic crop varieties can raise the productivity of poor third world farmers, feed the hungry, and reduce poverty. These claims are critically evaluated by examining global-hunger data, the constraints that affect the productivity of small farmers in the third world,…

Environmental risk assessments for transgenic crops producing output trait enzymes

Science.gov (United States)

Tuttle, Ann; Shore, Scott; Stone, Terry

2009-01-01

The environmental risks from cultivating crops producing output trait enzymes can be rigorously assessed by testing conservative risk hypotheses of no harm to endpoints such as the abundance of wildlife, crop yield and the rate of degradation of crop residues in soil. These hypotheses can be tested with data from many sources, including evaluations of the agronomic performance and nutritional quality of the crop made during product development, and information from the scientific literature on the mode-of-action, taxonomic distribution and environmental fate of the enzyme. Few, if any, specific ecotoxicology or environmental fate studies are needed. The effective use of existing data means that regulatory decision-making, to which an environmental risk assessment provides essential information, is not unnecessarily complicated by evaluation of large amounts of new data that provide negligible improvement in the characterization of risk, and that may delay environmental benefits offered by transgenic crops containing output trait enzymes. PMID:19924556

Perspectives on transgenic, herbicide-resistant crops in the United States almost 20 years after introduction.

Science.gov (United States)

Duke, Stephen O

2015-05-01

Herbicide-resistant crops have had a profound impact on weed management. Most of the impact has been by glyphosate-resistant maize, cotton, soybean and canola. Significant economic savings, yield increases and more efficacious and simplified weed management have resulted in widespread adoption of the technology. Initially, glyphosate-resistant crops enabled significantly reduced tillage and reduced the environmental impact of weed management. Continuous use of glyphosate with glyphosate-resistant crops over broad areas facilitated the evolution of glyphosate-resistant weeds, which have resulted in increases in the use of tillage and other herbicides with glyphosate, reducing some of the initial environmental benefits of glyphosate-resistant crops. Transgenic crops with resistance to auxinic herbicides, as well as to herbicides that inhibit acetolactate synthase, acetyl-CoA carboxylase and hydroxyphenylpyruvate dioxygenase, stacked with glyphosate and/or glufosinate resistance, will become available in the next few years. These technologies will provide additional weed management options for farmers, but will not have all of the positive effects (reduced cost, simplified weed management, lowered environmental impact and reduced tillage) that glyphosate-resistant crops had initially. In the more distant future, other herbicide-resistant crops (including non-transgenic ones), herbicides with new modes of action and technologies that are currently in their infancy (e.g. bioherbicides, sprayable herbicidal RNAi and/or robotic weeding) may affect the role of transgenic, herbicide-resistant crops in weed management. Published 2014. This article is a U.S. Government work and is in the public domain in the USA. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

Pest control and resistance management through release of insects carrying a male-selecting transgene.

Science.gov (United States)

Harvey-Samuel, Tim; Morrison, Neil I; Walker, Adam S; Marubbi, Thea; Yao, Ju; Collins, Hilda L; Gorman, Kevin; Davies, T G Emyr; Alphey, Nina; Warner, Simon; Shelton, Anthony M; Alphey, Luke

2015-07-16

Development and evaluation of new insect pest management tools is critical for overcoming over-reliance upon, and growing resistance to, synthetic, biological and plant-expressed insecticides. For transgenic crops expressing insecticidal proteins from the bacterium Bacillus thuringiensis ('Bt crops') emergence of resistance is slowed by maintaining a proportion of the crop as non-Bt varieties, which produce pest insects unselected for resistance. While this strategy has been largely successful, multiple cases of Bt resistance have now been reported. One new approach to pest management is the use of genetically engineered insects to suppress populations of their own species. Models suggest that released insects carrying male-selecting (MS) transgenes would be effective agents of direct, species-specific pest management by preventing survival of female progeny, and simultaneously provide an alternative insecticide resistance management strategy by introgression of susceptibility alleles into target populations. We developed a MS strain of the diamondback moth, Plutella xylostella, a serious global pest of crucifers. MS-strain larvae are reared as normal with dietary tetracycline, but, when reared without tetracycline or on host plants, only males will survive to adulthood. We used this strain in glasshouse-cages to study the effect of MS male P. xylostella releases on target pest population size and spread of Bt resistance in these populations. Introductions of MS-engineered P. xylostella males into wild-type populations led to rapid pest population decline, and then elimination. In separate experiments on broccoli plants, relatively low-level releases of MS males in combination with broccoli expressing Cry1Ac (Bt broccoli) suppressed population growth and delayed the spread of Bt resistance. Higher rates of MS male releases in the absence of Bt broccoli were also able to suppress P. xylostella populations, whereas either low-level MS male releases or Bt broccoli

Competitive release and outbreaks of non-target pests associated with transgenic Bt cotton.

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Zeilinger, Adam R; Olson, Dawn M; Andow, David A

2016-06-01

The adoption of transgenic Bt cotton has, in some cases, led to environmental and economic benefits through reduced insecticide use. However, the distribution of these benefits and associated risks among cotton growers and cotton-growing regions has been uneven due in part to outbreaks of non-target or secondary pests, thereby requiring the continued use of synthetic insecticides. In the southeastern USA, Bt cotton adoption has resulted in increased abundance of and damage from stink bug pests, Euschistus servus and Nezara viridula (Heteroptera: Pentatomidae). While the impact of increased stink bug abundance has been well-documented, the causes have remained unclear. We hypothesize that release from competition with Bt-susceptible target pests may drive stink bug outbreaks in Bt cotton. We first examined the evidence for competitive release of stink bugs through meta-analysis of previous studies. We then experimentally tested if herbivory by Bt-susceptible Helicoverpa zea increases stink bug leaving rates and deters oviposition on non-Bt cotton. Consistent with previous studies, we found differences in leaving rates only for E servus, but we found that both species strongly avoided ovipositing on H. zea-damaged plants. Considering all available evidence, competitive release of stink bug populations in Bt cotton likely contributes to outbreaks, though the relative importance of competitive release remains an open question. Ecological risk assessments of Bt crops and other transgenic insecticidal crops would benefit from greater understanding of the ecological mechanisms underlying non-target pest outbreaks and greater attention to indirect ecological effects more broadly.

Expression of Cry1Ab and Cry2Ab by a polycistronic transgene with a self-cleavage peptide in rice.

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Qichao Zhao

Full Text Available Insect resistance to Bacillus thuringiensis (Bt crystal protein is a major threat to the long-term use of transgenic Bt crops. Gene stacking is a readily deployable strategy to delay the development of insect resistance while it may also broaden insecticidal spectrum. Here, we report the creation of transgenic rice expressing discrete Cry1Ab and Cry2Ab simultaneously from a single expression cassette using 2A self-cleaving peptides, which are autonomous elements from virus guiding the polycistronic viral gene expression in eukaryotes. The synthetic coding sequences of Cry1Ab and Cry2Ab, linked by the coding sequence of a 2A peptide from either foot and mouth disease virus or porcine teschovirus-1, regardless of order, were all expressed as discrete Cry1Ab and Cry2Ab at high levels in the transgenic rice. Insect bioassays demonstrated that the transgenic plants were highly resistant to lepidopteran pests. This study suggested that 2A peptide can be utilized to express multiple Bt genes at high levels in transgenic crops.

Effects of Soil Water Deficit on Insecticidal Protein Expression in Boll Shells of Transgenic Bt Cotton and the Mechanism

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Xiang Zhang

2017-12-01

Full Text Available This study was conducted to investigate the effects of soil water deficit on insecticidal protein expression in boll shells of cotton transgenic for a Bt gene. In 2014, Bt cotton cultivars Sikang 1 (a conventional cultivar and Sikang 3 (a hybrid cultivar were planted in pots and five soil water content treatments were imposed at peak boll stage: 15% (G1, 35% (G2, 40% (G3, 60% (G4, and 75% field capacity (CK, respectively. Four treatments (G2, G3, G4, and CK were repeated in 2015 in the field. Results showed that the insecticidal protein content of boll shells decreased with increasing water deficit. Compared with CK, boll shell insecticidal protein content decreased significantly when soil water content was below 60% of maximum water holding capacity for Sikang 1 and Sikang 3. However, increased Bt gene expression was observed when boll shell insecticidal protein content was significantly reduced. Activity assays of key enzymes in nitrogen metabolism showed that boll shell protease and peptidase increased but nitrogen reductase and glutamic-pyruvic transaminase (GPT decreased. Insecticidal protein content exhibited significant positive correlation with nitrogen reductase and GPT activities; and significant negative correlation with protease and peptidase activities. These findings suggest that the decrease of insecticidal protein content associated with increasing water deficit was a net result of decreased synthesis and increased decomposition.

Optimum timing of insecticide applications against diamondback moth Plutella xylostella in cole crops using threshold catches in sex pheromone traps.

Science.gov (United States)

Reddy, G V; Guerrero, A

2001-01-01

Field trials were conducted in cabbage (Brassica oleracea var capitata), cauliflower (B oleracea var botrytis) and knol khol (B oleracea gongylodes) crops at two different locations in Karnataka State (India) to optimize the timing of insecticide applications to control the diamondback moth, Plutella xylostella, using sex pheromone traps. Our results indicate that applications of cartap hydrochloride as insecticide during a 12-24 h period after the pheromone traps had caught on average 8, 12 and 16 males per trap per night in cabbage, cauliflower and knol khol, respectively, were significantly more effective than regular insecticide sprays at 7, 9, 12 or 15 days after transplantation. This was demonstrated by estimation of the mean number of eggs and larvae per plant, the percentage of holes produced, as well as the marketable yield of the three crops at each location. A good correlation between the immature stages, infestation level, the estimated crop yield and the number of moths caught in pheromone traps was also found, indicating the usefulness of pheromone-based monitoring traps to predict population densities of the pest.

Transgenic crops with an improved resistance to biotic stresses. A review

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Tohidfar, M.

2015-01-01

Full Text Available Introduction. Pests, diseases and weeds (biotic stresses are significant limiting factors for crop yield and production. However, the limitations associated with conventional breeding methods necessitated the development of alternative methods for improving new varieties with higher resistance to biotic stresses. Molecular techniques have developed applicable methods for genetic transformation of a wide range of plants. Genetic engineering approach has been demonstrated to provide enormous options for the selection of the resistance genes from different sources to introduce them into plants to provide resistance against different biotic stresses. Literature. In this review, we focus on strategies to achieve the above mentioned objectives including expression of insecticidal, antifungal, antibacterial, antiviral resistance and herbicide detoxification for herbicide resistance. Conclusion. Regardless of the concerns about commercialization of products from genetically modified (GM crops resistant to biotic stresses, it is observed that the cultivation area of these crops is growing fast each year. Considering this trend, it is expected that production and commercialization of GM crops resistant to biotic stresses will continue to increase but will also extend to production of crops resistant to abiotic stresses (e.g. drought, salinity, etc. in a near future.

Increasing plant diversity with border crops reduces insecticide use and increases crop yield in urban agriculture.

Science.gov (United States)

Wan, Nian-Feng; Cai, You-Ming; Shen, Yan-Jun; Ji, Xiang-Yun; Wu, Xiang-Wen; Zheng, Xiang-Rong; Cheng, Wei; Li, Jun; Jiang, Yao-Pei; Chen, Xin; Weiner, Jacob; Jiang, Jie-Xian; Nie, Ming; Ju, Rui-Ting; Yuan, Tao; Tang, Jian-Jun; Tian, Wei-Dong; Zhang, Hao; Li, Bo

2018-05-24

Urban agriculture is making an increasing contribution to food security in large cities around the world. The potential contribution of biodiversity to ecological intensification in urban agricultural systems has not been investigated. We present monitoring data collected from rice fields in 34 community farms in mega-urban Shanghai, China, from 2001 to 2015, and show that the presence of a border crop of soybeans and neighboring crops (maize, eggplant and Chinese cabbage), both without weed control, increased invertebrate predator abundance, decreased the abundance of pests and dependence on insecticides, and increased grain yield and economic profits. Two 2 year randomized experiments with the low and high diversity practices in the same locations confirmed these results. Our study shows that diversifying farming practices can make an important contribution to ecological intensification and the sustainable use of associated ecosystem services in an urban ecosystem. © 2018, Wan et al.

Gm crops: between biological risk and environmental and economic benefits

International Nuclear Information System (INIS)

Chaparro Giraldo, Alejandro

2011-01-01

The transgenic crops were the result of the application of recombinant DNA technology in agriculture. These crops were developed by transfer of foreign genes (transgenes) from any biological origin (animal, plant, microbial, viral) to the genome of cultivated species of plants. The crops genetically modified (GM) have been used in the world since 1996; up to December 2010 they counted to a billion hectares planted throughout the period. In just the past year 2010 148 million hectares were planted, grown by 15.4 million farmers in 29 countries. GM crops that are used in global agriculture are mainly soybean, cotton, corn and canola, which express transgenes derived from bacteria, and confer resistance to lepidopteron insects (ILR) or herbicide tolerance (HT; glyphosate and glufosinate ammonium). the first transgenic varieties containing only a single transgene, or simple event, while the current varieties express several transgenes, or stacked, conferring resistance to different species of Lepidoptera and coleopteran insects and tolerance to two different herbicides. In 2010 were planted in Colombia, 18.874 hectares of GM cotton, 16.793 hectares of GM corn, and 4 hectares of GM carnations and GM roses. GM corn and GM cotton were planted in Sucre, Cesar, Cordoba, Huila and Tolima. GM corn was planted in Antioquia, Valle del Cauca, Meta, Cundinamarca and Santander. Carnations and roses were planted in Cundinamarca. GM maize and GM cotton expressing ILR and HT features, as simple events or stacked. In the case of GM carnation and GM roses, these genotypes that express the color blue. Academia has tried to organize the debate on the adoption of GM crops around the analysis of biological risks and environmental vs environmental and economic benefits. Biological hazards are defined by the possible negative effects on human consumers or negative effects on the environment. The environmental benefits are related to reduce use of agrochemicals (insecticides and herbicides

Field-Evolved Mode 1 Resistance of the Fall Armyworm to Transgenic Cry1Fa-Expressing Corn Associated with Reduced Cry1Fa Toxin Binding and Midgut Alkaline Phosphatase Expression

Science.gov (United States)

Jakka, Siva R. K.; Gong, Liang; Hasler, James; Banerjee, Rahul; Sheets, Joel J.; Narva, Kenneth; Blanco, Carlos A.

2015-01-01

Insecticidal protein genes from the bacterium Bacillus thuringiensis (Bt) are expressed by transgenic Bt crops (Bt crops) for effective and environmentally safe pest control. The development of resistance to these insecticidal proteins is considered the most serious threat to the sustainability of Bt crops. Resistance in fall armyworm (Spodoptera frugiperda) populations from Puerto Rico to transgenic corn producing the Cry1Fa insecticidal protein resulted, for the first time in the United States, in practical resistance, and Bt corn was withdrawn from the local market. In this study, we used a field-collected Cry1Fa corn-resistant strain (456) of S. frugiperda to identify the mechanism responsible for field-evolved resistance. Binding assays detected reduced Cry1Fa, Cry1Ab, and Cry1Ac but not Cry1Ca toxin binding to midgut brush border membrane vesicles (BBMV) from the larvae of strain 456 compared to that from the larvae of a susceptible (Ben) strain. This binding phenotype is descriptive of the mode 1 type of resistance to Bt toxins. A comparison of the transcript levels for putative Cry1 toxin receptor genes identified a significant downregulation (>90%) of a membrane-bound alkaline phosphatase (ALP), which translated to reduced ALP protein levels and a 75% reduction in ALP activity in BBMV from 456 compared to that of Ben larvae. We cloned and heterologously expressed this ALP from susceptible S. frugiperda larvae and demonstrated that it specifically binds with Cry1Fa toxin. This study provides a thorough mechanistic description of field-evolved resistance to a transgenic Bt crop and supports an association between resistance and reduced Cry1Fa toxin binding and levels of a putative Cry1Fa toxin receptor, ALP, in the midguts of S. frugiperda larvae. PMID:26637593

COMPARATIVE EFFICACY OF SYNTHETIC AND BOTANICAL INSECTICIDES AGAINST SUCKING INSECT PEST AND THEIR NATURAL ENEMIES ON COTTON CROP

OpenAIRE

M. A. Baker; A. H. Makhdum; M. Nasir; A. Imran; A. Ahmad; F. Tufail

2016-01-01

The Synthetic and botanical insecticides are relatively safer for environment and beneficial insects. The study was conducted in Rahim Yar Khan during the cotton cropping season 2014 to evaluate the comparative efficacy of two Synthetic insecticides i.e. Nitenpyram (Jasper 10% SL) and Pyriproxyfen (Bruce 10.8% EC) and two botanical extracts of Calotropic procera and Azadirachta indica, against sucking insect pest complex of cotton and their natural enemies. Upon reaching economic thresholds, ...

SPATIAL DIMENSION OF EXTERNALITIES AND THE COASE THEOREM: IMPLICATIONS FOR CO-EXISTENCE OF TRANSGENIC CROPS

OpenAIRE

Beckmann, Volker; Wesseler, Justus

2005-01-01

"No form of agriculture should be excluded in the EU." Many observers see this recent statement by European agricultural commissioner Franz Fischler as a clear signal towards a nearby lifting of the quasi EU moratorium on transgenic crops (or GMs for short) launched in 1998 (European Commission 2002). One of the last obstacles towards lifting the moratorium, however, is the problem of coexistence. How can GM-crops and non-GM-crops coexist? Since the European Environmental Agency published its...

Errors in logic and statistics plague a meta-analysis

Science.gov (United States)

The non-target effects of transgenic insecticidal crops has been a topic of debate for over a decade and many laboratory and field studies have addressed the issue in numerous countries. In 2009 Lovei et al. (Transgenic Insecticidal Crops and Natural Enemies: A Detailed Review of Laboratory Studies)...

The policy chicken and the science egg. Has applied ecology failed the transgenic crops debate?

Science.gov (United States)

Gray, A J

2014-12-01

Ecology has a long history of research relevant to and impacting on real-world issues. Nonetheless problems of communication remain between policy-makers and scientists because they tend to work at different levels of generality (policy deals with broad issues, science prefers specific questions), and complexity (policy-makers want simple answers, ecologists tend to offer multi-factorial solutions) and to different timescales (policy-makers want answers tomorrow, ecologists always seem to want more time). These differences are not unique to the debate about the cultivation of transgenic crops. Research on gene flow is used to illustrate how science and policy are intimately bound together in a value-laden, iterative and messy process unlike that characterised by the 'encounter problem-do science-make policy' model. It also demonstrates how the gap between science and policy is often characterised by value-laden language. Scientists involved in ERA for transgenic crops may find their engagement with policy- and decision-makers clouded by misunderstanding about what one should expect from the other. Not the least of these, that science can define harm, is explored in a discussion of the U.K. Farm Scale Evaluations of herbicide-tolerant GM crops. The varied responses to these extensive trials highlight the problems of linking specific scientific experiments with broad policy objectives. The problems of applied ecology in the transgenic crops debate are not unique but may differ from other areas of environmental policy in the intense politicisation of the debate, the emphasis on assessment of risk and the particularly broad policy objectives.

Neonicotinoid Insecticides Alter Induced Defenses and Increase Susceptibility to Spider Mites in Distantly Related Crop Plants

Science.gov (United States)

Szczepaniec, Adrianna; Raupp, Michael J.; Parker, Roy D.; Kerns, David; Eubanks, Micky D.

2013-01-01

Background Chemical suppression of arthropod herbivores is the most common approach to plant protection. Insecticides, however, can cause unintended, adverse consequences for non-target organisms. Previous studies focused on the effects of pesticides on target and non-target pests, predatory arthropods, and concomitant ecological disruptions. Little research, however, has focused on the direct effects of insecticides on plants. Here we demonstrate that applications of neonicotinoid insecticides, one of the most important insecticide classes worldwide, suppress expression of important plant defense genes, alter levels of phytohormones involved in plant defense, and decrease plant resistance to unsusceptible herbivores, spider mites Tetranychus urticae (Acari: Tetranychidae), in multiple, distantly related crop plants. Methodology/Principal Findings Using cotton (Gossypium hirsutum), corn (Zea mays) and tomato (Solanum lycopersicum) plants, we show that transcription of phenylalanine amonia lyase, coenzyme A ligase, trypsin protease inhibitor and chitinase are suppressed and concentrations of the phytohormone OPDA and salicylic acid were altered by neonicotinoid insecticides. Consequently, the population growth of spider mites increased from 30% to over 100% on neonicotinoid-treated plants in the greenhouse and by nearly 200% in the field experiment. Conclusions/Significance Our findings are important because applications of neonicotinoid insecticides have been associated with outbreaks of spider mites in several unrelated plant species. More importantly, this is the first study to document insecticide-mediated disruption of plant defenses and link it to increased population growth of a non-target herbivore. This study adds to growing evidence that bioactive agrochemicals can have unanticipated ecological effects and suggests that the direct effects of insecticides on plant defenses should be considered when the ecological costs of insecticides are evaluated. PMID

The myth of natural barriers. Is transgene introgression by genetically modified crops an environmental risk?

Science.gov (United States)

Guarnieri, Vincenzo; Benessia, Alice; Camino, Elena; Barbiero, Giuseppe

2008-01-01

Genetically modified (GM) crops under open field conditions are a complex and controversial issue. Ecologists are discussing about the possibility that a transgene belonging to GM plants could spread to native populations through a process known as introgression the stable incorporation of a gene in the host genome able to generate a differentiated population. The ecological consequences of a transgene introgression in plants or bacteria are not yet well understood, but could be significant. In this critical review we consider vertical and horizontal introgression. We analyse the biochemical and genetic constraints, and environmental factors that limit the possibility of transgene spread; meanwhile we show cases in which the natural barriers are overcome. Then we discuss the overall management of GM crops, noting the shortcomings and approximations of risk assessment based on linear thinking typical of the biomolecular approach. Finally we suggest to explicitly weight facts together with values and we encourage the undertaking of an ecological perspective, encompassing the complexity of (non-linear) relations between organisms and the environment.

Evaluation of Insecticides and Agril Polyester Cover against Whitefly (Bemisia Tabaci Gennadius in Tomato Crops

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K.M. Azam

1996-01-01

Full Text Available Field experiments were conducted on tomato crops over a two year period to evaluate the efficacy of six insecticides, viz., triazophos, phosphamidon, dimethoate, buprofezin and Aflix (endosulfan + dimethoate each at 0.05% and Repelin (plant insecticide at 1% concentration along With a cultural treatment by covering the plants with Agril (a polyester material for the control of whitefly, Bemisia tabaci. The insecticides were applied eight times at weekly interval immediately after transplantation. The whitefly eggs,  nymphal population counts and the per cent incidence of tomato leaf curl virus (TLCV were recorded every week for eight weeks in all the treatments including untreated control. The incidence of whitefly was more severe in the second year (i.e, 1992-93 as compared to the previous season. Among the various treatments, the Agril cover, a newly introduced cultural practice, recorded the least incidence of whitefly and of TLCV. The average of counts of eggs were 0.0 and 5.47 and of nymphs 0.54 and 0.58 per 10 leaflets and TLCV were 4.32% and 4.76% in Agril cover treatment during the first and second year, respectively. Among the insecticides tested only Aflix recorded less incidence of the pest, being 3.46 and 30.4 eggs per 10 leaflets and 0.94 and 5.34 nymphs per 10 leaflets during the two years of study, respectively. The other treatments were less effective in reducing pest and disease incidence. The crop under Agril-cover recorded the maximum yield of 34.57 and 26.15 t/ha of tomatoes as compared to 16.48 and 10.82 t/ha in control during the first and second year, respectively.

Biosafety assessment of transgenic Bt cotton on model animals

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Sadia Bano

2016-05-01

Full Text Available Abstract Background: To know the effects of transgenic crops on soil microorganisms, animals and other expected hazards due to the introduction of GM crops into the environment is critical both scientifically and environmentally. The work was conducted to study the effect of insecticidal Bt protein on Rats and Earthworms. Methods: For this purpose, animals like rat and soil organisms like Earthworm were selected. Rats were selected on the basis of its 95% homology on genomic, cellular and enzymatic level with human while earthworm were preferred on the basis of their direct contact with soil to evaluate the impact of Bt (Cry1AC crop field soil on earthworm, secreted by root exudates of Bt cotton. Several physical, molecular, biochemical and histological analyses were performed on both Rats/Earthworms fed on standard diet (control group as well containing Bt protein (experimental group. Results: Molecular analyses such as immune Dot blot, SDS-PAGE, ELISA and PCR, confirmed the absence of Cry1Ac protein in blood and urine samples of rats, which were fed with Bt protein in their diet. Furthermore, histological studies showed that there was no difference in cellular architecture in liver, heart, kidney and intestine of Bt and non-Bt diet fed rats. To see the effect of Bt on earthworm two different groups were studied, one with transgenic plant field soil supplemented with grinded leaves of cotton and second group with non-Bt field soil. Conclusions: No lethal effects of transgenic Bt protein on the survival of earthworm and rats were observed. Bradford assay, Dipstick assay ELISA demonstrated the absence of Cry1Ac protein in the mid-gut epithelial tissue of earthworm. The results of present study will be helpful in successful deployment and commercial release of genetically modified crop in Pakistan.

Increasing public understanding of transgenic crops through the World Wide Web.

Science.gov (United States)

Byrne, Patrick F; Namuth, Deana M; Harrington, Judy; Ward, Sarah M; Lee, Donald J; Hain, Patricia

2002-07-01

Transgenic crops among the most controversial "science and society" issues of recent years. Because of the complex techniques involved in creating these crops and the polarized debate over their risks and beliefs, a critical need has arisen for accessible and balanced information on this technology. World Wide Web sites offer several advantages for disseminating information on a fast-changing technical topic, including their global accessibility; and their ability to update information frequently, incorporate multimedia formats, and link to networks of other sites. An alliance between two complementary web sites at Colorado State University and the University of Nebraska-Lincoln takes advantage of the web environment to help fill the need for public information on crop genetic engineering. This article describes the objectives and features of each site. Viewership data and other feedback have shown these web sites to be effective means of reaching public audiences on a complex scientific topic.

COMPARATIVE EFFICACY OF SYNTHETIC AND BOTANICAL INSECTICIDES AGAINST SUCKING INSECT PEST AND THEIR NATURAL ENEMIES ON COTTON CROP

Directory of Open Access Journals (Sweden)

M. A. Baker

2016-08-01

Full Text Available The Synthetic and botanical insecticides are relatively safer for environment and beneficial insects. The study was conducted in Rahim Yar Khan during the cotton cropping season 2014 to evaluate the comparative efficacy of two Synthetic insecticides i.e. Nitenpyram (Jasper 10% SL and Pyriproxyfen (Bruce 10.8% EC and two botanical extracts of Calotropic procera and Azadirachta indica, against sucking insect pest complex of cotton and their natural enemies. Upon reaching economic thresholds, the recommended field doses of all the insecticides were applied on cotton cultivar MNH-886. Data against sucking pests and their natural enemies was recorded 24 hours prior to insecticidal application and then 24, 48, 72 and 96 hours after insecticidal application. Results revealed that Nitenpyram was much toxic against sucking pests followed by Pyriproxyfen as compared to two botanical extracts. On the other hand, the synthetic insecticides did not prove safer for natural enemies as compared to botanical extracts. It was concluded that as an Integrated Pest Management (IPM strategy, botanical extracts can be used at low infestation levels so that ecosystem service of biological control may be sustained.

The food and environmental safety of Bt crops

Science.gov (United States)

Koch, Michael S.; Ward, Jason M.; Levine, Steven L.; Baum, James A.; Vicini, John L.; Hammond, Bruce G.

2015-01-01

Bacillus thuringiensis (Bt) microbial pesticides have a 50-year history of safety in agriculture. Cry proteins are among the active insecticidal ingredients in these pesticides, and genes coding for Cry proteins have been introduced into agricultural crops using modern biotechnology. The Cry gene sequences are often modified to enable effective expression in planta and several Cry proteins have been modified to increase biological activity against the target pest(s). Additionally, the domains of different but structurally conserved Cry proteins can be combined to produce chimeric proteins with enhanced insecticidal properties. Environmental studies are performed and include invertebrates, mammals, and avian species. Mammalian studies used to support the food and feed safety assessment are also used to support the wild mammal assessment. In addition to the NTO assessment, the environmental assessment includes a comparative assessment between the Bt crop and the appropriate conventional control that is genetically similar but lacks the introduced trait to address unintended effects. Specific phenotypic, agronomic, and ecological characteristics are measured in the Bt crop and the conventional control to evaluate whether the introduction of the insect resistance has resulted in any changes that might cause ecological harm in terms of altered weed characteristics, susceptibility to pests, or adverse environmental impact. Additionally, environmental interaction data are collected in field experiments for Bt crop to evaluate potential adverse effects. Further to the agronomic and phenotypic evaluation, potential movement of transgenes from a genetically modified crop plants into wild relatives is assessed for a new pest resistance gene in a new crop. This review summarizes the evidence for safety of crops containing Cry proteins for humans, livestock, and other non-target organisms. PMID:25972882

The food and environmental safety of Bt crops.

Science.gov (United States)

Koch, Michael S; Ward, Jason M; Levine, Steven L; Baum, James A; Vicini, John L; Hammond, Bruce G

2015-01-01

Bacillus thuringiensis (Bt) microbial pesticides have a 50-year history of safety in agriculture. Cry proteins are among the active insecticidal ingredients in these pesticides, and genes coding for Cry proteins have been introduced into agricultural crops using modern biotechnology. The Cry gene sequences are often modified to enable effective expression in planta and several Cry proteins have been modified to increase biological activity against the target pest(s). Additionally, the domains of different but structurally conserved Cry proteins can be combined to produce chimeric proteins with enhanced insecticidal properties. Environmental studies are performed and include invertebrates, mammals, and avian species. Mammalian studies used to support the food and feed safety assessment are also used to support the wild mammal assessment. In addition to the NTO assessment, the environmental assessment includes a comparative assessment between the Bt crop and the appropriate conventional control that is genetically similar but lacks the introduced trait to address unintended effects. Specific phenotypic, agronomic, and ecological characteristics are measured in the Bt crop and the conventional control to evaluate whether the introduction of the insect resistance has resulted in any changes that might cause ecological harm in terms of altered weed characteristics, susceptibility to pests, or adverse environmental impact. Additionally, environmental interaction data are collected in field experiments for Bt crop to evaluate potential adverse effects. Further to the agronomic and phenotypic evaluation, potential movement of transgenes from a genetically modified crop plants into wild relatives is assessed for a new pest resistance gene in a new crop. This review summarizes the evidence for safety of crops containing Cry proteins for humans, livestock, and other non-target organisms.

The Food and Environmental Safety of Bt Crops

Directory of Open Access Journals (Sweden)

Michael Stephen Koch

2015-04-01

Full Text Available Bt (Bacillus thuringiensis microbial pesticides have a 50-year history of safe use in agriculture. Cry proteins are among the active insecticidal ingredients in these pesticides, and genes coding for Cry proteins have been introduced into agricultural crops using modern biotechnology. The Cry gene sequences are often modified to enable effective expression in planta and several Cry proteins have been modified to increase biological activity against the target pest(s. Additionally, the domains of different but structurally conserved Cry proteins can be combined to produce chimeric proteins with enhanced insecticidal properties. Environmental studies are performed and include invertebrates, mammals and avian species. Mammalian studies used to support the food and feed safety assessment are also used to support the wild mammal assessment. In addition to the NTO assessment, the environmental assessment includes a comparative assessment between the Bt crop and the appropriate conventional control that is genetically similar but lacks the introduced trait to address unintended effects. Specific phenotypic, agronomic, and ecological characteristics are measured in the Bt crop and the conventional control to evaluate whether the introduction of the insect resistance has resulted in any changes that might cause ecological harm in terms of altered weed characteristics, susceptibility to pests, or adverse environmental impact. Additionally, environmental interaction data are collected in field experiments for Bt crop to evaluate potential adverse effects. Further to the agronomic and phenotypic evaluation, potential movement of transgenes from a genetically modified crop plants into wild relatives is assessed for a new pest resistance gene in a new crop. This review summarizes the evidence for safety of crops containing Cry proteins for humans, livestock, and other non-target organisms.

Plastid transformation in the monocotyledonous cereal crop, rice (Oryza sativa) and transmission of transgenes to their progeny.

Science.gov (United States)

Lee, Sa Mi; Kang, Kyungsu; Chung, Hyungsup; Yoo, Soon Hee; Xu, Xiang Ming; Lee, Seung-Bum; Cheong, Jong-Joo; Daniell, Henry; Kim, Minkyun

2006-06-30

The plastid transformation approach offers a number of unique advantages, including high-level transgene expression, multi-gene engineering, transgene containment, and a lack of gene silencing and position effects. The extension of plastid transformation technology to monocotyledonous cereal crops, including rice, bears great promise for the improvement of agronomic traits, and the efficient production of pharmaceutical or nutritional enhancement. Here, we report a promising step towards stable plastid transformation in rice. We produced fertile transplastomic rice plants and demonstrated transmission of the plastid-expressed green fluorescent protein (GFP) and aminoglycoside 3'-adenylyltransferase genes to the progeny of these plants. Transgenic chloroplasts were determined to have stably expressed the GFP, which was confirmed by both confocal microscopy and Western blot analyses. Although the produced rice plastid transformants were found to be heteroplastomic, and the transformation efficiency requires further improvement, this study has established a variety of parameters for the use of plastid transformation technology in cereal crops.

Plastid Transformation in the Monocotyledonous Cereal Crop, Rice (Oryza sativa) and Transmission of Transgenes to Their Progeny

OpenAIRE

Lee, Sa Mi; Kang, Kyungsu; Chung, Hyunsup; Yoo, Soon Hee; Xu, Xiang Ming; Lee, Seung-Bum; Cheong, Jong-Joo; Daniell, Henry; Kim, Minkyun

2006-01-01

The plastid transformation approach offers a number of unique advantages, including high-level transgene expression, multi-gene engineering, transgene containment, and a lack of gene silencing and position effects. The extension of plastid transformation technology to monocotyledonous cereal crops, including rice, bears great promise for the improvement of agronomic traits, and the efficient production of pharmaceutical or nutritional enhancement. Here, we report a promising step towards stab...

Distribution and Potential Impact of Feral Cotton on the ...

African Journals Online (AJOL)

Transgenic Bt cotton with insecticidal properties presents a potential solution to the bollworm infestation in Tanzania. However, concerns associated with transgenic crops viz.; transgene flow to wild and feral relatives, increased potential for resistance evolution, need to be addressed prior to adoption of any transgenic crop.

Genetic load and transgenic mitigating genes in transgenic Brassica rapa (field mustard × Brassica napus (oilseed rape hybrid populations

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Warwick Suzanne I

2009-10-01

Full Text Available Abstract Background One theoretical explanation for the relatively poor performance of Brassica rapa (weed × Brassica napus (crop transgenic hybrids suggests that hybridization imparts a negative genetic load. Consequently, in hybrids genetic load could overshadow any benefits of fitness enhancing transgenes and become the limiting factor in transgenic hybrid persistence. Two types of genetic load were analyzed in this study: random/linkage-derived genetic load, and directly incorporated genetic load using a transgenic mitigation (TM strategy. In order to measure the effects of random genetic load, hybrid productivity (seed yield and biomass was correlated with crop- and weed-specific AFLP genomic markers. This portion of the study was designed to answer whether or not weed × transgenic crop hybrids possessing more crop genes were less competitive than hybrids containing fewer crop genes. The effects of directly incorporated genetic load (TM were analyzed through transgene persistence data. TM strategies are proposed to decrease transgene persistence if gene flow and subsequent transgene introgression to a wild host were to occur. Results In the absence of interspecific competition, transgenic weed × crop hybrids benefited from having more crop-specific alleles. There was a positive correlation between performance and number of B. napus crop-specific AFLP markers [seed yield vs. marker number (r = 0.54, P = 0.0003 and vegetative dry biomass vs. marker number (r = 0.44, P = 0.005]. However under interspecific competition with wheat or more weed-like conditions (i.e. representing a situation where hybrid plants emerge as volunteer weeds in subsequent cropping systems, there was a positive correlation between the number of B. rapa weed-specific AFLP markers and seed yield (r = 0.70, P = 0.0001, although no such correlation was detected for vegetative biomass. When genetic load was directly incorporated into the hybrid genome, by inserting a

Botanical Insecticides in Plant Protection

OpenAIRE

Grdiša, Martina; Gršić, Kristina

2013-01-01

Botanical insecticides are natural compounds with insecticidal properties and their use in crop protection is as old as agricultural practice. Although they have been in use for over one hundred years, the advent of synthetic insecticides has unfortunately displaced their use today. Due to fast action, low cost, easy application and efficiency against a wide range of harmful species, synthetic insecticides have become an important part of pest management in modern agricultural systems....

Transgenic crops coping with water scarcity.

Science.gov (United States)

Cominelli, Eleonora; Tonelli, Chiara

2010-11-30

Water scarcity is a serious problem that will be exacerbated by global climate change. Massive quantities of water are used in agriculture, and abiotic stresses, especially drought and increased salinity, are primary causes of crop loss worldwide. Various approaches may be adopted to consume less water in agriculture, one of them being the development of plants that use less water yet maintain high yields in conditions of water scarcity. In recent years several molecular networks concerned with stress perception, signal transduction and stress responses in plants have been elucidated. Consequently, engineering some of the genes involved in these mechanisms promises to enhance plant tolerance to stresses and in particular increase their water use efficiency. Here we review the various approaches used so far to produce transgenic plants having improved tolerance to abiotic stresses, and discuss criteria for choosing which genes to work on (functional and regulatory genes) and which gene expression promoters (constitutive, inducible, and cell-specific) have been used to obtain successful results. Copyright © 2010 Elsevier B.V. All rights reserved.

The contribution of agricultural insecticide use to increasing insecticide resistance in African malaria vectors.

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Reid, Molly C; McKenzie, F Ellis

2016-02-19

The fight against malaria is increasingly threatened by failures in vector control due to growing insecticide resistance. This review examines the recent primary research that addresses the putative relationship between agricultural insecticide use and trends in insecticide resistance. To do so, descriptive evidence offered by the new research was categorized, and additional factors that impact the relationship between agricultural insecticide use and observed insecticide resistance in malaria vectors were identified. In 23 of the 25 relevant recent publications from across Africa, higher resistance in mosquito populations was associated with agricultural insecticide use. This association appears to be affected by crop type, farm pest management strategy and urban development.

Lectin cDNA and transgenic plants derived therefrom

Science.gov (United States)

Raikhel, Natasha V.

2000-10-03

Transgenic plants containing cDNA encoding Gramineae lectin are described. The plants preferably contain cDNA coding for barley lectin and store the lectin in the leaves. The transgenic plants, particularly the leaves exhibit insecticidal and fungicidal properties.

Biotechnology: herbicide-resistant crops

Science.gov (United States)

Transgenic, herbicide-resistant (HR) crops are planted on about 80% of the land covered by transgenic crops. More than 90% of HR crios are glyphosate-resistant (GR) crops, the others being resistant to glufosinate. The wide-scale adoption of HR crops, largely for economic reasons, has been the mos...

Transgenic plants expressing the AaIT/GNA fusion protein show increased resistance and toxicity to both chewing and sucking pests.

Science.gov (United States)

Liu, Shu-Min; Li, Jie; Zhu, Jin-Qi; Wang, Xiao-Wei; Wang, Cheng-Shu; Liu, Shu-Sheng; Chen, Xue-Xin; Li, Sheng

2016-04-01

The adoption of pest-resistant transgenic plants to reduce yield losses and decrease pesticide use has been successful. To achieve the goal of controlling both chewing and sucking pests in a given transgenic plant, we generated transgenic tobacco, Arabidopsis, and rice plants expressing the fusion protein, AaIT/GNA, in which an insecticidal scorpion venom neurotoxin (Androctonus australis toxin, AaIT) is fused to snowdrop lectin (Galanthus nivalis agglutinin, GNA). Compared with transgenic tobacco and Arabidopsis plants expressing AaIT or GNA, transgenic plants expressing AaIT/GNA exhibited increased resistance and toxicity to one chewing pest, the cotton bollworm, Helicoverpa armigera. Transgenic tobacco and rice plants expressing AaIT/GNA showed increased resistance and toxicity to two sucking pests, the whitefly, Bemisia tabaci, and the rice brown planthopper, Nilaparvata lugens, respectively. Moreover, in the field, transgenic rice plants expressing AaIT/GNA exhibited a significant improvement in grain yield when infested with N. lugens. This study shows that expressing the AaIT/GNA fusion protein in transgenic plants can be a useful approach for controlling pests, particularly sucking pests which are not susceptible to the toxin in Bt crops. © 2015 Institute of Zoology, Chinese Academy of Sciences.

Large-scale deployment of seed treatments has driven rapid increase in use of neonicotinoid insecticides and preemptive pest management in US field crops.

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Douglas, Margaret R; Tooker, John F

2015-04-21

Neonicotinoids are the most widely used class of insecticides worldwide, but patterns of their use in the U.S. are poorly documented, constraining attempts to understand their role in pest management and potential nontarget effects. We synthesized publicly available data to estimate and interpret trends in neonicotinoid use since their introduction in 1994, with a special focus on seed treatments, a major use not captured by the national pesticide-use survey. Neonicotinoid use increased rapidly between 2003 and 2011, as seed-applied products were introduced in field crops, marking an unprecedented shift toward large-scale, preemptive insecticide use: 34-44% of soybeans and 79-100% of maize hectares were treated in 2011. This finding contradicts recent analyses, which concluded that insecticides are used today on fewer maize hectares than a decade or two ago. If current trends continue, neonicotinoid use will increase further through application to more hectares of soybean and other crop species and escalation of per-seed rates. Alternatively, our results, and other recent analyses, suggest that carefully targeted efforts could considerably reduce neonicotinoid use in field crops without yield declines or economic harm to farmers, reducing the potential for pest resistance, nontarget pest outbreaks, environmental contamination, and harm to wildlife, including pollinator species.

Comparison of nutritional value of transgenic peanut expressing bar and rcg3 genes with non-transgenic counterparts

International Nuclear Information System (INIS)

Robab, U.E.; )

2014-01-01

The transgenic peanut plants expressing bar and rcg3 genes were subjected to assessment of any change in nutritional value of the crop at various locations. The protein and fat contents of transgenic lines were compared with the non-transgenic parent varieties. Protein content in the transgenic lines was higher as compared to that in non-transgenic counterparts and differences among locations for fat and protein content were significant. No differences among fatty acids were recorded for genes, events and locations. Irrespective of small differences, all the values were in range described for this crop and transgenic lines appeared to be substantially equivalent to non-transgenic parent varieties. (author)

Enhanced whitefly resistance in transgenic tobacco plants expressing double stranded RNA of v-ATPase A gene.

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Thakur, Nidhi; Upadhyay, Santosh Kumar; Verma, Praveen C; Chandrashekar, Krishnappa; Tuli, Rakesh; Singh, Pradhyumna K

2014-01-01

Expression of double strand RNA (dsRNA) designed against important insect genes in transgenic plants have been shown to give protection against pests through RNA interference (RNAi), thus opening the way for a new generation of insect-resistant crops. We have earlier compared the efficacy of dsRNAs/siRNAs, against a number of target genes, for interference in growth of whitefly (Bemisia tabaci) upon oral feeding. The v-ATPase subunit A (v-ATPaseA) coding gene was identified as a crucial target. We now report the effectiveness of transgenic tobacco plants expressing siRNA to silence v-ATPaseA gene expression for the control of whitefly infestation. Transgenic tobacco lines were developed for the expression of long dsRNA precursor to make siRNA and knock down the v-ATPaseA mRNA in whitefly. Molecular analysis and insecticidal properties of the transgenic plants established the formation of siRNA targeting the whitefly v-ATPaseA, in the leaves. The transcript level of v-ATPaseA in whiteflies was reduced up to 62% after feeding on the transgenic plants. Heavy infestation of whiteflies on the control plants caused significant loss of sugar content which led to the drooping of leaves. The transgenic plants did not show drooping effect. Host plant derived pest resistance was achieved against whiteflies by genetic transformation of tobacco which generated siRNA against the whitefly v-ATPaseA gene. Transgenic tobacco lines expressing dsRNA of v-ATPaseA, delivered sufficient siRNA to whiteflies feeding on them, mounting a significant silencing response, leading to their mortality. The transcript level of the target gene was reduced in whiteflies feeding on transgenic plants. The strategy can be taken up for genetic engineering of plants to control whiteflies in field crops.

Enhanced whitefly resistance in transgenic tobacco plants expressing double stranded RNA of v-ATPase A gene.

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Nidhi Thakur

Full Text Available BACKGROUND: Expression of double strand RNA (dsRNA designed against important insect genes in transgenic plants have been shown to give protection against pests through RNA interference (RNAi, thus opening the way for a new generation of insect-resistant crops. We have earlier compared the efficacy of dsRNAs/siRNAs, against a number of target genes, for interference in growth of whitefly (Bemisia tabaci upon oral feeding. The v-ATPase subunit A (v-ATPaseA coding gene was identified as a crucial target. We now report the effectiveness of transgenic tobacco plants expressing siRNA to silence v-ATPaseA gene expression for the control of whitefly infestation. METHODOLOGY/PRINCIPAL FINDINGS: Transgenic tobacco lines were developed for the expression of long dsRNA precursor to make siRNA and knock down the v-ATPaseA mRNA in whitefly. Molecular analysis and insecticidal properties of the transgenic plants established the formation of siRNA targeting the whitefly v-ATPaseA, in the leaves. The transcript level of v-ATPaseA in whiteflies was reduced up to 62% after feeding on the transgenic plants. Heavy infestation of whiteflies on the control plants caused significant loss of sugar content which led to the drooping of leaves. The transgenic plants did not show drooping effect. CONCLUSIONS/SIGNIFICANCE: Host plant derived pest resistance was achieved against whiteflies by genetic transformation of tobacco which generated siRNA against the whitefly v-ATPaseA gene. Transgenic tobacco lines expressing dsRNA of v-ATPaseA, delivered sufficient siRNA to whiteflies feeding on them, mounting a significant silencing response, leading to their mortality. The transcript level of the target gene was reduced in whiteflies feeding on transgenic plants. The strategy can be taken up for genetic engineering of plants to control whiteflies in field crops.

Transgene mobilization and regulatory uncertainty for non-GE fruit products of transgenic rootstocks.

Science.gov (United States)

Haroldsen, Victor M; Chi-Ham, Cecilia L; Bennett, Alan B

2012-10-31

Genetically engineered (GE) rootstocks may offer some advantages for biotechnology applications especially in woody perennial crops such as grape or walnut. Transgrafting combines horticultural grafting practices with modern GE methods for crop improvement. Here, a non-GE conventional scion (upper stem portion) is grafted onto a transgenic GE rootstock. Thus, the scion does not contain the genetic modification present in the rootstock genome. We examined transgene presence in walnut and tomato GE rootstocks and non-GE fruit-bearing scions. Mobilization of transgene DNA, protein, and mRNA across the graft was not detected. Though transgenic siRNA mobilization was not observed in grafted tomatoes or walnut scions, transgenic siRNA signal was detected in walnut kernels. Prospective benefits from transgrafted plants include minimized risk of GE pollen flow (Lev-Yadun and Sederoff, 2001), possible use of more than one scion per approved GE rootstock which could help curb the estimated US$136 million (CropLife International, 2011) cost to bring a GE crop to international markets, as well as potential for improved consumer and market acceptance since the consumable product is not itself GE. Thus, transgrafting provides an alternative option for agricultural industries wishing to expand their biotechnology portfolio. Copyright © 2012 Elsevier B.V. All rights reserved.

Prioritizing stream types according to their potential risk to receive crop plant material--A GIS-based procedure to assist in the risk assessment of genetically modified crops and systemic insecticide residues.

Science.gov (United States)

Bundschuh, Rebecca; Kuhn, Ulrike; Bundschuh, Mirco; Naegele, Caroline; Elsaesser, David; Schlechtriemen, Ulrich; Oehen, Bernadette; Hilbeck, Angelika; Otto, Mathias; Schulz, Ralf; Hofmann, Frieder

2016-03-15

Crop plant residues may enter aquatic ecosystems via wind deposition or surface runoff. In the case of genetically modified crops or crops treated with systemic pesticides, these materials may contain insecticidal Bt toxins or pesticides that potentially affect aquatic life. However, the particular exposure pattern of aquatic ecosystems (i.e., via plant material) is not properly reflected in current risk assessment schemes, which primarily focus on waterborne toxicity and not on plant material as the route of uptake. To assist in risk assessment, the present study proposes a prioritization procedure of stream types based on the freshwater network and crop-specific cultivation data using maize in Germany as a model system. To identify stream types with a high probability of receiving crop materials, we developed a formalized, criteria-based and thus transparent procedure that considers the exposure-related parameters, ecological status--an estimate of the diversity and potential vulnerability of local communities towards anthropogenic stress--and availability of uncontaminated reference sections. By applying the procedure to maize, ten stream types out of 38 are expected to be the most relevant if the ecological effects from plant-incorporated pesticides need to be evaluated. This information is an important first step to identifying habitats within these stream types with a high probability of receiving crop plant material at a more local scale, including accumulation areas. Moreover, the prioritization procedure developed in the present study may support the selection of aquatic species for ecotoxicological testing based on their probability of occurrence in stream types having a higher chance of exposure. Finally, this procedure can be adapted to any geographical region or crop of interest and is, therefore, a valuable tool for a site-specific risk assessment of crop plants carrying systemic pesticides or novel proteins, such as insecticidal Bt toxins, expressed

IDENTIFICATION OF ESCAPED TRANSGENIC CREEPING BENTGRASS IN OREGON

Science.gov (United States)

When transgenic plants are cultivated near wild species that are sexually compatible with the crop, gene flow between the crop and wild plants is possible. A resultant concern is that transgene flow and transgene introgression within wild populations could have unintended ecologi...

A Built-In Mechanism to Mitigate the Spread of Insect-Resistance and Herbicide-Tolerance Transgenes into Weedy Rice Populations

Science.gov (United States)

Liu, Chengyi; Li, Jingjing; Gao, Jianhua; Shen, Zhicheng; Lu, Bao-Rong; Lin, Chaoyang

2012-01-01

Background The major challenge of cultivating genetically modified (GM) rice (Oryza sativa) at the commercial scale is to prevent the spread of transgenes from GM cultivated rice to its coexisting weedy rice (O. sativa f. spontanea). The strategic development of GM rice with a built-in control mechanism can mitigate transgene spread in weedy rice populations. Methodology/Principal Findings An RNAi cassette suppressing the expression of the bentazon detoxifying enzyme CYP81A6 was constructed into the T-DNA which contained two tightly linked transgenes expressing the Bt insecticidal protein Cry1Ab and the glyphosate tolerant 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), respectively. GM rice plants developed from this T-DNA were resistant to lepidopteran pests and tolerant to glyphosate, but sensitive to bentazon. The application of bentazon of 2000 mg/L at the rate of 40 mL/m2, which is approximately the recommended dose for the field application to control common rice weeds, killed all F2 plants containing the transgenes generated from the Crop-weed hybrids between a GM rice line (CGH-13) and two weedy rice strains (PI-63 and PI-1401). Conclusions/Significance Weedy rice plants containing transgenes from GM rice through gene flow can be selectively killed by the spray of bentazon when a non-GM rice variety is cultivated alternately in a few-year interval. The built-in control mechanism in combination of cropping management is likely to mitigate the spread of transgenes into weedy rice populations. PMID:22359609

A built-in mechanism to mitigate the spread of insect-resistance and herbicide-tolerance transgenes into weedy rice populations.

Directory of Open Access Journals (Sweden)

Chengyi Liu

Full Text Available BACKGROUND: The major challenge of cultivating genetically modified (GM rice (Oryza sativa at the commercial scale is to prevent the spread of transgenes from GM cultivated rice to its coexisting weedy rice (O. sativa f. spontanea. The strategic development of GM rice with a built-in control mechanism can mitigate transgene spread in weedy rice populations. METHODOLOGY/PRINCIPAL FINDINGS: An RNAi cassette suppressing the expression of the bentazon detoxifying enzyme CYP81A6 was constructed into the T-DNA which contained two tightly linked transgenes expressing the Bt insecticidal protein Cry1Ab and the glyphosate tolerant 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS, respectively. GM rice plants developed from this T-DNA were resistant to lepidopteran pests and tolerant to glyphosate, but sensitive to bentazon. The application of bentazon of 2000 mg/L at the rate of 40 mL/m(2, which is approximately the recommended dose for the field application to control common rice weeds, killed all F(2 plants containing the transgenes generated from the Crop-weed hybrids between a GM rice line (CGH-13 and two weedy rice strains (PI-63 and PI-1401. CONCLUSIONS/SIGNIFICANCE: Weedy rice plants containing transgenes from GM rice through gene flow can be selectively killed by the spray of bentazon when a non-GM rice variety is cultivated alternately in a few-year interval. The built-in control mechanism in combination of cropping management is likely to mitigate the spread of transgenes into weedy rice populations.

Transgenic cotton coexpressing Vip3A and Cry1Ac has a broad insecticidal spectrum against lepidopteran pests.

Science.gov (United States)

Chen, Wen-Bo; Lu, Guo-Qing; Cheng, Hong-Mei; Liu, Chen-Xi; Xiao, Yu-Tao; Xu, Chao; Shen, Zhi-Cheng; Wu, Kong-Ming

2017-10-01

Although farmers in China have grown transgenic Bt-Cry1Ac cotton to resist the major pest Helicoverpa armigera since 1997 with great success, many secondary lepidopteran pests that are tolerant to Cry1Ac are now reported to cause considerable economic damage. Vip3AcAa, a chimeric protein with the N-terminal part of Vip3Ac and the C-terminal part of Vip3Aa, has a broad insecticidal spectrum against lepidopteran pests and has no cross resistance to Cry1Ac. In the present study, we tested insecticidal activities of Vip3AcAa against Spodoptera litura, Spodoptera exigua, and Agrotis ipsilon, which are relatively tolerant to Cry1Ac proteins. The bioassay results showed that insecticidal activities of Vip3AcAa against these three pests are superior to Cry1Ac, and after an activation pretreatment, Vip3AcAa retained insecticidal activity against S. litura, S. exigua and A. ipsilon that was similar to the unprocessed protein. The putative receptor for this chimeric protein in the brush border membrane vesicle (BBMV) in the three pests was also identified using biotinylated Vip3AcAa toxin. To broaden Bt cotton activity against a wider spectrum of pests, we introduced the vip3AcAa and cry1Ac genes into cotton. Larval mortality rates for S. litura, A. ipsilon and S. exigua that had fed on this new cotton increased significantly compared with larvae fed on non-Bt cotton and Bt-Cry1Ac cotton in a laboratory experiment. These results suggested that the Vip3AcAa protein is an excellent option for a "pyramid" strategy for integrated pest management in China. Copyright © 2017 Elsevier Inc. All rights reserved.

Intein-mediated Cre protein assembly for transgene excision in hybrid progeny of transgenic Arabidopsis.

Science.gov (United States)

Ge, Jia; Wang, Lijun; Yang, Chen; Ran, Lingyu; Wen, Mengling; Fu, Xianan; Fan, Di; Luo, Keming

2016-10-01

An approach for restoring recombination activity of complementation split-Cre was developed to excise the transgene in hybrid progeny of GM crops. Growing concerns about the biosafety of genetically modified (GM) crops has currently become a limited factor affecting the public acceptance. Several approaches have been developed to generate selectable-marker-gene-free GM crops. However, no strategy was reported to be broadly applicable to hybrid crops. Previous studies have demonstrated that complementation split-Cre recombinase restored recombination activity in transgenic plants. In this study, we found that split-Cre mediated by split-intein Synechocystis sp. DnaE had high recombination efficiency when Cre recombinase was split at Asp232/Asp233 (866 bp). Furthermore, we constructed two plant expression vectors, pCA-NCre-In and pCA-Ic-CCre, containing NCre866-In and Ic-CCre866 fragments, respectively. After transformation, parent lines of transgenic Arabidopsis with one single copy were generated and used for hybridization. The results of GUS staining demonstrated that the recombination activity of split-Cre could be reassembled in these hybrid progeny of transgenic plants through hybridization and the foreign genes flanked by two loxP sites were efficiently excised. Our strategy may provide an effective approach for generating the next generation of GM hybrid crops without biosafety concerns.

Populations of predators and parasitoids of Bemisia tabaci (Hemiptera: Aleyrodidae) after the application of eight biorational insecticides in vegetable crops.

Science.gov (United States)

Simmons, Alvin M; Shaaban, Abd-Rabou

2011-08-01

The sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), is an important pest of vegetables and many other crops worldwide. Eight biorational insecticides (based on oil, plant derivatives, insect growth regulator and fungus) were evaluated in the field for their influence on populations of six natural enemies of B. tabaci. Natural populations of two predators [Chrysoperla carnea Stephen (Neuroptera: Chrysopidae) and Orius spp. (Hemiptera: Anthocoridae)] and two genera of parasitoids [Encarsia spp. and Eretmocerus spp. (Hymenoptera: Aphelinidae)] were evaluated in eggplant (Solanum melongena L.). Also, augmented field populations of three predators [C. carnea, Coccinella undecimpunctata L. (Coleoptera: Coccinellidae) and Macrolophus caliginosus (Wagner) (Hemiptera: Miridae)] were evaluated in cabbage (Brassica oleracea var. capitata L.), cucumber (Cucumis sativus L.) and squash (Cucurbita pepo L.). Regardless of natural enemy or crop, jojoba oil, Biovar and Neemix had the least effect on abundance of the natural enemies in comparison with the other insecticides during a 14 day evaluation period. Conversely, Admiral, KZ oil, Mesrona oil, Mesrona oil + sulfur and natural oil had a high detrimental effect on abundance of the natural enemies. These results demonstrate the differential effects of biorational insecticides for whitefly control on predators and parasitoids in the field. This article is a US Government work and is in the public domain in the USA. Published 2011 by John Wiley & Sons, Ltd.

The crop-residue of fiber hemp cv. Futura 75: from a waste product to a source of botanical insecticides.

Science.gov (United States)

Benelli, Giovanni; Pavela, Roman; Lupidi, Giulio; Nabissi, Massimo; Petrelli, Riccardo; Ngahang Kamte, Stephane L; Cappellacci, Loredana; Fiorini, Dennis; Sut, Stefania; Dall'Acqua, Stefano; Maggi, Filippo

2018-04-01

In the attempt to exploit the potential of the monoecious fiber hemp cv. Futura 75 in new fields besides textile, cosmetics and food industry, its crop-residue given by leaves and inflorescences was subjected to hydrodistillation to obtain the essential oils. These are niche products representing an ideal candidate for the development of natural insecticides for the control and management of mosquito vectors, houseflies and moth pests. After GC-MS analysis highlighting a safe and legal chemical profile (THC in the range 0.004-0.012% dw), the leaf and inflorescence essential oils were investigated for the insecticidal potential against three insect targets: the larvae of Culex quinquefasciatus and Spodoptera littoralis and the adults of Musca domestica. The essential oil from inflorescences, showing (E)-caryophyllene (21.4%), myrcene (11.3%), cannabidiol (CBD, 11.1%), α-pinene (7.8%), terpinolene (7.6%), and α-humulene (7.1%) as the main components, was more effective than leaf oil against these insects, with LD 50 values of 65.8 μg/larva on S. littoralis, 122.1 μg/adult on M. domestica, and LC 50 of 124.5 μl/l on C. quinquefasciatus larvae. The hemp essential oil moderately inhibited the acetylcholinesterase (AChE), which is a target enzyme in pesticide science. Overall, these results shed light on the future application of fiber hemp crop-residue for the development of effective, eco-friendly and sustainable insecticides.

Glyphostate-drift but not herbivory alters the rate of transgene flow from single and stacked trait transgenic canola (Brassica napus L.) to non-transgenic B. napus and B. rapa

Science.gov (United States)

While transgenic plants can offer agricultural benefits, the escape of transgenes out of crop fields is a major environmental concern. Escape of transgenic herbicide resistance has occurred between transgenic Brassica napus (canola) and weedy species in numerous locations. In t...

In silico assessment of the potential allergenicity of transgenes used for the development of GM food crops.

Science.gov (United States)

Mishra, Ankita; Gaur, S N; Singh, B P; Arora, Naveen

2012-05-01

Genetically modified (GM) crops require allergenicity and toxicity assessment of the novel protein(s) to ensure complete safety to the consumers. These assessments are performed in accordance with the guidelines proposed by Codex (2003) and ICMR (2008). The guidelines recommend sequence homology analysis as a preliminary step towards allergenicity prediction, later in vitro experiments may be performed to confirm allergenicity. In the present study, an in silico approach is employed to evaluate the allergenic potential of six transgenes routinely used for the development of GM food crops. Among the genes studied, manganese superoxide dismutase (MnSOD) and osmotin shares greater than 90% identity with Hev b 10 and Cap a 1w, respectively. Chitinase shares greater than 70% identity with allergens namely Pers a 1 and Hev b 11, and fungal chitinase showed significant IgE binding with 7 of 75 patients' sera positive to different food extracts. Glucanases (alfalfa, wheat) and glycine betaine aldehyde dehydrogenase gene share 50% homology with allergens like - Ole e 9, Cla h 10 and Alt a 10. The results demonstrate the allergenic potential of six genes and can serve as a guide for selection of transgenes to develop GM crops. Copyright © 2012 Elsevier Ltd. All rights reserved.

Insecticides and Biological Control

Science.gov (United States)

Furness, G. O.

1972-01-01

Use of insecticides has been questioned due to their harmful effects on edible items. Biological control of insects along with other effective practices for checking spread of parasites on crops are discussed. (PS)

Response to issues on GM agriculture in Africa: Are transgenic crops safe?

Directory of Open Access Journals (Sweden)

Adenle Ademola A

2011-10-01

Full Text Available Abstract The controversies surrounding transgenic crops, often called Genetically Modified Organisms (GMOs, call for a need to raise the level of public awareness of Genetic Modification (GM technology in Africa. This should be accomplished by educating the public about the potential benefits and risks that may be associated with this new technology. In the last 15 years, GM crop producing countries have benefited from adoption of this new technology in the form of improved crop productivity, food security, and quality of life. The increased income to resource-poor farmers is a key benefit at the individual level especially as most countries using this technology are in the developing world, including three African countries (South Africa, Burkina Faso and Egypt. Despite clear benefits to countries and farmers who grow GMOs, many people are concerned about suspected potential risks associated with GMOs. This sparks debate as to whether GM technology should be adopted or not. Given the concerns regarding the safety of GMO products, thorough scientific investigation of safe application of GMOs is required. The objective of this paper is to respond to the issues of GM agriculture in Africa and some of the issues surrounding the adoption of GM crops between developed and developing countries. In this article, I analyse relevant papers relating to the adoption of GM technology particularly in developing countries including the few African countries that have adopted GM crops. The issues discussed span a wide range including: safety; potential benefits and risks; disputes between the United States of America (USA and the European Union (EU over adoption of GM crops with a focus on Africa continent. This article is concluded by summarising the issues raised and how GM technology can be adopted for agricultural development in Africa.

Response to issues on GM agriculture in Africa: Are transgenic crops safe?

Science.gov (United States)

Adenle, Ademola A

2011-10-08

The controversies surrounding transgenic crops, often called Genetically Modified Organisms (GMOs), call for a need to raise the level of public awareness of Genetic Modification (GM) technology in Africa. This should be accomplished by educating the public about the potential benefits and risks that may be associated with this new technology. In the last 15 years, GM crop producing countries have benefited from adoption of this new technology in the form of improved crop productivity, food security, and quality of life. The increased income to resource-poor farmers is a key benefit at the individual level especially as most countries using this technology are in the developing world, including three African countries (South Africa, Burkina Faso and Egypt). Despite clear benefits to countries and farmers who grow GMOs, many people are concerned about suspected potential risks associated with GMOs. This sparks debate as to whether GM technology should be adopted or not. Given the concerns regarding the safety of GMO products, thorough scientific investigation of safe application of GMOs is required. The objective of this paper is to respond to the issues of GM agriculture in Africa and some of the issues surrounding the adoption of GM crops between developed and developing countries. In this article, I analyse relevant papers relating to the adoption of GM technology particularly in developing countries including the few African countries that have adopted GM crops. The issues discussed span a wide range including: safety; potential benefits and risks; disputes between the United States of America (USA) and the European Union (EU) over adoption of GM crops with a focus on Africa continent. This article is concluded by summarising the issues raised and how GM technology can be adopted for agricultural development in Africa.

Cry1Ac Protein expression in tissues of potato (solanumtuberosum spp. andigena) transgenic lines var. Diacol Capiro

International Nuclear Information System (INIS)

Vanegas Araujo, Pablo Andres; Blanco Martinez, Jennifer Teresa; Chaparro Giraldo, Alejandro

2010-01-01

The potato plant is the fourth most important crop in the world. In Colombia around 2.8 million tons are produced annually economically supporting 90000 families. In the country, the major economic impact in the crop is caused by Tecia solanivora that originates loses up to 100% in the tuber production. The genetic plant breeding related to the introduction of Cry genes which codify insecticidal crystal proteins is an alternative for reducing the insect attack in commercial crops. In this work, the insertion, transcription and expression of Cry1Ac gen was characterized in different tissues and three development stages of two transgenic lines of Solanum tuberosum variety Diacol Capiro that were previously transformed by Agrobacterium tumefaciens method. The characterization was realized by PCR, RT-PCR and ELISA techniques. The gen insertion and transcription was confirmed using primers for Cry1Ac gen that amplified a specific band of 766 bp. The protein expression levels were higher than 45 µg/g and were not significantly different between the analyzed lines or the three development stages. Furthermore, taking into account some relevant phenotypic features, no significant differences were found between transgenic lines and controls. The results suggest that monitoring and biosecurity assays are necessary with this vegetal material because their high level expression inside all the tissues analyzed that could affect non-targeted insects.

Expression and Chloroplast Targeting of Cholesterol Oxidase in Transgenic Tobacco Plants

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Corbin, David R.; Grebenok, Robert J.; Ohnmeiss, Thomas E.; Greenplate, John T.; Purcell, John P.

2001-01-01

Cholesterol oxidase represents a novel type of insecticidal protein with potent activity against the cotton boll weevil (Anthonomus grandis grandis Boheman). We transformed tobacco (Nicotiana tabacum) plants with the cholesterol oxidase choM gene and expressed cytosolic and chloroplast-targeted versions of the ChoM protein. Transgenic leaf tissues expressing cholesterol oxidase exerted insecticidal activity against boll weevil larvae. Our results indicate that cholesterol oxidase can metabolize phytosterols in vivo when produced cytosolically or when targeted to chloroplasts. The transgenic plants exhibiting cytosolic expression accumulated low levels of saturated sterols known as stanols, and displayed severe developmental aberrations. In contrast, the transgenic plants expressing chloroplast-targeted cholesterol oxidase maintained a greater accumulation of stanols, and appeared phenotypically and developmentally normal. These results are discussed within the context of plant sterol distribution and metabolism. PMID:11457962

Gone with transgenic cotton cropping in the USA. A perception of the presentations and interactions at the Beltwide Cotton Conferences, New Orleans (Louisiana, USA, 4-7/01/2010

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Fok, M.

2011-01-01

Full Text Available The 2010 Beltwide Cotton Conferences provided a new vision of the consequences of about 15 years of widespread and uncoordinated cropping of transgenic cotton in the United States. Insect-resistant and/or herbicide-tolerant cotton varieties modified parasite complexes, namely those of insects and weeds damaging cotton crops. The Conferences have revealed that the adaptation solutions so far proposed make illusory the expectations at the launch of transgenic cotton, in terms of effective pest control, cost reduction, and antagonism between chemical and biotech methods. The USA case points out that the technical and economic sustainability of transgenic varieties must lie in a systemic and coordinated approach.

Appropriate analytical methods are necessary to assess nontarget effects of insecticidal proteins in GM crops through meta-analysis (Response to Andow et al. 2009)

Czech Academy of Sciences Publication Activity Database

Shelton, A. M.; Naranjo, S. E.; Romeis, J.; Hellmich, R. L.; Wolt, J. D.; Federici, B. A.; Albajes, R.; Bigler, F.; Burgess, E. P. J.; Dively, G. P.; Gatehouse, A. M. R.; Malone, L. A.; Roush, R.; Sears, M.; Sehnal, František; Ferry, N.; Bell, H. A.

2009-01-01

Roč. 38, č. 6 (2009), s. 1533-1538 ISSN 0046-225X Institutional research plan: CEZ:AV0Z50070508 Keywords : GM crops * insecticidal proteins * analytical methods Subject RIV: GF - Plant Pathology, Vermin, Weed, Plant Protection Impact factor: 1.154, year: 2009

Evidence of multiple/cross resistance to Bt and organophosphate insecticides in Puerto Rico population of the fall armyworm, Spodoptera frugiperda.

Science.gov (United States)

Zhu, Yu Cheng; Blanco, Carlos A; Portilla, Maribel; Adamczyk, John; Luttrell, Randall; Huang, Fangneng

2015-07-01

Fall armyworm (FAW) is a damaging pest of many economic crops. Long-term use of chemical control prompted resistance development to many insecticide classes. Many populations were found to be significantly less susceptible to major Bt toxins expressed in transgenic crops. In this study, a FAW strain collected from Puerto Rico (PR) with 7717-fold Cry1F-resistance was examined to determine if it had also developed multiple/cross resistance to non-Bt insecticides. Dose response assays showed that the PR strain developed 19-fold resistance to acephate. Besides having a slightly smaller larval body weight and length, PR also evolved a deep (2.8%) molecular divergence in mitochondrial oxidase subunit II. Further examination of enzyme activities in the midgut of PR larvae exhibited substantial decreases of alkaline phosphatase (ALP), aminopeptidase (APN), 1-NA- and 2-NA-specific esterase, trypsin, and chymotrypsin activities, and significant increases of PNPA-specific esterase and glutathione S-transferase (GST) activities. When enzyme preparations from the whole larval body were examined, all three esterase, GST, trypsin, and chymotrypsin activities were significantly elevated in the PR strain, while ALP and APN activities were not significantly different from those of susceptible strain. Data indicated that multiple/cross resistances may have developed in the PR strain to both Bt toxins and conventional insecticides. Consistently reduced ALP provided evidence to support an ALP-mediated Bt resistance mechanism. Esterases and GSTs may be associated with acephate resistance through elevated metabolic detoxification. Further studies are needed to clarify whether and how esterases, GSTs, and other enzymes (such as P450s) are involved in cross resistance development to Bt and other insecticide classes. Published by Elsevier Inc.

Genetically modified (GM) crops: milestones and new advances in crop improvement.

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Kamthan, Ayushi; Chaudhuri, Abira; Kamthan, Mohan; Datta, Asis

2016-09-01

New advances in crop genetic engineering can significantly pace up the development of genetically improved varieties with enhanced yield, nutrition and tolerance to biotic and abiotic stresses. Genetically modified (GM) crops can act as powerful complement to the crops produced by laborious and time consuming conventional breeding methods to meet the worldwide demand for quality foods. GM crops can help fight malnutrition due to enhanced yield, nutritional quality and increased resistance to various biotic and abiotic stresses. However, several biosafety issues and public concerns are associated with cultivation of GM crops developed by transgenesis, i.e., introduction of genes from distantly related organism. To meet these concerns, researchers have developed alternative concepts of cisgenesis and intragenesis which involve transformation of plants with genetic material derived from the species itself or from closely related species capable of sexual hybridization, respectively. Recombinase technology aimed at site-specific integration of transgene can help to overcome limitations of traditional genetic engineering methods based on random integration of multiple copy of transgene into plant genome leading to gene silencing and unpredictable expression pattern. Besides, recently developed technology of genome editing using engineered nucleases, permit the modification or mutation of genes of interest without involving foreign DNA, and as a result, plants developed with this technology might be considered as non-transgenic genetically altered plants. This would open the doors for the development and commercialization of transgenic plants with superior phenotypes even in countries where GM crops are poorly accepted. This review is an attempt to summarize various past achievements of GM technology in crop improvement, recent progress and new advances in the field to develop improved varieties aimed for better consumer acceptance.

Incipient resistance of Helicoverpa punctigera to the Cry2Ab Bt toxin in Bollgard II cotton.

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Sharon Downes

Full Text Available Combinations of dissimilar insecticidal proteins ("pyramids" within transgenic plants are predicted to delay the evolution of pest resistance for significantly longer than crops expressing a single transgene. Field-evolved resistance to Bacillus thuringiensis (Bt transgenic crops has been reported for first generation, single-toxin varieties and the Cry1 class of proteins. Our five year data set shows a significant exponential increase in the frequency of alleles conferring Cry2Ab resistance in Australian field populations of Helicoverpa punctigera since the adoption of a second generation, two-toxin Bt cotton expressing this insecticidal protein. Furthermore, the frequency of cry2Ab resistance alleles in populations from cropping areas is 8-fold higher than that found for populations from non-cropping regions. This report of field evolved resistance to a protein in a dual-toxin Bt-crop has precisely fulfilled the intended function of monitoring for resistance; namely, to provide an early warning of increases in frequencies that may lead to potential failures of the transgenic technology. Furthermore, it demonstrates that pyramids are not 'bullet proof' and that rapid evolution to Bt toxins in the Cry2 class is possible.

Tissue specific expression of potent insecticidal, Allium sativum leaf agglutinin (ASAL) in important pulse crop, chickpea (Cicer arietinum L.) to resist the phloem feeding Aphis craccivora.

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Chakraborti, Dipankar; Sarkar, Anindya; Mondal, Hossain Ali; Das, Sampa

2009-08-01

The phloem sap-sucking hemipteran insect, Aphis craccivora, commonly known as cowpea aphid, cause major yield loss of important food legume crop chickpea. Among different plant lectins Allium sativum leaf agglutinin (ASAL), a mannose binding lectin was found to be potent antifeedant for sap sucking insect A. craccivora. Present study describes expression of ASAL in chickpea through Agrobacterium-mediated transformation of "single cotyledon with half embryo" explant. ASAL was expressed under the control of CaMV35S promoter for constitutive expression and phloem specific rolC promoter for specifically targeting the toxin at feeding site, using pCAMBIA2301 vector containing plant selection marker nptII. Southern blot analysis demonstrated the integration and copy number of chimeric ASAL gene in chickpea and its inheritance in T(1) and T(2) progeny plants. Expression of ASAL in T(0) and T(1) plants was confirmed through northern and western blot analysis. The segregation pattern of ASAL transgene was observed in T(1) progenies, which followed the 3:1 Mendelian ratio. Enzyme linked immunosorbant assay (ELISA) determined the level of ASAL expression in different transgenic lines in the range of 0.08-0.38% of total soluble protein. The phloem tissue specific expression of ASAL gene driven by rolC promoter has been monitored by immunolocalization analysis of mature stem sections. Survival and fecundity of A. craccivora decreased to 11-26% and 22-42%, respectively when in planta bioassay conducted on T(1) plants compared to untransformed control plant which showed 85% survival. Thus, through unique approach of phloem specific expression of novel insecticidal lectin (ASAL), aphid resistance has been successfully achieved in chickpea.

Sampling Strategies for Evaluating the Rate of Adventitious Transgene Presence in Non-Genetically Modified Crop Fields.

Science.gov (United States)

Makowski, David; Bancal, Rémi; Bensadoun, Arnaud; Monod, Hervé; Messéan, Antoine

2017-09-01

According to E.U. regulations, the maximum allowable rate of adventitious transgene presence in non-genetically modified (GM) crops is 0.9%. We compared four sampling methods for the detection of transgenic material in agricultural non-GM maize fields: random sampling, stratified sampling, random sampling + ratio reweighting, random sampling + regression reweighting. Random sampling involves simply sampling maize grains from different locations selected at random from the field concerned. The stratified and reweighting sampling methods make use of an auxiliary variable corresponding to the output of a gene-flow model (a zero-inflated Poisson model) simulating cross-pollination as a function of wind speed, wind direction, and distance to the closest GM maize field. With the stratified sampling method, an auxiliary variable is used to define several strata with contrasting transgene presence rates, and grains are then sampled at random from each stratum. With the two methods involving reweighting, grains are first sampled at random from various locations within the field, and the observations are then reweighted according to the auxiliary variable. Data collected from three maize fields were used to compare the four sampling methods, and the results were used to determine the extent to which transgene presence rate estimation was improved by the use of stratified and reweighting sampling methods. We found that transgene rate estimates were more accurate and that substantially smaller samples could be used with sampling strategies based on an auxiliary variable derived from a gene-flow model. © 2017 Society for Risk Analysis.

Transgene flow: Facts, speculations and possible countermeasures

Science.gov (United States)

Ryffel, Gerhart U

2014-01-01

Convincing evidence has accumulated that unintended transgene escape occurs in oilseed rape, maize, cotton and creeping bentgrass. The escaped transgenes are found in variant cultivars, in wild type plants as well as in hybrids of sexually compatible species. The fact that in some cases stacked events are present that have not been planted commercially, implies unintended recombination of transgenic traits. As the consequences of this continuous transgene escape for the ecosystem cannot be reliably predicted, I propose to use more sophisticated approaches of gene technology in future. If possible GM plants should be constructed using either site-directed mutagenesis or cisgenic strategies to avoid the problem of transgene escape. In cases where a transgenic trait is needed, efficient containment should be the standard approach. Various strategies available or in development are discussed. Such a cautious approach in developing novel types of GM crops will enhance the sustainable potential of GM crops and thus increase the public trust in green gene technology. PMID:25523171

Detection and characterization of recombinant DNA expressing vip3A-type insecticidal gene in GMOs--standard single, multiplex and construct-specific PCR assays.

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Singh, Chandra K; Ojha, Abhishek; Bhatanagar, Raj K; Kachru, Devendra N

2008-01-01

Vegetative insecticidal protein (Vip), a unique class of insecticidal protein, is now part of transgenic plants for conferring resistance against lepidopteron pests. In order to address the imminent regulatory need for detection and labeling of vip3A carrying genetically modified (GM) products, we have developed a standard single PCR and a multiplex PCR assay. As far as we are aware, this is the first report on PCR-based detection of a vip3A-type gene (vip-s) in transgenic cotton and tobacco. Our assay involves amplification of a 284-bp region of the vip-s gene. This assay can possibly detect as many as 20 natural wild-type isolates bearing a vip3A-like gene and two synthetic genes of vip3A in transgenic plants. The limit of detection as established by our assay for GM trait (vip-s) is 0.1%. Spiking with nontarget DNA originating from diverse plant sources had no inhibitory effect on vip-s detection. Since autoclaving of vip-s bearing GM leaf samples showed no deterioration/interference in detection efficacy, the assay seems to be suitable for processed food products as well. The vip-s amplicon identity was reconfirmed by restriction endonuclease assay. The primer set for vip-s was equally effective in a multiplex PCR assay format (duplex, triplex and quadruplex), used in conjunction with the primer sets for the npt-II selectable marker gene, Cauliflower mosaic virus 35S promoter and nopaline synthetase terminator, enabling concurrent detection of the transgene, regulatory sequences and marker gene. Further, the entire transgene construct was amplified using the forward primer of the promoter and the reverse primer of the terminator. The resultant amplicon served as a template for nested PCR to confirm the construct integrity. The method is suitable for screening any vip3A-carrying GM plant and food. The availability of a reliable PCR assay method prior to commercial release of vip3A-based transgenic crops and food would facilitate rapid and efficient regulatory

Genomic misconception: a fresh look at the biosafety of transgenic and conventional crops. A plea for a process agnostic regulation.

Science.gov (United States)

Ammann, Klaus

2014-01-25

The regulation of genetically engineered crops, in Europe and within the legislation of the Cartagena biosafety protocol is built on false premises: The claim was (and unfortunately still is) that there is a basic difference between conventional and transgenic crops, this despite the fact that this has been rejected on scientifically solid grounds since many years. This contribution collects some major arguments for a fresh look at regulation of transgenic crops, they are in their molecular processes of creation not basically different from conventional crops, which are based in their breeding methods on natural, sometimes enhanced mutation. But the fascination and euphoria of the discoveries in molecular biology and the new perspectives in plant breeding in the sixties and seventies led to the wrong focus on transgenic plants alone. In a collective framing process the initial biosafety debates focused on the novelty of the process of transgenesis. When early debates on the risk assessment merged into legislative decisions, this wrong focus on transgenesis alone seemed uncontested. The process-focused view was also fostered by a conglomerate of concerned scientists and biotechnology companies, both with a vested interest to at least tolerate the rise of the safety threshold to secure research money and to discourage competitors of all kinds. Policy minded people and opponent activists without deeper insight in the molecular science agreed to those efforts without much resistance. It is interesting to realize, that the focus on processes was uncontested by a majority of regulators, this despite of serious early warnings from important authorities in science, mainly of US origin. It is time to change the regulation of genetically modified (GM) crops toward a more science based process-agnostic legislation. Although this article concentrates on the critique of the process-oriented regulation, including some details about the history behind, there should be no

Biofortified Crops Generated by Breeding, Agronomy, and Transgenic Approaches Are Improving Lives of Millions of People around the World

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Monika Garg

2018-02-01

Full Text Available Biofortification is an upcoming, promising, cost-effective, and sustainable technique of delivering micronutrients to a population that has limited access to diverse diets and other micronutrient interventions. Unfortunately, major food crops are poor sources of micronutrients required for normal human growth. The manuscript deals in all aspects of crop biofortification which includes—breeding, agronomy, and genetic modification. It tries to summarize all the biofortification research that has been conducted on different crops. Success stories of biofortification include lysine and tryptophan rich quality protein maize (World food prize 2000, Vitamin A rich orange sweet potato (World food prize 2016; generated by crop breeding, oleic acid, and stearidonic acid soybean enrichment; through genetic transformation and selenium, iodine, and zinc supplementation. The biofortified food crops, especially cereals, legumes, vegetables, and fruits, are providing sufficient levels of micronutrients to targeted populations. Although a greater emphasis is being laid on transgenic research, the success rate and acceptability of breeding is much higher. Besides the challenges biofortified crops hold a bright future to address the malnutrition challenge.

Biofortified Crops Generated by Breeding, Agronomy, and Transgenic Approaches Are Improving Lives of Millions of People around the World.

Science.gov (United States)

Garg, Monika; Sharma, Natasha; Sharma, Saloni; Kapoor, Payal; Kumar, Aman; Chunduri, Venkatesh; Arora, Priya

2018-01-01

Biofortification is an upcoming, promising, cost-effective, and sustainable technique of delivering micronutrients to a population that has limited access to diverse diets and other micronutrient interventions. Unfortunately, major food crops are poor sources of micronutrients required for normal human growth. The manuscript deals in all aspects of crop biofortification which includes-breeding, agronomy, and genetic modification. It tries to summarize all the biofortification research that has been conducted on different crops. Success stories of biofortification include lysine and tryptophan rich quality protein maize (World food prize 2000), Vitamin A rich orange sweet potato (World food prize 2016); generated by crop breeding, oleic acid, and stearidonic acid soybean enrichment; through genetic transformation and selenium, iodine, and zinc supplementation. The biofortified food crops, especially cereals, legumes, vegetables, and fruits, are providing sufficient levels of micronutrients to targeted populations. Although a greater emphasis is being laid on transgenic research, the success rate and acceptability of breeding is much higher. Besides the challenges biofortified crops hold a bright future to address the malnutrition challenge.

Carboxylesterase-mediated insecticide resistance: Quantitative increase induces broader metabolic resistance than qualitative change.

Science.gov (United States)

Cui, Feng; Li, Mei-Xia; Chang, Hai-Jing; Mao, Yun; Zhang, Han-Ying; Lu, Li-Xia; Yan, Shuai-Guo; Lang, Ming-Lin; Liu, Li; Qiao, Chuan-Ling

2015-06-01

Carboxylesterases are mainly involved in the mediation of metabolic resistance of many insects to organophosphate (OP) insecticides. Carboxylesterases underwent two divergent evolutionary events: (1) quantitative mechanism characterized by the overproduction of carboxylesterase protein; and (2) qualitative mechanism caused by changes in enzymatic properties because of mutation from glycine/alanine to aspartate at the 151 site (G/A151D) or from tryptophan to leucine at the 271 site (W271L), following the numbering of Drosophila melanogaster AChE. Qualitative mechanism has been observed in few species. However, whether this carboxylesterase mutation mechanism is prevalent in insects remains unclear. In this study, wild-type, G/A151D and W271L mutant carboxylesterases from Culex pipiens and Aphis gossypii were subjected to germline transformation and then transferred to D. melanogaster. These germlines were ubiquitously expressed as induced by tub-Gal4. In carboxylesterase activity assay, the introduced mutant carboxylesterase did not enhance the overall carboxylesterase activity of flies. This result indicated that G/A151D or W271L mutation disrupted the original activities of the enzyme. Less than 1.5-fold OP resistance was only observed in flies expressing A. gossypii mutant carboxylesterases compared with those expressing A. gossypii wild-type carboxylesterase. However, transgenic flies universally showed low resistance to OP insecticides compared with non-transgenic flies. The flies expressing A. gossypii W271L mutant esterase exhibited 1.5-fold resistance to deltamethrin, a pyrethroid insecticide compared with non-transgenic flies. The present transgenic Drosophila system potentially showed that a quantitative increase in carboxylesterases induced broader resistance of insects to insecticides than a qualitative change. Copyright © 2014 Elsevier Inc. All rights reserved.

A Landscape View of Agricultural Insecticide Use across the Conterminous US from 1997 through 2012.

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Timothy D Meehan

Full Text Available Simplification of agricultural landscapes is expected to have positive effects on many crop pests and negative effects on their natural enemies, potentially leading to increased pest pressure, decreased crop yield, and increased insecticide use. While many intermediate links in this causal chain have empirical support, there is mixed evidence for ultimate relationships between landscape simplification, crop yield, and insecticide use, especially at large spatial and temporal scales. We explored relationships between landscape simplification (proportion of a county in harvested cropland and insecticide use (proportion of harvested cropland treated with insecticides, using county-level data from the US Census of Agriculture and a variety of standard and spatiotemporal regression techniques. The best model indicated that insecticide use across the US has increased between 1997 and 2012, was strongly dependent on the crops grown in a county, increased with average farm income and size, and increased with annual growing degree days. After accounting for those variables, and other unidentified spatial and temporal structure in the data, there remained a statistically significant, moderate, positive relationship between insecticide use and landscape simplification. These results lend general support to the causal chain outlined above, and to the notion that a landscape perspective is useful for managing ecosystem services that are provided by mobile organisms and valuable to agriculture.

Reproductive fitness of outcrossed hybrids between transgenic broccoli (brassica oleracea) carrying the ipt transgene and conventional varieties of kale, broccoli and cauliflower

International Nuclear Information System (INIS)

Ting, P.; Tu, Y.; Lin, C.; Chang, H.; Chen, L.; Litfu, A

2014-01-01

Pollens are potential carriers for genetically modified crops to transfer genetic materials horizontally to other plants. For phanerogams, pollen viability and cross-compatibility are critical factors for successful outcross hybridization. To evaluate this possibility, this project investigated pollen viability and pod setting rate by comparing broccoli (Brassica oleracea L. var. italica Planck) and broccoli transformed with the isopentenyl transferase (ipt) gene. Both served as pollen donors and four other varieties as pollen receptors to determine outcross rates. For pollen viability, F1 progeny was higher (p?0.05) for the cross of transgenic ipt broccoli with Li Syue significantly by FDA (fluorescein diacetate) assay. Higher successful hybrids were observed for transgenic ipt broccoli with Fu Yue, Li Syue and Green King. As pollen properties, number and grain diameter were significantly larger (p?0.05) in hybrid combinations of transgenic ipt broccoli with Li Syue and Green King significantly (p?0.05). The pod setting rates were higher while transgenic ipt broccoli served as donor plant. These results analyzing pollen properties between transgenic crops with possible outcross candidates would serve as one of those critical strategies for evaluating environmental biosafety issues for transgenic crops. (author)

Screening of transgenic proteins expressed in transgenic food crops for the presence of short amino acid sequences identical to potential, IgE – binding linear epitopes of allergens

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Peijnenburg Ad ACM

2002-12-01

Full Text Available Abstract Background Transgenic proteins expressed by genetically modified food crops are evaluated for their potential allergenic properties prior to marketing, among others by identification of short identical amino acid sequences that occur both in the transgenic protein and allergenic proteins. A strategy is proposed, in which the positive outcomes of the sequence comparison with a minimal length of six amino acids are further screened for the presence of potential linear IgE-epitopes. This double track approach involves the use of literature data on IgE-epitopes and an antigenicity prediction algorithm. Results Thirty-three transgenic proteins have been screened for identities of at least six contiguous amino acids shared with allergenic proteins. Twenty-two transgenic proteins showed positive results of six- or seven-contiguous amino acids length. Only a limited number of identical stretches shared by transgenic proteins (papaya ringspot virus coat protein, acetolactate synthase GH50, and glyphosate oxidoreductase and allergenic proteins could be identified as (part of potential linear epitopes. Conclusion Many transgenic proteins have identical stretches of six or seven amino acids in common with allergenic proteins. Most identical stretches are likely to be false positives. As shown in this study, identical stretches can be further screened for relevance by comparison with linear IgE-binding epitopes described in literature. In the absence of literature data on epitopes, antigenicity prediction by computer aids to select potential antibody binding sites that will need verification of IgE binding by sera binding tests. Finally, the positive outcomes of this approach warrant further clinical testing for potential allergenicity.

Climate change, transgenic corn adoption and field-evolved resistance in corn earworm.

Science.gov (United States)

Venugopal, P Dilip; Dively, Galen P

2017-06-01

Increased temperature anomaly during the twenty-first century coincides with the proliferation of transgenic crops containing the bacterium Bacillus thuringiensis (Berliner) (Bt) to express insecticidal Cry proteins. Increasing temperatures profoundly affect insect life histories and agricultural pest management. However, the implications of climate change on Bt crop-pest interactions and insect resistance to Bt crops remains unexamined. We analysed the relationship of temperature anomaly and Bt adoption with field-evolved resistance to Cry1Ab Bt sweet corn in a major pest, Helicoverpa zea (Boddie). Increased Bt adoption during 1996-2016 suppressed H. zea populations, but increased temperature anomaly buffers population reduction. Temperature anomaly and its interaction with elevated selection pressure from high Bt acreage probably accelerated the Bt-resistance development. Helicoverpa zea damage to corn ears, kernel area consumed, mean instars and proportion of late instars in Bt varieties increased with Bt adoption and temperature anomaly, through additive or interactive effects. Risk of Bt-resistant H. zea spreading is high given extensive Bt adoption, and the expected increase in overwintering and migration. Our study highlights the challenges posed by climate change for Bt biotechnology-based agricultural pest management, and the need to incorporate evolutionary processes affected by climate change into Bt-resistance management programmes.

Concentration-mortality responses of Myzus persicae and natural enemies to selected insecticides.

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Bacci, Leandro; Rosado, Jander F; Picanço, Marcelo C; Pereira, Eliseu J G; Silva, Gerson A; Martins, Júlio C

2012-01-01

The toxicity of six insecticides was determined for the peach-potato aphid, Myzus persicae (Hemiptera: Aphididae), and some of its natural enemies - the predatory beetles Cycloneda sanguinea (Coccinellidae) and Acanthinus sp. (Anthicidae), and the wasp parasitoid Diaeretiella rapae (Aphidiidae). Natural enemies from these groups are important natural biological control agents in a number of agroecosystems, and insecticides potentially safe to these non-target organisms should be identified using standardized tests. Thus, concentration-mortality bioassays were carried out with both the aphid and its natural enemies to assess the toxicity and selectivity of acephate, deltamethrin, dimethoate, methamidophos, methyl parathion, and pirimicarb. The latter insecticide was highly selective to all natural enemies tested, and its LC(90) for M. persicae was 14-fold lower than the field rate recommended for control of the aphid in brassica crops. Methyl parathion also showed selectivity to C. sanguinea and Acanthinus sp., but not to D. rapae. Acephate was the least potent insecticide against M. persicae and was equally or more toxic to the natural enemies relative to the aphid. Pirimicarb and methyl parathion were efficient against M. persicae and selective in favor of two of the natural enemies tested. Acanthinus sp. and C. sanguinea were more tolerant to the insecticides than was the parasitoid D. rapae. This study shows that there are selective insecticides that may be compatible with conservation of natural enemies in brassica crops, which is important practical information to improve integrated pest management systems in these crops.

Effects of insecticide spray application on insect pest infestation and ...

African Journals Online (AJOL)

Field studies were conducted during the 2008 - 2009 cropping season to determine the minimal insecticide application which can reduce cowpea yield losses on the field due to insect pest infestations in the Transkei region of South Africa. Treatments consisted of five cowpea varieties and four regimes of insecticide spray ...

Grand challenges for crop science

Science.gov (United States)

Crop science is a highly integrative science using the disciplines of conventional plant breeding, transgenic crop improvement, plant physiology, and cropping system sciences to develop improved varieties of agronomic, turf, and forage crops to produce feed, food, fuel, and fiber for our world's gro...

Emamectin benzoate (Affirm). a modern insecticide for the control of lepidoptera larvae on fruits, grapes and vegetables crops.

Science.gov (United States)

Liguori, R; Correia, R; Thomas, C; Decaudin, B; Cisneros, J; Lopez, A

2010-01-01

Emamectin benzoate (Affirm) is a novel insecticide with potent efficacy against many specie of lepidoptera which are damaging fruits and leaves of agricultural crops. The active ingredient belongs to the naturally derived chemical group of avermectine, causing paralysis of lepidoptera larvae due to the activation of chloride channel at nerves level. Affirm is acting mainly through ingestion, due to its mode of action and fast activity, it is effective at very low rates and on all instars stages. It has been developed for the use on pomefruits, stonefruits, grapes and a broda range of vegetables crops at a rate range of 1.5 to 3 g ai/100L. The product shows translaminar activity and rapid degradation on leaf surface; therefore the active ingredient breaks down in a very short time to sublethal doses for most beneficials organisms living on the vegetation. The short rentry time, generally 24 hours for beneficials and impollinators, makes Affirm compatible for IPM programme in orchards and greenhouses. Also the residue profile is very favourable, leading to a very low maximum residue level and short preharvest interval in all edible crops.

Hybridization between crops and wild relatives: the contribution of cultivated lettuce to the vigour of crop-wild hybrids under drought, salinity and nutrient deficiency conditions

NARCIS (Netherlands)

Uwimana, B.; Smulders, M.J.M.; Hooftman, D.A.P.; Hartman, Y.; van Tienderen, P.H.; Jansen, J.; McHale, L.K.; Michelmore, R.W.; van de Wiel, C.C.M.; Visser, R.G.F.

2012-01-01

With the development of transgenic crop varieties, crop-wild hybridization has received considerable consideration with regard to the potential of transgenes to be transferred to wild species. Although many studies have shown that crops can hybridize with their wild relatives and that the resulting

Rice Production without Insecticide in Smallholder Farmer's Field

Directory of Open Access Journals (Sweden)

M. P. Ali

2017-05-01

Full Text Available Highlights:Use of perching, sweeping, and need based insecticide (IPM technique useage produce at par yields compared to prophylactic insecticide useage in rice fields.There exists a technique that can reduce 75% of insecticide useage in rice field.The results were obtained in cooperation between smallholder rice farmers and researchers of Bangladesh.Currently rice protection from insect pests solely depends on chemical pesticides which have tremendous impact on biodiversity, environment, animal, and human health. To reduce their impact from our society we need to cut pesticide use from agricultural practices. To address this issue, we did an experiment to identify realistic solutions that could help farmers build sustainable crop protection systems and minimize useage of insecticides and thus reduce the impact of pesticides in the environment. Innovations developed jointly by farmers and researchers and evaluated for their potential to be adopted by more farmers. In this paper we tested four management practices jointly with smallholder farmer fields in order to select the best one. Four management practices were used namely, T1 = Prophylactic use of insecticide where insecticide was applied in rice field at every 15 days interval without judging the infestation level; T2 = Perching (that is, placing roosting (perching sites for insectivorous birds within the rice field and concurrent sweep net samples along with need-based insecticide application; T3 = Perching only; and T4 = Farmer's own practices. The results revealed that routine application of insecticides for crop protection is not mandatory which is commonly found at use in rice farmers. In our experiment, where prophylactic method or farmers used 3–4 times insecticides without judging the insect pests infestation level, the similar pest population was found when compared to the field where insecticide was not applied. Our management system reduced by 75% the use of insecticides even

Pollen- and seed-mediated transgene flow in commercial cotton seed production fields.

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Shannon Heuberger

Full Text Available BACKGROUND: Characterizing the spatial patterns of gene flow from transgenic crops is challenging, making it difficult to design containment strategies for markets that regulate the adventitious presence of transgenes. Insecticidal Bacillus thuringiensis (Bt cotton is planted on millions of hectares annually and is a potential source of transgene flow. METHODOLOGY/PRINCIPAL FINDINGS: Here we monitored 15 non-Bt cotton (Gossypium hirsutum, L. seed production fields (some transgenic for herbicide resistance, some not for gene flow of the Bt cotton cry1Ac transgene. We investigated seed-mediated gene flow, which yields adventitious Bt cotton plants, and pollen-mediated gene flow, which generates outcrossed seeds. A spatially-explicit statistical analysis was used to quantify the effects of nearby Bt and non-Bt cotton fields at various spatial scales, along with the effects of pollinator abundance and adventitious Bt plants in fields, on pollen-mediated gene flow. Adventitious Bt cotton plants, resulting from seed bags and planting error, comprised over 15% of plants sampled from the edges of three seed production fields. In contrast, pollen-mediated gene flow affected less than 1% of the seed sampled from field edges. Variation in outcrossing was better explained by the area of Bt cotton fields within 750 m of the seed production fields than by the area of Bt cotton within larger or smaller spatial scales. Variation in outcrossing was also positively associated with the abundance of honey bees. CONCLUSIONS/SIGNIFICANCE: A comparison of statistical methods showed that our spatially-explicit analysis was more powerful for understanding the effects of surrounding fields than customary models based on distance. Given the low rates of pollen-mediated gene flow observed in this study, we conclude that careful planting and screening of seeds could be more important than field spacing for limiting gene flow.

Identification of insecticide residues with a conducting-polymer electronic nose

Science.gov (United States)

A.D. Wilson

2014-01-01

The identification of insecticide residues on crop foliage is needed to make periodic pest management decisions. Electronic-nose (e-nose) methods were developed and tested as a means of acquiring rapid identifications of insecticide residue types at relatively low cost by detection of headspace volatiles released from inert surfaces in vitro. Detection methods were...

Flupyradifurone: a brief profile of a new butenolide insecticide

Science.gov (United States)

Nauen, Ralf; Jeschke, Peter; Velten, Robert; Beck, Michael E; Ebbinghaus-Kintscher, Ulrich; Thielert, Wolfgang; Wölfel, Katharina; Haas, Matthias; Kunz, Klaus; Raupach, Georg

2015-01-01

BACKGROUND The development and commercialisation of new chemical classes of insecticides for efficient crop protection measures against destructive invertebrate pests is of utmost importance to overcome resistance issues and to secure sustainable crop yields. Flupyradifurone introduced here is the first representative of the novel butenolide class of insecticides active against various sucking pests and showing an excellent safety profile. RESULTS The discovery of flupyradifurone was inspired by the butenolide scaffold in naturally occurring stemofoline. Flupyradifurone acts reversibly as an agonist on insect nicotinic acetylcholine receptors but is structurally different from known agonists, as shown by chemical similarity analysis. It shows a fast action on a broad range of sucking pests, as demonstrated in laboratory bioassays, and exhibits excellent field efficacy on a number of crops with different application methods, including foliar, soil, seed treatment and drip irrigation. It is readily taken up by plants and translocated in the xylem, as demonstrated by phosphor imaging analysis. Flupyradifurone is active on resistant pests, including cotton whiteflies, and is not metabolised by recombinantly expressed CYP6CM1, a cytochrome P450 conferring metabolic resistance to neonicotinoids and pymetrozine. CONCLUSION The novel butenolide insecticide flupyradifurone shows unique properties and will become a new tool for integrated pest management around the globe, as demonstrated by its insecticidal, ecotoxicological and safety profile. © 2014 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. PMID:25351824

Keeping the genie in the bottle: transgene biocontainment by excision in pollen.

Science.gov (United States)

Moon, Hong S; Li, Yi; Stewart, C Neal

2010-01-01

Gene flow from transgenic plants is an environmental and regulatory concern. While biocontainment might be achieved using male sterility or transgenic mitigation tools, we believe that perhaps the optimal solution might be simply to remove transgenes from pollen. Male sterility might not be ideal for many pollinators, and might not be implementable using standardized genes. Transgenic mitigation might not be useful to control conspecific gene flow (e.g. crop to crop), and relies on competition and not biocontainment per se. Site-specific recombination systems could allow highly efficient excision of transgenes in pollen to eliminate, or at least minimize, unwanted transgene movement via pollen dispersal. There are other potential biotechnologies, such as zinc finger nucleases, that could be also used for transgene excision.

The evolution of insecticide resistance in the peach potato aphid, Myzus persicae.

Science.gov (United States)

Bass, Chris; Puinean, Alin M; Zimmer, Christoph T; Denholm, Ian; Field, Linda M; Foster, Stephen P; Gutbrod, Oliver; Nauen, Ralf; Slater, Russell; Williamson, Martin S

2014-08-01

The peach potato aphid, Myzus persicae is a globally distributed crop pest with a host range of over 400 species including many economically important crop plants. The intensive use of insecticides to control this species over many years has led to populations that are now resistant to several classes of insecticide. Work spanning over 40 years has shown that M. persicae has a remarkable ability to evolve mechanisms that avoid or overcome the toxic effect of insecticides with at least seven independent mechanisms of resistance described in this species to date. The array of novel resistance mechanisms, including several 'first examples', that have evolved in this species represents an important case study for the evolution of insecticide resistance and also rapid adaptive change in insects more generally. In this review we summarise the biochemical and molecular mechanisms underlying resistance in M. persicae and the insights study of this topic has provided on how resistance evolves, the selectivity of insecticides, and the link between resistance and host plant adaptation. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

The responses of crop - wild Brassica hybrids to simulated herbivory and interspecific competition: implications for transgene introgression.

Science.gov (United States)

Sutherland, Jamie P; Justinova, Lenka; Poppy, Guy M

2006-01-01

Brassica rapa grows as a wild and weedy species throughout the world and is the most likely recipient of transgenes from GM oilseed rape. For transgene introgression to occur, the critical step which must be realized, is the formation of an F1 hybrid. Concerns exist that hybrid populations could be more vigorous and competitive compared to the parental species. This study examines the effect of simulated herbivory and interspecific competition on the vegetative and reproductive performance of non-transgenic F1 hybrids and their parental lines. Several vegetative and reproductive performance measures were used to determine the effect of simulated herbivory and competition on the Brassica lines, including leaf length and biomass for herbivory and seedling height and biomass for competition. For defoliation experiments, B. rapa showed little response in terms of leaf length but B. napus and the F1 hybrid responded negatively. Brassica rapa showed elevated biomass responses, but B. napus and the hybrid demonstrated negative responses to defoliation. Defoliation at the cotyledon stage had a slight effect upon final biomass with the F1 hybrid performing significantly worse than B. napus, although seed counts were not significantly different. For the series of competition experiments, hybrids seemed to be more similar to B. rapa in terms of early seedling growth and reproductive measures. The underperformance of hybrid plants when challenged by herbivory and competition, could potentially decrease survivorship and explain the rarity of hybrids in field surveys. However, should transgene introgression occur, the dynamics of hybrids could change radically thus increasing the risk of gene flow from a transgenic oilseed rape crop to the wild recipient.

Biotechnology network promotes knowledge of transgenics

International Nuclear Information System (INIS)

Blanco Picado, Patricia; Valdez Melara, Marta

2015-01-01

Red de Ingenieria Genetica Aplicada al Mejoramiento de Cultivos Tropicales (Rigatrop) integrated by a group of scientists from the Universidad de Costa Rica (UCR), Universidad Nacional (UNA) and of the Instituto Tecnologico de Costa Rica (TEC) have organized two forums on the topic of transgenics. The first forum has shown successful experiences of development of transgenic crops in Latin America, as for example: the transgenic bean, project realized in Brazil and transgenic eggplant in Bangladesh. The second forum has been about transgenics and environment effected at the UCR, on the occasion of World Environment Day. Rigatrop members are working currently in two projects applying biotechnological tools to coffee [es

Gut Microbiota Mediate Insecticide Resistance in the Diamondback Moth, Plutella xylostella (L.).

Science.gov (United States)

Xia, Xiaofeng; Sun, Botong; Gurr, Geoff M; Vasseur, Liette; Xue, Minqian; You, Minsheng

2018-01-01

The development of insecticide resistance in insect pests is a worldwide concern and elucidating the underlying mechanisms is critical for effective crop protection. Recent studies have indicated potential links between insect gut microbiota and insecticide resistance and these may apply to the diamondback moth, Plutella xylostella (L.), a globally and economically important pest of cruciferous crops. We isolated Enterococcus sp. (Firmicutes), Enterobacter sp. (Proteobacteria), and Serratia sp. (Proteobacteria) from the guts of P. xylostella and analyzed the effects on, and underlying mechanisms of insecticide resistance. Enterococcus sp. enhanced resistance to the widely used insecticide, chlorpyrifos, in P. xylostella , while in contrast, Serratia sp. decreased resistance and Enterobacter sp. and all strains of heat-killed bacteria had no effect. Importantly, the direct degradation of chlorpyrifos in vitro was consistent among the three strains of bacteria. We found that Enterococcus sp., vitamin C, and acetylsalicylic acid enhanced insecticide resistance in P. xylostella and had similar effects on expression of P. xylostella antimicrobial peptides. Expression of cecropin was down-regulated by the two compounds, while gloverin was up-regulated. Bacteria that were not associated with insecticide resistance induced contrasting gene expression profiles to Enterococcus sp. and the compounds. Our studies confirmed that gut bacteria play an important role in P. xylostella insecticide resistance, but the main mechanism is not direct detoxification of insecticides by gut bacteria. We also suggest that the influence of gut bacteria on insecticide resistance may depend on effects on the immune system. Our work advances understanding of the evolution of insecticide resistance in this key pest and highlights directions for research into insecticide resistance in other insect pest species.

Gut Microbiota Mediate Insecticide Resistance in the Diamondback Moth, Plutella xylostella (L.

Directory of Open Access Journals (Sweden)

Xiaofeng Xia

2018-01-01

Full Text Available The development of insecticide resistance in insect pests is a worldwide concern and elucidating the underlying mechanisms is critical for effective crop protection. Recent studies have indicated potential links between insect gut microbiota and insecticide resistance and these may apply to the diamondback moth, Plutella xylostella (L., a globally and economically important pest of cruciferous crops. We isolated Enterococcus sp. (Firmicutes, Enterobacter sp. (Proteobacteria, and Serratia sp. (Proteobacteria from the guts of P. xylostella and analyzed the effects on, and underlying mechanisms of insecticide resistance. Enterococcus sp. enhanced resistance to the widely used insecticide, chlorpyrifos, in P. xylostella, while in contrast, Serratia sp. decreased resistance and Enterobacter sp. and all strains of heat-killed bacteria had no effect. Importantly, the direct degradation of chlorpyrifos in vitro was consistent among the three strains of bacteria. We found that Enterococcus sp., vitamin C, and acetylsalicylic acid enhanced insecticide resistance in P. xylostella and had similar effects on expression of P. xylostella antimicrobial peptides. Expression of cecropin was down-regulated by the two compounds, while gloverin was up-regulated. Bacteria that were not associated with insecticide resistance induced contrasting gene expression profiles to Enterococcus sp. and the compounds. Our studies confirmed that gut bacteria play an important role in P. xylostella insecticide resistance, but the main mechanism is not direct detoxification of insecticides by gut bacteria. We also suggest that the influence of gut bacteria on insecticide resistance may depend on effects on the immune system. Our work advances understanding of the evolution of insecticide resistance in this key pest and highlights directions for research into insecticide resistance in other insect pest species.

Efficacy of insecticides in fruit borer control and residues on sugar apple fruit

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Alessandro da Silva Oliveira

Full Text Available ABSTRACT Bahia is the Brazilian state with the largest production of sugar apple fruits (Annona squamosa L., and fruit borer (Cerconota anonella, Sepp. 1830 is a key crop pest. Insecticides are the main strategy for pest control even though there are no pesticides registered for this crop. This study aimed to assess the efficacy of insecticides to control fruit borer and determine the levels of insecticide residues in sugar apple fruits aiming at requesting the extension of authorization to use insecticide products in this crop. The experiment was conducted in an eight-year-old irrigated orchard (2 × 4 m located in Anagé, Bahia, Brazil. The experimental design was a randomized block design with 10 treatments (three insecticides with three doses and a control with water and 5 replications. Each plot was composed of four plants but only the two central ones were assessed. Insecticides and doses (g a.i. 100 L−1 water were Bacillus thuringiensis: 0.8, 1.7, and 2.5; triflumuron: 2.4, 3.6, and 4.8; and imidacloprid: 4.0, 10.0, and 16.0. Nine sprayings were carried out at fortnightly intervals with a costal sprayer with constant pressure, JA-2 nozzle, and with jet directed to the fruits. Ten assessments were performed in order to observe fruit borer presence in 30 previously marked fruits per plot. Imidacloprid, at the highest studied dose, was the only effective treatment. Analyses of imidacloprid residues, at 21 and 30 days after the highest dose application, indicated levels higher than the maximum limit allowed. Insecticides under the conditions tested do not meet the norms for requesting the extension of authorization to use insecticides for citrus in sugar apple fruits.

Using corngrass1 to engineer poplar as a bioenergy crop

Energy Technology Data Exchange (ETDEWEB)

Meilan, Richard; Rubinelli, Peter Marius; Chuck, George

2016-05-10

Embodiments of the present invention relate generally to new bioenergy crops and methods of creating new bioenergy crops. For example, genes encoding microRNAs (miRNAs) are used to create transgenic crops. In some embodiments, over-expression of miRNA is used to produce transgenic perennials, such as trees, with altered lignin content or composition. In some embodiments, the transgenic perennials are Populus spp. In some embodiments, the miRNA is a member of the miR156 family. In some embodiments, the gene is Zea mays Cg1.

Pyrethrum flowers and pyrethroid insecticides.

OpenAIRE

Casida, J E

1980-01-01

The natural pyrethrins from the daisy-like flower, Tanacetum or Chrysanthemum cinerariifolium, are nonpersistent insecticides of low toxicity to mammals. Synthetic analogs or pyrethroids, evolved from the natural compounds by successive isosteric modifications, are more potent and stable and are the newest important class of crop protection chemicals. They retain many of the favorable properties of the pyrethrins.

Crop to wild introgression in lettuce: following the fate of crop genome segments in backcross populations

NARCIS (Netherlands)

Uwimana, B.; Smulders, M.J.M.; Hooftman, D.A.P.; Hartman, Y.; van Tienderen, P.H.; Jansen, J.; McHale, L.K.; Michelmore, R.W.; Visser, R.G.F.; van de Wiel, C.C.M.

2012-01-01

Background: After crop-wild hybridization, some of the crop genomic segments may become established in wild populations through selfing of the hybrids or through backcrosses to the wild parent. This constitutes a possible route through which crop (trans)genes could become established in natural

Crop to wild introgression in lettuce: following the fate of crop genome segments in backcross populations

NARCIS (Netherlands)

Uwimana, B.; Smulders, M.J.M.; Hooftman, D.A.P.; Hartman, Y.; Tienderen, van P.H.; Jansen, J.; McHale, L.K.; Michelmore, R.; Visser, R.G.F.; Wiel, van de C.C.M.

2012-01-01

After crop-wild hybridization, some of the crop genomic segments may become established in wild populations through selfing of the hybrids or through backcrosses to the wild parent. This constitutes a possible route through which crop (trans)genes could become established in natural populations. The

Assessing compositional variability through graphical analysis and Bayesian statistical approaches: case studies on transgenic crops.

Science.gov (United States)

Harrigan, George G; Harrison, Jay M

2012-01-01

New transgenic (GM) crops are subjected to extensive safety assessments that include compositional comparisons with conventional counterparts as a cornerstone of the process. The influence of germplasm, location, environment, and agronomic treatments on compositional variability is, however, often obscured in these pair-wise comparisons. Furthermore, classical statistical significance testing can often provide an incomplete and over-simplified summary of highly responsive variables such as crop composition. In order to more clearly describe the influence of the numerous sources of compositional variation we present an introduction to two alternative but complementary approaches to data analysis and interpretation. These include i) exploratory data analysis (EDA) with its emphasis on visualization and graphics-based approaches and ii) Bayesian statistical methodology that provides easily interpretable and meaningful evaluations of data in terms of probability distributions. The EDA case-studies include analyses of herbicide-tolerant GM soybean and insect-protected GM maize and soybean. Bayesian approaches are presented in an analysis of herbicide-tolerant GM soybean. Advantages of these approaches over classical frequentist significance testing include the more direct interpretation of results in terms of probabilities pertaining to quantities of interest and no confusion over the application of corrections for multiple comparisons. It is concluded that a standardized framework for these methodologies could provide specific advantages through enhanced clarity of presentation and interpretation in comparative assessments of crop composition.

Illegal gene flow from transgenic creeping bentgrass: the saga continues.

Science.gov (United States)

Snow, Allison A

2012-10-01

Ecologists have paid close attention to environmental effects that fitness-enhancing transgenes might have following crop-to-wild gene flow (e.g. Snow et al. 2003). For some crops, gene flow also can lead to legal problems,especially when government agencies have not approved transgenic events for unrestricted environmental release.Creeping bentgrass (Agrostis stolonifera), a common turf grass used in golf courses, is the focus of both areas of concern. In 2002, prior to expected deregulation (still pending), The Scotts Company planted creeping bentgrass with transgenic resistance to the herbicide glyphosate,also known as RoundUp, on 162 ha in a designated control area in central Oregon (Fig. 1).Despite efforts to restrict gene flow, wind-dispersed pollen carried transgenes to florets of local A. stolonifera and A. gigantea as far as 14 km away, and to sentinel plants placed as far as 21 km away (Watrud et al. 2004).Then, in August 2003, a strong wind event moved transgenic seeds from wind rows of cut bentgrass into nearby areas. The company’s efforts to kill all transgenic survivors in the area failed: feral glyphosate-resistant populations of A. stolonifera were found by Reichman et al.(2006), and 62% of 585 bentgrass plants had the telltale CP4 EPSPS transgene in 2006 (Zapiola et al. 2008; Fig. 2).Now, in this issue, the story gets even more interesting as Zapiola & Mallory-Smith (2012) describe a transgenic,intergeneric hybrid produced on a feral, transgenic creeping bentgrass plant that received pollen from Polypogon monspeliensis (rabbitfoot grass). Their finding raises a host of new questions about the prevalence and fitness of intergeneric hybrids, as well as how to evaluate the full extent of gene flow from transgenic crops.

RNA interference in designing transgenic crops.

Science.gov (United States)

Ali, Nusrat; Datta, Swapan K; Datta, Karabi

2010-01-01

RNA interference (RNAi) is a sequence specific gene silencing mechanism, triggered by the introduction of dsRNA leading to mRNA degradation. It helps in switching on and off the targeted gene, which might have significant impact in developmental biology. Discovery of RNAi represents one of the most promising and rapidly advancing frontiers in plant functional genomics and in crop improvement by plant metabolic engineering and also plays an important role in reduction of allergenicity by silencing specific plant allergens. In plants the RNAi technology has been employed successfully in improvement of several plant species- by increasing their nutritional value, overall quality and by conferring resistance against pathogens and diseases. The review gives an insight to the perspective use of the technology in designing crops with innovation, to bring improvement to crop productivity and quality.

Toxicity and poisoning symptoms of selected insecticides to honey bees (Apis mellifera mellifera L.

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Pashte Vrushali Vijaykumar

2018-01-01

Full Text Available Bees are potential pollinators of wide variety of crops. The European dark bee, Apis mellifera mellifera (L. is widely used for crop pollination. However, pesticide usage in modern agriculture has threatened the plant-bee pollinator interaction. There is lack of data regarding lethal time, insecticide concentration and poisoning symptoms, especially for formulated insecticides that are widely used in insect management. This study shows that the intrinsic toxicity of insecticides (LC50 to A. mellifera mellifera (L. was in the following order: imidacloprid (0.0070 > fipronil (0.0125 > indoxacarb (0.0266> cypermethrin (0.0370 > dimethoate (0.0385. The lethal time (LT50 values (h in the ascending order of toxicity of insecticides were as follows: fipronil (6.56, cypermethrin (6.69, dimethoate (8.00, imidacloprid (9.85 and indoxacarb (13.45. Distinct poisoning symptoms observed in A. mellifera mellifera were extended proboscis, expanded wings, unhooked wings, extended legs and twisted bodies, defecation on cage covers, sting in release-out position and anus with excreta. All the tested pesticides are harmful to the honey bee except azadirachtin. The tested pesticides exhibited different poisoning symptoms in bees, which could be useful for beekeepers in identifying the cause of colony mortality. In conclusion, the pesticide toxicological research on bees is an important safety aspect for beneficial organisms. This study reveals a realistic acute toxicity in the field of commonly used insecticides. The information is important for insecticide selection in order to minimize direct killing of foraging honey bees while maintaining effective management of crop pests.

Hybridization between crops and wild relatives: the contribution of cultivated lettuce to the vigour of crop-wild hybrids under drought, salinity and nutrient deficiency conditions

NARCIS (Netherlands)

Uwimana, B.; Smulders, M.J.M.; Hooftman, D.A.P.; Hartman, Y.; Tienderen, van P.H.; Jansen, J.; McHale, L.K.; Michelmore, R.W.; Wiel, van de C.C.M.; Visser, R.G.F.

2012-01-01

With the development of transgenic crop varieties, crop–wild hybridization has received considerable consideration with regard to the potential of transgenes to be transferred to wild species. Although many studies have shown that crops can hybridize with their wild relatives and that the resulting

Neonicotinoid insecticide removal by prairie strips in row-cropped watersheds with historical seed coating use

Science.gov (United States)

Hladik, Michelle L.; Bradbury, Steven; Schulte, Lisa A.; Helmers, Matthew; Witte, Christopher; Kolpin, Dana W.; Garrett, Jessica D.; Harris, Mary

2017-01-01

Neonicotinoids are a widely used class of insecticides that are commonly applied as seed coatings for agricultural crops. Such neonicotinoid use may pose a risk to non-target insects, including pollinators and natural enemies of crop pests, and ecosystems. This study assessed neonicotinoid residues in groundwater, surface runoff water, soil, and native plants adjacent to corn and soybean crop fields with a history of being planted with neonicotinoid-treated seeds from 2008-2013. Data from six sites with the same crop management history, three with and three without in-field prairie strips, were collected in 2015-2016, 2-3 years after neonicotinoid (clothianidin and imidacloprid) seed treatments were last used. Three of the six neonicotinoids analyzed were detected in at least one environmental matrix: the two applied as seed coatings on the fields (clothianidin and imidacloprid) and another widely used neonicotinoid (thiamethoxam). Sites with prairie strips generally had lower concentrations of neonicotinoids: groundwater and footslope soil neonicotinoid concentrations were significantly lower in the sites with prairie strips than those without; mean concentrations for groundwater were 11 and 20 ng/L (p = 0.048) and <1 and 6 ng/g (p = 0.0004) for soil, respectively. Surface runoff water concentrations were not significantly (p = 0.38) different for control sites (44 ng/L) or sites with prairie strips (140 ng/L). Consistent with the decreased inputs of neonicotinoids, concentrations tended to decrease over the sampling timeframe. Two sites recorded concentration increases, however, potentially due to disturbance of previous applications or influence from nearby fields where use of seed treatments continued. There were no detections (limit of detection: 1 ng/g) of neonicotinoids in the foliage or roots of plants comprising prairie strips, indicating a low likelihood of exposure to pollinators and other insects visiting these plants following the cessation of seed

A bioinformatics approach for identifying transgene insertion sites using whole genome sequencing data.

Science.gov (United States)

Park, Doori; Park, Su-Hyun; Ban, Yong Wook; Kim, Youn Shic; Park, Kyoung-Cheul; Kim, Nam-Soo; Kim, Ju-Kon; Choi, Ik-Young

2017-08-15

Genetically modified crops (GM crops) have been developed to improve the agricultural traits of modern crop cultivars. Safety assessments of GM crops are of paramount importance in research at developmental stages and before releasing transgenic plants into the marketplace. Sequencing technology is developing rapidly, with higher output and labor efficiencies, and will eventually replace existing methods for the molecular characterization of genetically modified organisms. To detect the transgenic insertion locations in the three GM rice gnomes, Illumina sequencing reads are mapped and classified to the rice genome and plasmid sequence. The both mapped reads are classified to characterize the junction site between plant and transgene sequence by sequence alignment. Herein, we present a next generation sequencing (NGS)-based molecular characterization method, using transgenic rice plants SNU-Bt9-5, SNU-Bt9-30, and SNU-Bt9-109. Specifically, using bioinformatics tools, we detected the precise insertion locations and copy numbers of transfer DNA, genetic rearrangements, and the absence of backbone sequences, which were equivalent to results obtained from Southern blot analyses. NGS methods have been suggested as an effective means of characterizing and detecting transgenic insertion locations in genomes. Our results demonstrate the use of a combination of NGS technology and bioinformatics approaches that offers cost- and time-effective methods for assessing the safety of transgenic plants.

Response difference of transgenic and conventional rice (Oryza sativa) to nanoparticles (γFe₂O₃).

Science.gov (United States)

Gui, Xin; Deng, Yingqing; Rui, Yukui; Gao, Binbin; Luo, Wenhe; Chen, Shili; Nhan, Le Van; Li, Xuguang; Liu, Shutong; Han, Yaning; Liu, Liming; Xing, Baoshan

2015-11-01

Nanoparticles (NPs) are an increasingly common contaminant in agro-environments, and their potential effect on genetically modified (GM) crops has been largely unexplored. GM crop exposure to NPs is likely to increase as both technologies develop. To better understand the implications of nanoparticles on GM plants in agriculture, we performed a glasshouse study to quantify the uptake of Fe2O3 NPs on transgenic and non-transgenic rice plants. We measured nutrient concentrations, biomass, enzyme activity, and the concentration of two phytohormones, abscisic acid (ABA) and indole-3-acetic acid (IAA), and malondialdehyde (MDA). Root phytohormone inhibition was positively correlated with Fe2O3 NP concentrations, indicating that Fe2O3 had a significant influence on the production of these hormones. The activities of antioxidant enzymes were significantly higher as a factor of low Fe2O3 NP treatment concentration and significantly lower at high NP concentrations, but only among transgenic plants. There was also a positive correlation between the treatment concentration of Fe2O3 and iron accumulation, and the magnitude of this effect was greatest among non-transgenic plants. The differences in root phytohormone production and antioxidant enzyme activity between transgenic and non-transgenic rice plants in vivo suggests that GM crops may react to NP exposure differently than conventional crops. It is the first study of NPs that may have an impact on GM crops, and a realistic significance for food security and food safety.

Histopathological Effects of Bt and TcdA Insecticidal Proteins on the Midgut Epithelium of Western Corn Rootworm Larvae (Diabrotica virgifera virgifera

Directory of Open Access Journals (Sweden)

Andrew J. Bowling

2017-05-01

Full Text Available Western corn rootworm (WCR, Diabrotica virgifera virgifera LeConte is a major corn pest in the United States, causing annual losses of over $1 billion. One approach to protect against crop loss by this insect is the use of transgenic corn hybrids expressing one or more crystal (Cry proteins derived from Bacillus thuringiensis. Cry34Ab1 and Cry35Ab1 together comprise a binary insecticidal toxin with specific activity against WCR. These proteins have been developed as insect resistance traits in commercialized corn hybrids resistant to WCR feeding damage. Cry34/35Ab1 is a pore forming toxin, but the specific effects of Cry34/35Ab1 on WCR cells and tissues have not been well characterized microscopically, and the overall histopathology is poorly understood. Using high-resolution resin-based histopathology methods, the effects of Cry34/35Ab1 as well as Cry3Aa1, Cry6Aa1, and the Photorhabdus toxin complex protein TcdA have been directly visualized and documented. Clear symptoms of intoxication were observed for all insecticidal proteins tested, including swelling and sloughing of enterocytes, constriction of midgut circular muscles, stem cell activation, and obstruction of the midgut lumen. These data demonstrate the effects of these insecticidal proteins on WCR midgut cells, and the collective response of the midgut to intoxication. Taken together, these results advance our understanding of the insect cell biology and pathology of these insecticidal proteins, which should further the field of insect resistance traits and corn rootworm management.

Climate change, agricultural insecticide exposure, and risk for freshwater communities.

Science.gov (United States)

Kattwinkel, Mira; Kühne, Jan-Valentin; Foit, Kaarina; Liess, Matthias

2011-09-01

Climate change exerts direct effects on ecosystems but has additional indirect effects due to changes in agricultural practice. These include the increased use of pesticides, changes in the areas that are cultivated, and changes in the crops cultivated. It is well known that pesticides, and in particular insecticides, affect aquatic ecosystems adversely. To implement effective mitigation measures it is necessary to identify areas that are affected currently and those that will be affected in the future. As a consequence, we predicted potential exposure to insecticide (insecticide runoff potential, RP) under current conditions (1990) and under a model scenario of future climate and land use (2090) using a spatially explicit model on a continental scale, with a focus on Europe. Space-for-time substitution was used to predict future levels of insecticide application, intensity of agricultural land use, and cultivated crops. To assess the indirect effects of climate change, evaluation of the risk of insecticide exposure was based on a trait-based, climate-insensitive indicator system (SPEAR, SPEcies At Risk). To this end, RP and landscape characteristics that are relevant for the recovery of affected populations were combined to estimate the ecological risk (ER) of insecticides for freshwater communities. We predicted a strong increase in the application of, and aquatic exposure to, insecticides under the future scenario, especially in central and northern Europe. This, in turn, will result in a severe increase in ER in these regions. Hence, the proportion of stream sites adjacent to arable land that do not meet the requirements for good ecological status as defined by the EU Water Framework Directive will increase (from 33% to 39% for the EU-25 countries), in particular in the Scandinavian and Baltic countries (from 6% to 19%). Such spatially explicit mapping of risk enables the planning of adaptation and mitigation strategies including vegetated buffer strips and

Expression of BrD1, a plant defensin from Brassica rapa, confers resistance against brown planthopper (Nilaparvata lugens) in transgenic rices.

Science.gov (United States)

Choi, Man-Soo; Kim, Yul-Ho; Park, Hyang-Mi; Seo, Bo-Yoon; Jung, Jin-Kyo; Kim, Sun-Tae; Kim, Min-Chul; Shin, Dong-Bum; Yun, Hong-Tai; Choi, Im-Soo; Kim, Chung-Kon; Lee, Jang-Yong

2009-08-31

Plant defensins are small (5-10 kDa) basic peptides thought to be an important component of the defense pathway against fungal and/or bacterial pathogens. To understand the role of plant defensins in protecting plants against the brown planthopper, a type of insect herbivore, we isolated the Brassica rapa Defensin 1 (BrD1) gene and introduced it into rice (Oryza sativa L.) to produce stable transgenic plants. The BrD1 protein is homologous to other plant defensins and contains both an N-terminal endoplasmic reticulum signal sequence and a defensin domain, which are highly conserved in all plant defensins. Based on a phylogenetic analysis of the defensin domain of various plant defensins, we established that BrD1 belongs to a distinct subgroup of plant defensins. Relative to the wild type, transgenic rices expressing BrD1 exhibit strong resistance to brown planthopper nymphs and female adults. These results suggest that BrD1 exhibits insecticidal activity, and might be useful for developing cereal crop plants resistant to sap-sucking insects, such as the brown planthopper.

Production of transgenic brassica juncea with the synthetic chitinase gene (nic) conferring resistance to alternaria brassicicola

International Nuclear Information System (INIS)

Munir, I.; Hussan, W.; Kazi, M.; Mian, A.

2016-01-01

Brassica juncea is an important oil seed crop throughout the world. The demand and cultivation of oil seed crops has gained importance due to rapid increase in world population and industrialization. Fungal diseases pose a great threat to Brassica productivity worldwide. Absence of resistance genes against fungal infection within crossable germplasms of this crop necessitates deployment of genetic engineering approaches to produce transgenic plants with resistance against fungal infections. In the current study, hypocotyls and cotyledons of Brassica juncea, used as explants, were transformed with Agrobacterium tumefacien strain EHA101 harboring binary vector pEKB/NIC containing synthetic chitinase gene (NIC), an antifungal gene under the control of cauliflower mosaic virus promoter (CaMV35S). Bar genes and nptII gene were used as selectable markers. Presence of chitinase gene in trangenic lines was confirmed by PCR and southern blotting analysis. Effect of the extracted proteins from non-transgenic and transgenic lines was observed on the growth of Alternaria brassicicola, a common disease causing pathogen in brassica crop. In comparison to non-transgenic control lines, the leaf tissue extracts of the transgenic lines showed considerable resistance and antifungal activity against A. brassicicola. The antifungal activity in transgenic lines was observed as corresponding to the transgene copy number. (author)

Disentangling determinants of insecticide use to manage production, food security, and health risks in Cambodia and Vietnam: evidence from household surveys and risk-assessment experiments

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Wei Zhang, PhD

2018-05-01

Full Text Available Background: Insect pest problems are among the main causes of crop yield losses in global agriculture. Insecticides protect households from food-security and income shocks, but can induce human health and environmental risks. Semi-subsistence farm households (SSFHs, which farm for both consumption and market, make decisions about crop management and output allocation to maximise food consumption, income, and health outcomes, depending on their risk preferences and other household and community characteristics. In this study, we aimed to disentangle the determinants of insecticide use by SSFHs and identify whether health consideration has had any effect on insecticide use. Methods: In this econometric analysis, we used field data collected from household surveys and risk-assessment experiments in 2014 in Cambodia and Vietnam to analyse insecticide use among more than 1000 SSFHs. Findings: We found that crops (except for rice whose outputs were used to a greater degree for consumption were less likely to be sprayed with insecticides or were sprayed fewer times. Health-conscious households (as indicated by the use of modern-fuel cooking stoves and reported concern over food safety as a main reason for maintaining home gardens consistently refrained from spraying, but this tendency diminished as output allocation shifted toward commercial use, suggesting a possible moral-hazard phenomenon. Farmers were more likely to apply insecticides to crops of high food security or dietary importance, such as rice, although the difference between fresh produce and grain produce in risk of insecticide residue exposure might also have contributed to the difference in insecticide use between rice and non-rice crops. The two samples from Cambodia and Vietnam had similarities regarding the deterring effect of health consideration and differences in other factors affecting insecticide use, such as risk preference, landholding size, household head's education level

Crop to wild introgression in lettuce: following the fate of crop genome segments in backcross populations.

Science.gov (United States)

Uwimana, Brigitte; Smulders, Marinus J M; Hooftman, Danny A P; Hartman, Yorike; van Tienderen, Peter H; Jansen, Johannes; McHale, Leah K; Michelmore, Richard W; Visser, Richard G F; van de Wiel, Clemens C M

2012-03-26

After crop-wild hybridization, some of the crop genomic segments may become established in wild populations through selfing of the hybrids or through backcrosses to the wild parent. This constitutes a possible route through which crop (trans)genes could become established in natural populations. The likelihood of introgression of transgenes will not only be determined by fitness effects from the transgene itself but also by the crop genes linked to it. Although lettuce is generally regarded as self-pollinating, outbreeding does occur at a low frequency. Backcrossing to wild lettuce is a likely pathway to introgression along with selfing, due to the high frequency of wild individuals relative to the rarely occurring crop-wild hybrids. To test the effect of backcrossing on the vigour of inter-specific hybrids, Lactuca serriola, the closest wild relative of cultivated lettuce, was crossed with L. sativa and the F(1) hybrid was backcrossed to L. serriola to generate BC(1) and BC(2) populations. Experiments were conducted on progeny from selfed plants of the backcrossing families (BC(1)S(1) and BC(2)S(1)). Plant vigour of these two backcrossing populations was determined in the greenhouse under non-stress and abiotic stress conditions (salinity, drought, and nutrient deficiency). Despite the decreasing contribution of crop genomic blocks in the backcross populations, the BC(1)S(1) and BC(2)S(1) hybrids were characterized by a substantial genetic variation under both non-stress and stress conditions. Hybrids were identified that performed equally or better than the wild genotypes, indicating that two backcrossing events did not eliminate the effect of the crop genomic segments that contributed to the vigour of the BC(1) and BC(2) hybrids. QTLs for plant vigour under non-stress and the various stress conditions were detected in the two populations with positive as well as negative effects from the crop. As it was shown that the crop contributed QTLs with either a positive

Crop to wild introgression in lettuce: following the fate of crop genome segments in backcross populations

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Uwimana Brigitte

2012-03-01

Full Text Available Abstract Background After crop-wild hybridization, some of the crop genomic segments may become established in wild populations through selfing of the hybrids or through backcrosses to the wild parent. This constitutes a possible route through which crop (transgenes could become established in natural populations. The likelihood of introgression of transgenes will not only be determined by fitness effects from the transgene itself but also by the crop genes linked to it. Although lettuce is generally regarded as self-pollinating, outbreeding does occur at a low frequency. Backcrossing to wild lettuce is a likely pathway to introgression along with selfing, due to the high frequency of wild individuals relative to the rarely occurring crop-wild hybrids. To test the effect of backcrossing on the vigour of inter-specific hybrids, Lactuca serriola, the closest wild relative of cultivated lettuce, was crossed with L. sativa and the F1 hybrid was backcrossed to L. serriola to generate BC1 and BC2 populations. Experiments were conducted on progeny from selfed plants of the backcrossing families (BC1S1 and BC2S1. Plant vigour of these two backcrossing populations was determined in the greenhouse under non-stress and abiotic stress conditions (salinity, drought, and nutrient deficiency. Results Despite the decreasing contribution of crop genomic blocks in the backcross populations, the BC1S1 and BC2S1 hybrids were characterized by a substantial genetic variation under both non-stress and stress conditions. Hybrids were identified that performed equally or better than the wild genotypes, indicating that two backcrossing events did not eliminate the effect of the crop genomic segments that contributed to the vigour of the BC1 and BC2 hybrids. QTLs for plant vigour under non-stress and the various stress conditions were detected in the two populations with positive as well as negative effects from the crop. Conclusion As it was shown that the crop

Crop to wild introgression in lettuce: following the fate of crop genome segments in backcross populations

Science.gov (United States)

2012-01-01

Background After crop-wild hybridization, some of the crop genomic segments may become established in wild populations through selfing of the hybrids or through backcrosses to the wild parent. This constitutes a possible route through which crop (trans)genes could become established in natural populations. The likelihood of introgression of transgenes will not only be determined by fitness effects from the transgene itself but also by the crop genes linked to it. Although lettuce is generally regarded as self-pollinating, outbreeding does occur at a low frequency. Backcrossing to wild lettuce is a likely pathway to introgression along with selfing, due to the high frequency of wild individuals relative to the rarely occurring crop-wild hybrids. To test the effect of backcrossing on the vigour of inter-specific hybrids, Lactuca serriola, the closest wild relative of cultivated lettuce, was crossed with L. sativa and the F1 hybrid was backcrossed to L. serriola to generate BC1 and BC2 populations. Experiments were conducted on progeny from selfed plants of the backcrossing families (BC1S1 and BC2S1). Plant vigour of these two backcrossing populations was determined in the greenhouse under non-stress and abiotic stress conditions (salinity, drought, and nutrient deficiency). Results Despite the decreasing contribution of crop genomic blocks in the backcross populations, the BC1S1 and BC2S1 hybrids were characterized by a substantial genetic variation under both non-stress and stress conditions. Hybrids were identified that performed equally or better than the wild genotypes, indicating that two backcrossing events did not eliminate the effect of the crop genomic segments that contributed to the vigour of the BC1 and BC2 hybrids. QTLs for plant vigour under non-stress and the various stress conditions were detected in the two populations with positive as well as negative effects from the crop. Conclusion As it was shown that the crop contributed QTLs with either a

Transgenic Expression of a Functional Fragment of Harpin Protein Hpa1 in Wheat Represses English Grain Aphid Infestation

Institute of Scientific and Technical Information of China (English)

XU Man-yu; ZHOU Ting; ZHAO Yan-ying; LI Jia-bao; XU Heng; DONG Han-song; ZHANG Chun-ling

2014-01-01

The harpin protein Hpa1 produced by the rice bacterial blight pathogen promotes plant growth and induces plant resistance to pathogens and insect pests. The region of 10-42 residues (Hpa110-42) in the Hpa1 sequence is critical as the isolated Hpa110-42 fragment is 1.3-7.5-fold more effective than the full length in inducing plant growth and resistance. Here we report that transgenic expression of Hpa110-42 in wheat induces resistance to English grain aphid, a dominant species of wheat aphids. Hpa110-42-induced resistance is effective to inhibit the aphid behavior in plant preference at the initial colonization stage and repress aphid performances in the reproduction, nymph growth, and instar development on transgenic plants. The resistance characters are correlated with enhanced expression of defense-regulatory genes (EIN2, PP2-A, and GSL10) and consistent with induced expression of defense response genes (Hel, PDF1.2, PR-1b, and PR-2b). As a result, aphid infestations are alleviated in transgenic plants. The level of Hpa110-42-induced resistance in regard to repression of aphid infestations is equivalent to the effect of chemical control provided by an insecticide. These results suggested that the defensive role of Hpa110-42 can be integrated into breeding germplasm of the agriculturally signiifcant crop with a great potential of the agricultural application.

Precise, flexible and affordable gene stacking for crop improvement.

Science.gov (United States)

Chen, Weiqiang; Ow, David W

2017-09-03

The genetic engineering of plants offers a revolutionary advance for crop improvement, and the incorporation of transgenes into crop species can impart new traits that would otherwise be difficult to obtain through conventional breeding. Transgenes introduced into plants, however, can only be useful when bred out to field cultivars. As new traits are continually added to further improve transgenic cultivars, clustering new DNA near previously introduced transgenes keep from inflating the number of segregating units that breeders must assemble back into a breeding line. Here we discuss various options to introduce DNA site-specifically into an existing transgenic locus. As food security is becoming a pressing global issue, the old proverb resonates true to this day: "give a man a fish and you feed him for a day; teach a man to fish and you feed him for a lifetime." Hence, we describe a recombinase-mediate gene stacking system designed with freedom to operate, providing an affordable option for crop improvement by less developed countries where food security is most at risk.

Photo-biotechnology as a tool to improve agronomic traits in crops.

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Gururani, Mayank Anand; Ganesan, Markkandan; Song, Pill-Soon

2015-01-01

Phytochromes are photosensory phosphoproteins with crucial roles in plant developmental responses to light. Functional studies of individual phytochromes have revealed their distinct roles in the plant's life cycle. Given the importance of phytochromes in key plant developmental processes, genetically manipulating phytochrome expression offers a promising approach to crop improvement. Photo-biotechnology refers to the transgenic expression of phytochrome transgenes or variants of such transgenes. Several studies have indicated that crop cultivars can be improved by modulating the expression of phytochrome genes. The improved traits include enhanced yield, improved grass quality, shade-tolerance, and stress resistance. In this review, we discuss the transgenic expression of phytochrome A and its hyperactive mutant (Ser599Ala-PhyA) in selected crops, such as Zoysia japonica (Japanese lawn grass), Agrostis stolonifera (creeping bentgrass), Oryza sativa (rice), Solanum tuberosum (potato), and Ipomea batatas (sweet potato). The transgenic expression of PhyA and its mutant in various plant species imparts biotechnologically useful traits. Here, we highlight recent advances in the field of photo-biotechnology and review the results of studies in which phytochromes or variants of phytochromes were transgenically expressed in various plant species. We conclude that photo-biotechnology offers an excellent platform for developing crops with improved properties. Copyright © 2014 Elsevier Inc. All rights reserved.

Genetic transformation of cry1EC gene into cotton ( Gossypium ...

African Journals Online (AJOL)

Cotton is the chief fibre crop of global importance. It plays a significant role in the national economy. Cotton crop is vulnerable to a number of insect species, especially to the larvae of lepidopteron pests. 60% insecticides sprayed on cotton are meant to control the damage caused by bollworm complex. Transgenic ...

DNA barcoding simplifies environmental risk assessment of genetically modified crops in biodiverse regions.

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Chinyere V Nzeduru

Full Text Available Transgenes encoding for insecticidal crystal (Cry proteins from the soil-dwelling bacterium Bacillus Thuringiensis have been widely introduced into Genetically Modified (GM crops to confer protection against insect pests. Concern that these transgenes may also harm beneficial or otherwise valued insects (so-called Non Target Organisms, NTOs represents a major element of the Environmental Risk Assessments (ERAs used by all countries prior to commercial release. Compiling a comprehensive list of potentially susceptible NTOs is therefore a necessary part of an ERA for any Cry toxin-containing GM crop. In partly-characterised and biodiverse countries, NTO identification is slowed by the need for taxonomic expertise and time to enable morphological identifications. This limitation represents a potentially serious barrier to timely adoption of GM technology in some developing countries. We consider Bt Cry1A cowpea (Vigna unguiculata in Nigeria as an exemplar to demonstrate how COI barcoding can provide a simple and cost-effective means of addressing this problem. Over a period of eight weeks, we collected 163 insects from cowpea flowers across the agroecological and geographic range of the crop in Nigeria. These individuals included 32 Operational Taxonomic Units (OTUs spanning four Orders and that could mostly be assigned to genus or species level. They included 12 Lepidopterans and two Coleopterans (both potentially sensitive to different groups of Cry proteins. Thus, barcode-assisted diagnoses were highly harmonised across groups (typically to genus or species level and so were insensitive to expertise or knowledge gaps. Decisively, the entire study was completed within four months at a cost of less than 10,000 US$. The broader implications of the findings for food security and the capacity for safe adoption of GM technology are briefly explored.

[Transformation and expression of specific insecticide gene Bt cry3A in resident endogenetic bacteria isolated from Apriona germari (Hope) larvae intestines].

Science.gov (United States)

Zhongkang, Wang; Wei, He; Guoxiong, Peng; Yuxian, Xia; Qiang, Li; Youping, Yin

2008-09-01

Transforming the specific insecticidal gene Bt cry3A into the dominant resident endogenetic bacteria in intestines of Apriona germari (Hope) larvae to construct transgenic bacteria that can colonize and express the insecticidal gene Bt cry3A perfectly in intestines of Apriona germari (Hope) larvae. We isolated and identified the dominant resident endogenetic bacteria by traditional methods and molecular method based of 16S rDNA analysis. Two Escherichia coli--Bacillus thuringiensis shuttle plasmid pHT305a and pHT7911 which contained specific insecticidal gene Bt cry3A were transformed into two resident endogenetic bacteria Brevibacillus brevis Ag12 and Bacillus thuringiensis Ag13 isolated from A. germari larvae intestines respectively by electro-transformation. Eighteen species of bacteria have isolated and identified from Apriona germari larvae intestines and two of them (Brevibacillus brevis Ag12 and Bacillus thuringiensis Ag13) were selected as starting bacteria to recieve the Bt cry3A. The 4 transgenic engineering strains Ag12-7911, Ag12-305a, Ag13-7911 and Ag13-305a were obtained successfully and validated by testing the plasmid stability in recombinants, transformants vegetal properties, crystal poisonous protein observation, expressional protein SDS-PAGE. The Bt cry3A gene had been transformed into Brevibacillus brevis and Bacillus thuringiensis. Both bioassay and examination of the engineering strains in intestines after feeding them to larvae showed that all these transformant strains (Brevibacillus brevis Ag12-305a, Bacillus thurigiensis Ag13-305a, Brevibacillus brevis Ag12-7911 and Bacillus thurigiensis Ag13-7911) could colonize and express 65 kDa protoxin in intestines of A. germari larvae and had insecticidal activity. We obtained four transgenic bacteria that can colonize and express the target insecticide gene Bt cry3A in A. germari larvae. They may be developed as a new insecticide.

1978 Insect Pest Management Guide: Field and Forage Crops. Circular 899.

Science.gov (United States)

Illinois Univ., Urbana. Cooperative Extension Service.

This circular lists suggested uses of insecticides for the control of field crop pests. Suggestions are given for selection, dosage and application of insecticides to control pests in field corn, alfalfa and clover, small grains, soybeans and grain sorghum. (CS)

Multiple transgene traits may create un-intended fitness effects in Brassica napus

Science.gov (United States)

Increasingly, genetically modified crops are being developed to express multiple “stacked” traits for different types of transgenes, for example, herbicide resistance, insect resistance, crop quality and resistance to environmental factors. The release of crops that express mult...

Novel and viable acetylcholinesterase target site for developing effective and environmentally safe insecticides.

Science.gov (United States)

Pang, Yuan-Ping; Brimijoin, Stephen; Ragsdale, David W; Zhu, Kun Yan; Suranyi, Robert

2012-04-01

Insect pests are responsible for human suffering and financial losses worldwide. New and environmentally safe insecticides are urgently needed to cope with these serious problems. Resistance to current insecticides has resulted in a resurgence of insect pests, and growing concerns about insecticide toxicity to humans discourage the use of insecticides for pest control. The small market for insecticides has hampered insecticide development; however, advances in genomics and structural genomics offer new opportunities to develop insecticides that are less dependent on the insecticide market. This review summarizes the literature data that support the hypothesis that an insect-specific cysteine residue located at the opening of the acetylcholinesterase active site is a promising target site for developing new insecticides with reduced off-target toxicity and low propensity for insect resistance. These data are used to discuss the differences between targeting the insect-specific cysteine residue and targeting the ubiquitous catalytic serine residue of acetylcholinesterase from the perspective of reducing off-target toxicity and insect resistance. Also discussed is the prospect of developing cysteine-targeting anticholinesterases as effective and environmentally safe insecticides for control of disease vectors, crop damage, and residential insect pests within the financial confines of the present insecticide market.

Genomic regions under selection in crop-wild hybrids of lettuce: implications for crop breeding and environmental risk assessment

NARCIS (Netherlands)

Hartman, Y.

2012-01-01

The results of this thesis show that the probability of introgression of a putative transgene to wild relatives indeed depends strongly on the insertion location of the transgene. The study of genomic selection patterns can identify crop genomic regions under negative selection in multiple

Cost of soybean crop yield transgenic in Goias ( crop 2015/2016 equity x third capital

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Sidney Jordan Silva

2016-06-01

Full Text Available Considering the data from the Ministry of Agriculture, in 2014 the Gross Domestic Product - Brazilian agricultural GDP accounted for about 23% of the total GDP of the Brazilian economy, in reais equivalent to R $ 1.1 trillion. And within it agriculture is represented in 70% of the production of agribusiness. Seen it, one sees Brazil's potential in this activity. Therefore, it is evident that this Montate production needs to be managed throughout the production cycle. This includes as a first step planting, a fact that needs initial investment to allow the harvest to the end of the process. Because of this it was thought what are the ways to start agricultural production. This work specifically measured the transgenic soybean crop in the state of Goiás. The source of the resource that defrayed the cost of production was studied. It found that can be made via bank through a rural financing or financing with own resources, considering that the farmer has this option when you start your planting. If the producer utilizasse own resources he would not receive the full amount calculated the profitability of Agribusiness Credit Bills - LCA. By financing the farmer will pay only the interest calculated if using all capital financed the formalization of the contract. And taking into account that the cost of financing ranges from planting to harvest, if the releases are gradually made the producer may also reduce the interest to be paid.

Engineering insect-resistant crops: A review

African Journals Online (AJOL)

dgeorge

African Journal of Biotechnology ... Transgenic crops engineered for enhanced levels of resistance to insect ... this background that research work targeting other candidate genes such as ... nisms, and potential deleterious environmental effects. ... The global market value of biotech crops was esti- .... located in repeat 11.

Insecticide use and practices among cotton farmers in northern ...

African Journals Online (AJOL)

Cotton (Gossypium hirsutum L.) is an important cash crop in Uganda. Insecticide application practices among cotton growers in northern Uganda were examined to determine the pests targeted and the compliance of control measures with the standards recommended by the Uganda's Cotton Development Organization ...

Engineering insect-resistant crops: A review | George | African ...

African Journals Online (AJOL)

Insect pests cause significant damage to crops world-wide. This is despite integrated pest management strategies combining such control measures as chemical control, use of resistant varieties and other measures. Other control measures such as use of genetically modified crops are being adopted. Transgenic crops ...

Seed coating with a neonicotinoid insecticide negatively affects wild bees.

Science.gov (United States)

Rundlöf, Maj; Andersson, Georg K S; Bommarco, Riccardo; Fries, Ingemar; Hederström, Veronica; Herbertsson, Lina; Jonsson, Ove; Klatt, Björn K; Pedersen, Thorsten R; Yourstone, Johanna; Smith, Henrik G

2015-05-07

Understanding the effects of neonicotinoid insecticides on bees is vital because of reported declines in bee diversity and distribution and the crucial role bees have as pollinators in ecosystems and agriculture. Neonicotinoids are suspected to pose an unacceptable risk to bees, partly because of their systemic uptake in plants, and the European Union has therefore introduced a moratorium on three neonicotinoids as seed coatings in flowering crops that attract bees. The moratorium has been criticized for being based on weak evidence, particularly because effects have mostly been measured on bees that have been artificially fed neonicotinoids. Thus, the key question is how neonicotinoids influence bees, and wild bees in particular, in real-world agricultural landscapes. Here we show that a commonly used insecticide seed coating in a flowering crop can have serious consequences for wild bees. In a study with replicated and matched landscapes, we found that seed coating with Elado, an insecticide containing a combination of the neonicotinoid clothianidin and the non-systemic pyrethroid β-cyfluthrin, applied to oilseed rape seeds, reduced wild bee density, solitary bee nesting, and bumblebee colony growth and reproduction under field conditions. Hence, such insecticidal use can pose a substantial risk to wild bees in agricultural landscapes, and the contribution of pesticides to the global decline of wild bees may have been underestimated. The lack of a significant response in honeybee colonies suggests that reported pesticide effects on honeybees cannot always be extrapolated to wild bees.

Alternatives to neonicotinoid insecticides for pest control: case studies in agriculture and forestry.

Science.gov (United States)

Furlan, Lorenzo; Kreutzweiser, David

2015-01-01

Neonicotinoid insecticides are widely used for control of insect pests around the world and are especially pervasive in agricultural pest management. There is a growing body of evidence indicating that the broad-scale and prophylactic uses of neonicotinoids pose serious risks of harm to beneficial organisms and their ecological function. This provides the impetus for exploring alternatives to neonicotinoid insecticides for controlling insect pests. We draw from examples of alternative pest control options in Italian maize production and Canadian forestry to illustrate the principles of applying alternatives to neonicotinoids under an integrated pest management (IPM) strategy. An IPM approach considers all relevant and available information to make informed management decisions, providing pest control options based on actual need. We explore the benefits and challenges of several options for management of three insect pests in maize crops and an invasive insect pest in forests, including diversifying crop rotations, altering the timing of planting, tillage and irrigation, using less sensitive crops in infested areas, applying biological control agents, and turning to alternative reduced risk insecticides. Continued research into alternatives is warranted, but equally pressing is the need for information transfer and training for farmers and pest managers and the need for policies and regulations to encourage the adoption of IPM strategies and their alternative pest control options.

Tea saponin reduces the damage of Ectropis obliqua to tea crops, and exerts reduced effects on the spiders Ebrechtella tricuspidata and Evarcha albaria compared to chemical insecticides

Directory of Open Access Journals (Sweden)

Chi Zeng

2018-03-01

Full Text Available Background Tea is one of the most economically important crops in China. However, the tea geometrid (Ectropis obliqua, a serious leaf-feeding pest, causes significant damage to tea crops and reduces tea yield and quality. Spiders are the most dominant predatory enemies in the tea plantation ecosystem, which makes them potentially useful biological control agents of E. obliqua. These highlight the need for alternative pest control measures. Our previous studies have shown that tea saponin (TS exerts insecticidal activity against lepidopteran pests. Here, we investigate whether TS represents a potentially new alternative insecticide with no harm to spiders. Methods We investigated laboratory bioactivities and the field control properties of TS solution against E. obliqua. (i A leaf-dip bioassay was used to evaluate the toxicity of TS to 3rd-instar E. obliqua larvae and effects of TS on the activities of enzymes glutathione-S-transferase (GST, acetylcholinesterase (AChE, carboxylesterase (CES and peroxidase (POD of 3rd-instar E. obliqua larvae in the laboratory. (ii Topical application was used to measure the toxicity of 30% TS (w/v and two chemical insecticides (10% bifenthrin EC and 50% diafenthiuron SC to two species of spider, Ebrechtella tricuspidata and Evarcha albaria. (iii Field trials were used to investigate the controlling efficacy of 30% TS against E. obliqua larvae and to classify the effect of TS to spiders in the tea plantation. Results The toxicity of TS to 3rd-instar E. obliqua larvae occurred in a dose-dependent manner and the LC50 was 164.32 mg/mL. Activities of the detoxifying-related enzymes, GST and POD, increased in 3rd-instar E. obliqua larvae, whereas AChE and CES were inhibited with time by treatment with TS. Mortalities of E. tricuspidata and E. albaria after 48 h with 30% TS treatment (16.67% and 20%, respectively were significantly lower than those with 10% bifenthrin EC (80% and 73.33%, respectively and 50

The genome of cultivated sweet potato contains Agrobacterium T-DNAs with expressed genes: An example of a naturally transgenic food crop.

Science.gov (United States)

Kyndt, Tina; Quispe, Dora; Zhai, Hong; Jarret, Robert; Ghislain, Marc; Liu, Qingchang; Gheysen, Godelieve; Kreuze, Jan F

2015-05-05

Agrobacterium rhizogenes and Agrobacterium tumefaciens are plant pathogenic bacteria capable of transferring DNA fragments [transfer DNA (T-DNA)] bearing functional genes into the host plant genome. This naturally occurring mechanism has been adapted by plant biotechnologists to develop genetically modified crops that today are grown on more than 10% of the world's arable land, although their use can result in considerable controversy. While assembling small interfering RNAs, or siRNAs, of sweet potato plants for metagenomic analysis, sequences homologous to T-DNA sequences from Agrobacterium spp. were discovered. Simple and quantitative PCR, Southern blotting, genome walking, and bacterial artificial chromosome library screening and sequencing unambiguously demonstrated that two different T-DNA regions (IbT-DNA1 and IbT-DNA2) are present in the cultivated sweet potato (Ipomoea batatas [L.] Lam.) genome and that these foreign genes are expressed at detectable levels in different tissues of the sweet potato plant. IbT-DNA1 was found to contain four open reading frames (ORFs) homologous to the tryptophan-2-monooxygenase (iaaM), indole-3-acetamide hydrolase (iaaH), C-protein (C-prot), and agrocinopine synthase (Acs) genes of Agrobacterium spp. IbT-DNA1 was detected in all 291 cultigens examined, but not in close wild relatives. IbT-DNA2 contained at least five ORFs with significant homology to the ORF14, ORF17n, rooting locus (Rol)B/RolC, ORF13, and ORF18/ORF17n genes of A. rhizogenes. IbT-DNA2 was detected in 45 of 217 genotypes that included both cultivated and wild species. Our finding, that sweet potato is naturally transgenic while being a widely and traditionally consumed food crop, could affect the current consumer distrust of the safety of transgenic food crops.

Pollen Sterility—A Promising Approach to Gene Confinement and Breeding for Genetically Modified Bioenergy Crops

Directory of Open Access Journals (Sweden)

Albert P. Kausch

2012-10-01

Full Text Available Advanced genetic and biotechnology tools will be required to realize the full potential of food and bioenergy crops. Given current regulatory concerns, many transgenic traits might never be deregulated for commercial release without a robust gene confinement strategy in place. The potential for transgene flow from genetically modified (GM crops is widely known. Pollen-mediated transfer is a major component of gene flow in flowering plants and therefore a potential avenue for the escape of transgenes from GM crops. One approach for preventing and/or mitigating transgene flow is the production of trait linked pollen sterility. To evaluate the feasibility of generating pollen sterility lines for gene confinement and breeding purposes we tested the utility of a promoter (Zm13Pro from a maize pollen-specific gene (Zm13 for driving expression of the reporter gene GUS and the cytotoxic gene barnase in transgenic rice (Oryza sativa ssp. Japonica cv. Nipponbare as a monocot proxy for bioenergy grasses. This study demonstrates that the Zm13 promoter can drive pollen-specific expression in stably transformed rice and may be useful for gametophytic transgene confinement and breeding strategies by pollen sterility in food and bioenergy crops.

Insecticide assays against the brown stink bug feeding on pecan

Science.gov (United States)

The brown stink bug, Euschistus servus (Say) (Hemiptera: Pentatomidae), is an economic pest of pecan, Carya illinoinensis (Wangenh) K. Koch (Juglandaceae), and other agronomic crops across the southeastern U.S. Management of this pest is mainly via insecticides. Many commercial products indicate o...

Susceptibility of natural enemies of pests of agriculture to commonly applied insecticides in Honduras

International Nuclear Information System (INIS)

Bustamante, M.; Sabillon, A.; Velasquez, C.; Ordonez, J.; Baquedano, F.

1999-01-01

Insecticides are commonly used by Honduran farmers to control pest insects in agricultural crops such as corn, melons and tomatoes. However, the insecticides have the potential for toxicity to the natural enemies of the pest insects also. Therefore, efforts are being made to identify insecticides which, when used within the Inegerated Pest Management (IPM) programme, are selectively more toxic to the pest insects than their natural enemies. A number of selected chemical insecticides and a biological insecticide (NPV) were tested in three different tests to determine toxicity to two beneficial insects: Telenomus remus Nixon (Hymenoptera: Scelionidae) and Chrysoperla carnea Steph. (Neuroptera: Chrysopidae). All insecticides were toxic to T. remus which suffered high mortality. There was no significant difference in mortality of the insect due to the method of exposure to the insecticides. There were some differences in the toxicity of the insecticides to C. carnea, and abamectin, bifenthrin, cypermethrin, diafenthiuron, imidacloprid and fenpropathrin were relatively less toxic and could be used in IPM for the control of pest insects. (author)

Transgenic rice plants harboring an introduced potato proteinase inhibitor II gene are insect resistant.

Science.gov (United States)

Duan, X; Li, X; Xue, Q; Abo-el-Saad, M; Xu, D; Wu, R

1996-04-01

We introduced the potato proteinase inhibitor II (PINII) gene (pin2) into several Japonica rice varieties, and regenerated a large number of transgenic rice plants. Wound-inducible expression of the pin2 gene driven by its own promoter, together with the first intron of the rice actin 1 gene (act1), resulted in high-level accumulation of the PINII protein in the transgenic plants. The introduced pin2 gene was stably inherited in the second, third, and fourth generations, as shown by molecular analyses. Based on data from the molecular analyses, several homozygous transgenic lines were obtained. Bioassay for insect resistance with the fifth-generation transgenic rice plants showed that transgenic rice plants had increased resistance to a major rice insect pest, pink stem borer (Sesamia inferens). Thus, introduction of an insecticidal proteinase inhibitor gene into cereal plants can be used as a general strategy for control of insect pests.

Regulatory challenges for GM crops in developing economies: the African experience.

Science.gov (United States)

Nang'ayo, Francis; Simiyu-Wafukho, Stella; Oikeh, Sylvester O

2014-12-01

Globally, transgenic or genetically modified (GM) crops are considered regulated products that are subject to regulatory oversight during trans-boundary movement, testing and environmental release. In Africa, regulations for transgenic crops are based on the outcomes of the historic Earth Summit Conference held in Rio, Brazil two decades ago, namely, the adoption of the Convention on Biological Diversity (CBD) and the subsequent adoption of the Cartagena Protocol on Biosafety. To exploit the potential benefits of transgenic crops while safeguarding the potential risks on human health and environment, most African countries have signed and ratified the CBD and the Cartagena Protocol on Biosafety. Consequently, these countries are required to take appropriate legal, administrative and other measures to ensure that the handling and utilization of living modified organisms are undertaken in a manner that reduces the risks to humans and the environment. These countries are also expected to provide regulatory oversight on transgenic crops through functional national biosafety frameworks (NBFs). While in principle this approach is ideal, NBFs in most African countries are steeped in a host of policy, legal and operational challenges that appear to be at cross-purposes with the noble efforts of seeking to access, test and deliver promising GM crops for use by resource-limited farmers in Africa. In this paper we discuss the regulatory challenges faced during the development and commercialization of GM crops based on experiences from countries in Sub-Saharan Africa.

Insecticide resistance in the western flower thrips, Frankliniella occidentalis

DEFF Research Database (Denmark)

Jensen, Sten Erik

of acetylcholinesterase, the target site enzyme for methiocarb. The results from bioassays with synergists included indicated involvement of cytochrome P450- monooxygenases and esterases in methiocarb resistance in the most resistant populations. Selection with methiocarb on one of the populations to increase the level......The western flower thrips, Frankliniella occidentalis (Pergande) is a serious pest on a wide range of crops throughout the world. In Denmark F. occidentalis is a pest in greenhouses. F. occidentalis is difficult to control with insecticides because of its thigmokinetic behaviour and resistance...... to insecticides. Since F. occidentulis spread to become a worldwide pest in 1980’es, resistance to a number of different insecticides has been shown in many populations of F. occidentalis. This flower thrips has the potential of fast development of resistance owing to the short generation time, high fecundity...

Transgenic Strategies for Enhancement of Nematode Resistance in Plants

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Muhammad A. Ali

2017-05-01

Full Text Available Plant parasitic nematodes (PPNs are obligate biotrophic parasites causing serious damage and reduction in crop yields. Several economically important genera parasitize various crop plants. The root-knot, root lesion, and cyst nematodes are the three most economically damaging genera of PPNs on crops within the family Heteroderidae. It is very important to devise various management strategies against PPNs in economically important crop plants. Genetic engineering has proven a promising tool for the development of biotic and abiotic stress tolerance in crop plants. Additionally, the genetic engineering leading to transgenic plants harboring nematode resistance genes has demonstrated its significance in the field of plant nematology. Here, we have discussed the use of genetic engineering for the development of nematode resistance in plants. This review article also provides a detailed account of transgenic strategies for the resistance against PPNs. The strategies include natural resistance genes, cloning of proteinase inhibitor coding genes, anti-nematodal proteins and use of RNA interference to suppress nematode effectors. Furthermore, the manipulation of expression levels of genes induced and suppressed by nematodes has also been suggested as an innovative approach for inducing nematode resistance in plants. The information in this article will provide an array of possibilities to engineer resistance against PPNs in different crop plants.

Arthropod Pest Control for UK Oilseed Rape - Comparing Insecticide Efficacies, Side Effects and Alternatives.

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Han Zhang

Full Text Available Oilseed rape (Brassica napus is an important combinable break crop in the UK, which is largely protected from arthropod pests by insecticidal chemicals. Despite ongoing debate regarding the use of neonicotinoids, the dominant seed treatment ingredients used for this crop, there is little publicly available data comparing the efficacy of insecticides in controlling key arthropod pests or comparing the impacts on non-target species and the wider environment. To provide an insight into these matters, a UK-wide expert survey targeting agronomists and entomologists was conducted from March to June 2015. Based on the opinions of 90 respondents, an average of 20% yield loss caused by the key arthropod pests was expected to have occurred in the absence of insecticide treatments. Relatively older chemical groups were perceived to have lower efficacy for target pests than newer ones, partly due to the development of insecticide resistance. Without neonicotinoid seed treatments, a lack of good control for cabbage stem flea beetle was perceived. Wide spectrum foliar insecticide sprays were perceived to have significantly greater negative impacts than seed treatments on users' health, natural enemies, pollinators, soil and water, and many foliar active ingredients have had potential risks for non-target arthropod species in UK oilseed rape fields for the past 25 years. Overall, 72% of respondents opposed the neonicotinoid restriction, while 10% supported it. Opposition and support of the restriction were largely based on concerns for pollinators and the wider environment, highlighting the uncertainty over the side effects of neonicotinoid use. More people from the government and research institutes leaned towards neutrality over the issue, compared to those directly involved in growing the crop. Neonicotinoid restriction was expected to result in greater effort and expenditure on pest control and lower production (0-1 t/ha less. Alternatives for future

Glycinebetaine synthesizing transgenic potato plants exhibit enhanced tolerance to salt and cold stresses

International Nuclear Information System (INIS)

Ahmad, R.; Hussain, J.

2014-01-01

Abiotic stresses are the most important contributors towards low productivity of major food crops. Various attempts have been made to enhance abiotic stress tolerance of crop plants by classical breeding and genetic transformation. Genetic transformation with glycinebetaine (GB) synthesizing enzymes' gene(s) in naturally non accumulating plants has resulted in enhanced tolerance against variety of abiotic stresses. Present study was aimed to evaluate the performance of GB synthesizing transgenic potato plants against salt and cold stresses. Transgenic potato plants were challenged against salt and cold stresses at whole plant level. Transgenic lines were characterized to determine the transgene copy number. Different parameters like integrity, chlorophyll contents, tuber yield and vegetative biomass were studied to monitor the stress tolerance of transgenic potato plants. The results were compared with Non-transgenic (NT) plants and statistically analyzed to evaluate significant differences. Multi-copy insertion of expression cassette was found in both transgenic lines. Upon salt stress, transgenic plants maintained better growth as compared to NT plants. The tuber yield of transgenic plants was significantly greater than NT plants in salt stress. Transgenic plants showed improved membrane integrity against cold stress by depicting appreciably reduced ion leakage as compared to NT plants. Moreover, transgenic plants showed significantly less chlorophyll bleaching than NT plants upon cold stress. In addition, NT plants accumulated significantly less biomass, and yielded fewer tubers as compared to transgenic plants after cold stress treatment. The study will be a committed step for field evaluation of transgenic plants with the aim of commercialization. (author)

MS-based analytical methodologies to characterize genetically modified crops.

Science.gov (United States)

García-Cañas, Virginia; Simó, Carolina; León, Carlos; Ibáñez, Elena; Cifuentes, Alejandro

2011-01-01

The development of genetically modified crops has had a great impact on the agriculture and food industries. However, the development of any genetically modified organism (GMO) requires the application of analytical procedures to confirm the equivalence of the GMO compared to its isogenic non-transgenic counterpart. Moreover, the use of GMOs in foods and agriculture faces numerous criticisms from consumers and ecological organizations that have led some countries to regulate their production, growth, and commercialization. These regulations have brought about the need of new and more powerful analytical methods to face the complexity of this topic. In this regard, MS-based technologies are increasingly used for GMOs analysis to provide very useful information on GMO composition (e.g., metabolites, proteins). This review focuses on the MS-based analytical methodologies used to characterize genetically modified crops (also called transgenic crops). First, an overview on genetically modified crops development is provided, together with the main difficulties of their analysis. Next, the different MS-based analytical approaches applied to characterize GM crops are critically discussed, and include "-omics" approaches and target-based approaches. These methodologies allow the study of intended and unintended effects that result from the genetic transformation. This information is considered to be essential to corroborate (or not) the equivalence of the GM crop with its isogenic non-transgenic counterpart. Copyright © 2010 Wiley Periodicals, Inc.

Availability and utility of crop composition data.

Science.gov (United States)

Kitta, Kazumi

2013-09-04

The safety assessment of genetically modified (GM) crops is mandatory in many countries. Although the most important factor to take into account in these safety assessments is the primary effects of artificially introduced transgene-derived traits, possible unintended effects attributed to the insertion of transgenes must be carefully examined in parallel. However, foods are complex mixtures of compounds characterized by wide variations in composition and nutritional values. Food components are significantly affected by various factors such as cultivars and the cultivation environment including storage conditions after harvest, and it can thus be very difficult to detect potential adverse effects caused by the introduction of a transgene. A comparative approach focusing on the identification of differences between GM foods and their conventional counterparts has been performed to reveal potential safety issues and is considered the most appropriate strategy for the safety assessment of GM foods. This concept is widely shared by authorities in many countries. For the efficient safety assessment of GM crops, an easily accessible and wide-ranging compilation of crop composition data is required for use by researchers and regulatory agencies. Thus, we developed an Internet-accessible food composition database comprising key nutrients, antinutrients, endogenous toxicants, and physiologically active substances of staple crops such as rice and soybeans. The International Life Sciences Institute has also been addressing the same matter and has provided the public a crop composition database of soybeans, maize, and cotton.

Transgenic plants: from first successes to future applications.

Science.gov (United States)

Van Lijsebettens, Mieke; Angenon, Geert; De Block, Marc

2013-01-01

This dialogue was held between the Guest Editors of the Special Issue on "Plant Transgenesis" of the Int. J. Dev. Biol. and Marc De Block. He was one of the first scientists worldwide to obtain transgenic plants transformed with the chimeric selectable marker genes encoding neomycin phosphotransferase and bialaphos that confer resistance against the antibiotic kanamycin and the herbicide Basta®/glufosinate, respectively at the Department of Genetics of Ghent University and, later on, at the spin-off company, Plant Genetic Systems. Today, these two genes are still the most frequently utilized markers in transgene technology. Marc De Block chose to work on the improvement of crops in an industrial environment to help realize the production of superior seeds or products. He was part of the team that developed the male sterility/restorer system in canola (Brassica napus var. napus) that led to the first hybrid lines to be commercialized as successful products of transgene technology. In more than 30 years of research, he developed transformation procedures for numerous crops, designed histochemical, biochemical and physiological assays to monitor plant performance, and made original and innovative contributions to plant biology. Presently, he considers transgenic research part of the toolbox for plant improvement and essential for basic plant research.

Molecular Characterization of Transgenic Events Using Next Generation Sequencing Approach.

Science.gov (United States)

Guttikonda, Satish K; Marri, Pradeep; Mammadov, Jafar; Ye, Liang; Soe, Khaing; Richey, Kimberly; Cruse, James; Zhuang, Meibao; Gao, Zhifang; Evans, Clive; Rounsley, Steve; Kumpatla, Siva P

2016-01-01

Demand for the commercial use of genetically modified (GM) crops has been increasing in light of the projected growth of world population to nine billion by 2050. A prerequisite of paramount importance for regulatory submissions is the rigorous safety assessment of GM crops. One of the components of safety assessment is molecular characterization at DNA level which helps to determine the copy number, integrity and stability of a transgene; characterize the integration site within a host genome; and confirm the absence of vector DNA. Historically, molecular characterization has been carried out using Southern blot analysis coupled with Sanger sequencing. While this is a robust approach to characterize the transgenic crops, it is both time- and resource-consuming. The emergence of next-generation sequencing (NGS) technologies has provided highly sensitive and cost- and labor-effective alternative for molecular characterization compared to traditional Southern blot analysis. Herein, we have demonstrated the successful application of both whole genome sequencing and target capture sequencing approaches for the characterization of single and stacked transgenic events and compared the results and inferences with traditional method with respect to key criteria required for regulatory submissions.

Molecular Characterization of Transgenic Events Using Next Generation Sequencing Approach.

Directory of Open Access Journals (Sweden)

Satish K Guttikonda

Full Text Available Demand for the commercial use of genetically modified (GM crops has been increasing in light of the projected growth of world population to nine billion by 2050. A prerequisite of paramount importance for regulatory submissions is the rigorous safety assessment of GM crops. One of the components of safety assessment is molecular characterization at DNA level which helps to determine the copy number, integrity and stability of a transgene; characterize the integration site within a host genome; and confirm the absence of vector DNA. Historically, molecular characterization has been carried out using Southern blot analysis coupled with Sanger sequencing. While this is a robust approach to characterize the transgenic crops, it is both time- and resource-consuming. The emergence of next-generation sequencing (NGS technologies has provided highly sensitive and cost- and labor-effective alternative for molecular characterization compared to traditional Southern blot analysis. Herein, we have demonstrated the successful application of both whole genome sequencing and target capture sequencing approaches for the characterization of single and stacked transgenic events and compared the results and inferences with traditional method with respect to key criteria required for regulatory submissions.

A future scenario of the global regulatory landscape regarding genome-edited crops

Science.gov (United States)

Araki, Motoko

2017-01-01

ABSTRACT The global agricultural landscape regarding the commercial cultivation of genetically modified (GM) crops is mosaic. Meanwhile, a new plant breeding technique, genome editing is expected to make genetic engineering-mediated crop breeding more socially acceptable because it can be used to develop crop varieties without introducing transgenes, which have hampered the regulatory review and public acceptance of GM crops. The present study revealed that product- and process-based concepts have been implemented to regulate GM crops in 30 countries. Moreover, this study analyzed the regulatory responses to genome-edited crops in the USA, Argentina, Sweden and New Zealand. The findings suggested that countries will likely be divided in their policies on genome-edited crops: Some will deregulate transgene-free crops, while others will regulate all types of crops that have been modified by genome editing. These implications are discussed from the viewpoint of public acceptance. PMID:27960622

Expression of a Chimeric Gene Encoding Insecticidal Crystal Protein Cry1Aabc of Bacillus thuringiensis in Chickpea (Cicer arietinum L.) Confers Resistance to Gram Pod Borer (Helicoverpa armigera Hubner.).

Science.gov (United States)

Das, Alok; Datta, Subhojit; Thakur, Shallu; Shukla, Alok; Ansari, Jamal; Sujayanand, G K; Chaturvedi, Sushil K; Kumar, P A; Singh, N P

2017-01-01

Domain swapping and generation of chimeric insecticidal crystal protein is an emerging area of insect pest management. The lepidopteran insect pest, gram pod borer ( Helicoverpa armigera H.) wreaks havoc to chickpea crop affecting production. Lepidopteran insects were reported to be controlled by Bt ( cryI ) genes. We designed a plant codon optimized chimeric Bt gene ( cry1Aabc ) using three domains from three different cry1A genes (domains I, II, and III from cry1Aa , cry1Ab , and cry1Ac , respectively) and expressed it under the control of a constitutive promoter in chickpea ( cv . DCP92-3) to assess its effect on gram pod borer. A total of six transgenic chickpea shoots were established by grafting into mature fertile plants. The in vitro regenerated (organogenetic) shoots were selected based on antibiotic kanamycin monosulfate (100 mg/L) with transformation efficiency of 0.076%. Three transgenic events were extensively studied based on gene expression pattern and insect mortality across generations. Protein expression in pod walls, immature seeds and leaves (pre- and post-flowering) were estimated and expression in pre-flowering stage was found higher than that of post-flowering. Analysis for the stable integration, expression and insect mortality (detached leaf and whole plant bioassay) led to identification of efficacious transgenic chickpea lines. The chimeric cry1Aabc expressed in chickpea is effective against gram pod borer and generated events can be utilized in transgenic breeding program.

Expression of a Chimeric Gene Encoding Insecticidal Crystal Protein Cry1Aabc of Bacillus thuringiensis in Chickpea (Cicer arietinum L. Confers Resistance to Gram Pod Borer (Helicoverpa armigera Hubner.

Directory of Open Access Journals (Sweden)

Alok Das

2017-08-01

Full Text Available Domain swapping and generation of chimeric insecticidal crystal protein is an emerging area of insect pest management. The lepidopteran insect pest, gram pod borer (Helicoverpa armigera H. wreaks havoc to chickpea crop affecting production. Lepidopteran insects were reported to be controlled by Bt (cryI genes. We designed a plant codon optimized chimeric Bt gene (cry1Aabc using three domains from three different cry1A genes (domains I, II, and III from cry1Aa, cry1Ab, and cry1Ac, respectively and expressed it under the control of a constitutive promoter in chickpea (cv. DCP92-3 to assess its effect on gram pod borer. A total of six transgenic chickpea shoots were established by grafting into mature fertile plants. The in vitro regenerated (organogenetic shoots were selected based on antibiotic kanamycin monosulfate (100 mg/L with transformation efficiency of 0.076%. Three transgenic events were extensively studied based on gene expression pattern and insect mortality across generations. Protein expression in pod walls, immature seeds and leaves (pre- and post-flowering were estimated and expression in pre-flowering stage was found higher than that of post-flowering. Analysis for the stable integration, expression and insect mortality (detached leaf and whole plant bioassay led to identification of efficacious transgenic chickpea lines. The chimeric cry1Aabc expressed in chickpea is effective against gram pod borer and generated events can be utilized in transgenic breeding program.

Effect of repeated pesticide applications on soil properties in cotton fields: II. Insecticide residues and impact on dehydrogenase and arginine deaminase activities

International Nuclear Information System (INIS)

Vig, K.; Singh, D.K.; Agarwal, H.C.; Dhawan, A.K.; Dureja, P.

2001-01-01

Insecticides were applied sequentially at recommended dosages post crop emergence in cotton fields and soil was sampled at regular intervals after each treatment. Soil was analysed for insecticide residues and activity of the enzymes dehydrogenase and arginine deaminase. Insecticide residues detected in the soil were in small quantities and they did not persist for long. Only endosulfan leached below 15 cm. Insecticides had only temporary effects on enzyme activities which disappeared either before the next insecticide treatment or by the end of the experimental period. (author)

Soil microflora and enzyme activities in rhizosphere of Transgenic Bt cotton hybrid under different intercropping systems and plant protection schedules

Science.gov (United States)

Biradar, D. P.; Alagawadi, A. R.; Basavanneppa, M. A.; Udikeri, S. S.

2012-04-01

Field experiments were conducted over three rainy seasons of 2005-06 to 2007-08 on a Vertisol at Dharwad, Karnataka, India to study the effect of intercropping and plant protection schedules on productivity, soil microflora and enzyme activities in the rhizosphere of transgenic Bt cotton hybrid. The experiment consisted of four intercropping systems namely, Bt cotton + okra, Bt cotton + chilli, Bt cotton + onion + chilli and Bt cotton + redgram with four plant protection schedules (zero protection, protection for Bt cotton, protection for intercrop and protection for both crops). Observations on microbial populations and enzyme activities were recorded at 45, 90, 135 and 185 (at harvest) days after sowing (DAS). Averaged over years, Bt cotton + okra intercropping had significantly higher total productivity than Bt cotton + chilli and Bt cotton + redgram intercropping system and was similar to Bt cotton + chilli + onion intercropping system. With respect to plant protection schedules for bollworms, protection for both cotton and intercrops recorded significantly higher yield than the rest of the treatments. Population of total bacteria, fungi, actinomycetes, P-solubilizers, free-living N2 fixers as well as urease, phosphatase and dehydrogenase enzyme activities increased up to 135 days of crop growth followed by a decline. Among the intercropping systems, Bt cotton + chilli recorded significantly higher population of microorganisms and enzyme activities than other cropping systems. While Bt cotton with okra as intercrop recorded the least population of total bacteria and free-living N2 fixers as well as urease activity. Intercropping with redgram resulted in the least population of actinomycetes, fungi and P-solubilizers, whereas Bt cotton with chilli and onion recorded least activities of dehydrogenase and phosphatase. Among the plant protection schedules, zero protection recorded maximum population of microorganisms and enzyme activities. This was followed by the

Responsive Polymers for Crop Protection

Directory of Open Access Journals (Sweden)

Serban F. Peteu

2010-08-01

Full Text Available This review outlines the responsive polymer methods currently in use with their potential application to plant protection and puts forward plant-specific mechanisms as stimuli in newly devised methods for smart release of crop protection agents (CPAs. CPAs include chemicals (fungicides, insecticides, herbicides, biochemicals (antibiotics, RNA-based vaccines for plant viruses, semiochemicals (pheromones, repellents, allomones, microbial pesticides, growth regulators (insect and plant or micronutrients, all with crop protection effects. This appraisal focuses on emerging uses of polymer nano-encapsulated CPAs. Firstly, the most interesting advances in controlled release methods are critically discussed with their advantages and drawbacks. Secondly, several plant-specific stimuli-based smart methods are anticipated for use alongside the polymer nano- or micro-capsules. These new CPA release methods are designed to (i protect plants against infection produced by fungi or bacteria, and (ii apply micro-nutrients when the plants need it the most. Thus, we foresee (i the responsive release of nano- encapsulated bio-insecticides regulated by plant stress enzymes, and (ii the delivery of micro-nutrients synchronized by the nature or intensity of plant root exudates. Such continued advances of nano-scale smart polymer-based CPAs for the protection of crops herald a “small revolution” for the benefit of sustainable agriculture.

Insecticide use in hybrid onion seed production affects pre- and postpollination processes.

Science.gov (United States)

Gillespie, Sandra; Long, Rachael; Seitz, Nicola; Williams, Neal

2014-02-01

Research on threats to pollination service in agro-ecosystems has focused primarily on the negative impacts of land use change and agricultural practices such as insecticide use on pollinator populations. Insecticide use could also affect the pollination process, through nonlethal impacts on pollinator attraction and postpollination processes such as pollen viability or pollen tube growth. Hybrid onion seed (Allium cepa L., Alliaceae) is an important pollinator-dependent crop that has suffered yield declines in California, concurrent with increased insecticide use. Field studies suggest that insecticide use reduces pollination service in this system. We conducted a field experiment manipulating insecticide use to examine the impacts of insecticides on 1) pollinator attraction, 2) pollen/stigma interactions, and 3) seed set and seed quality. Select insecticides had negative impacts on pollinator attraction and pollen/stigma interactions, with certain products dramatically reducing pollen germination and pollen tube growth. Decreased pollen germination was not associated with reduced seed set; however, reduced pollinator attraction was associated with lower seed set and seed quality, for one of the two female lines examined. Our results highlight the importance of pesticide effects on the pollination process. Overuse may lead to yield reductions through impacts on pollinator behavior and postpollination processes. Overall, in hybrid onion seed production, moderation in insecticide use is advised when controlling onion thrips, Thrips tabaci, on commercial fields.

Glyphosate Effects on Plant Mineral Nutrition, Crop Rhizosphere Microbiota, and Plant Disease in Glyphosate-Resistant Crops

Science.gov (United States)

2012-01-01

Claims have been made recently that glyphosate-resistant (GR) crops sometimes have mineral deficiencies and increased plant disease. This review evaluates the literature that is germane to these claims. Our conclusions are: (1) although there is conflicting literature on the effects of glyphosate on mineral nutrition on GR crops, most of the literature indicates that mineral nutrition in GR crops is not affected by either the GR trait or by application of glyphosate; (2) most of the available data support the view that neither the GR transgenes nor glyphosate use in GR crops increases crop disease; and (3) yield data on GR crops do not support the hypotheses that there are substantive mineral nutrition or disease problems that are specific to GR crops. PMID:23013354

Type 'A' and 'B' recovery revisited: The role of field-edge habitats for Collembola and macroarthropod community recovery after insecticide treatment

International Nuclear Information System (INIS)

Frampton, Geoff K.; Gould, Philip J.L.; Brink, Paul J. van den; Hendy, Eleanor

2007-01-01

Previous work has identified two patterns of arthropod recovery after insecticide applications to arable crops: dispersal-mediated recolonisation from untreated areas (Type A) and recolonisation within treated areas assisted by reduced predation (Type B). In this study, connectivity between field-edge habitats was manipulated using barriers to investigate whether a crop edge and adjacent hedgerow influence recolonisation of an insecticide-treated crop by surface-active Collembola and other arthropods. Collembola recovery patterns differed among closely-related taxa. Epigeic collembolan and macroarthropod communities were more diverse and abundant, and rates of artificial prey predation were higher, in sprayed crop areas connected to both hedgerow and unsprayed crop edge than in sprayed areas connected to the unsprayed edge alone. These findings indicate that effectiveness of unsprayed crop edges as sources of field recolonisation may depend on adjoining field margin habitats. An assumption in risk assessment that unsprayed crop edges assist population recovery within treated areas is not supported. - Collembola recolonisation differs among species; effectiveness of unsprayed crop edges as sources of arthropod recolonisation may depend on adjacent habitat

Efficient transformation and regeneration of transgenic cassava using the neomycin phosphotransferase gene as aminoglycoside resistance marker gene.

Science.gov (United States)

Niklaus, Michael; Gruissem, Wilhelm; Vanderschuren, Hervé

2011-01-01

Cassava is one of the most important crops in the tropics. Its industrial use for starch and biofuel production is also increasing its importance for agricultural production in tropical countries. In the last decade cassava biotechnology has emerged as a valuable alternative to the breeding constraints of this highly heterozygous crop for improved trait development of cassava germplasm. Cassava transformation remains difficult and time-consuming because of limitations in selecting transgenic tissues and regeneration of transgenic plantlets. We have recently reported an efficient and robust cassava transformation protocol using the hygromycin phosphotransferase II (hptII) gene as selection marker and the aminoglycoside hygromycin at optimal concentrations to maximize the regeneration of transgenic plantlets. In the present work, we expanded the transformation protocol to the use of the neomycin phosphotransferase II (nptII) gene as selection marker. Several aminoglycosides compatible with the use of nptII were tested and optimal concentrations for cassava transformation were determined. Given its efficiency equivalent to hptII as selection marker with the described protocol, the use of nptII opens new possibilities to engineer transgenic cassava lines with multiple T-DNA insertions and to produce transgenic cassava with a resistance marker gene that is already deregulated in several commercial transgenic crops.

Toxicity of Pesticide Tank Mixtures from Rice Crops Against Telenomus podisi Ashmead (Hymenoptera: Platygastridae).

Science.gov (United States)

de B Pazini, J; Pasini, R A; Rakes, M; de Armas, F S; Seidel, E J; da S Martins, J F; Grützmacher, A D

2017-08-01

The use of insecticides, herbicides, and fungicides commonly occurs in mixtures in tanks in order to control phytosanitary problems in crops. However, there is no information regarding the effects of these mixtures on non-target organisms associated to the rice agroecosystem. The aim of this study was to know the toxicity of pesticide tank mixtures from rice crops against Telenomus podisi Ashmead (Hymenoptera: Platygastridae). Based on the methods adapted from the International Organisation for Biological and Integrated Control of Noxious Animals and Plants (IOBC), adults of T. podisi were exposed to residues of insecticides, herbicides, and fungicides, individually or in mixture commonly used by growers, in laboratory and on rice plants in a greenhouse. The mixture between fungicides tebuconazole, triclyclazole, and azoxystrobin and the mixture between herbicides cyhalofop-butyl, imazethapyr, imazapyr/imazapic, and penoxsulam are harmless to T. podisi and can be used in irrigated rice crops without harming the natural biological control. The insecticides cypermethin, thiamethoxam, and bifenthrin/carbosulfan increase the toxicity of the mixtures in tank with herbicides and fungicides, being more toxic to T. podisi and less preferred for use in phytosanitary treatments in the rice crop protection.

Bt rice harbouring cry genes controlled by a constitutive or wound-inducible promoter: protection and transgene expression under Mediterranean field conditions.

Science.gov (United States)

Breitler, Jean Christophe; Vassal, Jean Michel; del Mar Catala, Maria; Meynard, Donaldo; Marfà, Victoria; Melé, Enric; Royer, Monique; Murillo, Isabel; San Segundo, Blanca; Guiderdoni, Emmanuel; Messeguer, Joaquima

2004-09-01

Seven homozygous transgenic lines of two European commercial cultivars of rice (Ariete (A) and Senia (S)), harbouring the cry1B or cry1Aa Bacillus thuringiensis (Bt) delta-endotoxin genes, were field evaluated for protection from striped stem borer (SSB) (Chilo suppressalis) damage during the 2001 and 2002 summer crop seasons in the Delta de l'Ebre region, Spain. The plant codon-optimized toxin gene was placed under the control of the promoter of either the constitutive ubi1 gene or the wound-inducible mpi gene from maize. Stable, high-level, insecticidal protein accumulation was observed throughout root, leaf and seed tissues of field-grown plants harbouring the cry1B (lines A64.1, A33.1, A3.4 and S98.9) or cry1Aa (lines S05.1 and A19.14) genes under the control of the ubi1 promoter. Conversely, no toxin was detected in unwounded vegetative tissues of the A9.1 line harbouring the cry1B gene controlled by the mpi promoter, indicating that natural environmental stresses did not trigger the activity of the wound-inducible promoter. However, the toxin accumulated at 0.2% total soluble proteins in A9.1 sheath tissue exhibiting brown lesions resulting from SSB damage. The agronomical traits and performance of the transgenic lines were generally comparable with parental controls, except in the two lines accumulating Cry1Aa, which exhibited a high frequency of plants non-true to type. Natural infestation was assisted with manual infestations of L2/L3 SSB larvae in border control plants surrounding the experimental plots, which served as a reservoir for the second-cycle SSB population. The observation of damage (brown lesions and dead hearts) during the crop season and dissection of plants at harvest stage revealed a range of protection amongst the transgenic lines, which was highly consistent with the level of toxin accumulation and with previous experience in greenhouse assays. Lines A3.4 and S05.1 were found to exhibit stable and full protection against SSB attacks

Blended Refuge and Insect Resistance Management for Insecticidal Corn

Science.gov (United States)

Crespo, Andre L B; Pan, Zaiqi; Crain, Philip R; Thompson, Stephen D; Pilcher, Clinton D; Sethi, Amit

2018-01-01

Abstract In this review, we evaluate the intentional mixing or blending of insecticidal seed with refuge seed for managing resistance by insects to insecticidal corn (Zea mays). We first describe the pest biology and farming practices that will contribute to weighing trade-offs between using block refuges and blended refuges. Case studies are presented to demonstrate how the trade-offs will differ in different systems. We compare biological aspects of several abstract models to guide the reader through the history of modeling, which has played a key role in the promotion or denigration of blending in various scientific debates about insect resistance management for insecticidal crops. We conclude that the use of blended refuge should be considered on a case-by-case basis after evaluation of insect biology, environment, and farmer behavior. For Diabrotica virgifera virgifera, Ostrinia nubilalis, and Helicoverpa zea in the United States, blended refuge provides similar, if not longer, delays in the evolution of resistance compared to separate block refuges. PMID:29220481

Expression, Delivery and Function of Insecticidal Proteins Expressed by Recombinant Baculoviruses

Science.gov (United States)

Kroemer, Jeremy A.; Bonning, Bryony C.; Harrison, Robert L.

2015-01-01

Since the development of methods for inserting and expressing genes in baculoviruses, a line of research has focused on developing recombinant baculoviruses that express insecticidal peptides and proteins. These recombinant viruses have been engineered with the goal of improving their pesticidal potential by shortening the time required for infection to kill or incapacitate insect pests and reducing the quantity of crop damage as a consequence. A wide variety of neurotoxic peptides, proteins that regulate insect physiology, degradative enzymes, and other potentially insecticidal proteins have been evaluated for their capacity to reduce the survival time of baculovirus-infected lepidopteran host larvae. Researchers have investigated the factors involved in the efficient expression and delivery of baculovirus-encoded insecticidal peptides and proteins, with much effort dedicated to identifying ideal promoters for driving transcription and signal peptides that mediate secretion of the expressed target protein. Other factors, particularly translational efficiency of transcripts derived from recombinant insecticidal genes and post-translational folding and processing of insecticidal proteins, remain relatively unexplored. The discovery of RNA interference as a gene-specific regulation mechanism offers a new approach for improvement of baculovirus biopesticidal efficacy through genetic modification. PMID:25609310

Effectiveness of plant based insecticides as a sustainable means of ...

African Journals Online (AJOL)

Cucumber (Cucumis sativus) is an important crop in Pakistan. It is affected by many biotic and abiotic factors. Among these, Cucumber mosaic virus is the important disease with economic losses. The purpose of this study was to evaluate the effectiveness of plant based insecticides as a sustainable means to control the ...

Efficacy of some synthetic insecticides for control of cotton bollworms ...

African Journals Online (AJOL)

... and Betsulfan at 3.2 l ha-1 recorded the highest and lowest yields, respectively. For effective control of cotton bollworms for maximum yield in the ecology, Thionex applied at 2.8 l ha-1 is recommended. Keywords: Control, cotton bollworms, efficacy, Ghana, synthetic insecticides. African Crop Science Journal, Vol. 20, No.

The spatial impact of genetically modified crops

OpenAIRE

MUNRO, Alistair

2008-01-01

Although genetically modified (GM) organisms have attracted a great deal of public attention, analysis of their economic impacts has been less common. It is, perhaps, spatial externalities where the divergence between efficient and unregulated outcomes is potentially largest, because the presence of transgenic crops may eliminate or severely reduce the planting of organic varieties and other crops where some consumers have a preference for non-GM crops. This paper constructs a simple model of...

Bioactivity of flours of seeds of leguminous crops Pisum sativum ...

African Journals Online (AJOL)

Bioactivity of flours of seeds of leguminous crops Pisum sativum, Phaseolus vulgaris and Glycine max used as botanical insecticides against Sitophilus oryzae Linnaeus (Coleoptera: Curculionidae) on sorghum grains.

Potential transgenic routes to increase tree biomass.

Science.gov (United States)

Dubouzet, Joseph G; Strabala, Timothy J; Wagner, Armin

2013-11-01

Biomass is a prime target for genetic engineering in forestry because increased biomass yield will benefit most downstream applications such as timber, fiber, pulp, paper, and bioenergy production. Transgenesis can increase biomass by improving resource acquisition and product utilization and by enhancing competitive ability for solar energy, water, and mineral nutrients. Transgenes that affect juvenility, winter dormancy, and flowering have been shown to influence biomass as well. Transgenic approaches have increased yield potential by mitigating the adverse effects of prevailing stress factors in the environment. Simultaneous introduction of multiple genes for resistance to various stress factors into trees may help forest trees cope with multiple or changing environments. We propose multi-trait engineering for tree crops, simultaneously deploying multiple independent genes to address a set of genetically uncorrelated traits that are important for crop improvement. This strategy increases the probability of unpredictable (synergistic or detrimental) interactions that may substantially affect the overall phenotype and its long-term performance. The very limited ability to predict the physiological processes that may be impacted by such a strategy requires vigilance and care during implementation. Hence, we recommend close monitoring of the resultant transgenic genotypes in multi-year, multi-location field trials. Copyright © 2013 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Insecticides suppress natural enemies and increase pest damage in cabbage.

Science.gov (United States)

Bommarco, Riccardo; Miranda, Freddy; Bylund, Helena; Björkman, Christer

2011-06-01

, something that may be particularly relevant for the production of cash crops in tropical countries where insecticide use is heavy and possibly increasing.

Adventitious presence of transgenic events in the maize supply chain in Peru: A case study

NARCIS (Netherlands)

Santa-Maria, M.C.; Lajo-Morgan, G.; Guardia, L.

2014-01-01

Cultivation and trade of transgenic or genetically modified organisms (GMO) and commodities has become widespread worldwide. In particular, production of transgenic crops has seen an accelerated growth along with a complex regulatory process. Current Peruvian legislation prohibits import of

A point mutation (L1015F) of the voltage-sensitive sodium channel gene associated with lambda-cyhalothrin resistance in Apolygus lucorum (Meyer-Dür) population from the transgenic Bt cotton field of China.

Science.gov (United States)

Zhen, Congai; Gao, Xiwu

2016-02-01

In China, the green mirid bug, Apolygus lucorum (Meyer-Dür), has caused severe economic damage to many kinds of crops, especially the cotton and jujubes. Pyrethroid insecticides have been widely used for controlling this pest in the transgenic Bt cotton field. Five populations of A. lucorum collected from cotton crops at different locations in China were evaluated for lambda-cyhalothrin resistance. The results showed that only the population collected from Shandong Province exhibited 30-fold of resistance to lambda-cyhalothrin. Neither PBO nor DEF had obvious synergism when compared the synergistic ratio between SS and RR strain which was originated from the Shandong population. Besides, there were no statistically significant differences (p>0.05) in the carboxylesterase, glutathione S-transferase, or 7-ethoxycoumarin O-deethylase activities between the Shandong population and the laboratory susceptible strain (SS). The full-length sodium channel gene named AlVSSC encoding 2028 amino acids was obtained by RT-PCR and rapid amplification of cDNA ends (RACE). One single point mutation L1015F in the AlVSSC was detected only in the Shandong population. Our results revealed that the L1015F mutation associated with pyrethroid resistance was identified in A. lucorum populations in China. These results will be useful for the rational chemical control of A. lucorum in the transgenic Bt cotton field. Copyright © 2015 Elsevier Inc. All rights reserved.

Molecular Approaches to Improve the Insecticidal Activity of Bacillus thuringiensis Cry Toxins

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Wagner A. Lucena

2014-08-01

Full Text Available Bacillus thuringiensis (Bt is a gram-positive spore-forming soil bacterium that is distributed worldwide. Originally recognized as a pathogen of the silkworm, several strains were found on epizootic events in insect pests. In the 1960s, Bt began to be successfully used to control insect pests in agriculture, particularly because of its specificity, which reflects directly on their lack of cytotoxicity to human health, non-target organisms and the environment. Since the introduction of transgenic plants expressing Bt genes in the mid-1980s, numerous methodologies have been used to search for and improve toxins derived from native Bt strains. These improvements directly influence the increase in productivity and the decreased use of chemical insecticides on Bt-crops. Recently, DNA shuffling and in silico evaluations are emerging as promising tools for the development and exploration of mutant Bt toxins with enhanced activity against target insect pests. In this report, we describe natural and in vitro evolution of Cry toxins, as well as their relevance in the mechanism of action for insect control. Moreover, the use of DNA shuffling to improve two Bt toxins will be discussed together with in silico analyses of the generated mutations to evaluate their potential effect on protein structure and cytotoxicity.

Hybridization between crops and wild relatives: the contribution of cultivated lettuce to the vigour of crop-wild hybrids under drought, salinity and nutrient deficiency conditions.

Science.gov (United States)

Uwimana, Brigitte; Smulders, Marinus J M; Hooftman, Danny A P; Hartman, Yorike; van Tienderen, Peter H; Jansen, Johannes; McHale, Leah K; Michelmore, Richard W; van de Wiel, Clemens C M; Visser, Richard G F

2012-10-01

With the development of transgenic crop varieties, crop-wild hybridization has received considerable consideration with regard to the potential of transgenes to be transferred to wild species. Although many studies have shown that crops can hybridize with their wild relatives and that the resulting hybrids may show improved fitness over the wild parents, little is still known on the genetic contribution of the crop parent to the performance of the hybrids. In this study, we investigated the vigour of lettuce hybrids using 98 F(2:3) families from a cross between cultivated lettuce and its wild relative Lactuca serriola under non-stress conditions and under drought, salinity and nutrient deficiency. Using single nucleotide polymorphism markers, we mapped quantitative trait loci associated with plant vigour in the F(2:3) families and determined the allelic contribution of the two parents. Seventeen QTLs (quantitative trait loci) associated with vigour and six QTLs associated with the accumulation of ions (Na(+), Cl(-) and K(+)) were mapped on the nine linkage groups of lettuce. Seven of the vigour QTLs had a positive effect from the crop allele and six had a positive effect from the wild allele across treatments, and four QTLs had a positive effect from the crop allele in one treatment and from the wild allele in another treatment. Based on the allelic effect of the QTLs and their location on the genetic map, we could suggest genomic locations where transgene integration should be avoided when aiming at the mitigation of its persistence once crop-wild hybridization takes place.

Strategies for Enhanced Crop Resistance to Insect Pests.

Science.gov (United States)

Douglas, Angela E

2018-04-29

Insect pests are responsible for substantial crop losses worldwide through direct damage and transmission of plant diseases, and novel approaches that complement or replace broad-spectrum chemical insecticides will facilitate the sustainable intensification of food production in the coming decades. Multiple strategies for improved crop resistance to insect pests, especially strategies relating to plant secondary metabolism and immunity and microbiome science, are becoming available. Recent advances in metabolic engineering of plant secondary chemistry offer the promise of specific toxicity or deterrence to insect pests; improved understanding of plant immunity against insects provides routes to optimize plant defenses against insects; and the microbiomes of insect pests can be exploited, either as a target or as a vehicle for delivery of insecticidal agents. Implementation of these advances will be facilitated by ongoing advances in plant breeding and genetic technologies.

Environmental risks and challenges associated with neonicotinoid insecticides

Science.gov (United States)

Hladik, Michelle L.; Main, Anson; Goulson, Dave

2018-01-01

Neonicotinoid use has increased rapidly in recent years, with a global shift towards insecticide applications as seed coatings rather than aerial spraying. While the use of seed coatings can lessen the amount of overspray and drift, the near universal and prophylactic use of neonicotinoid seed coatings on major agricultural crops has led to widespread detections in the environment (pollen, soil, water, honey). Pollinators and aquatic insects appear to be especially susceptible to the effects of neonicotinoids with current research suggesting that chronic sub-lethal effects are more prevalent than acute toxicity. Meanwhile, evidence of clear and consistent yield benefits from the use of neonicotinoids remains elusive for most crops. Future decisions on neonicotinoid use will benefit from weighing crop yield benefits versus environmental impacts to non-target organisms and considering whether there are more environmentally benign alternatives.

Goss’s wilt incidence in sweet corn is independent of transgenic traits and glyphosate

Science.gov (United States)

Recently claims have been made that the use of glyphosate and transgenic crop traits increases the risk of plant diseases. Transgenic traits used widely for years in dent corn are now available in commercial sweet corn cultivars, specifically, the combination of glyphosate resistance (GR) and Lepid...

Glyphosate drift promotes changes in fitness and transgene flow in canola (Brassica napus) and hybrids

Science.gov (United States)

1. With the advent of transgenic crops, genetically modified, herbicide resistant B. napus has become a model system for examining the risks of escape of transgenes from cultivation and for evaluating potential ecological consequences of novel genes in wild species. 2. We exam...

Transgenic perennial biofuel feedstocks and strategies for bioconfinement

Science.gov (United States)

The use of transgenic tools for the improvement of plant feedstocks will be required to realize the full economic and environmental benefits of cellulosic and other biofuels, particularly from perennial plants. Traits that are targets for improvement of biofuels crops include he...

Assessing Dietary Exposure to Pyrethroid Insecticides by LC/MS/MS of Food Composites

Science.gov (United States)

Introduction Pyrethroid insecticides are widely used to control household pests such as cockroaches, for public works control of mosquitoes, and on crops and livestock. Though more toxic to insects than to mammals, some pyrethroids are highly toxic to fish, bees, and cats. Perme...

Single-Event Transgene Product Levels Predict Levels in Genetically Modified Breeding Stacks.

Science.gov (United States)

Gampala, Satyalinga Srinivas; Fast, Brandon J; Richey, Kimberly A; Gao, Zhifang; Hill, Ryan; Wulfkuhle, Bryant; Shan, Guomin; Bradfisch, Greg A; Herman, Rod A

2017-09-13

The concentration of transgene products (proteins and double-stranded RNA) in genetically modified (GM) crop tissues is measured to support food, feed, and environmental risk assessments. Measurement of transgene product concentrations in breeding stacks of previously assessed and approved GM events is required by many regulatory authorities to evaluate unexpected transgene interactions that might affect expression. Research was conducted to determine how well concentrations of transgene products in single GM events predict levels in breeding stacks composed of these events. The concentrations of transgene products were compared between GM maize, soybean, and cotton breeding stacks (MON-87427 × MON-89034 × DAS-Ø15Ø7-1 × MON-87411 × DAS-59122-7 × DAS-40278-9 corn, DAS-81419-2 × DAS-44406-6 soybean, and DAS-21023-5 × DAS-24236-5 × SYN-IR102-7 × MON-88913-8 × DAS-81910-7 cotton) and their component single events (MON-87427, MON-89034, DAS-Ø15Ø7-1, MON-87411, DAS-59122-7, and DAS-40278-9 corn, DAS-81419-2, and DAS-44406-6 soybean, and DAS-21023-5, DAS-24236-5, SYN-IR102-7, MON-88913-8, and DAS-81910-7 cotton). Comparisons were made within a crop and transgene product across plant tissue types and were also made across transgene products in each breeding stack for grain/seed. Scatter plots were generated comparing expression in the stacks to their component events, and the percent of variability accounted for by the line of identity (y = x) was calculated (coefficient of identity, I 2 ). Results support transgene concentrations in single events predicting similar concentrations in breeding stacks containing the single events. Therefore, food, feed, and environmental risk assessments based on concentrations of transgene products in single GM events are generally applicable to breeding stacks composed of these events.

Investigating the Structure-Activity Relationship of the Insecticidal Natural Product Rocaglamide.

Science.gov (United States)

Hall, Roger G; Bruce, Ian; Cooke, Nigel G; Diorazio, Louis J; Cederbaum, Fredrik; Dobler, Markus R; Irving, Ed

2017-12-01

The natural product Rocaglamide (1), isolated from the tree Aglaia elliptifolia, is a compelling but also challenging lead structure for crop protection. In laboratory assays, the natural product shows highly interesting insecticidal activity against chewing pests and beetles, but also phytotoxicity on some crop plants. Multi-step syntheses with control of stereochemistry were required to probe the structure-activity relationship (SAR), and seek simplified analogues. After a significant research effort, just two areas of the molecule were identified which allow modification whilst maintaining activity, as will be highlighted in this paper.

The global status of insect resistance to neonicotinoid insecticides.

Science.gov (United States)

Bass, Chris; Denholm, Ian; Williamson, Martin S; Nauen, Ralf

2015-06-01

The first neonicotinoid insecticide, imidacloprid, was launched in 1991. Today this class of insecticides comprises at least seven major compounds with a market share of more than 25% of total global insecticide sales. Neonicotinoid insecticides are highly selective agonists of insect nicotinic acetylcholine receptors and provide farmers with invaluable, highly effective tools against some of the world's most destructive crop pests. These include sucking pests such as aphids, whiteflies, and planthoppers, and also some coleopteran, dipteran and lepidopteran species. Although many insect species are still successfully controlled by neonicotinoids, their popularity has imposed a mounting selection pressure for resistance, and in several species resistance has now reached levels that compromise the efficacy of these insecticides. Research to understand the molecular basis of neonicotinoid resistance has revealed both target-site and metabolic mechanisms conferring resistance. For target-site resistance, field-evolved mutations have only been characterized in two aphid species. Metabolic resistance appears much more common, with the enhanced expression of one or more cytochrome P450s frequently reported in resistant strains. Despite the current scale of resistance, neonicotinoids remain a major component of many pest control programmes, and resistance management strategies, based on mode of action rotation, are of crucial importance in preventing resistance becoming more widespread. In this review we summarize the current status of neonicotinoid resistance, the biochemical and molecular mechanisms involved, and the implications for resistance management. Copyright © 2015 Elsevier Inc. All rights reserved.

Phytoremediation of the organic Xenobiotic simazine by p450-1a2 transgenic Arabidopsis thaliana plants.

Science.gov (United States)

Azab, Ehab; Hegazy, Ahmad K; El-Sharnouby, Mohamed E; Abd Elsalam, Hassan E

2016-01-01

The potential use of human P450-transgenic plants for phytoremediation of pesticide contaminated soils was tested in laboratory and greenhouse experiments. The transgenic P450 CYP1A2 gene Arabidopsis thaliana plants metabolize number of herbicides, insecticides and industrial chemicals. The P450 isozymes CYP1A2 expressed in A. thaliana were examined regarding the herbicide simazine (SIM). Transgenic A. thaliana plants expressing CYP1A2 gene showed significant resistance to SIM supplemented either in plant growth medium or sprayed on foliar parts. The results showed that SIM produces harmful effect on both rosette diameter and primary root length of the wild type (WT) plants. In transgenic A. thaliana lines, the rosette diameter and primary root length were not affected by SIM concentrations used in this experiment. The results indicate that CYP1A2 can be used as a selectable marker for plant transformation, allowing efficient selection of transgenic lines in growth medium and/or in soil-grown plants. The transgenic A. thaliana plants exhibited a healthy growth using doses of up to 250 μmol SIM treatments, while the non-transgenic A. thaliana plants were severely damaged with doses above 50 μmol SIM treatments. The transgenic A. thaliana plants can be used as phytoremediator of environmental SIM contaminants.

Regional pest suppression associated with widespread Bt maize adoption benefits vegetable growers.

Science.gov (United States)

Dively, Galen P; Venugopal, P Dilip; Bean, Dick; Whalen, Joanne; Holmstrom, Kristian; Kuhar, Thomas P; Doughty, Hélène B; Patton, Terry; Cissel, William; Hutchison, William D

2018-03-27

Transgenic crops containing the bacterium Bacillus thuringiensis (Bt) genes reduce pests and insecticide usage, promote biocontrol services, and economically benefit growers. Area-wide Bt adoption suppresses pests regionally, with declines expanding beyond the planted Bt crops into other non-Bt crop fields. However, the offsite benefits to growers of other crops from such regional suppression remain uncertain. With data spanning 1976-2016, we demonstrate that vegetable growers benefit via decreased crop damage and insecticide applications in relation to pest suppression in the Mid-Atlantic United States. We provide evidence for the regional suppression of Ostrinia nubilalis (Hübner), European corn borer, and Helicoverpa zea (Boddie), corn earworm, populations in association with widespread Bt maize adoption (1996-2016) and decreased economic levels for injury in vegetable crops [peppers ( Capsicum annuum L.), green beans ( Phaseolus vulgaris L.), and sweet corn ( Zea mays L., convar. saccharata )] compared with the pre-Bt period (1976-1995). Moth populations of both species significantly declined in association with widespread Bt maize (field corn) adoption, even as increased temperatures buffered the population reduction. We show marked decreases in the number of recommended insecticidal applications, insecticides applied, and O. nubilalis damage in vegetable crops in association with widespread Bt maize adoption. These offsite benefits to vegetable growers in the agricultural landscape have not been previously documented, and the positive impacts identified here expand on the reported ecological effects of Bt adoption. Our results also underscore the need to account for offsite economic benefits of pest suppression, in addition to the direct economic benefits of Bt crops.

Imaginal and ovicidal effect of some insecticides against Bruchus pisorum L. (Coleoptera: Chrisomelidae

Directory of Open Access Journals (Sweden)

Nikolova I. M.

2015-06-01

Full Text Available Trials were conducted in 2011 and 2012 at the Institute of Forage Crops, Pleven, Bulgaria, in order to study the imaginal and possible ovicidal effect of some insecticides against Bruchus pisorum under field conditions. Treatments with insecticides were started after the appearance of the first pea weevils eggs on pods located on the bottom two nodes. It was found that treatment with acetamiprid; thiacloprid; thiacloprid+deltamethrin; 50 g cypermethrin+480 g chlorpyrifosethyl, 50 g cypermethrin+500 g chlorpyrifosethyl and zeta-cypermethrin resulted in the cessation of additional oviposition on the lower nodes by Bruchus pisorum, due to the toxic effect of the insecticides on the pea weevil. It was found that spraying with acetamiprid and zeta-cypermethrin was the most effective. These insecticides significantly reduced the proportion of infected pods in comparison with the proportion of pods with eggs before the treatment by 30.2 and 27.4% and by 15.8 and 24.0% in 2011 and 2012, respectively. The use of acetamiprid and zeta-cypermethrin was also associated with the lowest percentage of infected seeds (21.7 and 23.6%, respectively, with the lowest percentage of infected seed in infected pods (40.5 and 42.5%, respectively and the highest weight of 1000 infected seeds (161.94 and 182.04 g, respectively. It was concluded that the management of pea weevils in the crop with acetamiprid and zetacypermethrin can lead to satisfactory results when spray timing is chosen when the first eggs are visible.

Type 'A' and 'B' recovery revisited: The role of field-edge habitats for Collembola and macroarthropod community recovery after insecticide treatment

Energy Technology Data Exchange (ETDEWEB)

Frampton, Geoff K. [Ecology and Evolutionary Biology Group, School of Biological Sciences, University of Southampton, Bassett Crescent East, Southampton SO16 7PX (United Kingdom)]. E-mail: gkf@soton.ac.uk; Gould, Philip J.L. [Ecology and Evolutionary Biology Group, School of Biological Sciences, University of Southampton, Bassett Crescent East, Southampton SO16 7PX (United Kingdom); Brink, Paul J. van den [Alterra, Wageningen University and Research Centre, P.O. Box 47, 6700 AA Wageningen (Netherlands); Department of Aquatic Ecology and Water Quality Management, Wageningen University, Wageningen University and Research Centre, Wageningen (Netherlands); Hendy, Eleanor [Ecology and Evolutionary Biology Group, School of Biological Sciences, University of Southampton, Bassett Crescent East, Southampton SO16 7PX (United Kingdom)

2007-02-15

Previous work has identified two patterns of arthropod recovery after insecticide applications to arable crops: dispersal-mediated recolonisation from untreated areas (Type A) and recolonisation within treated areas assisted by reduced predation (Type B). In this study, connectivity between field-edge habitats was manipulated using barriers to investigate whether a crop edge and adjacent hedgerow influence recolonisation of an insecticide-treated crop by surface-active Collembola and other arthropods. Collembola recovery patterns differed among closely-related taxa. Epigeic collembolan and macroarthropod communities were more diverse and abundant, and rates of artificial prey predation were higher, in sprayed crop areas connected to both hedgerow and unsprayed crop edge than in sprayed areas connected to the unsprayed edge alone. These findings indicate that effectiveness of unsprayed crop edges as sources of field recolonisation may depend on adjoining field margin habitats. An assumption in risk assessment that unsprayed crop edges assist population recovery within treated areas is not supported. - Collembola recolonisation differs among species; effectiveness of unsprayed crop edges as sources of arthropod recolonisation may depend on adjacent habitat.

LC-MS/MS analysis of neonicotinoid insecticides: Residue findings in chilean honeys

Directory of Open Access Journals (Sweden)

Raquel Bridi

Full Text Available ABSTRACT Neonicotinoids are a relatively new generation of insecticides that have been used for control of pests such as aphids, leafhoppers and whiteflies. This paper presents for the first time a determination of residues of four neonicotinoid insecticides (acetamiprid, thiamethoxam, thiacloprid and imidacloprid in Chilean honey using QuEChERS extraction and UHPLC-MS/MS analysis. The limits of detection and quantification found for all analytes ranging from 0.34 to 1.43 μg kg-1 and from 0.30 to 4.76 μg kg-1, respectively. The extraction using QuEChERS method provided recoveries over 79% and the precision showed coefficient of variation lower than 20%. These data are in agreement with the international criteria that recommend general recovery limits of 70 - 120%. Of the 16 samples analyzed, in three honey samples neonicotinoids pesticides were detected. These three samples were collected from the same geographical area (Rengo. Fruit and grain production characterize the province of Rengo. The analysis of the botanical origin of these honeys showed the absence of pollen grains of crops and the majority presence of pollen grains of weeds such as Medicago sativa, Galega officinalis and Brassica rapa, which could be associated with crops. Although the residue levels found were low, the results also confirm the actual occurrence of a transfer of neonicotinoid insecticides from exposed honeybees into honey.

Merging Land Use Change Trends and Insecticide Application to Understand Multiple Threats to Honey Bees in North Dakota

Science.gov (United States)

Dixon, D.; Zheng, H.; Otto, C.

2017-12-01

US beekeepers have historically relied on North Dakota for its rich floral grasslands and mild climate to harvest honey and maintain colony growth from May to September. Over 40% of registered apiaries used for crop pollination across the United States pass through the Northern Great Plains region for this reason. However, increased land use change from grassland to row crops has decreased available forage for honey bees and shrunken the already finite landscape suitable for apiary sites. Alongside the introduction of cropland followed the application of insecticides known to impact colony health. While landscape composition is one of the driving factors influencing honey bee productivity and overall health, the further application of insecticides adds an additional threat layer to the changing landscape. USGS E-pest estimates suggest an increasing application per cropland area over the past 10 years for harmful insecticidees including neonicotinoids, organophosphates and pyrethroids. This research aims to capture these trends by utilizing a spatially explicit habitat quality model from InVEST to integrate the following annual data in North Dakota from 2006-2014: (1) habitat suitability basemaps derived from the Cropland Data Layer (CDL); and (2) assign stacked layers of weighted values to those land covers based on estimated insecticide applications on individual crop types within each county year combination. We aim to utilize model outputs to learn where in time and space registered apiaries have experienced this double sided threat of decreased foraged and increased exposure to insecticides, but also ask further questions about how to improve the landscape with different scenarios.

A proteomic study to identify soya allergens--the human response to transgenic versus non-transgenic soya samples.

Science.gov (United States)

Batista, Rita; Martins, Isabel; Jeno, Paul; Ricardo, Cândido Pinto; Oliveira, Maria Margarida

2007-01-01

In spite of being among the main foods responsible for allergic reactions worldwide, soybean (Glycine max)-derived products continue to be increasingly widespread in a variety of food products due to their well-documented health benefits. Soybean also continues to be one of the elected target crops for genetic modification. The aim of this study was to characterize the soya proteome and, specifically, IgE-reactive proteins as well as to compare the IgE response in soya-allergic individuals to genetically modified Roundup Ready soya versus its non-transgenic control. We performed two-dimensional gel electrophoresis of protein extracts from a 5% genetically modified Roundup Ready flour sample and its non-transgenic control followed by Western blotting with plasma from 5 soya-sensitive individuals. We used peptide tandem mass spectrometry to identify soya proteins (55 protein matches), specifically IgE-binding ones, and to evaluate differences between transgenic and non-transgenic samples. We identified 2 new potential soybean allergens--one is maturation associated and seems to be part of the late embryogenesis abundant proteins group and the other is a cysteine proteinase inhibitor. None of the individuals tested reacted differentially to the transgenic versus non-transgenic samples under study. Soybean endogenous allergen expression does not seem to be altered after genetic modification. Proteomics should be considered a powerful tool for functional characterization of plants and for food safety assessment. Copyright (c) 2007 S. Karger AG, Basel.

What risk assessments of genetically modified organisms can learn from institutional analyses of public health risks.

Science.gov (United States)

Rajan, S Ravi; Letourneau, Deborah K

2012-01-01

The risks of genetically modified organisms (GMOs) are evaluated traditionally by combining hazard identification and exposure estimates to provide decision support for regulatory agencies. We question the utility of the classical risk paradigm and discuss its evolution in GMO risk assessment. First, we consider the problem of uncertainty, by comparing risk assessment for environmental toxins in the public health domain with genetically modified organisms in the environment; we use the specific comparison of an insecticide to a transgenic, insecticidal food crop. Next, we examine normal accident theory (NAT) as a heuristic to consider runaway effects of GMOs, such as negative community level consequences of gene flow from transgenic, insecticidal crops. These examples illustrate how risk assessments are made more complex and contentious by both their inherent uncertainty and the inevitability of failure beyond expectation in complex systems. We emphasize the value of conducting decision-support research, embracing uncertainty, increasing transparency, and building interdisciplinary institutions that can address the complex interactions between ecosystems and society. In particular, we argue against black boxing risk analysis, and for a program to educate policy makers about uncertainty and complexity, so that eventually, decision making is not the burden that falls upon scientists but is assumed by the public at large.

What Risk Assessments of Genetically Modified Organisms Can Learn from Institutional Analyses of Public Health Risks

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S. Ravi Rajan

2012-01-01

Full Text Available The risks of genetically modified organisms (GMOs are evaluated traditionally by combining hazard identification and exposure estimates to provide decision support for regulatory agencies. We question the utility of the classical risk paradigm and discuss its evolution in GMO risk assessment. First, we consider the problem of uncertainty, by comparing risk assessment for environmental toxins in the public health domain with genetically modified organisms in the environment; we use the specific comparison of an insecticide to a transgenic, insecticidal food crop. Next, we examine normal accident theory (NAT as a heuristic to consider runaway effects of GMOs, such as negative community level consequences of gene flow from transgenic, insecticidal crops. These examples illustrate how risk assessments are made more complex and contentious by both their inherent uncertainty and the inevitability of failure beyond expectation in complex systems. We emphasize the value of conducting decision-support research, embracing uncertainty, increasing transparency, and building interdisciplinary institutions that can address the complex interactions between ecosystems and society. In particular, we argue against black boxing risk analysis, and for a program to educate policy makers about uncertainty and complexity, so that eventually, decision making is not the burden that falls upon scientists but is assumed by the public at large.

Computational and biological characterization of fusion proteins of two insecticidal proteins for control of insect pests.

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Javaid, Shaista; Naz, Sehrish; Amin, Imran; Jander, Georg; Ul-Haq, Zaheer; Mansoor, Shahid

2018-03-19

Sucking pests pose a serious agricultural challenge, as available transgenic technologies such as Bacillus thuringiensis crystal toxins (Bt) are not effective against them. One approach is to produce fusion protein toxins for the control of these pests. Two protein toxins, Hvt (ω-atracotoxin from Hadronyche versuta) and onion leaf lectin, were translationally fused to evaluate the negative effects of fusion proteins on Phenacoccus solenopsis (mealybug), a phloem-feeding insect pest. Hvt was cloned both N-terminally (HL) and then C-terminally (LH) in the fusion protein constructs, which were expressed transiently in Nicotiana tabacum using a Potato Virus X (PVX) vector. The HL fusion protein was found to be more effective against P. solenopsis, with an 83% mortality rate, as compared to the LH protein, which caused 65% mortality. Hvt and lectin alone caused 42% and 45%, respectively, under the same conditions. Computational studies of both fusion proteins showed that the HL protein is more stable than the LH protein. Together, these results demonstrate that translational fusion of two insecticidal proteins improved the insecticidal activity relative to each protein individually and could be expressed in transgenic plants for effective control of sucking pests.

Plant Essential Oils from Apiaceae Family as Alternatives to Conventional Insecticides

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Asgar Ebadollahi

2013-06-01

Full Text Available Main method to control insect pest is using synthetic insecticides, but the development of insect resistance to this products, the high operational cost, environmental pollution, toxicity to humans and harmful effect on non-target organisms have created the need for developing alternative approaches to control insect pest. Furthermore, the demand for organic crops, especially vegetables for the fresh market, has greatly increased worldwide. The ideal insecticide should control target pests adequately and should be target-specific, rapidly degradable, and low in toxicity to humans and other mammals. Plant essential oils could be an alternative source for insect pest control because they constitute a rich source of bioactive chemicals and are commonly used as flavoring agents in foods. These materials may be applied to food crops shortly before harvest without leaving excessive residues. Moreover, medically safe of these plant derivatives has emphasized also. For these reasons, much effort has been focused on plant essential oils or their constituents as potential sources of insect control agents. In this context, Apiaceae (Umbelliferae family would rank among the most important families of plants. In the last few years more and more studies on the insecticidal properties of essential oils from Apiaceae family have been published and it seemed worthwhile to compile them. The focus of this review lies on the lethal (ovicidal, larvicidal, pupicidal and adulticidal and sublethal (antifeedant, repellent, oviposition deterrent, Growth inhibitory and progeny production activities of plant essential oils and theirmain components from Apiaceae family. These features indicate that pesticides based on Apiaceae essential oils could be used in a variety of ways to control a large number of pests. It can be concluded that essential oils and phytochemicals isolated from Apiaceae family may be efficacious and safe replacements for conventional synthetic

A review of plant protection against the olive fly (Bactrocera oleae (Rossi, 1790 Gmelin and molecular methods to monitor the insecticide resistance alleles

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Matjaž Hladnik

2017-01-01

Full Text Available Olive fly (Bactrocera oleae (Rossi, 1790 Gmelin is one of the most important olive pests worldwide. Most plant protection measures are based on insecticides, especially organophosphates, pyrethroids, and recently a spinosad. Insecticides are used as cover sprays or in more environmentally friendly methods in which insecticides are used in combination with attractants and pheromones as bait sprays or for mass trapping. However, due to negative impacts of insecticides to environment, new plant protection methods are constantly developing with the aim to lower the consumption of insecticides or even to eliminate them by biological control with entomopathogenic organisms, sterile insect technique (SIT, or transgenic method RIDL (release of insects carrying a dominant lethal. However, these methods need to be improved in order to guarantee adequate protection. Alternative methods than those traditionally used are required due to long term usage causing the development of resistance to the insecticides, ultimately lowering their effectiveness. Molecular methods for monitoring the frequencies of resistant alleles and the current status of resistance alleles in olive growing countries are reviewed here.

Global Status of Genetically Modified Crops: Current Trends and Prospects

OpenAIRE

Hautea, Randy A.

2002-01-01

Modern biotechnology-facilitated crop improvement is undoubtedly one of the most significant technological developments in agriculture. The first wave of genetically-modified (GM) or transgenic crops include cultivars with important input traits such as herbicide tolerance and insect resistance. Future products are expected to provide benefits that could include tolerance to environmental stresses and enhanced nutritional content, which can be particularly valuable in crops that are important...

Integrating circadian activity and gene expression profiles to predict chronotoxicity of Drosophila suzukii response to insecticides.

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Hamby, Kelly A; Kwok, Rosanna S; Zalom, Frank G; Chiu, Joanna C

2013-01-01

Native to Southeast Asia, Drosophila suzukii (Matsumura) is a recent invader that infests intact ripe and ripening fruit, leading to significant crop losses in the U.S., Canada, and Europe. Since current D. suzukii management strategies rely heavily on insecticide usage and insecticide detoxification gene expression is under circadian regulation in the closely related Drosophila melanogaster, we set out to determine if integrative analysis of daily activity patterns and detoxification gene expression can predict chronotoxicity of D. suzukii to insecticides. Locomotor assays were performed under conditions that approximate a typical summer or winter day in Watsonville, California, where D. suzukii was first detected in North America. As expected, daily activity patterns of D. suzukii appeared quite different between 'summer' and 'winter' conditions due to differences in photoperiod and temperature. In the 'summer', D. suzukii assumed a more bimodal activity pattern, with maximum activity occurring at dawn and dusk. In the 'winter', activity was unimodal and restricted to the warmest part of the circadian cycle. Expression analysis of six detoxification genes and acute contact bioassays were performed at multiple circadian times, but only in conditions approximating Watsonville summer, the cropping season, when most insecticide applications occur. Five of the genes tested exhibited rhythmic expression, with the majority showing peak expression at dawn (ZT0, 6am). We observed significant differences in the chronotoxicity of D. suzukii towards malathion, with highest susceptibility at ZT0 (6am), corresponding to peak expression of cytochrome P450s that may be involved in bioactivation of malathion. High activity levels were not found to correlate with high insecticide susceptibility as initially hypothesized. Chronobiology and chronotoxicity of D. suzukii provide valuable insights for monitoring and control efforts, because insect activity as well as insecticide timing

Transgenic Anopheles gambiae expressing an antimalarial peptide suffer no significant fitness cost.

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Clare C McArthur

Full Text Available Mosquito-borne diseases present some of the greatest health challenges faced by the world today. In many cases, existing control measures are compromised by insecticide resistance, pathogen tolerance to drugs and the lack of effective vaccines. In light of these difficulties, new genetic tools for disease control programmes, based on the deployment of genetically modified mosquitoes, are seen as having great promise. Transgenic strains may be used to control disease transmission either by suppressing vector populations or by replacing susceptible with refractory genotypes. In practice, the fitness of the transgenic strain relative to natural mosquitoes will be a critical determinant of success. We previously described a transgenic strain of Anopheles gambiae expressing the Vida3 peptide into the female midgut following a blood-meal, which exhibited significant protection against malaria parasites. Here, we investigated the fitness of this strain relative to non-transgenic controls through comparisons of various life history traits. Experiments were designed, as far as possible, to equalize genetic backgrounds and heterogeneity such that fitness comparisons focussed on the presence and expression of the transgene cassette. We also employed reciprocal crosses to identify any fitness disturbance associated with inheritance of the transgene from either the male or female parent. We found no evidence that the presence or expression of the effector transgene or associated fluorescence markers caused any significant fitness cost in relation to larval mortality, pupal sex ratio, fecundity, hatch rate or longevity of blood-fed females. In fact, fecundity was increased in transgenic strains. We did, however, observe some fitness disturbances associated with the route of inheritance of the transgene. Maternal inheritance delayed male pupation whilst paternal inheritance increased adult longevity for both males and unfed females. Overall, in comparison to

Insecticide resistance in Bemisia tabaci Gennadius (Homoptera: Aleyrodidae) and Anopheles gambiae Giles (Diptera: Culicidae) could compromise the sustainability of malaria vector control strategies in West Africa.

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Gnankiné, Olivier; Bassolé, Imael H N; Chandre, Fabrice; Glitho, Isabelle; Akogbeto, Martin; Dabiré, Roch K; Martin, Thibaud

2013-10-01

Insecticides from the organophosphate (OP) and pyrethroid (PY) chemical families, have respectively, been in use for 50 and 30 years in West Africa, mainly against agricultural pests, but also against vectors of human disease. The selection pressure, with practically the same molecules year after year (mainly on cotton), has caused insecticide resistance in pest populations such as Bemisia tabaci, vector of harmful phytoviruses on vegetables. The evolution toward insecticide resistance in malaria vectors such as Anopheles gambiae sensus lato (s.l.) is probably related to the current use of these insecticides in agriculture. Thus, successful pest and vector control in West Africa requires an investigation of insect susceptibility, in relation to the identification of species and sub species, such as molecular forms or biotypes. Identification of knock down resistance (kdr) and acetylcholinesterase gene (Ace1) mutations modifying insecticide targets in individual insects and measure of enzymes activity typically involved in insecticide metabolism (oxidase, esterase and glutathion-S-transferase) are indispensable in understanding the mechanisms of resistance. Insecticide resistance is a good example in which genotype-phenotype links have been made successfully. Insecticides used in agriculture continue to select new resistant populations of B. tabaci that could be from different biotype vectors of plant viruses. As well, the evolution of insecticide resistance in An. gambiae threatens the management of malaria vectors in West Africa. It raises the question of priority in the use of insecticides in health and/or agriculture, and more generally, the question of sustainability of crop protection and vector control strategies in the region. Here, we review the susceptibility tests, biochemical and molecular assays data for B. tabaci, a major pest in cotton and vegetable crops, and An. gambiae, main vector of malaria. The data reviewed was collected in Benin and Burkina

Trade and commerce in improved crops and food: an essay on food security.

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Kershen, Drew L

2010-11-30

Agricultural trade between nations is a significant proportion of total international trade. Agricultural trade in transgenic crops faces extra complications due to the existence of domestic and international regimes that focus specifically on agricultural biotechnology. These specialized regimes create legal and commercial challenges for trade in transgenic crops that have significant implications for the food security of the nations of the world. By food security, one should understand not just the available supply of food, but also the quality of the food and the environmental impact of agricultural production systems. These specialized regimes for transgenic crops can either encourage or hinder the adoption of agricultural biotechnology as a sustainable intensive agriculture. Sustainable intensive agriculture offers hope for agronomic improvements for agricultural production, socio-economic betterment for farmers and environmental benefits for societies. Sustainable intensive agriculture offers particular hope for the poorest farmers of the world because agricultural biotechnology is a technology in the seed. Copyright © 2010 Elsevier B.V. All rights reserved.

Barriers and paths to market for genetically engineered crops.

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Rommens, Caius M

2010-02-01

Each year, billions of dollars are invested in efforts to improve crops through genetic engineering (GE). These activities have resulted in a surge of publications and patents on technologies and genes: a momentum in basic research that, unfortunately, is not sustained throughout the subsequent phases of product development. After more than two decades of intensive research, the market for transgenic crops is still dominated by applications of just a handful of methods and genes. This discrepancy between research and development reflects difficulties in understanding and overcoming seven main barriers-to-entry: (1) trait efficacy in the field, (2) critical product concepts, (3) freedom-to-operate, (4) industry support, (5) identity preservation and stewardship, (6) regulatory approval and (7) retail and consumer acceptance. In this review, I describe the various roadblocks to market for transgenic crops and also discuss methods and approaches on how to overcome these, especially in the United States.

A method for the production and expedient screening of CRISPR/Cas9-mediated non-transgenic mutant plants.

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Chen, Longzheng; Li, Wei; Katin-Grazzini, Lorenzo; Ding, Jing; Gu, Xianbin; Li, Yanjun; Gu, Tingting; Wang, Ren; Lin, Xinchun; Deng, Ziniu; McAvoy, Richard J; Gmitter, Frederick G; Deng, Zhanao; Zhao, Yunde; Li, Yi

2018-01-01

Developing CRISPR/Cas9-mediated non-transgenic mutants in asexually propagated perennial crop plants is challenging but highly desirable. Here, we report a highly useful method using an Agrobacterium -mediated transient CRISPR/Cas9 gene expression system to create non-transgenic mutant plants without the need for sexual segregation. We have also developed a rapid, cost-effective, and high-throughput mutant screening protocol based on Illumina sequencing followed by high-resolution melting (HRM) analysis. Using tetraploid tobacco as a model species and the phytoene desaturase ( PDS ) gene as a target, we successfully created and expediently identified mutant plants, which were verified as tetra-allelic mutants. We produced pds mutant shoots at a rate of 47.5% from tobacco leaf explants, without the use of antibiotic selection. Among these pds plants, 17.2% were confirmed to be non-transgenic, for an overall non-transgenic mutation rate of 8.2%. Our method is reliable and effective in creating non-transgenic mutant plants without the need to segregate out transgenes through sexual reproduction. This method should be applicable to many economically important, heterozygous, perennial crop species that are more difficult to regenerate.

The influence of insecticides and vegetation in structuring Formica mound ant communities (Hymenoptera: Formicidae) in Maine lowbush blueberry.

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Choate, Beth; Drummond, Francis A

2013-04-01

Assessing the influence of new, reduced-risk insecticides on natural enemies within agroecosystems is essential to developing integrated pest management strategies. Three species of mound-building Formica ants are abundant throughout Maine lowbush blueberry fields (Formica exsectoides Forel, F. glacialis Wheeler, and F. ulkei Emery). All three species have been described in the literature as predaceous, with research demonstrating that F. exsectoides preys on major pest insects of lowbush blueberry. The objectives of this study were to determine the impact of common-use and newly introduced insecticides on Formica sp. ant communities in lowbush blueberry fields. Laboratory assays indicated that the commonly applied insecticide phosmet is toxic to F. exsectoides, even after 8 d of field weathering (P insecticides, such as acetamiprid, had little effect on survival of all three species. Abundance of each species in the field varied with lowbush blueberry pesticide-use strategy and amount of nonblueberry vegetation. Both F. exsectoides and F. glacialis were most abundant in organic fields; however, overall F. glacialis was the most abundant in fields of all management types. Field surveys support laboratory results suggesting that phosmet is highly toxic to these species and influences their spatial pattern. Manipulation of the crop to conserve natural enemies in lowbush blueberry is difficult because the crop is not planted; therefore, we must look closely at the incorporation of low toxicity insecticides with natural enemies to efficiently control pest insects.

Africa needs streamlined regulation to support the deployment of GM crops.

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Atkinson, Howard J; Roderick, Hugh; Tripathi, Leena

2015-08-01

Future food security in sub-Saharan Africa (SSA) requires enhancement of its crop production. Transgenic crops with a poverty focus can enhance harvests and are available for staples such as cooking bananas and plantains. One constraint is optimisation of national biosafety processes to support rapid and safe uptake of such beneficial crops. Copyright © 2015 Elsevier Ltd. All rights reserved.

Insecticide solvents: interference with insecticidal action.

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Brattsten, L B; Wilkinson, C F

1977-06-10

Several commercial solvent mixtures commonly used as insecticide carriers in spray formulations increase by more than threefold the microsomal N-demethylation of p-chloro N-methylaniline in midgut preparations of southern army-worm (Spodoptera eridania) larvae exposed orally to the test solvents. Under laboratory conditions, the same solvent mixtures exhibit a protective action against the in vivo toxicity of the insecticide carbaryl to the larvae. The data are discussed with respect to possible solvent-insecticide interactions occurring under field conditions and, more broadly, to potential toxicological hazards of these solvents to humans.

Insecticide resistance and intracellular proteases.

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Wilkins, Richard M

2017-12-01

Pesticide resistance is an example of evolution in action with mechanisms of resistance arising from mutations or increased expression of intrinsic genes. Intracellular proteases have a key role in maintaining healthy cells and in responding to stressors such as pesticides. Insecticide-resistant insects have constitutively elevated intracellular protease activity compared to corresponding susceptible strains. This increase was shown for some cases originally through biochemical enzyme studies and subsequently putatively by transcriptomics and proteomics methods. Upregulation and expression of proteases have been characterised in resistant strains of some insect species, including mosquitoes. This increase in proteolysis results in more degradation products (amino acids) of intracellular proteins. These may be utilised in the resistant strain to better protect the cell from stress. There are changes in insect intracellular proteases shortly after insecticide exposure, suggesting a role in stress response. The use of protease and proteasome inhibitors or peptide mimetics as synergists with improved application techniques and through protease gene knockdown using RNA interference (possibly expressed in crop plants) may be potential pest management strategies, in situations where elevated intracellular proteases are relevant. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Reduced ultraviolet light transmission increases insecticide longevity in protected culture raspberry production.

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Leach, Heather; Wise, John C; Isaacs, Rufus

2017-12-01

High tunnels are large protective structures used for season extension of many crops, including raspberries. These structures are often covered in plastic films to reduce and diffuse ultraviolet light transmission for pest and disease control, but this may also affect the photodegradation and efficacy of pesticides applied under these tunnels. We compared the residue levels of ten insecticides under three tunnel plastics with varying levels of UV transmission and open field conditions. Raspberry plants placed in research-scale tunnels were treated with insecticides and residues on fruit and foliage were monitored for one or two weeks in early 2015 and early and late 2016. Plastics that reduce UV transmission resulted in 50% greater residues of some insecticides compared to transparent plastics, and 60% compared to uncovered tunnels. This increased persistence of residues was evident within 1 day and remained consistently higher for up to 14 days. This pattern was demonstrated for multiple insecticides, including bifenthrin, esfenvalerate, imidacloprid, thiamethoxam, and spinosad. In contrast, the insecticide malathion degraded rapidly regardless of the plastic treatment, indicating less sensitivity to photodegradation. Bioassays using insecticide-treated leaves that were under UV-blocking plastic revealed higher mortality of the invasive fruit pest, Drosophila suzukii, compared to leaves that were uncovered. This indicates that the activity of pesticides under high tunnels covered in UV-reducing plastics may be prolonged, allowing for fewer insecticide applications and longer intervals between sprays. This information can be used to help optimize pest control in protected culture berry production. Copyright © 2017 Elsevier Ltd. All rights reserved.

Companion Cropping as Integrated Pest Management (IPM) Component for Management of Flower Thrips (Thysanoptera: Thripidae) in French Beans (Phasealous Vulgaris L.)

International Nuclear Information System (INIS)

Kasina, J.

2002-01-01

Six companion crops, (Tagetes spp L. (African marigold), Daucus carota L. (carrot), Coriandrum sativum L. (coriander), Brassica spp. L. kale), capsicum spp L. (chilli) and Zea mays (maize) were evaluated for their efficacy in suppressing field populations of the French bean flower thrips, (Frankliniella occidentals (Pergande), Frankliniella schultzei (Trybom) and Megalurothrips sjostedti (trybom). The companion crops were compared to two insecticides, Labda cyhalothrin (Karate 1.75% EC) and Methiocarb (Mesurol 500 SC) and untreated mono-crop of French beans. Three of the treatments, coriander, maize and African marigold were found to be effective in that order, by repelling the pest away from the crop. It is concluded that these crops could be recommended to farmers for use and therefore are able to minimise the high use of chemical insecticides

Environmental effect of conventional and GM crops of cotton (Gossipium hirsitum L. and corn (Zea mays L.

Directory of Open Access Journals (Sweden)

Kelly Ávila

2011-12-01

Full Text Available In the corn belt of Valle de San Juan and in the cotton zone of El Espinal, municipalities in the department of Tolima (Colombia, 10 conventional corn producers, 10 producers of genetically modified corn, five producers of conventional cotton and 15 producers of transgenic cotton were surveyed in the first half of 2009 to contrast the differences in the environmental impact associated with use of insecticides and herbicides, which were evaluated by estimating the environmental index quotient-EIQ. In the case of maize, an EIQ of 42 was found in the conventional type, while transgenic technology had an EIQ of 3.03. In the cultivation of cotton, an EIQ of 263.59 was found for the conventional type while for transgenic technology this value varied between 335.75 (Nuopal BG/RR and 324.79 (DP 455 BG/RR. These data showed a lower environmental impact using GM technology in the cultivation of maize when compared to the conventional counterpart, in connection with the use of insecticides and herbicides, in the context of time, space and genotypic analysis. This effect was not observed in the case of cotton, where environmental impacts were similar

Public Acceptance of Plant Biotechnology and GM Crops.

Science.gov (United States)

Lucht, Jan M

2015-07-30

A wide gap exists between the rapid acceptance of genetically modified (GM) crops for cultivation by farmers in many countries and in the global markets for food and feed, and the often-limited acceptance by consumers. This review contrasts the advances of practical applications of agricultural biotechnology with the divergent paths-also affecting the development of virus resistant transgenic crops-of political and regulatory frameworks for GM crops and food in different parts of the world. These have also shaped the different opinions of consumers. Important factors influencing consumer's attitudes are the perception of risks and benefits, knowledge and trust, and personal values. Recent political and societal developments show a hardening of the negative environment for agricultural biotechnology in Europe, a growing discussion-including calls for labeling of GM food-in the USA, and a careful development in China towards a possible authorization of GM rice that takes the societal discussions into account. New breeding techniques address some consumers' concerns with transgenic crops, but it is not clear yet how consumers' attitudes towards them will develop. Discussions about agriculture would be more productive, if they would focus less on technologies, but on common aims and underlying values.

Overexpressing Exogenous 5-Enolpyruvylshikimate-3-Phosphate Synthase (EPSPS Genes Increases Fecundity and Auxin Content of Transgenic Arabidopsis Plants

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Jia Fang

2018-02-01

Full Text Available Transgenic glyphosate-tolerant plants overproducing EPSPS (5-enolpyruvylshikimate-3-phosphate synthase may exhibit enhanced fitness in glyphosate-free environments. If so, introgression of transgenes overexpressing EPSPS into wild relative species may lead to increased competitiveness of crop-wild hybrids, resulting in unpredicted environmental impact. Assessing fitness effects of transgenes overexpressing EPSPS in a model plant species can help address this question, while elucidating how overproducing EPSPS affects the fitness-related traits of plants. We produced segregating T2 and T3Arabidopsis thaliana lineages with or without a transgene overexpressing EPSPS isolated from rice or Agrobacterium (CP4. For each of the three transgenes, we compared glyphosate tolerance, some fitness-related traits, and auxin (indole-3-acetic acid content in transgene-present, transgene-absent, empty vector (EV, and parental lineages in a common-garden experiment. We detected substantially increased glyphosate tolerance in T2 plants of transgene-present lineages that overproduced EPSPS. We also documented significant increases in fecundity, which was associated with increased auxin content in T3 transgene-present lineages containing rice EPSPS genes, compared with their segregating transgene-absent lineages, EV, and parental controls. Our results from Arabidopsis with nine transgenic events provide a strong support to the hypothesis that transgenic plants overproducing EPSPS can benefit from a fecundity advantage in glyphosate-free environments. Stimulated biosynthesis of auxin, an important plant growth hormone, by overproducing EPSPS may play a role in enhanced fecundity of the transgenic Arabidopsis plants. The obtained knowledge is useful for assessing environmental impact caused by introgression of transgenes overproducing EPSPS from any GE crop into populations of its wild relatives.

Overexpressing Exogenous 5-Enolpyruvylshikimate-3-Phosphate Synthase (EPSPS) Genes Increases Fecundity and Auxin Content of Transgenic Arabidopsis Plants.

Science.gov (United States)

Fang, Jia; Nan, Peng; Gu, Zongying; Ge, Xiaochun; Feng, Yu-Qi; Lu, Bao-Rong

2018-01-01

Transgenic glyphosate-tolerant plants overproducing EPSPS (5-enolpyruvylshikimate-3-phosphate synthase) may exhibit enhanced fitness in glyphosate-free environments. If so, introgression of transgenes overexpressing EPSPS into wild relative species may lead to increased competitiveness of crop-wild hybrids, resulting in unpredicted environmental impact. Assessing fitness effects of transgenes overexpressing EPSPS in a model plant species can help address this question, while elucidating how overproducing EPSPS affects the fitness-related traits of plants. We produced segregating T 2 and T 3 Arabidopsis thaliana lineages with or without a transgene overexpressing EPSPS isolated from rice or Agrobacterium ( CP4 ). For each of the three transgenes, we compared glyphosate tolerance, some fitness-related traits, and auxin (indole-3-acetic acid) content in transgene-present, transgene-absent, empty vector (EV), and parental lineages in a common-garden experiment. We detected substantially increased glyphosate tolerance in T 2 plants of transgene-present lineages that overproduced EPSPS. We also documented significant increases in fecundity, which was associated with increased auxin content in T 3 transgene-present lineages containing rice EPSPS genes, compared with their segregating transgene-absent lineages, EV, and parental controls. Our results from Arabidopsis with nine transgenic events provide a strong support to the hypothesis that transgenic plants overproducing EPSPS can benefit from a fecundity advantage in glyphosate-free environments. Stimulated biosynthesis of auxin, an important plant growth hormone, by overproducing EPSPS may play a role in enhanced fecundity of the transgenic Arabidopsis plants. The obtained knowledge is useful for assessing environmental impact caused by introgression of transgenes overproducing EPSPS from any GE crop into populations of its wild relatives.

TOXICITY OF INSECTICIDES USED IN MUSKMELON ON FIRST-INSTAR LARVAE OF Chrysoperla genanigra FREITAS (NEUROPTERA: CHRYSOPIDAE

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BÁRBARA KARINE DE ALBUQUERQUE SILVA

2017-01-01

Full Text Available Brazil is one of the world's largest producers of melon (Cucumis melo L., and Rio Grande do Norte and Ceará are the largest producers states of the country (99% of exports. This crop had great socio- economic importance in the Brazilian Northeast, however, it is affected by insect pests and consequently, large amounts of pesticides are applied to it, which greatly affect beneficial organisms, such as Chrysopidae. This bioassay evaluated the toxicity of nine insecticides used in commercial crops of muskmelon, applied to first- instar larvae of Chrysoperla genanigra of up to 24-hour-old, from mass rearing cultures. Sublethal effects were evaluated, classifying the insecticides into the toxicity classes recommended by the IOBC. A completely randomized design was used, consisting of ten treatments (clothianidin, pymetrozine, lambda-cyhalothrin, chlorantraniliprole, indoxacarb, pyriproxyfen, beta-cyfluthrin+imidacloprid, imidacloprid, beta-cypermethrin and a control consisted of distilled water. The treatments consisted of exposure of thirty larvae to dry residues of each product in Petri dishes, assessing their mortality, duration of instars, sex ratio, fecundity and viability of eggs from adults of the insects evaluated. The products were classified in toxicity classes as harmful (Class 4 (clothianidin, pymetrozine, indoxacarb, lambda-cyhalothrin, beta-cyfluthrin+imidacloprid, imidacloprid, beta- cypermethrin and pyriproxyfen and innocuous (Class 1 (chlorantraniliprole to first -instar larvae of C. genanigra, by calculate their total effect. Based on this work, chlorantraniliprole is the only recommended insecticide for use in integrated pest management (IPM programs in muskmelon crops.

[Cultivation and environmental impacts of GMO crops].

Science.gov (United States)

Pelletier, Georges

2009-01-01

Transgenic plant varieties are grown since 1996 on surfaces increasing each year. They covered 114 million hectares worldwide in 2007, which shows their success among the farmers in developed as well as developing countries, despite the propaganda campaigns of the environmental movements and advocates of decline. The first transgenic crops (soybean, corn, coton and rapeseed) offer benefits in terms of health, economy and environment. Europe and especially France, which reject this technology, sentence their research to death and penalize their agriculture.

The trends and future of biotechnology crops for insect pest control ...

African Journals Online (AJOL)

Biotech crops, including those that are genetically modified (GM) with Bacillus thuringiensis (Bt) endotoxins for insect resistance, have been cultivated commercially and adopted in steadily increasing numbers of countries over the past 14 years. This review discusses the current status of insect resistant transgenic crops and ...

Influence of the agrochemicals used for rice and vegetable cultivation on insecticide resistance in malaria vectors in southern Côte d'Ivoire.

Science.gov (United States)

Chouaïbou, Mouhamadou S; Fodjo, Behi K; Fokou, Gilbert; Allassane, Ouattara F; Koudou, Benjamin G; David, Jean-Philippe; Antonio-Nkondjio, Christophe; Ranson, Hilary; Bonfoh, Bassirou

2016-08-24

Vector control can contribute to the development of resistance to insecticides in malaria vectors. As the swamps and wetlands used for some agricultural activities constitute productive breeding sites for many mosquito species, agricultural pest control may increase the selection pressure for insecticide resistance in mosquitoes. Understanding the use of agrochemicals by farmers is important to plan and initiate effective integrated pest and vector management interventions. A knowledge-attitude-practice study, using questionnaires, was undertaken with 102 rice farmers in Tiassalé and 106 vegetable farmers in Dabou (South Côte d'Ivoire) in order to generate information on pesticide usage. In addition, insecticide susceptibility bioassays were conducted using adult mosquitoes obtained from larvae collected within farms, and the persistence of agricultural pesticides in the farming environment, including sediment and mosquito breeding site water, was investigated by HPLC. Herbicides and insecticides appeared to be the most frequently used pesticides for both crops. Amino phosphonates (mostly glyphosate) represented the most used herbicides (45 % for rice up to 89 % for vegetables). Pyrethroids appeared to be the most used insecticides (accounting for 90 % of all the insecticide use reported). Approximately 75 % of respondents had not been to school and do not understand product labels. Only about 45 % of farmers respect the recommended pesticide dosage and about 10-15 % of pesticides used for rice and vegetable, respectively, are not recommended for these crops. As per WHO criteria, the mosquito local populations from the two localities were resistant to three of the four insecticides tested, as mortalities were less than 35 % for deltamethrin, DDT and bendiocarb. Higher susceptibility was observed for malathion, although the population was considered resistant in Dabou (80 % mortality) and susceptible in Tiassalé (98 % mortality). With the exception of

PRODUCT NEEM AZAL T/S - BROAD-SPECTRUM PHYPOPESTICIDE FOR CONTROL OF PESTS ON VEGETABLE CROPS

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Vinelina Yankova

2016-09-01

Full Text Available Experiments for determination of the effectiveness of product Neem Azal T/S (a. i. azadirachtin were conducted at a concentration of 0,3% against some major pests in vegetable crops grown in greenhouses at the Maritsa Vegetable Crops research Institute, Plovdiv during the period 2010-2016. It was established very good insecticidal and acaricidal action of phytopesticide against: cotton aphid (Aphis gossypii Glov.; green peach aphid (Myzus persicae Sulz.; western flower trips (Frankliniella occidentalis Perg.; cotton bollworm (Helicoverpa armigera Hubn.; tomato borer (Tuta absoluta Meyrick and two-spotted spider mite (Tetranichus urticae Koch.. This product is a successful alternative to using chemical insecticides and acaricides.

Locus-dependent selection in crop-wild hybrids of lettuce under field conditions and its implication for GM crop development

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Hooftman, Danny A P; Flavell, Andrew J; Jansen, Hans; den Nijs, Hans C M; Syed, Naeem H; Sørensen, Anker P; Orozco-ter Wengel, Pablo; van de Wiel, Clemens C M

2011-01-01

Gene escape from crops has gained much attention in the last two decades, as transgenes introgressing into wild populations could affect the latter's ecological characteristics. However, different genes have different likelihoods of introgression. The mixture of selective forces provided by natural conditions creates an adaptive mosaic of alleles from both parental species. We investigated segregation patterns after hybridization between lettuce (Lactuca sativa) and its wild relative, L. serriola. Three generations of hybrids (S1, BC1, and BC1S1) were grown in habitats mimicking the wild parent's habitat. As control, we harvested S1 seedlings grown under controlled conditions, providing very limited possibility for selection. We used 89 AFLP loci, as well as more recently developed dominant markers, 115 retrotransposon markers (SSAP), and 28 NBS loci linked to resistance genes. For many loci, allele frequencies were biased in plants exposed to natural field conditions, including over-representation of crop alleles for various loci. Furthermore, Linkage disequilibrium was locally changed, allegedly by selection caused by the natural field conditions, providing ample opportunity for genetic hitchhiking. Our study indicates that when developing genetically modified crops, a judicious selection of insertion sites, based on knowledge of selective (dis)advantages of the surrounding crop genome under field conditions, could diminish transgene persistence. PMID:25568012

Locus-dependent selection in crop-wild hybrids of lettuce under field conditions and its implication for GM crop development.

Science.gov (United States)

Hooftman, Danny A P; Flavell, Andrew J; Jansen, Hans; den Nijs, Hans C M; Syed, Naeem H; Sørensen, Anker P; Orozco-Ter Wengel, Pablo; van de Wiel, Clemens C M

2011-09-01

Gene escape from crops has gained much attention in the last two decades, as transgenes introgressing into wild populations could affect the latter's ecological characteristics. However, different genes have different likelihoods of introgression. The mixture of selective forces provided by natural conditions creates an adaptive mosaic of alleles from both parental species. We investigated segregation patterns after hybridization between lettuce (Lactuca sativa) and its wild relative, L. serriola. Three generations of hybrids (S1, BC1, and BC1S1) were grown in habitats mimicking the wild parent's habitat. As control, we harvested S1 seedlings grown under controlled conditions, providing very limited possibility for selection. We used 89 AFLP loci, as well as more recently developed dominant markers, 115 retrotransposon markers (SSAP), and 28 NBS loci linked to resistance genes. For many loci, allele frequencies were biased in plants exposed to natural field conditions, including over-representation of crop alleles for various loci. Furthermore, Linkage disequilibrium was locally changed, allegedly by selection caused by the natural field conditions, providing ample opportunity for genetic hitchhiking. Our study indicates that when developing genetically modified crops, a judicious selection of insertion sites, based on knowledge of selective (dis)advantages of the surrounding crop genome under field conditions, could diminish transgene persistence.

The effect of stereochemistry on the biological activity of natural phytotoxins, fungicides, insecticides and herbicides.

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Evidente, Antonio; Cimmino, Alessio; Andolfi, Anna

2013-02-01

Phytotoxins are secondary microbial metabolites that play an essential role in the development of disease symptoms induced by fungi on host plants. Although phytotoxins can cause extensive-and in some cases devastating-damage to agricultural crops, they can also represent an important tool to develop natural herbicides when produced by fungi and plants to inhibit the growth and spread of weeds. An alternative strategy to biologically control parasitic plants is based on the use of plant and fungal metabolites, which stimulate seed germination in the absence of the host plant. Nontoxigenic fungi also produce bioactive metabolites with potential fungicide and insecticide activity, and could be applied for crop protection. All these metabolites represent important tools to develop eco-friendly pesticides. This review deals with the relationships between the biological activity of some phytotoxins, seed germination stimulants, fungicides and insecticides, and their stereochemistry. Copyright © 2012 Wiley Periodicals, Inc.

TRANSGENIC PLANTS: ENVIRONMENTAL PERSISTENCE AND EFFECTS ON SOIL AND PLANT ECOSYSTEMS

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The genetic engineering of plants has facilitated the production of valuable agricultural and forestry crops. Transgenic plants have been created that have increased resistance to pests, herbicides, pathogens, and environmental stress, enhanced qualitative and quantitative trait...

Genetically modified crops and aquatic ecosystems: considerations for environmental risk assessment and non-target organism testing.

Science.gov (United States)

Carstens, Keri; Anderson, Jennifer; Bachman, Pamela; De Schrijver, Adinda; Dively, Galen; Federici, Brian; Hamer, Mick; Gielkens, Marco; Jensen, Peter; Lamp, William; Rauschen, Stefan; Ridley, Geoff; Romeis, Jörg; Waggoner, Annabel

2012-08-01

Environmental risk assessments (ERA) support regulatory decisions for the commercial cultivation of genetically modified (GM) crops. The ERA for terrestrial agroecosystems is well-developed, whereas guidance for ERA of GM crops in aquatic ecosystems is not as well-defined. The purpose of this document is to demonstrate how comprehensive problem formulation can be used to develop a conceptual model and to identify potential exposure pathways, using Bacillus thuringiensis (Bt) maize as a case study. Within problem formulation, the insecticidal trait, the crop, the receiving environment, and protection goals were characterized, and a conceptual model was developed to identify routes through which aquatic organisms may be exposed to insecticidal proteins in maize tissue. Following a tiered approach for exposure assessment, worst-case exposures were estimated using standardized models, and factors mitigating exposure were described. Based on exposure estimates, shredders were identified as the functional group most likely to be exposed to insecticidal proteins. However, even using worst-case assumptions, the exposure of shredders to Bt maize was low and studies supporting the current risk assessments were deemed adequate. Determining if early tier toxicity studies are necessary to inform the risk assessment for a specific GM crop should be done on a case by case basis, and should be guided by thorough problem formulation and exposure assessment. The processes used to develop the Bt maize case study are intended to serve as a model for performing risk assessments on future traits and crops.

Joint use of fungicides, insecticides and inoculants in the treatment of soybean seeds

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Yara Cristiane Buhl Gomes

Full Text Available ABSTRACT The interference of the joint application of pesticides with seed inoculation on the survival of Bradyrhizobium has been reported in the last years. So, the objective of this study was to evaluate the joint use of fungicides, insecticides and inoculant in the treatment of soybean seeds on various parameters of Bradyrhizobium nodulation in soybean as well as on crop productivity parameters. The experiment was conducted during the 2013/2014 crop in the experimental field of the Instituto Federal de Educação, Ciência e Tecnologia de Mato Grosso - Campo Novo do Parecis Campus. The seeds of TMG 133 RR variety were sown in pots. It was used a randomized block design in a 4 x 4 + 1 factorial, four fungicides (1: fludioxonil + metalaxyl-M, 2: carboxine + thiram, 3: difeconazole and 4: carbendazim + thiram, four insecticides (1: fipronil 250 SC, 2: thiamethoxam, 3: imidacloprid + thiodicarpe and 4: imodacloprid 600 FC and an inoculant (SEMIA 5079 and SEMIA 5080, common to all treatments, with three replications. The experiment was not repeated. The joint application of fungicide and insecticide with inoculant does not affect nodulation, foliar N content and vegetative growth of the plants as well as the masses of grains per plant and 100-grain mass. The use of the carbendazim + thiram mixed with fipronil and carbendazim + thiram mixed with imidacloprid provides less number of pods per plant and grains per plant, reflecting in reductions in the production of soybean grains. In this way, the fungicide carbendazim + thiram, regardless of the combined applied insecticide, is the most harmful to Bradyrhizobium spp.

Rethinking the Risk Management Process for Genetically Engineered Crop Varieties in Small-scale, Traditionally Based Agriculture

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David A. Cleveland

2005-06-01

Full Text Available Proponents of genetically engineered (GE crops often assume that the risk management used in the industrial world is appropriate for small-scale, traditionally based agriculture in the Third World. Opponents of GE crops often assume that risk management is inappropriate for the Third World, because it is inherently biased in favor of the industrial world. We examine both of these assumptions, by rethinking risk management for GE crops and transgenes, using the example of maize transgene flow from the U.S. to Mexico. Risk management for the Third World is a necessary first step of a broader benefit-cost analysis of GE crops, which would include comparisons with existing varieties and with alternative varieties such as transgenic farmer varieties and organic varieties. Our goal is to use existing information on GE crops and on the social and biological characteristics of Third World agriculture to identify key processes that need to be considered in risk management, and the additional research required to adequately understand them. The four main steps in risk management are hazard identification, risk analysis (exposure x harm, risk evaluation, and risk treatment. We use informal event trees to identify possible exposure to GE crops and transgenes, and resulting biological and social harm; give examples of farmers' ability to evaluate social harm; and discuss the possibilities for risk treatment. We conclude that risk management is relevant for Third World agriculture, but needs to be based on the unique biological and social characteristics of small-scale, traditionally based agriculture, including the knowledge and values of Third World farmers and consumers.

A Novel Insecticidal Peptide SLP1 Produced by Streptomyces laindensis H008 against Lipaphis erysimi

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Lijian Xu

2016-08-01

Full Text Available Aphids are major insect pests for crops, causing damage by direct feeding and transmission of plant diseases. This paper was completed to discover and characterize a novel insecticidal metabolite against aphids from soil actinobacteria. An insecticidal activity assay was used to screen 180 bacterial strains from soil samples against mustard aphid, Lipaphis erysimi. The bacterial strain H008 showed the strongest activity, and it was identified by the phylogenetic analysis of the 16S rRNA gene and physiological traits as a novel species of genus Streptomyces (named S. laindensis H008. With the bioassay-guided method, the insecticidal extract from S. laindensis H008 was subjected to chromatographic separations. Finally, a novel insecticidal peptide was purified from Streptomyces laindensis H008 against L. erysimi, and it was determined to be S-E-P-A-Q-I-V-I-V-D-G-V-D-Y-W by TOF-MS and amino acid analysis.

Mdr65 decreases toxicity of multiple insecticides in Drosophila melanogaster.

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Sun, Haina; Buchon, Nicolas; Scott, Jeffrey G

2017-10-01

ABC transporters are ubiquitous membrane-bound proteins, present in both prokaryotes and eukaryotes. The major function of eukaryotic ABC transporters is to mediate the efflux of a variety of substrates (including xenobiotics) out of cells. ABC transporters have been widely investigated in humans, particularly for their involvement in multidrug resistance (MDR). Considerably less is known about their roles in transport and/or excretion in insects. ABC transporters are only known to function as exporters in insects. Drosophila melanogaster has 56 ABC transporter genes, including eight which are phylogenetically most similar to the human Mdr genes (ABCB1 clade). We investigated the role of ABC transporters in the ABCB1 clade in modulating the susceptibility to insecticides. We took advantage of the GAL4/UAS system in D. melanogaster to knockdown the expression levels of Mdr65, Mdr50, Mdr49 and ABCB6 using transgenic UAS-RNAi lines and conditional driver lines. The most notable effects were increased sensitivities to nine different insecticides by silencing of Mdr65. Furthermore, a null mutation of Mdr65 decreased the malathion, malaoxon and fipronil LC 50 values by a factor of 1.9, 2.1 and 3.9, respectively. Altogether, this data demonstrates the critical role of ABC transporters, particularly Mdr65, in altering the toxicity of specific, structurally diverse, insecticides in D. melanogaster. Copyright © 2017 Elsevier Ltd. All rights reserved.

Transgenic Brassica juncea plants expressing MsrA1, a synthetic cationic antimicrobial peptide, exhibit resistance to fungal phytopathogens.

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Rustagi, Anjana; Kumar, Deepak; Shekhar, Shashi; Yusuf, Mohd Aslam; Misra, Santosh; Sarin, Neera Bhalla

2014-06-01

Cationic antimicrobial peptides (CAPs) have shown potential against broad spectrum of phytopathogens. Synthetic versions with desirable properties have been modeled on these natural peptides. MsrA1 is a synthetic chimera of cecropin A and melittin CAPs with antimicrobial properties. We generated transgenic Brassica juncea plants expressing the msrA1 gene aimed at conferring fungal resistance. Five independent transgenic lines were evaluated for resistance to Alternaria brassicae and Sclerotinia sclerotiorum, two of the most devastating pathogens of B. juncea crops. In vitro assays showed inhibition by MsrA1 of Alternaria hyphae growth by 44-62 %. As assessed by the number and size of lesions and time taken for complete leaf necrosis, the Alternaria infection was delayed and restricted in the transgenic plants with the protection varying from 69 to 85 % in different transgenic lines. In case of S. sclerotiorum infection, the lesions were more severe and spread profusely in untransformed control compared with transgenic plants. The sclerotia formed in the stem of untransformed control plants were significantly more in number and larger in size than those present in the transgenic plants where disease protection of 56-71.5 % was obtained. We discuss the potential of engineering broad spectrum biotic stress tolerance by transgenic expression of CAPs in crop plants.

Cross-fertilization between genetically modified and non-genetically modified maize crops in Uruguay.

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Galeano, Pablo; Debat, Claudio Martínez; Ruibal, Fabiana; Fraguas, Laura Franco; Galván, Guillermo A

2010-01-01

The cultivation of genetically modified (GM) Bt maize (Zea mays L.) events MON810 and Bt11 is permitted in Uruguay. Local regulations specify that 10% of the crop should be a non-GM cultivar as refuge area for biodiversity, and the distance from other non-GM maize crops should be more than 250 m in order to avoid cross-pollination. However, the degree of cross-fertilization between maize crops in Uruguay is unknown. The level of adventitious presence of GM material in non-GM crops is a relevant issue for organic farming, in situ conservation of genetic resources and seed production. In the research reported here, the occurrence and frequency of cross-fertilization between commercial GM and non-GM maize crops in Uruguay was assessed. The methodology comprised field sampling and detection using DAS-ELISA and PCR. Five field-pair cases where GM maize crops were grown near non-GM maize crops were identified. These cases had the potential to cross-fertilize considering the distance between crops and the similarity of the sowing dates. Adventitious presence of GM material in the offspring of non-GM crops was found in three of the five cases. Adventitious presence of event MON810 or Bt11 in non-GM maize, which were distinguished using specific primers, matched the events in the putative sources of transgenic pollen. Percentages of transgenic seedlings in the offspring of the non-GM crops were estimated as 0.56%, 0.83% and 0.13% for three sampling sites with distances of respectively 40, 100 and 330 m from the GM crops. This is a first indication that adventitious presence of transgenes in non-GM maize crops will occur in Uruguay if isolation by distance and/or time is not provided. These findings contribute to the evaluation of the applicability of the "regulated coexistence policy" in Uruguay. © ISBR, EDP Sciences, 2011.

Expression of Finger Millet EcDehydrin7 in Transgenic Tobacco Confers Tolerance to Drought Stress.

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Singh, Rajiv Kumar; Singh, Vivek Kumar; Raghavendrarao, Sanagala; Phanindra, Mullapudi Lakshmi Venkata; Venkat Raman, K; Solanke, Amolkumar U; Kumar, Polumetla Ananda; Sharma, Tilak Raj

2015-09-01

One of the critical alarming constraints for agriculture is water scarcity. In the current scenario, global warming due to climate change and unpredictable rainfall, drought is going to be a master player and possess a big threat to stagnating gene pool of staple food crops. So it is necessary to understand the mechanisms that enable the plants to cope with drought stress. In this study, effort was made to prospect the role of EcDehydrin7 protein from normalized cDNA library of drought tolerance finger millet in transgenic tobacco. Biochemical and molecular analyses of T0 transgenic plants were done for stress tolerance. Leaf disc assay, seed germination test, dehydration assay, and chlorophyll estimation showed EcDehydrin7 protein directly link to drought tolerance. Northern and qRT PCR analyses shows relatively high expression of EcDehydrin7 protein compare to wild type. T0 transgenic lines EcDehydrin7(11) and EcDehydrin7(15) shows superior expression among all lines under study. In summary, all results suggest that EcDehydrin7 protein has a remarkable role in drought tolerance and may be used for sustainable crop breeding program in other food crops.

The corporate shaping of GM crops as a technology for the poor

NARCIS (Netherlands)

Glover, D.

2010-01-01

Genetically modified (GM, transgenic) crops are often invoked in debates about poverty, hunger, and agricultural development. The framing of GM crops as a 'pro-poor' and environmentally sustainable technology was partly a creation of the biotechnology industry, but cannot be explained as merely a

DIRProt: a computational approach for discriminating insecticide resistant proteins from non-resistant proteins.

Science.gov (United States)

Meher, Prabina Kumar; Sahu, Tanmaya Kumar; Banchariya, Anjali; Rao, Atmakuri Ramakrishna

2017-03-24

Insecticide resistance is a major challenge for the control program of insect pests in the fields of crop protection, human and animal health etc. Resistance to different insecticides is conferred by the proteins encoded from certain class of genes of the insects. To distinguish the insecticide resistant proteins from non-resistant proteins, no computational tool is available till date. Thus, development of such a computational tool will be helpful in predicting the insecticide resistant proteins, which can be targeted for developing appropriate insecticides. Five different sets of feature viz., amino acid composition (AAC), di-peptide composition (DPC), pseudo amino acid composition (PAAC), composition-transition-distribution (CTD) and auto-correlation function (ACF) were used to map the protein sequences into numeric feature vectors. The encoded numeric vectors were then used as input in support vector machine (SVM) for classification of insecticide resistant and non-resistant proteins. Higher accuracies were obtained under RBF kernel than that of other kernels. Further, accuracies were observed to be higher for DPC feature set as compared to others. The proposed approach achieved an overall accuracy of >90% in discriminating resistant from non-resistant proteins. Further, the two classes of resistant proteins i.e., detoxification-based and target-based were discriminated from non-resistant proteins with >95% accuracy. Besides, >95% accuracy was also observed for discrimination of proteins involved in detoxification- and target-based resistance mechanisms. The proposed approach not only outperformed Blastp, PSI-Blast and Delta-Blast algorithms, but also achieved >92% accuracy while assessed using an independent dataset of 75 insecticide resistant proteins. This paper presents the first computational approach for discriminating the insecticide resistant proteins from non-resistant proteins. Based on the proposed approach, an online prediction server DIRProt has

Chrysodeixis chalcites nucleopolyhedrovirus (ChchNPV): Natural occurrence and efficacy as a biological insecticide on young banana plants in greenhouse and open-field conditions on the Canary Islands.

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Fuentes, Ernesto Gabriel; Hernández-Suárez, Estrella; Simón, Oihane; Williams, Trevor; Caballero, Primitivo

2017-01-01

Chrysodeixis chalcites, an important pest of banana crops on the Canary Islands, is usually controlled by chemical insecticides. The present study aimed to evaluate the efficacy of the most prevalent isolate of the Chrysodeixis chalcites nucleopolyhedrovirus (ChchNPV, Baculoviridae) as a biological insecticide. Overall the prevalence of ChchNPV infection in C. chalcites populations was 2.3% (103 infected larvae out of 4,438 sampled), but varied from 0-4.8% on Tenerife and was usually low (0-2%) on the other islands. On Tenerife, infected larvae were present at 11 out of 17 plantations sampled. The prevalence of infection in larvae on bananas grown under greenhouse structures was significantly higher (3%) than in open-field sites (1.4%). The ChchNPV-TF1 isolate was the most abundant and widespread of four genetic variants of the virus. Application of 1.0x109 viral occlusion bodies (OBs)/l of ChchNPV-TF1 significantly reduced C. chalcites foliar damage in young banana plants as did commonly used pesticides, both in greenhouse and open-field sites. The insecticidal efficacy of ChchNPV-TF1 was similar to that of indoxacarb and a Bacillus thuringiensis (Bt)-based insecticide in one year of trials and similar to Bt in the following year of trails in greenhouse and field crops. However, larvae collected at different time intervals following virus treatments and reared in the laboratory experienced 2-7 fold more mortality than insects from conventional insecticide treatments. This suggests that the acquisition of lethal dose occurred over an extended period (up to 7 days) compared to a brief peak in larvae on plants treated with conventional insecticides. These results should prove useful for the registration of a ChchNPV-based insecticide for integrated management of this pest in banana crops on the Canary Islands.

Chrysodeixis chalcites nucleopolyhedrovirus (ChchNPV: Natural occurrence and efficacy as a biological insecticide on young banana plants in greenhouse and open-field conditions on the Canary Islands.

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Ernesto Gabriel Fuentes

Full Text Available Chrysodeixis chalcites, an important pest of banana crops on the Canary Islands, is usually controlled by chemical insecticides. The present study aimed to evaluate the efficacy of the most prevalent isolate of the Chrysodeixis chalcites nucleopolyhedrovirus (ChchNPV, Baculoviridae as a biological insecticide. Overall the prevalence of ChchNPV infection in C. chalcites populations was 2.3% (103 infected larvae out of 4,438 sampled, but varied from 0-4.8% on Tenerife and was usually low (0-2% on the other islands. On Tenerife, infected larvae were present at 11 out of 17 plantations sampled. The prevalence of infection in larvae on bananas grown under greenhouse structures was significantly higher (3% than in open-field sites (1.4%. The ChchNPV-TF1 isolate was the most abundant and widespread of four genetic variants of the virus. Application of 1.0x109 viral occlusion bodies (OBs/l of ChchNPV-TF1 significantly reduced C. chalcites foliar damage in young banana plants as did commonly used pesticides, both in greenhouse and open-field sites. The insecticidal efficacy of ChchNPV-TF1 was similar to that of indoxacarb and a Bacillus thuringiensis (Bt-based insecticide in one year of trials and similar to Bt in the following year of trails in greenhouse and field crops. However, larvae collected at different time intervals following virus treatments and reared in the laboratory experienced 2-7 fold more mortality than insects from conventional insecticide treatments. This suggests that the acquisition of lethal dose occurred over an extended period (up to 7 days compared to a brief peak in larvae on plants treated with conventional insecticides. These results should prove useful for the registration of a ChchNPV-based insecticide for integrated management of this pest in banana crops on the Canary Islands.

Potential Use of Insecticides and Mineral Oils for the Control of Transmission of Major Aphid-Transmitted Potato Viruses

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Drago Milošević

2012-01-01

Full Text Available Viruses occurring in Serbia and other countries in the region are a huge problem constrainingseed potato production. At lower altitudes, in lowland and hilly regions, wheretable potato production is widely distributed, more than 50% of healthy plants becomeinfected with potato virus Y during one growing season. Under these conditions, seed potatoproduction is hindered due to a high infection pressure of potato virus Y which spreads farmore rapidly compared to leaf roll virus, virus S and other viruses hosted by this plant species.This study tended to clarify a frequent dilemma regarding the use of insecticides in preventingthe infection of healthy plants with potato virus Y and leaf roll virus, given the oraland written recommendations from pesticide manufacturers, agronomists and scientistsin the field of crop protection arising from a logical conclusion that aphid vector controlresults in virus transmission control.The present findings, which are in agreement with reports of authors from other countries,show that the use of insecticides is ineffective in preventing potato virus Y which isnonpersistently transmitted by aphids from an external source of infection.However, insecticides can exhibit efficacy in preventing potato virus Y transmissionfrom infected plants to healthy plants within a crop, which can have an overall positiveeffect only if seed potato is grown in areas that have no external source of infection.The present results and those of other authors show that insecticides are effective inpreventing the infection of healthy plants with persistently transmitted leaf roll virus.Mineral oils provide effective control of potato virus Y by preventing the infection ofpotato plants with the virus. They can be combined with other management practices toprotect seed potato crops against the virus.Given the fact that the initial first-year infection of healthy potato plants with virus Y inrelation to leaf roll virus is approximately 10

Low hybrid onion seed yields relate to honey bee visits and insecticide use

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Rachael Long

2011-07-01

Full Text Available Onion thrips, previously considered of minor importance to hybrid onion seed production in California, vector the newly introduced iris yellow spot virus, a serious pathogen of onions that can cause significant yield losses. Insecticide use to control onion thrips has increased in onion seed fields, coincident with a steep decrease in yields, especially in Colusa County. We examined a number of possible contributing factors and found a strong positive correlation between honey bee activity and onion seed set, indicating that a lack of pollination may be contributing to the reduced yields. In addition, honey bee visits to onion flowers were negatively correlated with the number of insecticides applied per field and field size. Reduced onion seed yields in recent years could be associated with the increase in insecticide use, which may be repelling or killing honey bees, important pollinators of this crop.

Pyrosequencing the transcriptome of the greenhouse whitefly, Trialeurodes vaporariorum reveals multiple transcripts encoding insecticide targets and detoxifying enzymes

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Gorman Kevin

2011-01-01

Full Text Available Abstract Background The whitefly Trialeurodes vaporariorum is an economically important crop pest in temperate regions that has developed resistance to most classes of insecticides. However, the molecular mechanisms underlying resistance have not been characterised and, to date, progress has been hampered by a lack of nucleotide sequence data for this species. Here, we use pyrosequencing on the Roche 454-FLX platform to produce a substantial and annotated EST dataset. This 'unigene set' will form a critical reference point for quantitation of over-expressed messages via digital transcriptomics. Results Pyrosequencing produced around a million sequencing reads that assembled into 54,748 contigs, with an average length of 965 bp, representing a dramatic expansion of existing cDNA sequences available for T. vaporariorum (only 43 entries in GenBank at the time of this publication. BLAST searching of non-redundant databases returned 20,333 significant matches and those gene families potentially encoding gene products involved in insecticide resistance were manually curated and annotated. These include, enzymes potentially involved in the detoxification of xenobiotics and those encoding the targets of the major chemical classes of insecticides. A total of 57 P450s, 17 GSTs and 27 CCEs were identified along with 30 contigs encoding the target proteins of six different insecticide classes. Conclusion Here, we have developed new transcriptomic resources for T. vaporariorum. These include a substantial and annotated EST dataset that will serve the community studying this important crop pest and will elucidate further the molecular mechanisms underlying insecticide resistance.

Binding site alteration is responsible for field-isolated resistance to Bacillus thuringiensis Cry2A insecticidal proteins in two Helicoverpa species.

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Silvia Caccia

Full Text Available BACKGROUND: Evolution of resistance by target pests is the main threat to the long-term efficacy of crops expressing Bacillus thuringiensis (Bt insecticidal proteins. Cry2 proteins play a pivotal role in current Bt spray formulations and transgenic crops and they complement Cry1A proteins because of their different mode of action. Their presence is critical in the control of those lepidopteran species, such as Helicoverpa spp., which are not highly susceptible to Cry1A proteins. In Australia, a transgenic variety of cotton expressing Cry1Ac and Cry2Ab (Bollgard II comprises at least 80% of the total cotton area. Prior to the widespread adoption of Bollgard II, the frequency of alleles conferring resistance to Cry2Ab in field populations of Helicoverpa armigera and Helicoverpa punctigera was significantly higher than anticipated. Colonies established from survivors of F(2 screens against Cry2Ab are highly resistant to this toxin, but susceptible to Cry1Ac. METHODOLOGY/PRINCIPAL FINDINGS: Bioassays performed with surface-treated artificial diet on neonates of H. armigera and H. punctigera showed that Cry2Ab resistant insects were cross-resistant to Cry2Ae while susceptible to Cry1Ab. Binding analyses with (125I-labeled Cry2Ab were performed with brush border membrane vesicles from midguts of Cry2Ab susceptible and resistant insects. The results of the binding analyses correlated with bioassay data and demonstrated that resistant insects exhibited greatly reduced binding of Cry2Ab toxin to midgut receptors, whereas no change in (125I-labeled-Cry1Ac binding was detected. As previously demonstrated for H. armigera, Cry2Ab binding sites in H. punctigera were shown to be shared by Cry2Ae, which explains why an alteration of the shared binding site would lead to cross-resistance between the two Cry2A toxins. CONCLUSION/SIGNIFICANCE: This is the first time that a mechanism of resistance to the Cry2 class of insecticidal proteins has been reported

Entomopathogenic fungi as biological control agents of diamondback moth (Lepidoptera: Plutellidae)and compatibility with chemical insecticides

Science.gov (United States)

The objectives were to evaluate the efficiency of entomopathogenic fungi against Plutella xylostella (L.) and the compatibility of the most virulent isolates with some of the insecticides registered for use on cabbage crops. Pathogenicity tests used isolates of Beauveria bassiana, Metarhizium rileyi...

Using the GENESYS model quantifying the effect of cropping systems on gene escape from GM rape varieties to evaluate and design cropping systems

Directory of Open Access Journals (Sweden)

Colbach Nathalie

2004-01-01

Full Text Available Gene flow in rapeseed is a process taking place both in space and over the years and cannot be studied exclusively by field trials. Consequently, the GENESYS model was developed to quantify the effects of cropping systems on transgene escape from rapeseed crops to rapeseed volunteers in neighbour plots and in the subsequent crops. In the present work, this model was used to evaluate the risk of rape harvest contamination by extraneous genes in various farming systems in case of co-existing GM, conventional and organic crops. When 50 % of the rape varieties in the region were transgenic, the rate of GM seeds in non-GM crop harvests on farms with large fields was lower than the 0.9 % purity threshold proposed by the EC for rape crop production (food and feed harvests, but on farms with smaller fields, the threshold was exceeded. Harvest impurity increased in organic farms, mainly because of their small field size. The model was then used to evaluate the consequences of changes in farming practices and to identify those changes reducing harvest contamination. The effects of these changes depended on the field pattern and farming system. The most efficient practices in limiting harvest impurity comprised improved set-aside management by sowing a cover crop in spring on all set-aside fields in the region, permanently banning rape crops and set-aside around seed production fields and (for non-GM farmers clustering farm fields to reduce gene inflow from neighbour fields.

Genomic and environmental selection patterns in two distinct lettuce crop-wild hybrid crosses

NARCIS (Netherlands)

Hartman, Y.; Uwimana, B; Hooftman, D.A.P.; Schranz, M.E.; van de Wiel, C.C.M.; Smulders, M.J.M.; Visser, R.G.F.; van Tienderen, P.H.

2013-01-01

Genomic selection patterns and hybrid performance influence the chance that crop (trans)genes can spread to wild relatives. We measured fitness(-related) traits in two different field environments employing two different crop-wild crosses of lettuce. We performed quantitative trait loci (QTL)

Locus-dependent selection in crop-wild hybrids of lettuce under field conditions and its implication for GM crop development

NARCIS (Netherlands)

Hooftman, D.A.P.; Flavell, A.J.; Jansen, H.; den Nijs, H.C.M.; Syed, N.H.; Sørensen, A.P.; Orozco-ter Wengel, P.; van de Wiel, C.C.M.

2011-01-01

Gene escape from crops has gained much attention in the last two decades, as transgenes introgressing into wild populations could affect the latter’s ecological characteristics. However, different genes have different likelihoods of introgression. The mixture of selective forces provided by natural

The evolution of insecticide resistance in the brown planthopper (Nilaparvata lugens Stål) of China in the period 2012-2016.

Science.gov (United States)

Wu, Shun-Fan; Zeng, Bin; Zheng, Chen; Mu, Xi-Chao; Zhang, Yong; Hu, Jun; Zhang, Shuai; Gao, Cong-Fen; Shen, Jin-Liang

2018-03-15

The brown planthopper, Nilaparvata lugens, is an economically important pest on rice in Asia. Chemical control is still the most efficient primary way for rice planthopper control. However, due to the intensive use of insecticides to control this pest over many years, resistance to most of the classes of chemical insecticides has been reported. In this article, we report on the status of eight insecticides resistance in Nilaparvata lugens (Stål) collected from China over the period 2012-2016. All of the field populations collected in 2016 had developed extremely high resistance to imidacloprid, thiamethoxam, and buprofezin. Synergism tests showed that piperonyl butoxide (PBO) produced a high synergism of imidacloprid, thiamethoxam, and buprofezin effects in the three field populations, YA2016, HX2016, and YC2016. Functional studies using both double-strand RNA (dsRNA)-mediated knockdown in the expression of CYP6ER1 and transgenic expression of CYP6ER1 in Drosophila melanogaster showed that CYP6ER1 confers imidacloprid, thiamethoxam and buprofezin resistance. These results will be beneficial for effective insecticide resistance management strategies to prevent or delay the development of insecticide resistance in brown planthopper populations.

Fipronil insecticide: novel photochemical desulfinylation with retention of neurotoxicity

International Nuclear Information System (INIS)

Hainzl, D.; Casida, J.E.

1996-01-01

Fipronil is an outstanding new insecticide for crop protection with good selectivity between insects and mammals. The insecticidal action involves blocking the gamma-aminobutyric acid-gated chloride channel with much greater sensitivity of this target in insects than in mammals. Fipronil contains a trifluoromethylsulfinyl moiety that is unique among the agrochemicals and therefore presumably important in its outstanding performance. We find that this substituent unexpectedly undergoes a novel and facile photoextrusion reaction on plants upon exposure to sunlight, yielding the corresponding trifluoromethylpyrazole, i.e., the desulfinyl derivative. The persistence of this photoproduct and its high neuroactivity, resulting from blocking the gamma-aminobutyric acid-gated chloride channel, suggest that it may be a significant contributor to the effectiveness of fipronil. In addition, desulfinylfipronil is not a metabolite in mammals, so the safety evaluations must take into account not only the parent compound but also this completely new environmental product

Voltage-gated sodium channels as targets for pyrethroid insecticides.

Science.gov (United States)

Field, Linda M; Emyr Davies, T G; O'Reilly, Andrias O; Williamson, Martin S; Wallace, B A

2017-10-01

The pyrethroid insecticides are a very successful group of compounds that have been used extensively for the control of arthropod pests of agricultural crops and vectors of animal and human disease. Unfortunately, this has led to the development of resistance to the compounds in many species. The mode of action of pyrethroids is known to be via interactions with the voltage-gated sodium channel. Understanding how binding to the channel is affected by amino acid substitutions that give rise to resistance has helped to elucidate the mode of action of the compounds and the molecular basis of their selectivity for insects vs mammals and between insects and other arthropods. Modelling of the channel/pyrethroid interactions, coupled with the ability to express mutant channels in oocytes and study function, has led to knowledge of both how the channels function and potentially how to design novel insecticides with greater species selectivity.

Effects of seed mixture sowing with transgenic Bt rice and its parental line on the population dynamics of target stemborers and leafrollers, and non-target planthoppers.

Science.gov (United States)

Li, Zhuo; Li, Li-Kun; Liu, Bin; Wang, Long; Parajulee, Megha N; Chen, Fa-Jun

2018-01-24

The widespread planting of insect-resistant crops has caused a dramatic shift in agricultural landscapes, thus raising concerns about the potential impacts on both target and non-target pests. In this study, we examined the potential effects of intra-specific seed mixture sowing with transgenic Bt rice (Bt) and its parental non-transgenic line (Nt) (100% Bt rice [Bt 100 ], 5% Nt+95% Bt [Nt 05 Bt 95 ], 10% Nt+90% Bt [Nt 10 Bt 90 ], 20% Nt+80% Bt [Nt 20 Bt 80 ], 40% Nt+60% Bt [Nt 40 Bt 60 ] and 100% Nt rice [Nt 100 ]) on target and non-target pests in a 2-year field trial in southern China. The occurrence of target pests, Sesamia inferens, Chilo suppressalis and Cnaphalocrocis medinalis, decreased with the increased ratio of Bt rice, and the mixture ratios with more than 90% Bt rice (Bt 100 and Nt 05 Bt 95 ) significantly increased the pest suppression efficiency, with the lowest occurrences of non-target planthoppers, Nilaparvata lugens and Sogatella furcifera in Nt 100 and Nt 05 Bt 95 . Furthermore, there were no significant differences in 1000-grain dry weight and grain dry weight per 100 plants between Bt 100 and Nt 05 Bt 95 . Seed mixture sowing of Bt rice with ≤10% (especially 5%) of its parent line was sufficient to overcome potential compliance issues that exist with the use of block or structured refuge to provide most effective control of both target and non-target pests without compromising the grain yield. It is also expected that the strategy of seed mixture sowing with transgenic Bt rice and the non-transgenic parental line would provide rice yield stability while decreasing the insecticide use frequency in rice production. © 2018 Institute of Zoology, Chinese Academy of Sciences.

The neonicotinoid insecticide imidacloprid repels pollinating flies and beetles at field-realistic concentrations.

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Amy H Easton

Full Text Available Neonicotinoids are widely used systemic insecticides which, when applied to flowering crops, are translocated to the nectar and pollen where they may impact upon pollinators. Given global concerns over pollinator declines, this potential impact has recently received much attention. Field exposure of pollinators to neonicotinoids depends on the concentrations present in flowering crops and the degree to which pollinators choose to feed upon them. Here we describe a simple experiment using paired yellow pan traps with or without insecticide to assess whether the commonly used neonicotinoid imidacloprid repels or attracts flying insects. Both Diptera and Coleoptera exhibited marked avoidance of traps containing imidacloprid at a field-realistic dose of 1 µg L(-1, with Diptera avoiding concentrations as low as 0.01 µg L(-1. This is to our knowledge the first evidence for any biological activity at such low concentrations, which are below the limits of laboratory detection using most commonly available techniques. Catch of spiders in pan traps was also slightly reduced by the highest concentrations of imidacloprid used (1 µg L(-1, but catch was increased by lower concentrations. It remains to be seen if the repellent effect on insects occurs when neonicotinoids are present in real flowers, but if so then this could have implications for exposure of pollinators to neonicotinoids and for crop pollination.

Drought tolerance and proteomics studies of transgenic wheat containing the maize C4 phosphoenolpyruvate carboxylase (PEPC) gene.

Science.gov (United States)

Qin, Na; Xu, Weigang; Hu, Lin; Li, Yan; Wang, Huiwei; Qi, Xueli; Fang, Yuhui; Hua, Xia

2016-11-01

Enhancing drought tolerance of crops has been a great challenge in crop improvement. Here, we report the maize phosphoenolpyruvate carboxylase (PEPC) gene was able to confer drought tolerance and increase grain yield in transgenic wheat (Triticum aestivum L.) plants. The improved of drought tolerance was associated with higher levels of proline, soluble sugar, soluble protein, and higher water use efficiency. The transgenic wheat plants had also a more extensive root system as well as increased photosynthetic capacity during stress treatments. The increased grain yield of the transgenic wheat was contributed by improved biomass, larger spike and grain numbers, and heavier 1000-grain weight under drought-stress conditions. Under non-stressed conditions, there were no significant increases in these of the measured traits except for photosynthetic rate when compared with parental wheat. Proteomic research showed that the expression levels of some proteins, including chlorophyll A-B binding protein and pyruvate, phosphate dikinase, which are related to photosynthesis, PAP fibrillin, which is involved in cytoskeleton synthesis, S-adenosylmethionine synthetase, which catalyzes methionine synthesis, were induced in the transgenic wheat under drought stress. Additionally, the expression of glutamine synthetase, which is involved in ammonia assimilation, was induced by drought stress in the wheat. Our study shows that PEPC can improve both stress tolerance and grain yield in wheat, demonstrating the efficacy of PEPC in crop improvement.

Expression of a cystatin transgene in eggplant provides resistance to root-knot nematode, Meloidogyne incognita

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Pradeep Kumar Papolu

2016-07-01

Full Text Available Root-knot nematodes (RKN cause substantial yield decline in eggplant and sustainable management options to minimize crop damage due to nematodes are still limited. A number of genetic engineering strategies have been developed to disrupt the successful plant-nematode interactions. Among them, delivery of proteinase inhibitors from the plant to perturb nematode development and reproduction is arguably the most effective strategy. In the present study, transgenic eggplant expressing a modified rice cystatin (OC-IΔD86 gene under the control of the root-specific promoter, TUB-1, was generated to evaluate the genetically modified nematode resistance. Five putative transformants were selected through PCR and genomic Southern blot analysis. Expression of the cystatin transgene was confirmed in all the events using western blotting, ELISA and qPCR assay. Upon challenge inoculation, all the transgenic events exhibited a detrimental effect on RKN development and reproduction. The best transgenic line (a single copy event showed 78.3% inhibition in reproductive success of RKN. Our results suggest that cystatins can play an important role for improving nematode resistance in eggplant and their deployment in gene pyramiding strategies with other proteinase inhibitors could ultimately enhance crop yield.

The response of transgenic Brassica species to salt stress: a review.

Science.gov (United States)

Shah, Nadil; Anwar, Sumera; Xu, Jingjing; Hou, Zhaoke; Salah, Akram; Khan, Shahbaz; Gong, Jianfang; Shang, Zhengwei; Qian, Li; Zhang, Chunyu

2018-06-01

Salt stress is considered one of the main abiotic factors to limit crop growth and productivity by affecting morpho-physiological and biochemical processes. Genetically, a number of salt tolerant Brassica varieties have been developed and introduced, but breeding of such varieties is time consuming. Therefore, current focus is on transgenic technology, which plays an important role in the development of salt tolerant varieties. Various salt tolerant genes have been characterized and incorporated into Brassica. Therefore, such genetic transformation of Brassica species is a significant step for improvement of crops, as well as conferring salt stress resistance qualities to Brassica species. Complete genome sequencing has made the task of genetically transforming Brassica species easier, by identifying desired candidate genes. The present review discusses relevant information about the principles which should be employed to develop transgenic Brassica species, and also will recommend tools for improved tolerance to salinity.

Impact of planting dates and insecticide strategies for managing crucifer flea beetles (Coleoptera: Chrysomelidae) in spring-planted canola.

Science.gov (United States)

Knodel, Janet J; Olson, Denise L; Hanson, Bryan K; Henson, Robert A

2008-06-01

Integration of cultural practices, such as planting date with insecticide-based strategies, was investigated to determine best management strategy for flea beetles (Phyllotreta spp.) (Coleoptera: Chrysomelidae) in canola (Brassica napus L.). We studied the effect of two spring planting dates of B. napus and different insecticide-based management strategies on the feeding injury caused by fleabeetles in North Dakota during 2002-2003. Adult beetle peak emergence usually coincided with the emergence of the early planted canola, and this resulted in greater feeding injury in the early planted canola than later planted canola. Use of late-planted canola may have limited potential for cultural control of flea beetle, because late-planted canola is at risk for yield loss due to heat stress during flowering. Flea beetle injury ratings declined when 1) the high rate of insecticide seed treatment plus a foliar insecticide applied 21 d after planting was used, 2) the high rate of insecticide seed treatment only was used, or 3) two foliar insecticide sprays were applied. These insecticide strategies provided better protection than the low rates of insecticide seed treatments or a single foliar spray, especially in areas with moderate-to-high flea beetle populations. The foliar spray on top of the seed treatment controlled later-emerging flea beetles as the seed treatment residual was diminishing and the crop became vulnerable to feeding injury. The best insecticide strategy for management of flea beetle was the high rate of insecticide seed treatment plus a foliar insecticide applied at 21 d after planting, regardless of planting date.

Insecticide control of vector-borne diseases: when is insecticide resistance a problem?

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Ana Rivero

Full Text Available Many of the most dangerous human diseases are transmitted by insect vectors. After decades of repeated insecticide use, all of these vector species have demonstrated the capacity to evolve resistance to insecticides. Insecticide resistance is generally considered to undermine control of vector-transmitted diseases because it increases the number of vectors that survive the insecticide treatment. Disease control failure, however, need not follow from vector control failure. Here, we review evidence that insecticide resistance may have an impact on the quality of vectors and, specifically, on three key determinants of parasite transmission: vector longevity, competence, and behaviour. We argue that, in some instances, insecticide resistance is likely to result in a decrease in vector longevity, a decrease in infectiousness, or in a change in behaviour, all of which will reduce the vectorial capacity of the insect. If this effect is sufficiently large, the impact of insecticide resistance on disease management may not be as detrimental as previously thought. In other instances, however, insecticide resistance may have the opposite effect, increasing the insect's vectorial capacity, which may lead to a dramatic increase in the transmission of the disease and even to a higher prevalence than in the absence of insecticides. Either way-and there may be no simple generality-the consequence of the evolution of insecticide resistance for disease ecology deserves additional attention.

Systemic insecticides (neonicotinoids and fipronil): trends, uses, mode of action and metabolites : Environmental Science and Pollution Research

NARCIS (Netherlands)

Simon-Delso, N.; Amaral-Rogers, V.; Belzunces, L.P.; Bonmatin, J.M.; Chagnon, M.; Downs, C.; Furlan, L.; Gibbons, D.W.; Giorio, C.; Girolami, V.; Goulson, D.; Kreutzweiser, D.P.; Krupke, C.H.; Liess, M.; Long, E.; McField, M.; Mineau, P.; Mitchell, E.A.D.; Morrissey, C.A.; Noome, D.A.; Pisa, L.; Settele, J.; Stark, J.D.; Tapparo, A.; Van Dyck, H.; Van Praagh, J.; Van der Sluijs, J.P.; Whitehorn, P.R.; Wiemers, M.

2015-01-01

Since their discovery in the late 1980s, neonicotinoid pesticides have become the most widely used class of insecticides worldwide, with large-scale applications ranging from plant protection (crops, vegetables, fruits), veterinary products, and biocides to invertebrate pest control in fish farming.

More than one rabbit out of the hat: Radiation, transgenic and symbiont-based approaches for sustainable management of mosquito and tsetse fly populations

International Nuclear Information System (INIS)

Bourtzis, K.; Lees, R.S.; Hendrichs, J.; Vreysen, M.J.B.

2016-01-01

Mosquitoes (Diptera: Culicidae) and tsetse flies (Diptera: Glossinidae) are bloodsucking vectors of human and animal pathogens. Mosquito-borne diseases (malaria, filariasis, dengue, chikungunya and Zika) cause severe mortality and morbidity annually, and tsetse fly-borne diseases (African trypanosomes causing sleeping sickness in humans and nagana in livestock) cost Sub-Saharan Africa an estimated US$ 4750 million annually. Current reliance on insecticides for vector control is unsustainable: due to increasing insecticide resistance and growing concerns about health and environmental impacts of chemical control there is a growing need for novel, effective and safe biologically- based methods that are more sustainable. The integration of the sterile insect technique has proven successful to manage crop pests and disease vectors, particularly tsetse flies, and is likely to prove effective against mosquito vectors, particularly once sexseparation methods are improved. Transgenic and symbiont-based approaches are in development, and more advanced in (particularly Aedes) mosquitoes than in tsetse flies; however, issues around stability, sustainability and biosecurity have to be addressed, especially when considering population replacement approaches. Regulatory issues and those relating to intellectual property and economic cost of application must also be overcome. Standardised methods to assess insect quality are required to compare and predict efficacy of the different approaches. Different combinations of these three approaches could be integrated to maximise their benefits, and all have the potential to be used in tsetse and mosquito area-wide integrated pest management programmes. (author)

Effect of Piperonyl Butoxide on the Toxicity of Four Classes of Insecticides to Navel Orangeworm (Amyelois transitella) (Lepidoptera: Pyralidae).

Science.gov (United States)

Demkovich, Mark; Dana, Catherine E; Siegel, Joel P; Berenbaum, May R

2015-12-01

Amyelois transitella (Walker) (Lepidoptera: Pyralidae), the navel orangeworm, is a highly polyphagous economic pest of almond, pistachio, and walnut crops in California. Increasing demand for these crops and their rising economic value has resulted in substantial increases of insecticide applications to reduce damage to acceptable levels. The effects of piperonyl butoxide (PBO), a methylenedioxyphenyl compound that can act as a synergist by inhibiting cytochrome P450-mediated detoxification on insecticide metabolism by A. transitella, were examined in a series of feeding bioassays with first-instar A. transitella larvae from a laboratory strain. PBO, however, can have a variety of effects on metabolism, including inhibition of glutathione-S-transferases and esterases and induction of P450s. In our study, PBO synergized the toxicity of acetamiprid, λ-cyhalothrin, and spinosad, suggesting possible involvement of P450s in their detoxification. In contrast, PBO interacted antagonistically with the organophosphate insecticide chlorpyrifos, reducing its toxicity, an effect consistent with inhibition of P450-mediated bioactivation of this pesticide. The toxicity of the anthranilic diamide insecticide chlorantraniliprole was not altered by PBO, suggestive of little or no involvement of P450-mediated metabolism in its detoxification. Because a population of navel orangeworm in Kern County, CA, has already acquired resistance to the pyrethroid insecticide bifenthrin through enhanced P450 activity, determining the effect of adding a synergist such as PBO on detoxification of all insecticide classes registered for use in navel orangeworm management can help to develop rotation practices that may delay resistance acquisition or to implement alternative management practices where resistance is likely to evolve. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Control of Fusarium verticillioides (Sacc. Nirenberg and Fumonisins by Using a Combination of Crop Protection Products and Fertilization

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Richard Raphael Madege

2018-02-01

Full Text Available Fusarium verticillioides is the most common fungal pathogen associated with maize ear rot in Tanzania. In a two-year trial, we investigated the efficacy of crop protection (insecticide and/or fungicide and fertilizer (nitrogen and/or phosphorus treatments in reducing the occurrence of F. verticillioides and its mycotoxins in maize grown in Tanzania. Seasonal differences were seen to have a substantial influence on the incidence and severity of insect infestation, Fusarium ear and kernel rot, biomass of F. verticillioides and contamination with fumonisins. With regard to the application of fertilizers, it was concluded that the impact on maize stalk borer injury, Fusarium symptoms and fumonisin levels was not significant, whereas crop protection significantly reduced maize damage. The application of an insecticide was most effective in reducing insect injury and as a result of the reduced insect injury the insecticide treatment also resulted in a significant decrease in Fusarium symptoms. In 2014, fumonisin levels were also significantly lower in maize treated with an insecticide. Additionally, significant positive correlations between insect damage and Fusarium symptoms were observed. In conclusion, this study clearly shows that application of an insecticide alone or in combination with a fungicide at anthesis significantly reduces insect damage and consequently reduces F. verticillioides infection and associated fumonisin contamination.

Cry64Ba and Cry64Ca, Two ETX/MTX2-Type Bacillus thuringiensis Insecticidal Proteins Active against Hemipteran Pests.

Science.gov (United States)

Liu, Yonglei; Wang, Yinglong; Shu, Changlong; Lin, Kejian; Song, Fuping; Bravo, Alejandra; Soberón, Mario; Zhang, Jie

2018-02-01

Genetically modified crops that express insecticidal Bacillus thuringiensis (Bt) proteins have become a primary approach for control of lepidopteran (moth) and coleopteran (beetle) pests that feed by chewing the plants. However, the sap-sucking insects (Hemiptera) are not particularly susceptible to Bt toxins. In this study, we describe two Cry toxins (Cry64Ba and Cry64Ca) from Bt strain 1012 that showed toxicity against two important hemipteran rice pests, Laodelphax striatellus and Sogatella furcifera Both of these proteins contain an ETX/MTX2 domain and share common sequence features with the β-pore-forming toxins. Coexpression of cry64Ba and cry64Ca genes in the acrystalliferous Bt strain HD73 - resulted in high insecticidal activity against both hemipteran pests. No toxicity was observed on other pests such as Ostrinia furnacalis , Plutella xylostella , or Colaphellus bowringi Also, no hemolytic activity or toxicity against cancer cells was detected. Binding assays showed specific binding of the Cry64Ba/Cry64Ca toxin complex to brush border membrane vesicles isolated from L. striatellus Cry64Ba and Cry64Ca are Bt Cry toxins highly effective against hemipteran pests and could provide a novel strategy for the environmentally friendly biological control of rice planthoppers in transgenic plants. IMPORTANCE In Asia, rice is an important staple food, whose production is threatened by rice planthoppers. To date, no effective Bacillus thuringiensis (Bt) protein has been shown to have activity against rice planthoppers. We cloned two Bt toxin genes from Bt strain 1012 that showed toxicity against small brown planthoppers ( Laodelphax striatellus ) and white-backed planthoppers ( Sogatella furcifera ). To our knowledge, the proteins encoded by the cry64Ba and cry64Ca genes are the most efficient insecticidal Bt Cry proteins with activity against hemipteran insects reported so far. Cry64Ba and Cry64Ca showed no toxicity against some lepidopteran or coleopteran pests

Pests, diseases and crop protection practices in the smallholder sweetpotato production system of the highlands of Papua New Guinea

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Geoff M. Gurr

2016-12-01

Full Text Available Sweetpotato (Ipomea batatans is a food crop of global significance. The storage roots and foliage of crop are attacked by a wide range of pests and diseases. Whilst these are generally well controlled in developed countries using approaches such as clean planting material and monitoring with pheromone traps to guide insecticide use, research into methods suitable for developing countries has lagged. In Papua New Guinea (PNG, sweetpotato is grown extensively as a subsistence crop and commercial production as a cash crop is developing. We report results from a survey of 33 smallholder producers located in the Highlands of PNG where the crop is of particular importance. Surveys of interviewees’ crops showed high levels of pest and disease impact to foliage, stems and storage roots, especially in crops that were several years old. Weevils (Curculionidae were reportedly the most damaging pests and scab (caused by the fungus Elisnoe batatus the most damaging disease. Most producers reported root damage from the former and foliar damage from the latter but the general level of knowledge of pest and disease types was low. Despite the apparency of pest and disease signs and symptoms and recognition of their importance by farmers, a large majority of producers reported practiced no active pest or disease management. This was despite low numbers of farmers reporting use of traditional cultural practices including phytosanitary measures and insecticidal plants that had the scope for far wider use. Only one respondent reported use of insecticide though pesticides were available in nearby cities. This low level of pest and disease management in most cases, likely due to paucity in biological and technical knowledge among growers, hampers efforts to establish food security and constrains the development of sweetpotato as a cash crop.

Transgenic crops: Current challenges and future perspectives | Ali ...

African Journals Online (AJOL)

resistance, use of selectable marker genes, etc. There exists a thought that the pace of research in genetic engineering of crop plants may some day lead to the development of variations that will not ensure the survival of living creatures including human beings. Most of such concerns are just psychological and are often ...

No evidence for change in oviposition behaviour of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) after widespread adoption of transgenic insecticidal cotton.

Science.gov (United States)

Zalucki, M P; Cunningham, J P; Downes, S; Ward, P; Lange, C; Meissle, M; Schellhorn, N A; Zalucki, J M

2012-08-01

Cotton growing landscapes in Australia have been dominated by dual-toxin transgenic Bt varieties since 2004. The cotton crop has thus effectively become a sink for the main target pest, Helicoverpa armigera. Theory predicts that there should be strong selection on female moths to avoid laying on such plants. We assessed oviposition, collected from two cotton-growing regions, by female moths when given a choice of tobacco, cotton and cabbage. Earlier work in the 1980s and 1990s on populations from the same geographic locations indicated these hosts were on average ranked as high, mid and low preference plants, respectively, and that host rankings had a heritable component. In the present study, we found no change in the relative ranking of hosts by females, with most eggs being laid on tobacco, then cotton and least on cabbage. As in earlier work, some females laid most eggs on cotton and aspects of oviposition behaviour had a heritable component. Certainly, cotton is not avoided as a host, and the implications of these finding for managing resistance to Bt cotton are discussed.

DEVELOPMENT OF MOLECULAR MONITORING TECHNOLOGIES TO MEASURE TRANSGENE FLOW AND INTROGRESSION IN CROP AND NON-CROP PLANT SPECIES

Science.gov (United States)

The Gene Flow Project at the US Environmental Protection Agency, Western Ecology Division is developing methodologies for ecological risk assessments of transgene flow using Agrostis and Brassica engineered with CP4 EPSPS genes that confer resistance to glyphosate herbicide. In ...

The spinosyn family of insecticides: realizing the potential of natural products research.

Science.gov (United States)

Kirst, Herbert A

2010-03-01

The spinosyns are a large family of unprecedented compounds produced from fermentation of two species of Saccharopolyspora. Their core structure is a polyketide-derived tetracyclic macrolide appended with two saccharides. They show potent insecticidal activities against many commercially significant species that cause extensive damage to crops and other plants. They also show activity against important external parasites of livestock, companion animals and humans. Spinosad is a defined combination of the two principal fermentation factors, spinosyns A and D. Structure-activity relationships (SARs) have been extensively studied, leading to development of a semisynthetic second-generation derivative, spinetoram. The spinosyns have a unique mechanism of action (MOA) involving disruption of nicotinic acetylcholine receptors. When compared with many other insecticides, the spinosyns generally show greater selectivity toward target insects and lesser activity against many beneficial predators as well as mammals and other aquatic and avian animals. Their insecticidal spectrum, unique MOA and lower environmental effect make them useful new agents for modern integrated pest management programs. As a result, this work has received U S Presidential Green Chemistry Challenge Awards.

Modifying Bananas: From Transgenics to Organics?

Directory of Open Access Journals (Sweden)

James Dale

2017-02-01

Full Text Available Bananas are one of the top ten world food crops. Unlike most other major food crops, bananas are difficult to genetically improve. The challenge is that nearly all banana cultivars and landraces are triploids, with high levels of male and female infertility. There are a number of international conventional breeding programs and many of these are developing new cultivars. However, it is virtually impossible to backcross bananas, thus excluding the possibility of introgressing new traits into a current cultivar. The alternative strategy is to “modify” the cultivar itself. We have been developing the capacity to modify Cavendish bananas and other cultivars for both disease resistance and enhanced fruit quality. Initially, we were using transgenes; genes that were derived from species outside of the Musa or banana genus. However, we have recently incorporated two banana genes (cisgenes into Cavendish; one to enhance the level of pro-vitamin A and the other to increase the resistance to Panama disease. Modified Cavendish with these cisgenes have been employed in a field trial. Almost certainly, the next advance will be to edit the Cavendish genome, to generate the desired traits. As these banana cultivars are essentially sterile, transgene flow and the outcrossing of modified genes into wild Musa species. are highly unlikely and virtually impossible in other triploid cultivars. Therefore, genetic changes in bananas may be compatible with organic farming.

Experience with environmental issues in GM crop production and the likely future scenarios.

Science.gov (United States)

Gaugitsch, Helmut

2002-02-28

In the Cartagena Protocol on Biosafety, standards for risk assessment of genetically modified organisms (GMOs) have been set. The criteria and information basis for the risk assessment of GMOs have been modified by the EU Directive 2001/18/EC. Various approaches to further improve the criteria for environmental risk assessment of GMOs are described in this study. Reports on the ecological impacts of the cultivation of certain non-transgenic crop plants with novel or improved traits as analogy models to transgenic plants showed that the effects of agricultural practice can be at least equally important as the effects of gene transfer and invasiveness, although the latter currently play a major role in risk assessment of transgenic crops. Based on these results the applicability of the methodology of 'Life Cycle Analysis (LCA)' for genetically modified plants in comparison with conventionally bred and organically grown crop plants was evaluated. The methodology was regarded as applicable with some necessary future improvements. In current projects, the assessment of toxicology and allergenicity of GM crops are analysed, and suggestions for standardization are developed. Based on results and recommendations from these efforts there are still the challenges of how to operationalize the precautionary principle and how to take into account ecologically sensitive ecosystems, including centres of origin and centres of genetic diversity.

Impact of insecticides on parasitoids of the leafminer, Liriomyza trifolii, in pepper in south Texas.

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Hernández, Ricardo; Harris, Marvin; Liu, Tong-Xian

2011-01-01

Liriomyza leafminers (Diptera: Agromyzidae) are cosmopolitan, polyphagous pests of horticultural plants and many are resistant to insecticides. Producers in South Texas rely on insecticides as the primary management tool for leafminers, and several compounds are available. The objective of this study is to address the efficacy of these compounds for controlling Liriomyza while minimizing their effects against natural enemies. Research plots were established at Texas AgriLife research center at Weslaco, Texas in fall 2007 and spring 2008 seasons, and peppers were used as a model crop. Plots were sprayed with novaluron, abamectin, spinetoram, lambda-cyhalothrin and water as treatments according to leafminer infestation; insecticide efficacy was monitored by collecting leaves and infested foliage. Plant phenology was also monitored. Novaluron was the most effective insecticide and lambda-cyhalothrin showed resurgence in leafminer density in fall 2007 and no reduction in spring 2008. Other compounds varied in efficacy. Novaluron showed the least number of parasitoids per leafminer larva and the lowest parasitoid diversity index among treatments followed by spinetoram. Liriomyza trifolii (Burgess) was the sole leafminer species on peppers, and 19 parasitoid species were found associated with this leafminer. Application of these insecticides for management of leafminers with conservation of natural enemies is discussed.

Cell suspension culture-mediated incorporation of the rice bel gene into transgenic cotton.

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Liping Ke

Full Text Available Cotton plants engineered for resistance to the herbicides, glyphosate or glufosinate have made a considerable impact on the production of the crop worldwide. In this work, embryogenic cell cultures derived from Gossypium hirsutum L. cv Coker 312 hypocotyl callus were transformed via Agrobacterium tumefaciens with the rice cytochrome P450 gene, CYP81A6 (bel. In rice, bel has been shown to confer resistance to both bentazon and sulfanylurea herbicides. Transformed cells were selected on a liquid medium supplemented alternately or simultaneously with kanamycin (50mg/L and bentazon (4.2 µmol. A total of 17 transgenic cotton lines were recovered, based on the initial resistance to bentazon and on PCR detection of the bel transgene. Bel integration into the cotton genome was confirmed by Southern blot and expression of the transgene was verified by RT-PCR. In greenhouse and experimental plot trials, herbicide (bentazon tolerance of up to 1250 mg/L was demonstrated in the transgenic plants. Transgenic lines with a single copy of the bel gene showed normal Mendelian inheritance of the characteristic. Importantly, resistance to bentazon was shown to be stably incorporated in the T1, T2 and T3 generations of self-fertilised descendents and in plants outcrossed to another upland cotton cultivar. Engineering resistance to bentazon in cotton through the heterologous expression of bel opens the possibility of incorporating this trait into elite cultivars, a strategy that would give growers a more flexible alternative to weed management in cotton crops.

Residual Acute Toxicity of Some Modern Insecticides Toward Two Mirid Predators of Tomato Pests.

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Wanumen, Andrea C; Carvalho, Geraldo A; Medina, Pilar; Viñuela, Elisa; Adán, Ángeles

2016-03-31

The successful integration of chemical and biological control strategies for crop pests depends on a thorough evaluation of the effects of pesticides on the natural enemies of pests. A case-by-case review is difficult to achieve because of the many combinations of pests, natural enemies, and crops that need to be tested. Within this framework, we tested and compared seven insecticides representative of four different modes of action (MoAs) groups on closely related predators (Miridae): flubendiamide, spirotetramat, metaflumizone, and sulfoxaflor onNesidiocoris tenuisReuter and flubendiamide, spiromesifen, indoxacarb, and imidacloprid onMacrolophus basicornis(Stal). We follow the standardized methodology of the International Organization for Biological Control, a sequential testing exposure scheme. The lethal effect of each insecticide was evaluated in adults after three days of contact with treated surfaces in the laboratory, extended laboratory, and semifield tests (inert substrate, tomato leaves, and tomato plant as the treated surface, respectively). Flubendiamide, spiromesifen, and spirotetramat were classified as harmless (class 1), metaflumizone was slightly harmful (class 2) but persistent, indoxacarb was harmless (class 1), and sulfoxaflor and imidacloprid were toxic (class 4) and exhibited a long residual activity. Our results suggest similarities in the acute toxicities of insecticides from the same MoA group on related species of natural enemies. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Low crop plant population densities promote pollen-mediated gene flow in spring wheat (Triticum aestivum L.).

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Willenborg, Christian J; Brûlé-Babel, Anita L; Van Acker, Rene C

2009-12-01

Transgenic wheat is currently being field tested with the intent of eventual commercialization. The development of wheat genotypes with novel traits has raised concerns regarding the presence of volunteer wheat populations and the role they may play in facilitating transgene movement. Here, we report the results of a field experiment that investigated the potential of spring wheat plant population density and crop height to minimize gene flow from a herbicide-resistant (HR) volunteer population to a non-HR crop. Pollen-mediated gene flow (PMGF) between the HR volunteer wheat population and four conventional spring wheat genotypes varying in height was assessed over a range of plant population densities. Natural hybridization events between the two cultivars were detected by phenotypically scoring plants in F(1) populations followed by verification with Mendelian segregation ratios in the F(1:2) families. PMGF was strongly associated with crop yield components, but showed no association with flowering synchrony. Maximum observed PMGF was always less than 0.6%, regardless of crop height and density. The frequency of PMGF in spring wheat decreased exponentially with increasing plant population density, but showed no dependence on either crop genotype or height. However, increasing plant densities beyond the recommended planting rate of 300 cropped wheat plants m(-2) provided no obvious benefit to reducing PMGF. Nevertheless, our results demonstrate a critical plant density of 175-200 cropped wheat plants m(-2) below which PMGF frequencies rise exponentially with decreasing plant density. These results will be useful in the development of mechanistic models and best management practices that collectively facilitate the coexistence of transgenic and nontransgenic wheat crops.

Gene Flow in Genetically Engineered Perennial Grasses: Lessons for Modification of Dedicated Bioenergy Crops

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Genetic modification of dedicated bioenergy crops, such as switchgrass, will play a major role in crop improvement for a wide range of beneficial traits specific to biofuels. One obstacle that arises regarding transgenic improvement of perennials used for biofuels is the propensity of these plants t...

Pollen Competition as a Reproductive Isolation Barrier Represses Transgene Flow between Compatible and Co-Flowering Citrus Genotypes

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Pons, Elsa; Navarro, Antonio; Ollitrault, Patrick; Peña, Leandro

2011-01-01

Background/Objective Despite potential benefits granted by genetically modified (GM) fruit trees, their release and commercialization raises concerns about their potential environmental impact, and the transfer via pollen of transgenes to cross-compatible cultivars is deemed to be the greatest source for environmental exposure. Information compiled from field trials on GM trees is essential to propose measures to minimize the transgene dispersal. We have conducted a field trial of seven consecutive years to investigate the maximum frequency of pollen-mediated crop-to-crop transgene flow in a citrus orchard, and its relation to the genetic, phenological and environmental factors involved. Methodology/Principal Findings Three different citrus genotypes carrying the uidA (GUS) tracer marker gene (pollen donors) and a non-GM self-incompatible contiguous citrus genotype (recipient) were used in conditions allowing natural entomophilous pollination to occur. The examination of 603 to 2990 seeds per year showed unexpectedly low frequencies (0.17–2.86%) of transgene flow. Paternity analyses of the progeny of subsets of recipient plants using 10 microsatellite (SSR) loci demonstrated a higher mating competence of trees from another non-GM pollen source population that greatly limited the mating chance of the contiguous cross-compatible and flowering-synchronized transgenic pollen source. This mating superiority could be explained by a much higher pollen competition capacity of the non-GM genotypes, as was confirmed through mixed-hand pollinations. Conclusions/Significance Pollen competition strongly contributed to transgene confinement. Based on this finding, suitable isolation measures are proposed for the first time to prevent transgene outflow between contiguous plantings of citrus types that may be extendible to other entomophilous transgenic fruit tree species. PMID:21991359

Systemic insecticides (neonicotinoids and fipronil): trends, uses, mode of action and metabolites

OpenAIRE

Simon-Delso, N.; Amaral-Rogers, V.; Belzunces, L. P.; Bonmatin, J. M.; Chagnon, M.; Downs, C.; Furlan, L.; Gibbons, D. W.; Giorio, C.; Girolami, V.; Goulson, D.; Kreutzweiser, D. P.; Krupke, C. H.; Liess, M.; Long, E.

2014-01-01

Since their discovery in the late 1980s, neonicotinoid pesticides have become the most widely used class of insecticides worldwide, with large-scale applications ranging from plant protection (crops, vegetables, fruits), veterinary products, and biocides to invertebrate pest control in fish farming. In this review, we address the phenyl-pyrazole fipronil together with neonicotinoids because of similarities in their toxicity, physicochemical profiles, and presence in the environment. Neonicoti...

Development of transgenic watermelon resistant to Cucumber mosaic virus and Watermelon mosaic virus by using a single chimeric transgene construct.

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Lin, Ching-Yi; Ku, Hsin-Mei; Chiang, Yi-Hua; Ho, Hsiu-Yin; Yu, Tsong-Ann; Jan, Fuh-Jyh

2012-10-01

Watermelon, an important fruit crop worldwide, is prone to attack by several viruses that often results in destructive yield loss. To develop a transgenic watermelon resistant to multiple virus infection, a single chimeric transgene comprising a silencer DNA from the partial N gene of Watermelon silver mottle virus (WSMoV) fused to the partial coat protein (CP) gene sequences of Cucumber mosaic virus (CMV), Cucumber green mottle mosaic virus (CGMMV) and Watermelon mosaic virus (WMV) was constructed and transformed into watermelon (cv. Feeling) via Agrobacterium-mediated transformation. Single or multiple transgene copies randomly inserted into various locations in the genome were confirmed by Southern blot analysis. Transgenic watermelon R(0) plants were individually challenged with CMV, CGMMV or WMV, or with a mixture of these three viruses for resistance evaluation. Two lines were identified to exhibit resistance to CMV, CGMMV, WMV individually, and a mixed inoculation of the three viruses. The R(1) progeny of the two resistant R(0) lines showed resistance to CMV and WMV, but not to CGMMV. Low level accumulation of transgene transcripts in resistant plants and small interfering (si) RNAs specific to CMV and WMV were readily detected in the resistant R(1) plants by northern blot analysis, indicating that the resistance was established via RNA-mediated post-transcriptional gene silencing (PTGS). Loss of the CGMMV CP-transgene fragment in R1 progeny might be the reason for the failure to resistant CGMMV infection, as shown by the absence of a hybridization signal and no detectable siRNA specific to CGMMV in Southern and northern blot analyses. In summary, this study demonstrated that fusion of different viral CP gene fragments in transgenic watermelon contributed to multiple virus resistance via PTGS. The construct and resistant watermelon lines developed in this study could be used in a watermelon breeding program for resistance to multiple viruses.

Metabolism of methoxychlor by the P450-monooxygenase CYP6G1 involved in insecticide resistance of Drosophila melanogaster after expression in cell cultures of Nicotiana tabacum.

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Joussen, Nicole; Schuphan, Ingolf; Schmidt, Burkhard

2010-03-01

Cytochrome P450 monooxygenase CYP6G1 of Drosophila melanogaster was heterologously expressed in a cell suspension culture of Nicotiana tabacum. This in vitro system was used to study the capability of CYP6G1 to metabolize the insecticide methoxychlor (=1,1,1-trichloro-2,2-bis(4-methoxyphenyl)ethane, 1) against the background of endogenous enzymes of the corresponding non-transgenic culture. The Cyp6g1-transgenic cell culture metabolized 96% of applied methoxychlor (45.8 microg per assay) within 24 h by demethylation and hydroxylation mainly to trishydroxy and catechol methoxychlor (16 and 17%, resp.). About 34% of the metabolism and the distinct formation of trishydroxy and catechol methoxychlor were due to foreign enzyme CYP6G1. Furthermore, methoxychlor metabolism was inhibited by 43% after simultaneous addition of piperonyl butoxide (458 microg), whereas inhibition in the non-transgenic culture amounted to 92%. Additionally, the rate of glycosylation was reduced in both cultures. These results were supported by the inhibition of the metabolism of the insecticide imidacloprid (6; 20 microg, 24 h) in the Cyp6g1-transgenic culture by 82% in the presence of piperonyl butoxide (200 microg). Due to CYP6G1 being responsible for imidacloprid resistance of Drosophila or being involved in DDT resistance, it is likely that CYP6G1 conveys resistance to methoxychlor (1). Furthermore, treating Drosophila with piperonyl butoxide could weaken the observed resistance phenomena.

The contribution of agricultural insecticide use to increasing insecticide resistance in African malaria vectors

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Reid, Molly C.; McKenzie, F. Ellis

2016-01-01

The fight against malaria is increasingly threatened by failures in vector control due to growing insecticide resistance. This review examines the recent primary research that addresses the putative relationship between agricultural insecticide use and trends in insecticide resistance. To do so, descriptive evidence offered by the new research was categorized, and additional factors that impact the relationship between agricultural insecticide use and observed insecticide resistance in malari...

Lethality of reduced-risk insecticides against plum curculio (Coleoptera: Curculionidae) in blueberries with emphasis on their curative activity

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Ongoing regulatory changes are eliminating or restricting the use of broad-spectrum insecticides in fruit crops in the USA, and current IPM programs for plum curculio, Conotrachelus nenuphar (Herbst), in highbush blueberries, Vaccinium corymbosum L, need to address these changes. To assist in this ...

Physiological selectivity and activity reduction of insecticides by rainfall to predatory wasps of Tuta absoluta.

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Barros, Emerson C; Bacci, Leandro; Picanco, Marcelo C; Martins, Júlio C; Rosado, Jander F; Silva, Gerson A

2015-01-01

In this study, we carried out three bioassays with nine used insecticides in tomato crops to identify their efficiency against tomato leaf miner Tuta absoluta, the physiological selectivity and the activity reduction of insecticides by three rain regimes to predatory wasps Protonectarina sylveirae and Polybia scutellaris. We assessed the mortality caused by the recommended doses of abamectin, beta-cyfluthrin, cartap, chlorfenapyr, etofenprox, methamidophos, permethrin, phenthoate and spinosad to T. absoluta and wasps at the moment of application. In addition, we evaluated the wasp mortality due to the insecticides for 30 days on plants that did not receive rain and on plants that received 4 or 125 mm of rain. Spinosad, cartap, chlorfenapyr, phenthoate, abamectin and methamidophos caused mortality higher than 90% to T. absoluta, whereas the pyrethroids beta-cyfluthrin, etofenprox and permethrin caused mortality between 8.5% and 46.25%. At the moment of application, all the insecticides were highly toxic to the wasps, causing mortality higher than 80%. In the absence of rain, all the insecticides continued to cause high mortality to the wasps for 30 days after the application. The toxicity of spinosad and methamidophos on both wasp species; beta-cyfluthrin on P. sylveirae and chlorfenapyr and abamectin on P. scutellaris, decreased when the plants received 4 mm of rain. In contrast, the other insecticides only showed reduced toxicity on the wasps when the plants received 125 mm of rain.

Hybridization between crops and wild relatives: the contribution of cultivated lettuce to the vigour of crop–wild hybrids under drought, salinity and nutrient deficiency conditions

OpenAIRE

Uwimana, Brigitte; Smulders, Marinus J.M.; Hooftman, Danny A.P.; Hartman, Yorike; van Tienderen, Peter H.; Jansen, Johannes; McHale, Leah K.; Michelmore, Richard W.; van de Wiel , Clemens C.M.; Visser , Richard G.F.

2012-01-01

With the development of transgenic crop varieties, crop–wild hybridization has received considerable consideration with regard to the potential of transgenes to be transferred to wild species. Although many studies have shown that crops can hybridize with their wild relatives and that the resulting hybrids may show improved fitness over the wild parents, little is still known on the genetic contribution of the crop parent to the performance of the hybrids. In this study, we investigated the v...

Transgenic rice plants expressing synthetic cry2AX1 gene exhibits resistance to rice leaffolder (Cnaphalocrosis medinalis).

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Manikandan, R; Balakrishnan, N; Sudhakar, D; Udayasuriyan, V

2016-06-01

Bacillus thuringiensis is a major source of insecticidal genes imparting insect resistance in transgenic plants. Level of expression of transgenes in transgenic plants is important to achieve desirable level of resistance against target insects. In order to achieve desirable level of expression, rice chloroplast transit peptide sequence was fused with synthetic cry2AX1 gene to target its protein in chloroplasts. Sixteen PCR positive lines of rice were generated by Agrobacterium mediated transformation using immature embryos. Southern blot hybridization analysis of T 0 transgenic plants confirmed the integration of cry2AX1 gene in two to five locations of rice genome and ELISA demonstrated its expression. Concentration of Cry2AX1 in transgenic rice events ranged 5.0-120 ng/g of fresh leaf tissue. Insect bioassay of T 0 transgenic rice plants against neonate larvae of rice leaffolder showed larval mortality ranging between 20 and 80 % in comparison to control plant. Stable inheritance and expression of cry2AX1 gene was demonstrated in T 1 progenies through Southern and ELISA. In T 1 progenies, the highest concentration of Cry2AX1 and mortality of rice leaffolder larvae were recorded as 150 ng/g of fresh leaf tissue and 80 %, respectively. The Cry2AX1 expression even at a very low concentration (120-150 ng/g) in transgenic rice plants was found effective against rice leaffolder larvae.

Bt crop effects on functional guilds of non-target arthropods: A meta-analysis (journal)

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Background: Uncertainty persists over the environmental effects of genetically-engineered crops that produce the insecticidal Cry proteins of Bacillus thuringiensis (Bt). We performed meta-analyses on a modified public database to synthesize current knowledge about the effects of...

A wheat calreticulin gene (TaCRT1) contributes to drought tolerance in transgenic arabidopsis

International Nuclear Information System (INIS)

Xiang, V.; Du, C.; Jia, H.; Song, M.; Wang, Y.; Ma, Z.

2018-01-01

The TaCRT1 gene is a member of calreticulin (CRT) family in wheat. In our previous study, we showed that transgenic tobacco lines over expressing wheat TaCRT1 showed enhanced tolerance to salt stress. This study aimed to determine whether TaCRT1 over expression would increase drought tolerance in transgenic Arabidopsis. Over expression of TaCRT1 in Arabidopsis plants enhances tolerance to drought stress. However, the transgenic line was found to retard the growth. Moreover, the transgenic line showed decreased water loss but higher sensitivity to exogenous abscisic acid (ABA) compared with the wild type (Col-0). Meanwhile, the transgenic line had the elevated endogenous ABA level. The semi-quantitative RT-PCR (sqRT-PCR) analysis showed that transcription levels of ABA-biosynthesizing gene (NCED3) and ABA-responsive gene (ABF3) were higher in the transgenic line than that in the Col-0 under normal condition. The above results implied that the TaCRT1 might be able to used as a potential target to improve the drought tolerance in crops. (author)

Selectivity of pesticides used in rice crop on Telenomus podisi and Trichogramma pretiosum

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Juliano de Bastos Pazini

2016-09-01

Full Text Available Telenomus and Trichogramma species stand out as agents for the biological control in rice crops, and the main strategy for preserving them is the use of selective pesticides. This study aimed at evaluating the toxicity of pesticides used in irrigated rice crop on Telenomus podisi Ashmead (Hymenoptera: Platygastridae and Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae. Adults of these parasitoids were exposed to dry residues of pesticides, in a completely randomized experiment, with 25 treatments (24 pesticides + control and four replications. The insecticides clorantraniliprole, flubendiamide and diflubenzuron and the biological insecticides based on Beauveria bassiana and Metarhizium anisopliae were harmless to T. podisi and T. pretiosum. The harmless herbicides were: 2.4-D amine, profoxydim, quinclorac, ethoxysulfuron and saflufenacil. The fungicide epoxiconazole + kresoxim-methyl was also harmless to these two biological control agents. Therefore, these pesticides are indicated for the integrated pest management, in flooded rice areas.

Characterization of UDP-glucuronosyltransferase genes and their possible roles in multi-insecticide resistance in Plutella xylostella (L.).

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Li, Xiuxia; Shi, Haiyan; Gao, Xiwu; Liang, Pei

2018-03-01

Uridine diphosphate-glucuronosyltransferases (UGTs), as multifunctional detoxification enzymes, play important roles in the biotransformation of various compounds. However, their roles in insecticide resistance are still unclear. This study presents a genome-wide identification of the UGTs in diamondback moth, Plutella xylostella (L.), a notorious insect pest of cruciferous crops worldwide. The possible roles of these UGTs in insecticide resistance were evaluated. A total of 21 putative UGTs in P. xylostella were identified. Quantitative real-time polymerase chain reaction (PCR)-based analyses showed that all the UGT genes were expressed in all tested developmental stages and tissues. Bioassay results indicated that a field-collected population (BL) was resistant to 9 of 10 commonly used insecticides, and 10 of 21 UGT mRNAs were upregulated in the BL population. Exposure to the LC 50 of each insecticide affected the expression of most UGT genes. Among these, the expression levels of UGT40V1, UGT45B1 and UGT33AA4 were induced by more than five insecticides, whereas indoxacarb and metaflumizone significantly repressed the expression of most UGT genes. UGTs may play important roles in the metabolism of commonly used insecticides in P. xylostella. These findings provide valuable information for further research on the physiological and toxicological functions of specific UGT genes in P. xylostella. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

In-silico determination of insecticidal potential of Vip3Aa-Cry1Ac fusion protein against Lepidopteran targets using molecular docking

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Aftab eAhmad

2015-12-01

Full Text Available Study and research of Bt (Bacillus thuringiensis transgenic plants have opened new ways to combat insect pests. Over the decades, however, insect pests, especially the Lepidopteran, have developed tolerance against Bt delta-endotoxins. Such issues can be addressed through the development of novel toxins with greater toxicity and affinity against a broad range of insect receptors. In this computational study, functional domains of Bacillus thuringiensis crystal delta-endotoxin (Cry1Ac insecticidal protein and vegetative insecticidal protein (Vip3Aa have been fused to develop a broad-range Vip3Aa-Cry1Ac fusion protein. Cry1Ac and Vip3Aa are non-homologous insecticidal proteins possessing receptors against different targets within the midgut of insects. The insecticidal proteins were fused to broaden the insecticidal activity. Molecular docking analysis of the fusion protein against aminopeptidase-N (APN and cadherin receptors of five Lepidopteran insects (Agrotis ipsilon, Helicoverpa armigera, Pectinophora gossypiella, Spodoptera exigua and Spodoptera litura revealed that the Ser290, Ser293, Leu337, Thr340 and Arg437 residues of the fusion protein are involved in the interaction with insect receptors. The Helicoverpa armigera cadherin receptor, however, showed no interaction, which might be due to either loss or burial of interactive residues inside the fusion protein. These findings revealed that the Vip3Aa-Cry1Ac fusion protein has a strong affinity against Lepidopteran insect receptors and hence has a potential to be an efficient broad-range insecticidal protein.

Attitudes in China about Crops and Foods Developed by Biotechnology

OpenAIRE

Han, Fei; Zhou, Dingyang; Liu, Xiaoxia; Cheng, Jie; Zhang, Qingwen; Shelton, Anthony M.

2015-01-01

Transgenic Bt cotton has been planted in China since 1997 and, in 2009, biosafety certificates for the commercial production of Bt rice and phytase corn were issued by the Chinese government. The public attitude in China toward agricultural biotechnology and genetically modified (GM) crops and foods has received considerable attention worldwide. We investigated the attitudes of consumers, Bt cotton farmers and scientists in China regarding GM crops and foods and the factors influencing their ...

THE ROLE OF SPECTRAL IMAGERY FOR MONITORING & MODELING TRANSGENIC CROP-PEST INTERACTIONS

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Crops bioengineered to contain toxins derived from Bacillus thuringensis (Bt) are under regulatory scrutiny by USEPA under the FIFRA legislation. The agency has declared these crops to be "in the public good" based on the reduced use of pesticides required for management of these...

A short history of insecticides

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Oberemok Volodymyr Volodymyrovych

2015-07-01

Full Text Available This review contains a brief history of the use of insecticides. The peculiarities, main advantages, and disadvantages of some modern insecticides are described. The names of the discoverers of some of the most popular insecticide preparations on the world market, are listed. The tendencies to find new insecticides to control the quantity of phytophagous insects are discussed. Special attention is paid to the perspective of creating preparations based on nucleic acids, in particular DNA insecticides. The use of insect-specific, short single-stranded DNA fragments as DNA insecticides, is paving the way in the field of “intellectual” insecticides that “think” before they act. It is worth noting, though, that in the near future, the quantity of produced insecticides will increase due to the challenges associated with food production for a rapidly growing population. It is concluded, that an agreeable interaction of scientists and manufacturers of insecticides should lead to the selection of the most optimal solutions for insect pest control, which would be safe, affordable, and effective at the same time.

Genetically modified crops: Brazilian law and overview.

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Marinho, C D; Martins, F J O; Amaral Júnior, A T; Gonçalves, L S A; dos Santos, O J A P; Alves, D P; Brasileiro, B P; Peternelli, L A

2014-07-07

In Brazil, the first genetically modified (GM) crop was released in 1998, and it is estimated that 84, 78, and 50% of crop areas containing soybean, corn, and cotton, respectively, were transgenic in 2012. This intense and rapid adoption rate confirms that the choice to use technology has been the main factor in developing national agriculture. Thus, this review focuses on understanding these dynamics in the context of farmers, trade relations, and legislation. To accomplish this goal, a survey was conducted using the database of the National Cultivar Registry and the National Service for Plant Variety Protection of the Ministry of Agriculture, Livestock and Supply [Ministério da Agricultura, Pecuária e Abastecimento (MAPA)] between 1998 and October 13, 2013. To date, 36 events have been released: five for soybeans, 18 for corn, 12 for cotton, and one for beans. From these events, 1395 cultivars have been developed and registered: 582 for soybean, 783 for corn and 30 for cotton. Monsanto owns 73.05% of the technologies used to develop these cultivars, while the Dow AgroScience - DuPont partnership and Syngenta have 16.34 and 4.37% ownership, respectively. Thus, the provision of transgenic seeds by these companies is an oligopoly supported by legislation. Moreover, there has been a rapid replacement of conventional crops by GM crops, whose technologies belong almost exclusively to four multinational companies, with the major ownership by Monsanto. These results reflect a warning to the government of the increased dependence on multinational corporations for key agricultural commodities.

Development of transgenic wheat (Triticum aestivum L.) expressing avidin gene conferring resistance to stored product insects.

Science.gov (United States)

Abouseadaa, Heba H; Osman, Gamal H; Ramadan, Ahmed M; Hassanein, Sameh E; Abdelsattar, Mohamed T; Morsy, Yasser B; Alameldin, Hussien F; El-Ghareeb, Doaa K; Nour-Eldin, Hanan A; Salem, Reda; Gad, Adel A; Elkhodary, Soheir E; Shehata, Maher M; Mahfouz, Hala M; Eissa, Hala F; Bahieldin, Ahmed

2015-07-22

Wheat is considered the most important cereal crop all over the world. The wheat weevil Sitophilus granarius is a serious insect pests in much of the wheat growing area worldwide and is responsible for significant loss of yield. Avidin proteins has been proposed to function as plant defense agents against insect pests. A synthetic avidin gene was introduced into spring wheat (Triticum aestivum L.) cv. Giza 168 using a biolistic bombardment protocol. The presence and expression of the transgene in six selected T0 transgenic wheat lines were confirmed at the molecular level. Accumulation of avidin protein was detected in transgenic plants compared to non-transgenic plants. Avidin transgene was stably integrated, transcribed and translated as indicated by Southern blot, ELISA, and dot blot analyses, with a high level of expression in transgenic wheat seeds. However, no expression was detected in untransformed wheat seeds. Functional integrity of avidin was confirmed by insect bioassay. The results of bioassay using transgenic wheat plants challenged with wheat weevil revealed 100 % mortality of the insects reared on transgenic plants after 21 days. Transgenic wheat plants had improved resistance to Sitophilus granarius.

Public Acceptance of Plant Biotechnology and GM Crops

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Jan M. Lucht

2015-07-01

Full Text Available A wide gap exists between the rapid acceptance of genetically modified (GM crops for cultivation by farmers in many countries and in the global markets for food and feed, and the often-limited acceptance by consumers. This review contrasts the advances of practical applications of agricultural biotechnology with the divergent paths—also affecting the development of virus resistant transgenic crops—of political and regulatory frameworks for GM crops and food in different parts of the world. These have also shaped the different opinions of consumers. Important factors influencing consumer’s attitudes are the perception of risks and benefits, knowledge and trust, and personal values. Recent political and societal developments show a hardening of the negative environment for agricultural biotechnology in Europe, a growing discussion—including calls for labeling of GM food—in the USA, and a careful development in China towards a possible authorization of GM rice that takes the societal discussions into account. New breeding techniques address some consumers’ concerns with transgenic crops, but it is not clear yet how consumers’ attitudes towards them will develop. Discussions about agriculture would be more productive, if they would focus less on technologies, but on common aims and underlying values.

Public Acceptance of Plant Biotechnology and GM Crops

Science.gov (United States)

Lucht, Jan M.

2015-01-01

A wide gap exists between the rapid acceptance of genetically modified (GM) crops for cultivation by farmers in many countries and in the global markets for food and feed, and the often-limited acceptance by consumers. This review contrasts the advances of practical applications of agricultural biotechnology with the divergent paths—also affecting the development of virus resistant transgenic crops—of political and regulatory frameworks for GM crops and food in different parts of the world. These have also shaped the different opinions of consumers. Important factors influencing consumer’s attitudes are the perception of risks and benefits, knowledge and trust, and personal values. Recent political and societal developments show a hardening of the negative environment for agricultural biotechnology in Europe, a growing discussion—including calls for labeling of GM food—in the USA, and a careful development in China towards a possible authorization of GM rice that takes the societal discussions into account. New breeding techniques address some consumers’ concerns with transgenic crops, but it is not clear yet how consumers’ attitudes towards them will develop. Discussions about agriculture would be more productive, if they would focus less on technologies, but on common aims and underlying values. PMID:26264020

More than one rabbit out of the hat: Radiation, transgenic and symbiont-based approaches for sustainable management of mosquito and tsetse fly populations.

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Bourtzis, Kostas; Lees, Rosemary Susan; Hendrichs, Jorge; Vreysen, Marc J B

2016-05-01

Mosquitoes (Diptera: Culicidae) and tsetse flies (Diptera: Glossinidae) are bloodsucking vectors of human and animal pathogens. Mosquito-borne diseases (malaria, filariasis, dengue, zika, and chikungunya) cause severe mortality and morbidity annually, and tsetse fly-borne diseases (African trypanosomes causing sleeping sickness in humans and nagana in livestock) cost Sub-Saharan Africa an estimated US$ 4750 million annually. Current reliance on insecticides for vector control is unsustainable: due to increasing insecticide resistance and growing concerns about health and environmental impacts of chemical control there is a growing need for novel, effective and safe biologically-based methods that are more sustainable. The integration of the sterile insect technique has proven successful to manage crop pests and disease vectors, particularly tsetse flies, and is likely to prove effective against mosquito vectors, particularly once sex-separation methods are improved. Transgenic and symbiont-based approaches are in development, and more advanced in (particularly Aedes) mosquitoes than in tsetse flies; however, issues around stability, sustainability and biosecurity have to be addressed, especially when considering population replacement approaches. Regulatory issues and those relating to intellectual property and economic cost of application must also be overcome. Standardised methods to assess insect quality are required to compare and predict efficacy of the different approaches. Different combinations of these three approaches could be integrated to maximise their benefits, and all have the potential to be used in tsetse and mosquito area-wide integrated pest management programmes. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Untranslatable tospoviral NSs fragment coupled with L conserved region enhances transgenic resistance against the homologous virus and a serologically unrelated tospovirus.

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Yazhisai, Uthaman; Rajagopalan, Prem Anand; Raja, Joseph A J; Chen, Tsung-Chi; Yeh, Shyi-Dong

2015-08-01

Tospoviruses cause severe damages to important crops worldwide. In this study, Nicotiana benthamiana transgenic lines carrying individual untranslatable constructs comprised of the conserved region of the L gene (denoted as L), the 5' half of NSs coding sequence (NSs) or the antisense fragment of whole N coding sequence (N) of Watermelon silver mottle virus (WSMoV), individually or in combination, were generated. A total of 15-17 transgenic N. benthamiana lines carrying individual transgenes were evaluated against WSMoV and the serologically unrelated Tomato spotted wilt virus (TSWV). Among lines carrying single or chimeric transgenes, the level of resistance ranged from susceptible to completely resistant against WSMoV. From the lines carrying individual transgenes and highly resistant to WSMoV (56-63% of lines assayed), 30% of the L lines (3/10 lines assayed) and 11% of NSs lines (1/9 lines assayed) were highly resistant against TSWV. The chimeric transgenes provided higher degrees of resistance against WSMoV (80-88%), and the NSs fragment showed an additive effect to enhance the resistance to TSWV. Particularly, the chimeric transgenes with the triple combination of fragments, namely L/NSs/N or HpL/NSs/N (a hairpin construct), provided a higher degree of resistance (both 50%, with 7/14 lines assayed) against TSWV. Our results indicate that the untranslatable NSs fragment is able to enhance the transgenic resistance conferred by the L conserved region. The better performance of L/NSs/N and HpL/NSs/N in transgenic N. benthamiana lines suggests their potential usefulness in generating high levels of enhanced transgenic resistance against serologically unrelated tospoviruses in agronomic crops.

Comparison of herbicide regimes and the associated potential enviromental effects of glyphosate-resistant crops versus what they replace in Europe

NARCIS (Netherlands)

Kleter, G.A.; Harris, C.; Stephenson, G.R.; Unsworth, J.

2008-01-01

While cultivation of transgenic crops takes place in seven of the EU member states, this constitutes a relatively limited part of the total acreage planted to these crops worldwide. The only glyphosate-resistant (GR) crop grown commercially until recently has been soybean in Romania. In addition,

Transgenic tobacco plants constitutively expressing peanut BTF3 exhibit increased growth and tolerance to abiotic stresses.

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Pruthvi, V; Rama, N; Parvathi, M S; Nataraja, K N

2017-05-01

Abiotic stresses limit crop growth and productivity worldwide. Cellular tolerance, an important abiotic stress adaptive trait, involves coordinated activities of multiple proteins linked to signalling cascades, transcriptional regulation and other diverse processes. Basal transcriptional machinery is considered to be critical for maintaining transcription under stressful conditions. From this context, discovery of novel basal transcription regulators from stress adapted crops like peanut would be useful for improving tolerance of sensitive plant types. In this study, we prospected a basal transcription factor, BTF3 from peanut (Arachis hypogaea L) and studied its relevance in stress acclimation by over expression in tobacco. AhBTF3 was induced under PEG-, NaCl-, and methyl viologen-induced stresses in peanut. The constitutive expression of AhBTF3 in tobacco increased plant growth under non stress condition. The transgenic plants exhibited superior phenotype compared to wild type under mannitol- and NaCl-induced stresses at seedling level. The enhanced cellular tolerance of transgenic plants was evidenced by higher cell membrane stability, reactive oxygen species (ROS) scavenging activity, seedling survival and vigour than wild type. The transgenic lines showed better in vitro regeneration capacity on growth media supplemented with NaCl than wild type. Superior phenotype of transgenic plants under osmotic and salinity stresses seems to be due to constitutive activation of genes of multiple pathways linked to growth and stress adaptation. The study demonstrated that AhBTF3 is a positive regulator of growth and stress acclimation and hence can be considered as a potential candidate gene for crop improvement towards stress adaptation. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

Toxicity of nine insecticides on four natural enemies of Spodoptera exigua

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Liu, Yongqiang; Li, Xiangying; Zhou, Chao; Liu, Feng; Mu, Wei

2016-01-01

Spodoptera exigua, which feeds on various crops worldwide, has natural enemies that are susceptible to the insecticides used against S. exigua. We investigate the toxicity and residue risk of 9 insecticides on the development of H. axyridis, C. sinica, S. manilae and T. remus. S. manilae and T. remus adults were sensitive to all 9 insecticides (LC50 less than 2.75 mg a.i. liter−1), while H. axyridis and C. sinica adults were less sensitive (LC50 between 6 × 10−5 mg a.i. liter−1 and 78.95 mg a.i. liter−1). Emamectin benzoate, spinosad, indoxacarb, alpha-cypermethrin, chlorfenapyr and chlorantraniliprole showed no toxicity on H. axyridis, C. sinica, S. manilae and T. remus pupae with the recommended field concentrations. The risk analysis indicated that chlorantraniliprole is harmless to larvae of four natural enemies and adult of H. axyridis, C. sinica and S. manilae. Emamectin benzoate and spinosad had higher safety to the development of H. axyridis, C. sinica, S. manilae and T. remus with the risk duration less than 4d. Indoxacarb, tebufenozide, chlorfenapyr, methomyl, alpha-cypermethrin and chlorpyrifos showed dangerously toxic and long risk duration on S. manilae and T. remus adults. PMID:27958333

Toxicity of nine insecticides on four natural enemies of Spodoptera exigua.

Science.gov (United States)

Liu, Yongqiang; Li, Xiangying; Zhou, Chao; Liu, Feng; Mu, Wei

2016-12-13

Spodoptera exigua, which feeds on various crops worldwide, has natural enemies that are susceptible to the insecticides used against S. exigua. We investigate the toxicity and residue risk of 9 insecticides on the development of H. axyridis, C. sinica, S. manilae and T. remus. S. manilae and T. remus adults were sensitive to all 9 insecticides (LC 50 less than 2.75 mg a.i. liter -1 ), while H. axyridis and C. sinica adults were less sensitive (LC 50 between 6 × 10 -5  mg a.i. liter -1 and 78.95 mg a.i. liter -1 ). Emamectin benzoate, spinosad, indoxacarb, alpha-cypermethrin, chlorfenapyr and chlorantraniliprole showed no toxicity on H. axyridis, C. sinica, S. manilae and T. remus pupae with the recommended field concentrations. The risk analysis indicated that chlorantraniliprole is harmless to larvae of four natural enemies and adult of H. axyridis, C. sinica and S. manilae. Emamectin benzoate and spinosad had higher safety to the development of H. axyridis, C. sinica, S. manilae and T. remus with the risk duration less than 4d. Indoxacarb, tebufenozide, chlorfenapyr, methomyl, alpha-cypermethrin and chlorpyrifos showed dangerously toxic and long risk duration on S. manilae and T. remus adults.

Susceptibility of Aphelinus certus to foliar-applied insecticides currently or potentially registered for soybean aphid control.

Science.gov (United States)

Frewin, Andrew J; Schaafsma, Arthur W; Hallett, Rebecca H

2012-02-01

Soybean aphid, a serious economic pest of soybean in North America, is currently managed by applying non-selective foliar insecticides during outbreaks according to decision thresholds and crop maturity. Natural enemies, such as the parasitoid Aphelinus certus Yasnosh, potentially play an important role in suppressing soybean aphid. Using selective insecticides that preserve A. certus may enhance the biological control service they provide and thus prevent or reduce the severity of soybean aphid outbreaks. The toxicity of five insecticides (λ-cyhalothrin, dimethoate, flonicamid, mineral oil, spirotetramat) and the biopesticide Beauveria bassiana to A. certus was assessed. The LD50 values of λ-cyhalothrin and dimethoate were similar; however, the hazard quotient of dimethoate was greater than that of λ-cyhalothrin. In a screening bioassay, the descending order of toxicity for the recommended rates 48 h after application was dimethoate>λ-cyhalothrin>flonicamid>mineral oil>Beauveria bassiana>spirotetramat. Overall, λ-cyhalothrin and dimethoate were both harmful to A. certus. The other insecticides tested were harmless to A. certus and are potential candidates for inclusion in soybean aphid management programs. Copyright © 2011 Society of Chemical Industry.

Landscape and host plant effects on two important omnivorous arthropod taxa in field crops

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The economically important brown stink bug, Euschistus servus (Say), is a native pest of many crops in southeastern USA and insecticide applications are the prevailing method of population suppression. To elucidate biological control of E. servus populations, we investigated two egg predators’ (red ...

Adaptive mechanisms of insect pests against plant protease inhibitors and future prospects related to crop protection: a review.

Science.gov (United States)

Macedo, Maria L R; de Oliveira, Caio F R; Costa, Poliene M; Castelhano, Elaine C; Silva-Filho, Marcio C

2015-01-01

The overwhelming demand for food requires the application of technology on field. An important issue that limits the productivity of crops is related to insect attacks. Hence, several studies have evaluated the application of different compounds to reduce the field losses, especially insecticide compounds from plant sources. Among them, plant protease inhibitors (PIs) have been studied in both basic and applied researches, displaying positive results in control of some insects. However, certain species are able to bypass the insecticide effects exerted by PIs. In this review, we disclosed the adaptive mechanisms showed by lepidopteran and coleopteran insects, the most expressive insect orders related to crop predation. The structural aspects involved in adaptation mechanisms are presented as well as the newest alternatives for pest control. The application of biotechnological tools in crop protection will be mandatory in agriculture, and it will be up to researchers to find the best candidates for effective control in long-term.

Decrease of insecticide resistance over generations without exposure to insecticides in Nilaparvata lugens (Hemipteran: Delphacidae).

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Yang, Yajun; Dong, Biqin; Xu, Hongxing; Zheng, Xusong; Tian, Junce; Heong, Kongleun; Lu, Zhongxian

2014-08-01

The brown planthopper, Nilaparvata lugens (Stål), is one of the most important insect pests on paddy rice in tropical and temperate Asia. Overuse and misuse of insecticides have resulted in the development of high resistance to many different insecticides in this pest. Studies were conducted to evaluate the change of resistance level to four insecticides over 15 generations without any exposure to insecticides in brown planthopper. After 15 generations' rearing without exposure to insecticide, brown planthopper could reverse the resistance to imidacloprid, chlorpyrifos, fipronil, and fenobucarb. The range and style of resistance reversal of brown planthopper differed when treated with four different insecticides. To monitor potential changes in insect physiological responses, we measured the activity of each of the three selected enzymes, including acetylcholinesterases (AChE), general esterases (EST), and glutathione S-transferases. After multiple generations' rearing without exposure to insecticide, AChE and EST activities of brown planthopper declined with the increased generations, suggesting that the brown planthopper population adjusted activities of EST and AChE to adapt to the non-insecticide environment. These findings suggest that the reducing, temporary stop, or rotation of insecticide application could be incorporated into the brown planthopper management.

Emamectin benzoate: new insecticide against Helicoverpa armigera.

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Fanigliulo, A; Sacchetti, M

2008-01-01

Emamectin benzoate is a new insecticide of Syngenta Crop Protection, with a new mechanism of action and a strong activity against Lepidoptera as well as with and a high selectivity on useful organisms. This molecule acts if swallowed and has some contact action. It penetrates leaf tissues (translaminar activity) and forms a reservoir within the leaf. The mechanism of action is unique in the panorama of insecticides. In facts, it inhibits muscle contraction, causing a continuous flow of chlorine ions in the GABA and H-Glutamate receptor sites. During 2006 and 2007, experimentation was performed by the Bioagritest test facility, according to EPPO guidelines and Principles of Good Experimental Practice (GEP), aiming at establishing the biological efficacy and the selectivity of Emamectin benzoate on industry tomato against Helicoverpa armigera (Lepidoptera: Noctuidoe). The study was performed in Tursi-Policoro (Matera), southern Italy. Experimental design consisted in random blocks, in 4 repetitions. A dosage of 1.5 Kg/ha of the formulate was compared with two commercial formulates: Spinosad 0.2 kg/ha (Laser, Dow Agrosciences Italia) and Indoxacarb 0.125 kg/ha (Steward EC insecticide, Dupont). Three foliage applications were applied every 8 days. The severity of damage induced by H. armigera was evaluated on fruits. Eventual phytotoxic effects were also evaluated. Climatic conditions were optimal for Lepidoptera development, so that the percentage of fruits attacked in 2007 at the first scouting was 68.28%. Emamectin benzoate has shown, in two years of testing, a high control of H. armigera if compared with the standards Indoxacarb and Spinosad. No effect of phytotoxicity was noticed on fruits.

Can we stop transgenes from taking a walk on the wild side?

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Dlugosch, Katrina M; Whitton, Jeannette

2008-03-01

Whether the potential costs associated with broad-scale use of genetically modified organisms (GMOs) outweigh possible benefits is highly contentious, including within the scientific community. Even among those generally in favour of commercialization of GM crops, there is nonetheless broad recognition that transgene escape into the wild should be minimized. But is it possible to achieve containment of engineered genetic elements in the context of large scale agricultural production? In a previous study, Warwick et al. (2003) documented transgene escape via gene flow from herbicide resistant (HR) canola (Brassica napus) into neighbouring weedy B. rapa populations (Fig. 1) in two agricultural fields in Quebec, Canada. In a follow-up study in this issue of Molecular Ecology, Warwick et al. (2008) show that the transgene has persisted and spread within the weedy population in the absence of selection for herbicide resistance. Certainly a trait like herbicide resistance is expected to spread when selected through the use of the herbicide, despite potentially negative epistatic effects on fitness. However, Warwick et al.'s findings suggest that direct selection favouring the transgene is not required for its persistence. So is there any hope of preventing transgene escape into the wild?

Laboratory Evaluation of Different Insecticides against Hibiscus Mealybug, Maconellicoccus hirsutus (Hemiptera: Pseudococcidae

Directory of Open Access Journals (Sweden)

Samman Fatima

2016-01-01

Full Text Available Hibiscus mealybug, Maconellicoccus hirsutus (Hemiptera: Pseudococcidae, is the major pest of many vegetables, fruits, crops, and ornamental plants causing losses to the farmers and its control has been an issue of significance in the pest management. This study was aimed at evaluating different concentrations (0.06%, 0.1%, and 0.14% of Telsta, Advantage, Talstar, Imidacloprid, and their mixtures against hibiscus mealybug in the Laboratory of Systematics and Pest Management at University of Gujrat, Pakistan. The toxic effect was evaluated in the laboratory bioassay after 24 and 48 h of the application of insecticides. The highest mortality (95.83% was shown by Talstar and Talstar + Imidacloprid at the concentration of 0.14% after 48 h followed by Advantage + Talstar with 87.50% mortality at 0.14% concentration after 48 h of application. The study also showed that the least effective treatment observed was Advantage + Telsta with no mortality after 24 h and 25% mortality after 48 h at 0.14% concentration. The study revealed that the concentration 0.14% was highly effective in lowering the mealybug population and insecticide mixtures were effective in reducing mealybug density. The study emphasizes the use of such insecticide mixtures to develop better management strategy for mealybug populations attacking ornamental plants. However effects of such insecticide mixtures on other organisms and biological control agents should be checked under field conditions.

Reduced-risk insecticides for control of grape berry moth (Lepidoptera: Tortricidae) and conservation of natural enemies.

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Jenkins, Paul E; Isaacs, Rufus

2007-06-01

A 3-yr field study was conducted at commercial grape (Vitis spp.) farms to evaluate insect management programs for control of the grape berry moth, Paralobesia viteana Clemens (Lepidoptera: Tortricidae) and conservation of natural enemies. At each farm, one vineyard received only reduced-risk insecticides for control of second and third generation P. viteana, whereas the comparison vineyard received conventional insecticides. Both vineyards received a conventional insecticide application for control of first generation P. viteana and other insect pests. Monitoring with pheromone traps showed no differences between programs in the total number of adult male moths trapped in vineyards, and oviposition by P. viteana was similar between the two programs in all 3 yr. During weekly samples of crop infestation, both programs had a similar percentage of clusters infested by P. viteana larvae. Berries infested by P. viteana were collected from vineyard borders during the second and third P. viteana generations and held under controlled conditions. In eight of the nine berry samples, survival of larvae was significantly lower in berries collected from vineyards managed under the reduced-risk insecticide program compared with the conventional program. Parasitism of P. citeana larvae in these samples was not consistently different between the two insecticide programs over 3 yr, and similar captures of natural enemies were found on yellow sticky traps in the two programs throughout the study. Our results indicate that integrated pest management programs incorporating reduced-risk insecticides for control of P. viteana can obtain similar or greater control of P. viteana compared with programs based solely on conventional insecticides, but they may not lead to measurable long-term increases in parasitism of P. viteana.

Insect-resistant biotech crops and their impacts on beneficial arthropods

Science.gov (United States)

Gatehouse, A. M. R.; Ferry, N.; Edwards, M. G.; Bell, H. A.

2011-01-01

With a projected population of 10 billion by 2050, an immediate priority for agriculture is to achieve increased crop yields in a sustainable and cost-effective way. The concept of using a transgenic approach was realized in the mid-1990s with the commercial introduction of genetically modified (GM) crops. By 2010, the global value of the seed alone was US $11.2 billion, with commercial biotech maize, soya bean grain and cotton valued at approximately US $150 billion. In recent years, it has become evident that insect-resistant crops expressing δ-endotoxin genes from Bacillus thuringiensis have made a significant beneficial impact on global agriculture, not least in terms of pest reduction and improved quality. However, because of the potential for pest populations to evolve resistance, and owing to lack of effective control of homopteran pests, alternative strategies are being developed. Some of these are based on Bacillus spp. or other insect pathogens, while others are based on the use of plant- and animal-derived genes. However, if such approaches are to play a useful role in crop protection, it is desirable that they do not have a negative impact on beneficial organisms at higher trophic levels thus affecting the functioning of the agro-ecosystem. This widely held concern over the ecological impacts of GM crops has led to the extensive examination of the potential effects of a range of transgene proteins on non-target and beneficial insects. The findings to date with respect to both commercial and experimental GM crops expressing anti-insect genes are discussed here, with particular emphasis on insect predators and parasitoids. PMID:21444317

Insect-resistant biotech crops and their impacts on beneficial arthropods.

Science.gov (United States)

Gatehouse, A M R; Ferry, N; Edwards, M G; Bell, H A

2011-05-12

With a projected population of 10 billion by 2050, an immediate priority for agriculture is to achieve increased crop yields in a sustainable and cost-effective way. The concept of using a transgenic approach was realized in the mid-1990s with the commercial introduction of genetically modified (GM) crops. By 2010, the global value of the seed alone was US $11.2 billion, with commercial biotech maize, soya bean grain and cotton valued at approximately US $150 billion. In recent years, it has become evident that insect-resistant crops expressing δ-endotoxin genes from Bacillus thuringiensis have made a significant beneficial impact on global agriculture, not least in terms of pest reduction and improved quality. However, because of the potential for pest populations to evolve resistance, and owing to lack of effective control of homopteran pests, alternative strategies are being developed. Some of these are based on Bacillus spp. or other insect pathogens, while others are based on the use of plant- and animal-derived genes. However, if such approaches are to play a useful role in crop protection, it is desirable that they do not have a negative impact on beneficial organisms at higher trophic levels thus affecting the functioning of the agro-ecosystem. This widely held concern over the ecological impacts of GM crops has led to the extensive examination of the potential effects of a range of transgene proteins on non-target and beneficial insects. The findings to date with respect to both commercial and experimental GM crops expressing anti-insect genes are discussed here, with particular emphasis on insect predators and parasitoids.

The phorbol ester fraction from Jatropha curcas seed oil: potential and limits for crop protection against insect pests.

Science.gov (United States)

Ratnadass, Alain; Wink, Michael

2012-11-30

The physic nut shrub, Jatropha curcas (Euphorbiaceae), has been considered as a "miracle tree", particularly as a source of alternate fuel. Various extracts of the plant have been reported to have insecticidal/acaricidal or molluscicidal/anthelminthic activities on vectors of medical or veterinary interest or on agricultural or non-agricultural pests. Among those extracts, the phorbol ester fraction from seed oil has been reported as a promising candidate for use as a plant-derived protectant of a variety of crops, from a range of pre-harvest and post-harvest insect pests. However, such extracts have not been widely used, despite the "boom" in the development of the crop in the tropics during recent years, and societal concerns about overuse of systemic chemical pesticides. There are many potential explanations to such a lack of use of Jatropha insecticidal extracts. On the one hand, the application of extracts potentially harmful to human health on stored food grain, might not be relevant. The problem of decomposition of phorbol esters and other compounds toxic to crop pests in the field needing further evaluation before such extracts can be widely used, may also be a partial explanation. High variability of phorbol ester content and hence of insecticidal activity among physic nut cultivars/ecotypes may be another. Phytotoxicity to crops may be further limitation. Apparent obstacles to a wider application of such extracts are the costs and problems involved with registration and legal approval. On the other hand, more studies should be conducted on molluscicidal activity on slugs and land snails which are major pests of crops, particularly in conservation agriculture systems. Further evaluation of toxicity to natural enemies of insect pests and studies on other beneficial insects such as pollinators are also needed.

The Phorbol Ester Fraction from Jatropha curcas Seed Oil: Potential and Limits for Crop Protection against Insect Pests

Science.gov (United States)

Ratnadass, Alain; Wink, Michael

2012-01-01

The physic nut shrub, Jatropha curcas (Euphorbiaceae), has been considered as a “miracle tree”, particularly as a source of alternate fuel. Various extracts of the plant have been reported to have insecticidal/acaricidal or molluscicidal/anthelminthic activities on vectors of medical or veterinary interest or on agricultural or non-agricultural pests. Among those extracts, the phorbol ester fraction from seed oil has been reported as a promising candidate for use as a plant-derived protectant of a variety of crops, from a range of pre-harvest and post-harvest insect pests. However, such extracts have not been widely used, despite the “boom” in the development of the crop in the tropics during recent years, and societal concerns about overuse of systemic chemical pesticides. There are many potential explanations to such a lack of use of Jatropha insecticidal extracts. On the one hand, the application of extracts potentially harmful to human health on stored food grain, might not be relevant. The problem of decomposition of phorbol esters and other compounds toxic to crop pests in the field needing further evaluation before such extracts can be widely used, may also be a partial explanation. High variability of phorbol ester content and hence of insecticidal activity among physic nut cultivars/ecotypes may be another. Phytotoxicity to crops may be further limitation. Apparent obstacles to a wider application of such extracts are the costs and problems involved with registration and legal approval. On the other hand, more studies should be conducted on molluscicidal activity on slugs and land snails which are major pests of crops, particularly in conservation agriculture systems. Further evaluation of toxicity to natural enemies of insect pests and studies on other beneficial insects such as pollinators are also needed. PMID:23203190

RNAi-derived transgenic resistance to Mungbean yellow mosaic India virus in cowpea.

Science.gov (United States)

Kumar, Sanjeev; Tanti, Bhaben; Patil, Basavaprabhu L; Mukherjee, Sunil Kumar; Sahoo, Lingaraj

2017-01-01

Cowpea is an important grain legume crop of Africa, Latin America, and Southeast Asia. Leaf curl and golden mosaic diseases caused by Mungbean yellow mosaic India virus (MYMIV) have emerged as most devastating viral diseases of cowpea in Southeast Asia. In this study, we employed RNA interference (RNAi) strategy to control cowpea-infecting MYMIV. For this, we generated transgenic cowpea plants harbouring three different intron hairpin RNAi constructs, containing the AC2, AC4 and fusion of AC2 and AC4 (AC2+AC4) of seven cowpea-infecting begomoviruses. The T0 and T1 transgenic cowpea lines of all the three constructs accumulated transgene-specific siRNAs. Transgenic plants were further assayed up to T1 generations, for resistance to MYMIV using agro-infectious clones. Nearly 100% resistance against MYMIV infection was observed in transgenic lines, expressing AC2-hp and AC2+AC4-hp RNA, when compared with untransformed controls and plants transformed with empty vectors, which developed severe viral disease symptoms within 3 weeks. The AC4-hp RNA expressing lines displayed appearance of milder symptoms after 5 weeks of MYMIV-inoculation. Northern blots revealed a positive correlation between the level of transgene-specific siRNAs accumulation and virus resistance. The MYMIV-resistant transgenic lines accumulated nearly zero or very low titres of viral DNA. The transgenic cowpea plants had normal phenotype with no yield penalty in greenhouse conditions. This is the first demonstration of RNAi-derived resistance to MYMIV in cowpea.

Food safety evaluation of crops produced through genetic engineering--how to reduce unintended effects?

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Jelenić, Srećko

2005-06-01

Scientists started applying genetic engineering techniques to improve crops two decades ago; about 70 varieties obtained via genetic engineering have been approved to date. Although genetic engineering offers the most precise and controllable genetic modification of crops in entire history of plant improvement, the site of insertion of a desirable gene cannot be predicted during the application of this technology. As a consequence, unintended effects might occur due to activation or silencing of genes, giving rise to allergic reactions or toxicity. Therefore, extensive chemical, biochemical and nutritional analyses are performed on each new genetically engineered variety. Since the unintended effects may be predictable on the basis of what is known about the insertion place of the transgenic DNA, an important aim of plant biotechnology is to define techniques for the insertion of transgene into the predetermined chromosomal position (gene targeting). Although gene targeting cannot be applied routinely in crop plants, given the recent advances, that goal may be reached in the near future.

Trends in pesticide use on soybean, corn and cotton since the introduction of major genetically modified crops in the United States

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Coupe, Richard H.; Capel, Paul D.

2016-01-01

BACKGROUNDGenetically modified (GM) varieties of soybean, corn and cotton have largely replaced conventional varieties in the United States. The most widely used applications of GM technology have been the development of crops that are resistant to a specific broad-spectrum herbicide (primarily glyphosate) or that produce insecticidal compounds within the plant itself. With the widespread adoption of GM crops, a decline in the use of conventional pesticides was expected.RESULTSThere has been a reduction in the annual herbicide application rate to corn since the advent of GM crops, but the herbicide application rate is mostly unchanged for cotton. Herbicide use on soybean has increased. There has been a substantial reduction in the amount of insecticides used on both corn and cotton since the introduction of GM crops.CONCLUSIONSThe observed changes in pesticide use are likely to be the result of many factors, including the introduction of GM crops, regulatory restrictions on some conventional pesticides, introduction of new pesticide technologies and changes in farming practices. In order to help protect human and environmental health and to help agriculture plan for the future, more detailed and complete documentation on pesticide use is needed on a frequent and ongoing basis.

Simultaneous Expression of PDH45 with EPSPS Gene Improves Salinity and Herbicide Tolerance in Transgenic Tobacco Plants.

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Garg, Bharti; Gill, Sarvajeet S; Biswas, Dipul K; Sahoo, Ranjan K; Kunchge, Nandkumar S; Tuteja, Renu; Tuteja, Narendra

2017-01-01

To cope with the problem of salinity- and weed-induced crop losses, a multi-stress tolerant trait is need of the hour but a combinatorial view of such traits is not yet explored. The overexpression of PDH45 (pea DNA helicase 45) and EPSPS (5-enoylpruvyl shikimate-3-phosphate synthase) genes have been reported to impart salinity and herbicide tolerance. Further, the understanding of mechanism and pathways utilized by PDH45 and EPSPS for salinity and herbicide tolerance will help to improve the crops of economical importance. In the present study, we have performed a comparative analysis of salinity and herbicide tolerance to check the biochemical parameters and antioxidant status of tobacco transgenic plants. Collectively, the results showed that PDH45 overexpressing transgenic lines display efficient tolerance to salinity stress, while PDH45+EPSPS transgenics showed tolerance to both the salinity and herbicide as compared to the control [wild type (WT) and vector control (VC)] plants. The activities of the components of enzymatic antioxidant machinery were observed to be higher in the transgenic plants indicating the presence of an efficient antioxidant defense system which helps to cope with the stress-induced oxidative-damages. Photosynthetic parameters also showed significant increase in PDH45 and PDH45+EPSPS overexpressing transgenic plants in comparison to WT, VC and EPSPS transgenic plants under salinity stress. Furthermore, PDH45 and PDH45+EPSPS synergistically modulate the jasmonic acid and salicylic acid mediated signaling pathways for combating salinity stress. The findings of our study suggest that pyramiding of the PDH45 gene with EPSPS gene renders host plants tolerant to salinity and herbicide by enhancing the antioxidant machinery thus photosynthesis.

Population dynamics of Sesamia inferens on transgenic rice expressing Cry1Ac and CpTI in southern China.

Science.gov (United States)

Han, Lanzhi; Liu, Peilei; Wu, Kongming; Peng, Yufa; Wang, Feng

2008-10-01

Genetically modified insect-resistant rice lines containing the cry1Ac gene from Bacillus thuringiensis (Bt) or the CpTI (cowpea trypsin inhibitor) gene developed for the management of lepidopterous pests are highly resistant to the major target pests, Chilo suppressalis (Walker), Cnaphalocrocis medinalis (Guenée), and Scirpophaga incertulas (Walker), in the main rice-growing areas of China. However, the effects of these transgenic lines on Sesamia inferens (Walker), an important lepidopterous rice pest, are currently unknown. Because different insect species have varying susceptibility to Bt insecticidal proteins that may affect population dynamics, research into the effects of these transgenic rice lines on the population dynamics of S. inferens was conducted in Fuzhou, southern China, in 2005 and 2006. The results of laboratory, field cage, and field plot experiments show that S. inferens has comparatively high susceptibility to the transgenic line during the early growing season, with significant differences observed in larval density and infestation levels between transgenic and control lines. Because of a decrease in Cry1Ac levels in the plant as it ages, the transgenic line provided only a low potential for population suppression late in the growing season. There is a correlation between the changing expression of Cry1Ac and the impact of transgenic rice on the population dynamics of S. inferens during the season. These results indicate that S. inferens may become a major pest in fields of prospective commercially released transgenic rice, and more attention should be paid to developing an effective alternative management strategy.

Genome-editing technologies and their potential application in horticultural crop breeding

Science.gov (United States)

Xiong, Jin-Song; Ding, Jing; Li, Yi

2015-01-01

Plant breeding, one of the oldest agricultural activities, parallels human civilization. Many crops have been domesticated to satisfy human's food and aesthetical needs, including numerous specialty horticultural crops such as fruits, vegetables, ornamental flowers, shrubs, and trees. Crop varieties originated through selection during early human civilization. Other technologies, such as various forms of hybridization, mutation, and transgenics, have also been invented and applied to crop breeding over the past centuries. The progress made in these breeding technologies, especially the modern biotechnology-based breeding technologies, has had a great impact on crop breeding as well as on our lives. Here, we first review the developmental process and applications of these technologies in horticultural crop breeding. Then, we mainly describe the principles of the latest genome-editing technologies and discuss their potential applications in the genetic improvement of horticultural crops. The advantages and challenges of genome-editing technologies in horticultural crop breeding are also discussed. PMID:26504570

Unraveling the effect of structurally different classes of insecticide on germination and early plant growth of soybean [Glycine max (L.) Merr].

Science.gov (United States)

Dhungana, Sanjeev Kumar; Kim, Il-Doo; Kwak, Hwa-Sook; Shin, Dong-Hyun

2016-06-01

Although a considerable number of studies about the effect of different insecticides on plant physiology and metabolism have been carried out, research work about the comparative action of structurally different classes of insecticide on physiological and biochemical properties of soybean seed germination and early growth has not been found. The objective of this study was to investigate the effect of different classes of insecticides on soybean seed germination and early plant growth. Soybean seeds of Bosuk cultivar were soaked for 24h in distilled water or recommended dose (2mLL(-1), 1mLL(-1), 0.5gL(-1), and 0.5gL(-1) water for insecticides Mepthion, Myungtaja, Actara, and Stonate, respectively) of pesticide solutions of four structurally different classes of insecticides - Mepthion (fenitrothion; organophosphate), Myungtaja (etofenprox; pyrethroid), Actara (thiamethoxam; neonicotinoid), and Stonate (lambda-cyhalothrin cum thiamethoxam; pyrethroid cum neonicotinoid) - which are used for controlling stink bugs in soybean crop. Insecticides containing thiamethoxam and lamda-cyhalothrin cum thiamethoxam showed positive effects on seedling biomass and content of polyphenol and flavonoid, however fenitrothion insecticide reduced the seed germination, seed and seedling vigor, and polyphenol and flavonoid contents in soybean. Results of this study reveal that different classes of insecticide have differential influence on physiologic and metabolic actions like germination, early growth, and antioxidant activities of soybean and this implies that yield and nutrient content also might be affected with the application of different types of insecticide. Copyright © 2015 Elsevier B.V. All rights reserved.

Assessment of beneficial role of an insectivorous bird, jungle babbler (Turdoides striatus predation, on Helicoverpa armigera infesting pigeon pea (Cajanus cajan crop

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Bharucha Bhavna

2010-06-01

Full Text Available Jungle babbler (Turdoides striatus, a widely spread sub-tropical insectivorous passerine is considered beneficial to agro-ecosystem, as they devour voraciously on insect matter especially Helicoverpa armigera, the gram pod borer, a notorious pest infesting and causing heavy loses to crops like pigeon pea (Cajanus cajan which is a vital crop of semi-arid tropical and subtropical farming system, providing high quality vegetable protein. Helicoverpa is known to feed on flowers, pods, and seeds and is the most important biotic constraint affecting pigeon pea yields. Jungle babblers have a peculiar foraging style which helps expose the Helicoverpa larvae as well as pupae through various phenological stages of pigeon pea. For comparative assessment of their beneficial role and as a possible bio control agent, in Baroda city (State of Gaujarat, India, was studied, two crops of pigeon pea (insecticide treated and untreated (control were selected. In both treated and control crops, the number of jungle babblers were maximum in pigeon pea fields during october and november in both small pod stage and large pod stage which had heavy infestation of Helicoverpa. Least number of birds was seen during the flowering stage in September. Later in treatment crop three applications of Dunnate and Monocrotophos insecticide spray was done after which the pest population decreased which is reflected in number of birds in the field, while the bird number in control crops grew since insecticide spray was not done and number of larvae increased with the stage of the crop. Along with the main crop pigeon pea, comparative study was also done to see the food preference by these birds in crops like sorghum, maize, cow pea and ploughed and unploughed fields. Maximum number of birds was seen in unploughed field and least in sorghum suggesting that Helicoverpa is preferred food over sorghum grains thus pigeon pea

Transgenic soybeans and soybean protein analysis: an overview.

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Natarajan, Savithiry; Luthria, Devanand; Bae, Hanhong; Lakshman, Dilip; Mitra, Amitava

2013-12-04

To meet the increasing global demand for soybeans for food and feed consumption, new high-yield varieties with improved quality traits are needed. To ensure the safety of the crop, it is important to determine the variation in seed proteins along with unintended changes that may occur in the crop as a result various stress stimuli, breeding, and genetic modification. Understanding the variation of seed proteins in the wild and cultivated soybean cultivars is useful for determining unintended protein expression in new varieties of soybeans. Proteomic technology is useful to analyze protein variation due to various stimuli. This short review discusses transgenic soybeans, different soybean proteins, and the approaches used for protein analysis. The characterization of soybean protein will be useful for researchers, nutrition professionals, and regulatory agencies dealing with soy-derived food products.

Plant Fitness Assessment for Wild Relatives of Insect Resistant Bt-Crops

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D. K. Letourneau

2012-01-01

Full Text Available When field tests of transgenic plants are precluded by practical containment concerns, manipulative experiments can detect potential consequences of crop-wild gene flow. Using topical sprays of bacterial Bacillus thuringiensis larvicide (Bt and larval additions, we measured fitness effects of reduced herbivory on Brassica rapa (wild mustard and Raphanus sativus (wild radish. These species represent different life histories among the potential recipients of Bt transgenes from Bt cole crops in the US and Asia, for which rare spontaneous crosses are expected under high exposure. Protected wild radish and wild mustard seedlings had approximately half the herbivore damage of exposed plants and 55% lower seedling mortality, resulting in 27% greater reproductive success, 14-day longer life-spans, and 118% more seeds, on average. Seed addition experiments in microcosms and in situ indicated that wild radish was more likely to spread than wild mustard in coastal grasslands.

Environmental change challenges decision-making during post-market environmental monitoring of transgenic crops.

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Sanvido, Olivier; Romeis, Jörg; Bigler, Franz

2011-12-01

The ability to decide what kind of environmental changes observed during post-market environmental monitoring of genetically modified (GM) crops represent environmental harm is an essential part of most legal frameworks regulating the commercial release of GM crops into the environment. Among others, such decisions are necessary to initiate remedial measures or to sustain claims of redress linked to environmental liability. Given that consensus on criteria to evaluate 'environmental harm' has not yet been found, there are a number of challenges for risk managers when interpreting GM crop monitoring data for environmental decision-making. In the present paper, we argue that the challenges in decision-making have four main causes. The first three causes relate to scientific data collection and analysis, which have methodological limits. The forth cause concerns scientific data evaluation, which is controversial among the different stakeholders involved in the debate on potential impacts of GM crops on the environment. This results in controversy how the effects of GM crops should be valued and what constitutes environmental harm. This controversy may influence decision-making about triggering corrective actions by regulators. We analyse all four challenges and propose potential strategies for addressing them. We conclude that environmental monitoring has its limits in reducing uncertainties remaining from the environmental risk assessment prior to market approval. We argue that remaining uncertainties related to adverse environmental effects of GM crops would probably be assessed in a more efficient and rigorous way during pre-market risk assessment. Risk managers should acknowledge the limits of environmental monitoring programmes as a tool for decision-making.

Tuning growth cycles of Brassica crops via natural antisense transcripts of BrFLC.

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Li, Xiaorong; Zhang, Shaofeng; Bai, Jinjuan; He, Yuke

2016-03-01

Several oilseed and vegetable crops of Brassica are biennials that require a prolonged winter cold for flowering, a process called vernalization. FLOWERING LOCUS C (FLC) is a central repressor of flowering. Here, we report that the overexpression of natural antisense transcripts (NATs) of Brassica rapa FLC (BrFLC) greatly shortens plant growth cycles. In rapid-, medium- and slow-cycling crop types, there are four copies of the BrFLC genes, which show extensive variation in sequences and expression levels. In Bre, a biennial crop type that requires vernalization, five NATs derived from the BrFLC2 locus are rapidly induced under cold conditions, while all four BrFLC genes are gradually down-regulated. The transgenic Bre lines overexpressing a long NAT of BrFLC2 do not require vernalization, resulting in a gradient of shortened growth cycles. Among them, a subset of lines both flower and set seeds as early as Yellow sarson, an annual crop type in which all four BrFLC genes have non-sense mutations and are nonfunctional in flowering repression. Our results demonstrate that the growth cycles of biennial crops of Brassica can be altered by changing the expression levels of BrFLC2 NATs. Thus, BrFLC2 NATs and their transgenic lines are useful for the genetic manipulation of crop growth cycles. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

Field performance of transgenic citrus trees: assessment of the long-term expression of uidA and nptII transgenes and its impact on relevant agronomic and phenotypic characteristics.

Science.gov (United States)

Pons, Elsa; Peris, Josep E; Peña, Leandro

2012-07-15

The future of genetic transformation as a tool for the improvement of fruit trees depends on the development of proper systems for the assessment of unintended effects in field-grown GM lines. In this study, we used eight transgenic lines of two different citrus types (sweet orange and citrange) transformed with the marker genes β-glucuronidase (uidA) and neomycin phosphotransferase II (nptII) as model systems to study for the first time in citrus the long-term stability of transgene expression and whether transgene-derived pleiotropic effects occur with regard to the morphology, development and fruit quality of orchard-grown GM citrus trees. The stability of the integration and expression of the transgenes was confirmed in 7-year-old, orchard-grown transgenic lines by Southern blot analysis and enzymatic assays (GUS and ELISA NPTII), respectively. Little seasonal variation was detected in the expression levels between plants of the same transgenic line in different organs and over the 3 years of analysis, confirming the absence of rearrangements and/or silencing of the transgenes after transferring the plants to field conditions. Comparisons between the GM citrus lines with their non-GM counterparts across the study years showed that the expression of these transgenes did not cause alterations of the main phenotypic and agronomic plant and fruit characteristics. However, when comparisons were performed between diploid and tetraploid transgenic citrange trees and/or between juvenile and mature transgenic sweet orange trees, significant and consistent differences were detected, indicating that factors other than their transgenic nature induced a much higher phenotypic variability. Our results indicate that transgene expression in GM citrus remains stable during long-term agricultural cultivation, without causing unexpected effects on crop characteristics. This study also shows that the transgenic citrus trees expressing the selectable marker genes that are most

Widespread Use and Frequent Detection of Neonicotinoid Insecticides in Wetlands of Canada's Prairie Pothole Region

OpenAIRE

Main, Anson R.; Headley, John V.; Peru, Kerry M.; Michel, Nicole L.; Cessna, Allan J.; Morrissey, Christy A.

2014-01-01

Neonicotinoids currently dominate the insecticide market as seed treatments on Canada's major Prairie crops (e.g., canola). The potential impact to ecologically significant wetlands in this dominantly agro-environment has largely been overlooked while the distribution of use, incidence and level of contamination remains unreported. We modelled the spatial distribution of neonicotinoid use across the three Prairie Provinces in combination with temporal assessments of water and sediment concent...

Transgenic virus resistance in crop-wild Cucurbita pepo does not prevent vertical transmission of zucchini yellow mosaic virus

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H. E. Simmons; Holly Prendeville; J. P. Dunham; M. J. Ferrari; J. D. Earnest; D. Pilson; G. P. Munkvold; E. C. Holmes; A. G. Stephenson

2015-01-01

Zucchini yellow mosaic virus (ZYMV) is an economically important pathogen of cucurbits that is transmitted both horizontally and vertically. Although ZYMV is seed-transmitted in Cucurbita pepo, the potential for seed transmission in virus-resistant transgenic cultivars is not known. We crossed and backcrossed a transgenic...

Expression of an osmotin-like protein from Solanum nigrum confers drought tolerance in transgenic soybean.

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Weber, Ricardo Luís Mayer; Wiebke-Strohm, Beatriz; Bredemeier, Christian; Margis-Pinheiro, Márcia; de Brito, Giovani Greigh; Rechenmacher, Ciliana; Bertagnolli, Paulo Fernando; de Sá, Maria Eugênia Lisei; Campos, Magnólia de Araújo; de Amorim, Regina Maria Santos; Beneventi, Magda Aparecida; Margis, Rogério; Grossi-de-Sa, Maria Fátima; Bodanese-Zanettini, Maria Helena

2014-12-10

Drought is by far the most important environmental factor contributing to yield losses in crops, including soybeans [Glycine max (L.) Merr.]. To address this problem, a gene that encodes an osmotin-like protein isolated from Solanum nigrum var. americanum (SnOLP) driven by the UBQ3 promoter from Arabidopsis thaliana was transferred into the soybean genome by particle bombardment. Two independently transformed soybean lines expressing SnOLP were produced. Segregation analyses indicated single-locus insertions for both lines. qPCR analysis suggested a single insertion of SnOLP in the genomes of both transgenic lines, but one copy of the hpt gene was inserted in the first line and two in the second line. Transgenic plants exhibited no remarkable phenotypic alterations in the seven analyzed generations. When subjected to water deficit, transgenic plants performed better than the control ones. Leaf physiological measurements revealed that transgenic soybean plants maintained higher leaf water potential at predawn, higher net CO2 assimilation rate, higher stomatal conductance and higher transpiration rate than non-transgenic plants. Grain production and 100-grain weight were affected by water supply. Decrease in grain productivity and 100-grain weight were observed for both transgenic and non-transgenic plants under water deficit; however, it was more pronounced for non-transgenic plants. Moreover, transgenic lines showed significantly higher 100-grain weight than non-transgenic plants under water shortage. This is the first report showing that expression of SnOLP in transgenic soybeans improved physiological responses and yield components of plants when subjected to water deficit, highlighting the potential of this gene for biotechnological applications.

Impact of insecticides on non-target arthropods in watermelon cropImpacto de inseticidas em artrópodes não-alvo associados à cultura da melancia

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Cíntia Ribeiro Souza

2012-10-01

Full Text Available Watermelon Citrullus lunatus (Thunberg, Matsumura & Nakai is an ecosystem having a variety of arthropods, each one playing a specific role. Although some of them are considered pest to crops, some others are responsible for soil aeration, nutrient release and predation of pest species and are, therefore, considered beneficial to crops. The intensive farming practiced for watermelon cultivation in Brazil is based on the use of tiamethoxam and deltamethrin, which may not only kill target but also nontarget organisms such as beneficial arthropods. Research data regarding the influence of insecticides on arthropods in watermelon cropping is scarce. This study aimed to evaluate the effect of the insecticides deltamethrin and thiamethoxam on soil surface and watermelon canopy arthropod community. The study was carried out in the State of Tocantins, Brazil. Although the application of thiamethoxam and deltamethrin was efficient in controlling populations of Aphis gossypii (Glover, as we expected, they negatively affected non-target arthropods such as detritivores insects in the canopy and soil surface. Ecological implications of the impact of such pesticides on beneficial arthropod species are discussed.A cultura da melancia Citrullus lunatus (Thunberg, Matsumura & Nakai abriga uma grande diversidade de artrópodes, cada um desempenhando um papel específico. Apesar de alguns desses artrópodes serem considerados pragas, outros são responsáveis pela aeração do solo, liberação de nutrientes e predação das espécies-praga, sendo, dessa forma, considerados benéficos às culturas. A agricultura intensiva praticada no Brasil para o cultivo da melancia é baseada no uso dos inseticidas como tiamethoxam e deltametrina, que pode não só matar as pragas, mas também organismos não-alvo. Pesquisas relacionadas à influência de inseticidas sobre artrópodes benéficos na cultura da melancia são escassas. Este estudo foi realizado com o objetivo de

Castor phospholipid:diacylglycerol acyltransferase facilitates efficient metabolism of hydroxy fatty acids in transgenic Arabidopsis

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Producing unusual fatty acids (FAs) in crop plants has been a long-standing goal of green chemistry. However, expression of the enzymes that catalyze the primary synthesis of these unusual FAs in transgenic plants typically results in low levels of the desired FA. For example, seed-specific expressi...

Metagenomic-based impact study of transgenic grapevine rootstock on its associated virome and soil microbiome

Science.gov (United States)

For some crops, the only possible approach to gain a specific trait requires genome modification. The development of virus-resistant transgenic plants based on the pathogen-derived resistance strategy has been a success story for over three decades. However, potential risks associated with the techn...

Transgenic oil palm: production and projection.

Science.gov (United States)

Parveez, G K; Masri, M M; Zainal, A; Majid, N A; Yunus, A M; Fadilah, H H; Rasid, O; Cheah, S C

2000-12-01

Oil palm is an important economic crop for Malaysia. Genetic engineering could be applied to produce transgenic oil palms with high value-added fatty acids and novel products to ensure the sustainability of the palm oil industry. Establishment of a reliable transformation and regeneration system is essential for genetic engineering. Biolistic was initially chosen as the method for oil palm transformation as it has been the most successful method for monocotyledons to date. Optimization of physical and biological parameters, including testing of promoters and selective agents, was carried out as a prerequisite for stable transformation. This has resulted in the successful transfer of reporter genes into oil palm and the regeneration of transgenic oil palm, thus making it possible to improve the oil palm through genetic engineering. Besides application of the Biolistics method, studies on transformation mediated by Agrobacterium and utilization of the green fluorescent protein gene as a selectable marker gene have been initiated. Upon the development of a reliable transformation system, a number of useful targets are being projected for oil palm improvement. Among these targets are high-oleate and high-stearate oils, and the production of industrial feedstock such as biodegradable plastics. The efforts in oil palm genetic engineering are thus not targeted as commodity palm oil. Due to the long life cycle of the palm and the time taken to regenerate plants in tissue culture, it is envisaged that commercial planting of transgenic palms will not occur any earlier than the year 2020.

Genomic and environmental selection patterns in two distinct lettuce crop-wild hybrid crosses.

Science.gov (United States)

Hartman, Yorike; Uwimana, Brigitte; Hooftman, Danny A P; Schranz, Michael E; van de Wiel, Clemens C M; Smulders, Marinus J M; Visser, Richard G F; van Tienderen, Peter H

2013-06-01

Genomic selection patterns and hybrid performance influence the chance that crop (trans)genes can spread to wild relatives. We measured fitness(-related) traits in two different field environments employing two different crop-wild crosses of lettuce. We performed quantitative trait loci (QTL) analyses and estimated the fitness distribution of early- and late-generation hybrids. We detected consistent results across field sites and crosses for a fitness QTL at linkage group 7, where a selective advantage was conferred by the wild allele. Two fitness QTL were detected on linkage group 5 and 6, which were unique to one of the crop-wild crosses. Average hybrid fitness was lower than the fitness of the wild parent, but several hybrid lineages outperformed the wild parent, especially in a novel habitat for the wild type. In early-generation hybrids, this may partly be due to heterosis effects, whereas in late-generation hybrids transgressive segregation played a major role. The study of genomic selection patterns can identify crop genomic regions under negative selection across multiple environments and cultivar-wild crosses that might be applicable in transgene mitigation strategies. At the same time, results were cultivar-specific, so that a case-by-case environmental risk assessment is still necessary, decreasing its general applicability.

Novel enabling technologies of gene isolation and plant transformation for improved crop protection

Energy Technology Data Exchange (ETDEWEB)

Torok, Tamas

2013-02-04

Meeting the needs of agricultural producers requires the continued development of improved transgenic crop protection products. The completed project focused on developing novel enabling technologies of gene discovery and plant transformation to facilitate the generation of such products.

Cis-, intra-, subgenesis, genome editing as modern technologies for modifying the crop genomes (review

Directory of Open Access Journals (Sweden)

Н. Е. Волкова

2016-02-01

Full Text Available Purpose. Reviewing the literature on modern technologies of genetic modification of crop genomes. Results. The current state of genetically modified plants creation is analyzed. The information on cis-, intra- and subgenic plants and their comparison with transgenic crops is given. Examples of cis- and intragenesis application for improving characteristics of crops are provided. Such state-of-the-art technology of crop genome modification as genome editing is considered. Conclusions. Technologies for producing cis-, intra-, subgenic plants are rapidly developing and resulting in crops of the 21st century that can solve the problem of food provision for a constantly growing world population with the least contrary to the public interest.

Impact of GM crops on biodiversity.

Science.gov (United States)

Carpenter, Janet E

2011-01-01

The potential impact of GM crops on biodiversity has been a topic of interest both in general as well as specifically in the context of the Convention on Biological Diversity. Agricultural biodiversity has been defined at levels from genes to ecosystems that are involved or impacted by agricultural production (www.cbd.int/agro/whatis.shtml). After fifteen years of commercial cultivation, a substantial body of literature now exists addressing the potential impacts of GM crops on the environment. This review takes a biodiversity lens to this literature, considering the impacts at three levels: the crop, farm and landscape scales. Within that framework, this review covers potential impacts of the introduction of genetically engineered crops on: crop diversity, biodiversity of wild relatives, non-target soil organisms, weeds, land use, non-target above-ground organisms, and area-wide pest suppression. The emphasis of the review is peer-reviewed literature that presents direct measures of impacts on biodiversity. In addition, possible impacts of changes in management practises such as tillage and pesticide use are also discussed to complement the literature on direct measures. The focus of the review is on technologies that have been commercialized somewhere in the world, while results may emanate from non-adopting countries and regions. Overall, the review finds that currently commercialized GM crops have reduced the impacts of agriculture on biodiversity, through enhanced adoption of conservation tillage practices, reduction of insecticide use and use of more environmentally benign herbicides and increasing yields to alleviate pressure to convert additional land into agricultural use.

Locus-dependent selection in crop-wild hybrids of lettuce under field conditions and its implication for GM crop development

OpenAIRE

Hooftman, D.A.P.; Flavell, A.J.; Jansen, J.; Nijs, den, J.C.M.; Syed, N.H.; Sorensen, A.P.; Wengel, ter, P.O.; Wiel, van de, C.C.M.

2011-01-01

Gene escape from crops has gained much attention in the last two decades, as transgenes introgressing into wild populations could affect the latter's ecological characteristics. However, different genes have different likelihoods of introgression. The mixture of selective forces provided by natural conditions creates an adaptive mosaic of alleles from both parental species. We investigated segregation patterns after hybridization between lettuce (Lactuca sativa) and its wild relative, L. serr...

Genomic and environmental selection patterns in two distinct lettuce crop-wild hybrid crosses

OpenAIRE

Hartman, Y.; Uwimana, B.; Hooftman, D.A.P.; Schranz, M.E.; Wiel, van de, C.C.M.; Smulders, M.J.M.; Visser, R.G.F.; Tienderen, van, P.H.

2013-01-01

Genomic selection patterns and hybrid performance influence the chance that crop (trans)genes can spread to wild relatives. We measured fitness(-related) traits in two different field environments employing two different crop?wild crosses of lettuce. We performed quantitative trait loci (QTL) analyses and estimated the fitness distribution of early- and late-generation hybrids. We detected consistent results across field sites and crosses for a fitness QTL at linkage group 7, where a selectiv...

Recent trends of modern bacterial insecticides for pest control practice in integrated crop management system.

Science.gov (United States)

Chattopadhyay, Pritam; Banerjee, Goutam; Mukherjee, Sayantan

2017-05-01

Food security and safety are the major concern in ever expanding human population on the planet earth. Each and every year insect pests cause a serious damage in agricultural field that cost billions of dollars annually to farmers. The loss in term of productivity and high cost of chemical pesticides enhance the production cost. Irrespective use of chemical pesticides (such as Benzene hexachloride, Endosulfan, Aldicarb, and Fenobucarb) in agricultural field raised several types of environmental issues. Furthermore, continuous use of chemical pesticides creates a selective pressure which helps in emerging of resistance pest. These excess chemical pesticide residues also contaminate the environment including the soil and water. Therefore, the biological control of insect pest in the agricultural field gains more importance due to food safety and environment friendly nature. In this regard, bacterial insecticides offer better alternative to chemical pesticides. It not only helps to establish food security through fighting against insect pests but also ensure the food safety. In this review, we have categorized insect pests and the corresponding bacterial insecticides, and critically analyzed the importance and mode of action of bacterial pesticides. We also have summarized the use of biopesticides in integrated pest management system. We have tried to focus the future research area in this field for the upcoming scientists.

Susceptibility of Sogatella furcifera and Laodelphax striatellus (Hemiptera: Delphacidae) to Six Insecticides in China.

Science.gov (United States)

Zhang, Kai; Zhang, Wei; Zhang, Shuai; Wu, Shun-Fan; Ban, Lan-Feng; Su, Jian-Ya; Gao, Cong-Fen

2014-10-01

The whitebacked planthopper, Sogatella furcifera (Horváth), and small brown planthopper, Laodelphax striatellus (Fallén), both are important crop pests throughout China, especially in rice. Application of chemical insecticides is the major control practice. Consequently, insecticide resistance has become an urgent issue. In this study, resistance levels to six conventional insecticides were evaluated for these two species collected from major occurring areas of China. Additionally, imidacloprid- (resistance ratio [RR] = 10.4-fold) and buprofezin (RR = 15.1-fold)-resistant strains of whitebacked planthopper were obtained through laboratory selections for cross-resistance profiling and synergism assessment to understand resistance mechanisms. The results showed that all tested populations of both species exhibited low to high levels of resistance to chlorpyrifos, while remaining susceptible to thiamethoxam. Three of the 14 whitebacked planthopper populations showed low to moderate resistance to imidacloprid, while all small brown planthopper populations reminded susceptible. All small brown planthopper and whitebacked planthopper (except one) populations showed at least moderate resistance (RR = 10.1-271.1) to buprofezin. All small brown planthopper populations remained susceptible to pymetrozine and nitenpyram, and all whitebacked planthopper populations remained susceptible to isoprocarb. The imidacloprid-resistant whitebacked planthopper strain showed no significant cross-resistance to other tested insecticides. However, the buprofezin-resistant strain exhibited a low-level cross-resistance (CR = 3.1) to imidacloprid. Piperonyl butoxide, triphenyl phosphate, and diethylmaleate displayed no synergism effect on the resistant whitebacked planthopper strains. © 2014 Entomological Society of America.

Review of anthraquinone applications for pest management and agricultural crop protection.

Science.gov (United States)

DeLiberto, Shelagh T; Werner, Scott J

2016-10-01

We have reviewed published anthraquinone applications for international pest management and agricultural crop protection from 1943 to 2016. Anthraquinone (AQ) is commonly found in dyes, pigments and many plants and organisms. Avian repellent research with AQ began in the 1940s. In the context of pest management, AQ is currently used as a chemical repellent, perch deterrent, insecticide and feeding deterrent in many wild birds, and in some mammals, insects and fishes. Criteria for evaluation of effective chemical repellents include efficacy, potential for wildlife hazards, phytotoxicity and environmental persistence. As a biopesticide, AQ often meets these criteria of efficacy for the non-lethal management of agricultural depredation caused by wildlife. We summarize published applications of AQ for the protection of newly planted and maturing crops from pest birds. Conventional applications of AQ-based repellents include preplant seed treatments [e.g. corn (Zea mays L.), rice (Oryza sativa L.), sunflower (Helianthus annuus L.), wheat (Triticum spp.), millet (Panicum spp.), sorghum (Sorghum bicolor L.), pelletized feed and forest tree species] and foliar applications for rice, sunflower, lettuce (Lactuca sativa L.), turf, sugar beets (Beta vulgaris L.), soybean (Glycine max L.), sweet corn and nursery, fruit and nut crops. In addition to agricultural repellent applications, AQ has also been used to treat toxicants for the protection of non-target birds. Few studies have demonstrated AQ repellency in mammals, including wild boar (Sus scrofa, L.), thirteen-lined ground squirrels (Ictidomys tridecemlineatus, Mitchill), black-tailed prairie dogs (Cyomys ludovicainus, Ord.), common voles (Microtus arvalis, Pallas), house mice (Mus musculus, L.), Tristram's jirds (Meriones tristrami, Thomas) and black rats (Rattus rattus L.). Natural sources of AQ and its derivatives have also been identified as insecticides and insect repellents. As a natural or synthetic biopesticide, AQ

Crop to wild gene flow: Does more sophisticated research provide better risk assessment?

International Nuclear Information System (INIS)

Jong, Tom J. de; Rong, Jun

2013-01-01

Highlights: ► Genes can sometimes flow from genetically modified crops to wild plants. ► The probability can be predicted from seed production of hybrids and backcrosses. ► Nevertheless predictions about introgression remain uncertain. ► One should be reluctant to ask too much detail in Environmental Risk Assessment. ► Instead possible harm should have a more central place. -- Abstract: Research into introgression, the permanent incorporation of alleles of one species into another, is flourishing and gives new insights into evolution and speciation. The possible transfer of transgenes from crop species to wild relatives is of major concern for regulators. Applicants that want to introduce a genetically modified (GM) crop on the European market need to indicate the likelihood of introgression and its anticipated effects in an Environmental Risk Analysis (ERA). The European Food Safety Association (EFSA) and competent authorities of different countries evaluate the ERA. Predicting which crop alleles will or will not be permanently incorporated into wild populations requires, apart from information on seed production of hybrids, information on how these crop alleles are associated with fitness. Advances in genetics open new avenues to address this question in more detail. We argue, however, that, even with the best techniques, predicting introgression from crop to wild species will always have a considerable margin of uncertainty. One must therefore be prudent to demand more detailed research for the ERA, especially since the possible harm of transgenes in natural populations remains so poorly defined by regulators

Food safety knowledge on the Bt mutant protein Cry8Ka5 employed in the development of coleopteran-resistant transgenic cotton plants

NARCIS (Netherlands)

Felipe Farias, Davi; Peijnenburg, A.A.C.M.; Grossi-de-Sá, Maria F.; Carvalho, A.F.U.

2015-01-01

Insecticidal Cry proteins from Bacillus thuringiensis (Bt) have been exploited in the development of genetically modified (GM) crops for pest control. However, several pests are still difficult to control such as the coleopteran boll weevil Anthonomus grandis. By applying in vitro molecular

Acute contact toxicity test of insecticides (Cipermetrina 25, Lorsban 48E, Thionex 35) on honeybees in the southwestern zone of Uruguay.

Science.gov (United States)

Carrasco-Letelier, Leonidas; Mendoza-Spina, Yamandú; Branchiccela, María Belén

2012-07-01

Glyphosate-resistant soybean cultivation is expanding rapidly in Uruguay, with its land area having increased by 95 times during the past 10 years. Because of the region's Neotropical conditions, insecticide use is required to ensure adequate soybean productivity. However, in areas shared by soybean crops and beekeepers - such as the southwestern zone of Uruguay (SWZU) - the use of insecticides can increase the risks of honeybee death and honey contamination. Uruguayan commercial and legal guidelines set out practices and field doses designed to prevent acute intoxication with insecticides. However, honeybees in the SWZU are predominantly a polyhybrid subspecies different from that used to set international reference values, and hence they may have a different acute toxicity response, thus rendering such precautions ineffective. The aim of this work was to assess the acute toxicity response of polyhybrid honeybees in the SWZU to cypermethrin (commercial formulation: Cipermetrina 25 Agrin®), chlorpyrifos (commercial formulation: Lorsban 48E®), and endosulfan (commercial formulation: Thionex 35®). Acute toxicity bioassays were conducted to determine the median lethal dose (LD(50)) of each insecticide for the honeybees. The results indicate that, compared with EU reference values, SWZU honeybees have a higher toxicological sensitivity to chlorpyrifos and endosulfan, and a lower toxicological sensitivity to cypermethrin, based on the commercial formulations tested. However, when these results were adjusted according to their field dose equivalents, only chlorpyrifos emerged as a potential problem for beekeeping, as the maximum recommended field dose of Lorsban 48E® for soybean crops in Uruguay is 23 times the corresponding LD(50) for honeybees in the SWZU. Copyright © 2012 Elsevier Ltd. All rights reserved.

Bacillus thuringiensis monogenic strains: screening and interactions with insecticides used against rice pests

Science.gov (United States)

Pinto, Laura M.N.; Dörr, Natália C.; Ribeiro, Ana Paula A.; de Salles, Silvia M.; de Oliveira, Jaime V.; Menezes, Valmir G.; Fiuza, Lidia M.

2012-01-01

The screening of Bacillus thuringiensis (Bt) Cry proteins with high potential to control insect pests has been the goal of numerous research groups. In this study, we evaluated six monogenic Bt strains (Bt dendrolimus HD-37, Bt kurstaki HD-1, Bt kurstaki HD-73, Bt thuringiensis 4412, Bt kurstaki NRD-12 and Bt entomocidus 60.5, which codify the cry1Aa, cry1Ab, cry1Ac, cry1Ba, cry1C, cry2A genes respectively) as potential insecticides for the most important insect pests of irrigated rice: Spodoptera frugiperda, Diatraea saccharalis, Oryzophagus oryzae, Oebalus poecilus and Tibraca limbativentris. We also analyzed their compatibility with chemical insecticides (thiamethoxam, labdacyhalothrin, malathion and fipronil), which are extensively used in rice crops. The bioassay results showed that Bt thuringiensis 4412 and Bt entomocidus 60.5 were the most toxic for the lepidopterans, with a 93% and 82% mortality rate for S. frugiperda and D. saccharalis, respectively. For O. oryzae, the Bt kurstaki NRD-12 (64%) and Bt dendrolimus HD-37 (62%) strains were the most toxic. The Bt dendrolimus HD-37 strain also caused high mortality (82%) to O. poecilus, however the strains assessed to T. limbativentris caused a maximum rate of 5%. The assays for the Bt strains interaction with insecticides revealed the compatibility of the six strains with the four insecticides tested. The results from this study showed the high potential of cry1Aa and cry1Ba genes for genetic engineering of rice plants or the strains to biopesticide formulations. PMID:24031872

Exploration of Novel Botanical Insecticide Leads: Synthesis and Insecticidal Activity of β-Dihydroagarofuran Derivatives.

Science.gov (United States)

Zhao, Ximei; Xi, Xin; Hu, Zhan; Wu, Wenjun; Zhang, Jiwen

2016-02-24

The discovery of novel leads and new mechanisms of action is of vital significance to the development of pesticides. To explore lead compounds for botanical insecticides, 77 β-dihydroagarofuran derivatives were designed and synthesized. Their structures were mainly confirmed by (1)H NMR, (13)C NMR, DEPT-135°, IR, MS, and HRMS. Their insecticidal activity was evaluated against the third-instar larvae of Mythimna separata Walker, and the results indicated that, of these derivatives, eight exhibited more promising insecticidal activity than the positive control, celangulin-V. Particularly, compounds 5.7, 6.6, and 6.7 showed LD50 values of 37.9, 85.1, and 21.1 μg/g, respectively, which were much lower than that of celangulin-V (327.6 μg/g). These results illustrated that β-dihydroagarofuran ketal derivatives can be promising lead compounds for developing novel mechanism-based and highly effective botanical insecticides. Moreover, some newly discovered structure-activity relationships are discussed, which may provide some important guidance for insecticide development.

Transgenic approaches for development of disease resistance in banana

International Nuclear Information System (INIS)

Shekhawat, Upendra K.S.; Ghag, Siddhesh B.; Ganapathi, Thumballi R.

2014-01-01

Banana (Musa spp.) is an important food and cash crop worldwide. Diseases and pests pose the most serious constraint to banana cultivation. Among the diseases, Fusarium wilt and Banana Bunchy Top Virus (BBTV) are the most important economically. We have explored different transgenic approaches for development of efficient resistance in banana against these two diseases. For countering Fusarium wilt, we have over expressed Petunia floral defensins using a strong constitutive promoter in transgenic banana plants. We have also tested a host induced gene silencing strategy targeting two vital fungal genes to obtain Fusarium resistant banana plants. For development of BBTV resistant banana plants also, we have used a host-induced gene silencing approach utilizing the full and partial coding sequence of the viral replication initiation protein. Successful bioassays performed in controlled greenhouse conditions have shown the efficacy of using these strategies to develop disease resistant banana plants. (author)

Mesoionic Pyrido[1,2-a]pyrimidinone Insecticides: From Discovery to Triflumezopyrim and Dicloromezotiaz.

Science.gov (United States)

Zhang, Wenming

2017-09-19

One of the greatest global challenges is to feed the ever-increasing world population. The agrochemical tools growers currently utilize are also under continuous pressure, due to a number of factors that contribute to the loss of existing products. Mesoionic pyrido[1,2-a]pyrimidinones are an unusual yet very intriguing class of compounds. Known for several decades, this class of compounds had not been systemically studied until we started our insecticide discovery program. This Account provides an overview of the efforts on mesoionic pyrido[1,2-a]pyridinone insecticide discovery, beginning from the initial high throughput screen (HTS) discovery to ultimate identification of triflumezopyrim (4, DuPont Pyraxalt) and dicloromezotiaz (5) for commercialization as novel insecticides. Mesoionic pyrido[1,2-a]pyrimidinones with a n-propyl group at the 1-position, such as compound 1, were initially isolated as undesired byproducts from reactions for a fungicide discovery program at DuPont Crop Protection. Such compounds showed interesting insecticidal activity in a follow-up screen and against an expanded insect species list. The area became an insecticide hit for exploration and then a lead area for optimization. At the lead optimization stage, variations at three regions of compound 1, i.e., side-chain (n-propyl group), substituents on the 3-phenyl group, and substitutions on the pyrido- moiety, were explored with many analogues prepared and evaluated. Breakthrough discoveries included replacing the n-propyl group with a 2,2,2-trifluoroethyl group to generate compound 2, and then with a 2-chlorothiazol-5-ylmethyl group to form compound 3. 3 possesses potent insecticidal activity not only against a group of hopper species, including corn planthopper (Peregrinus maidis (Ashmead), CPH) and potato leafhopper (Empoasca fabae (Harris), PLH), as well as two key rice hopper species, namely, brown planthopper (Nilaparvata lugens (Stål), BPH) and rice green leafhopper (Nephotettix

Reduced Insecticide Susceptibility in Aedes vexans (Diptera: Culicidae) Where Agricultural Pest Management Overlaps With Mosquito Abatement.

Science.gov (United States)

Dunbar, Mike W; Bachmann, Amanda; Varenhorst, Adam J

2018-05-04

Mosquito abatement programs in Midwestern communities frequently exist within landscapes dominated by agriculture. Although separately managed, both agricultural pests and mosquitoes are targeted by similar classes of insecticides. As a result, there is the potential for unintended insecticide exposure to mosquito populations from agricultural pest management. To determine the impact that agricultural management practices have on mosquito insecticide susceptibility we compared the mortality of Aedes vexans (Meigen; Diptera: Culicidae) between populations sampled from locations with and without mosquito abatement in South Dakota, a region dominated by agricultural production. Collection locations were either within towns with mosquito abatement programs (n = 2; Brookings and Sioux Falls, SD) or located > 16 km from towns with mosquito abatement programs (n = 2; areas near Harrold and Willow Lake, SD). WHO bioassays were used to test susceptibly of adults to differing insecticide classes relative to their respective controls; 1) an organochlorine (dieldrin 4%), 2) an organophosphate (malathion 5%), and 3) a pyrethroid (lambda-cyhalothrin 0.05%). Corrected mortality did not significantly differ between locations with or without abatement; however, when locations were analized by proportion of developed land within the surrounding landscape pyrethroid mortality was significantly lower where crop production dominated the surrounding landscape and mosquito abatement was present. These data suggest that agricultural pest management may incidentally contribute to reduced mosquito susceptibility where overlap between agricultural pest management and mosquito abatement exists. Decoupling insecticide classes used by both agricultural and public health pest management programs may be necessary to ensure continued efficacy of pest management tools.

Metabolomics of Genetically Modified Crops

Science.gov (United States)

Simó, Carolina; Ibáñez, Clara; Valdés, Alberto; Cifuentes, Alejandro; García-Cañas, Virginia

2014-01-01

Metabolomic-based approaches are increasingly applied to analyse genetically modified organisms (GMOs) making it possible to obtain broader and deeper information on the composition of GMOs compared to that obtained from traditional analytical approaches. The combination in metabolomics of advanced analytical methods and bioinformatics tools provides wide chemical compositional data that contributes to corroborate (or not) the substantial equivalence and occurrence of unintended changes resulting from genetic transformation. This review provides insight into recent progress in metabolomics studies on transgenic crops focusing mainly in papers published in the last decade. PMID:25334064

Metabolomics of Genetically Modified Crops

Directory of Open Access Journals (Sweden)

Carolina Simó

2014-10-01

Full Text Available Metabolomic-based approaches are increasingly applied to analyse genetically modified organisms (GMOs making it possible to obtain broader and deeper information on the composition of GMOs compared to that obtained from traditional analytical approaches. The combination in metabolomics of advanced analytical methods and bioinformatics tools provides wide chemical compositional data that contributes to corroborate (or not the substantial equivalence and occurrence of unintended changes resulting from genetic transformation. This review provides insight into recent progress in metabolomics studies on transgenic crops focusing mainly in papers published in the last decade.

Metamorphosis of cisgenic insect resistance research in the transgenic crop era

Science.gov (United States)

The biotechnological revolution has forever changed agricultural research and crop production worldwide. Commercial agriculture now includes plants that produce enhanced yield and quality, survival in hostile environmental conditions, manufacture and express defensive toxins, and yield grains with ...

Effects of Bt-transgenic rice cultivation on planktonic communities in paddy fields and adjacent ditches

Energy Technology Data Exchange (ETDEWEB)

Liu, Yongbo, E-mail: liuyb@craes.org.cn [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Liu, Fang [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Wang, Chao [Pearl River Fisheries Research Institute, Chinese Academy of Fishery Science, Guangzhou 510380 (China); Quan, Zhanjun [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Li, Junsheng, E-mail: lijsh@creas.org.cn [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China)

2016-09-15

The non-target effects of transgenic plants are issues of concern; however, their impacts in cultivated agricultural fields and adjacent natural aquatic ecosystems are poorly understood. We conducted field experiments during two growing seasons to determine the effects of cultivating Bacillus thuringiensis (Bt)-transgenic rice on the phytoplankton and zooplankton communities in a paddy field and an adjacent ditch. Bt toxin was detected in soil but not in water. Water quality was not significantly different between non-Bt and Bt rice fields, but varied among up-, mid- and downstream locations in the ditch. Cultivation of Bt-transgenic rice had no effects on zooplankton communities. Phytoplankton abundance and biodiversity were not significantly different between transgenic and non-transgenic rice fields in 2013; however, phytoplankton were more abundant in the transgenic rice field than in the non-transgenic rice field in 2014. Water quality and rice type explained 65.9% and 12.8% of this difference in 2014, respectively. Phytoplankton and zooplankton were more abundant in mid- and downstream, than upstream, locations in the ditch, an effect that we attribute to water quality differences. Thus, the release of Bt toxins into field water during the cultivation of transgenic crops had no direct negative effects on plankton community composition, but indirect effects that alter environmental conditions should be taken into account during the processes of management planning and policymaking. - Highlights: • We detect fusion Cry1Ab/1Ac proteins from Bt rice entering into aquatic ecosystems. • Bt-transgenic rice cultivation have no significant effect on zooplankton community. • Bt-transgenic rice cultivation have indirect effect on phytoplankton community. • Water quality explains the difference of plankton communities in adjacent ditches.

Effects of Bt-transgenic rice cultivation on planktonic communities in paddy fields and adjacent ditches

International Nuclear Information System (INIS)

Liu, Yongbo; Liu, Fang; Wang, Chao; Quan, Zhanjun; Li, Junsheng

2016-01-01

The non-target effects of transgenic plants are issues of concern; however, their impacts in cultivated agricultural fields and adjacent natural aquatic ecosystems are poorly understood. We conducted field experiments during two growing seasons to determine the effects of cultivating Bacillus thuringiensis (Bt)-transgenic rice on the phytoplankton and zooplankton communities in a paddy field and an adjacent ditch. Bt toxin was detected in soil but not in water. Water quality was not significantly different between non-Bt and Bt rice fields, but varied among up-, mid- and downstream locations in the ditch. Cultivation of Bt-transgenic rice had no effects on zooplankton communities. Phytoplankton abundance and biodiversity were not significantly different between transgenic and non-transgenic rice fields in 2013; however, phytoplankton were more abundant in the transgenic rice field than in the non-transgenic rice field in 2014. Water quality and rice type explained 65.9% and 12.8% of this difference in 2014, respectively. Phytoplankton and zooplankton were more abundant in mid- and downstream, than upstream, locations in the ditch, an effect that we attribute to water quality differences. Thus, the release of Bt toxins into field water during the cultivation of transgenic crops had no direct negative effects on plankton community composition, but indirect effects that alter environmental conditions should be taken into account during the processes of management planning and policymaking. - Highlights: • We detect fusion Cry1Ab/1Ac proteins from Bt rice entering into aquatic ecosystems. • Bt-transgenic rice cultivation have no significant effect on zooplankton community. • Bt-transgenic rice cultivation have indirect effect on phytoplankton community. • Water quality explains the difference of plankton communities in adjacent ditches.

Genomic and environmental selection patterns in two distinct lettuce crop-wild hybrid crosses

NARCIS (Netherlands)

Hartman, Y.; Uwimana, B.; Hooftman, D.A.P.; Schranz, M.E.; Wiel, van de C.C.M.; Smulders, M.J.M.; Visser, R.G.F.; Tienderen, van P.H.

2013-01-01

Genomic selection patterns and hybrid performance influence the chance that crop (trans)genes can spread to wild relatives. We measured fitness(-related) traits in two different field environments employing two different crop–wild crosses of lettuce. We performed quantitative trait loci (QTL)

A dietary risk assessment of the pyrethroid insecticide resmethrin associated with its use for West Nile Virus mosquito vector control in California

Directory of Open Access Journals (Sweden)

Wesley C. Carr

2006-01-01

Full Text Available An outbreak of human illnesses associated with West Nile Virus (WNV occurred in New York City in 1999. Since then, it has gradually spread westwards, reaching northern California for the first time in 2005. WNV is transmitted by several mosquito species and birds serve as the main reservoir. Several control measures have been used, targeting both the aquatic larvae and the adult mosquitoes. In the latter case, roosting birds in trees are sprayed with pyrethroid insecticides because these are highly toxic to mosquitoes, but have low avian toxicity. A request was made to use a resmethrin-containing insecticide during the month of October 2005 in California. Because resmethrin was not registered for use on growing crops, concerns were raised about potential crop contamination. Therefore, an expedited dietary risk assessment was conducted on resmethrin. Developmental toxicity in the rat (NOELs of 25 or 40 mg/kg/day was used as the acute endpoint and dietary exposure was assessed using the DEEM-FCIDTM computer program. Only crops growing above ground during October were considered. Margins of Safety (MOS were found to be above 100, the level generally considered to be sufficient to protect public health when using an animal NOEL.

Detection of transgenes in local maize varieties of small-scale farmers in eastern cape, South Africa.

Directory of Open Access Journals (Sweden)

Marianne Iversen

Full Text Available Small-scale subsistence farmers in South Africa have been introduced to genetically modified (GM crops for more than a decade. Little is known about i the extent of transgene introgression into locally recycled seed, ii what short and long-term ecological and socioeconomic impacts such mixing of seeds might have, iii how the farmers perceive GM crops, and iv to what degree approval conditions are followed and controlled. This study conducted in the Eastern Cape, South Africa, aims primarily at addressing the first of these issues. We analysed for transgenes in 796 individual maize plants (leaves and 20 seed batches collected in a village where GM insect resistant maize was previously promoted and grown as part of an governmental agricultural development program over a seven year period (2001-2008. Additionally, we surveyed the varieties of maize grown and the farmers' practices of recycling and sharing of seed in the same community (26 farmers were interviewed. Recycling and sharing of seeds were common in the community and may contribute to spread and persistence of transgenes in maize on a local or regional level. By analysing DNA we found that the commonly used transgene promoter p35s occurred in one of the 796 leaf samples (0.0013% and in five of the 20 seed samples (25%. Three of the 20 seed samples (15% included herbicide tolerant maize (NK603 intentionally grown by the farmers from seed bought from local seed retailers or acquired through a currently running agricultural development program. The two remaining positive seed samples (10% included genes for insect resistance (from MON810. In both cases the farmers were unaware of the transgenes present. In conclusion, we demonstrate that transgenes are mixed into seed storages of small-scale farming communities where recycling and sharing of seeds are common, i.e. spread beyond the control of the formal seed system.

The use of whole food animal studies in the safety assessment of genetically modified crops: Limitations and recommendations

Science.gov (United States)

Bartholomaeus, Andrew; Parrott, Wayne; Bondy, Genevieve

2013-01-01

There is disagreement internationally across major regulatory jurisdictions on the relevance and utility of whole food (WF) toxicity studies on GM crops, with no harmonization of data or regulatory requirements. The scientific value, and therefore animal ethics, of WF studies on GM crops is a matter addressable from the wealth of data available on commercialized GM crops and WF studies on irradiated foods. We reviewed available GM crop WF studies and considered the extent to which they add to the information from agronomic and compositional analyses. No WF toxicity study was identified that convincingly demonstrated toxicological concern or that called into question the adequacy, sufficiency, and reliability of safety assessments based on crop molecular characterization, transgene source, agronomic characteristics, and/or compositional analysis of the GM crop and its near-isogenic line. Predictions of safety based on crop genetics and compositional analyses have provided complete concordance with the results of well-conducted animal testing. However, this concordance is primarily due to the improbability of de novo generation of toxic substances in crop plants using genetic engineering practices and due to the weakness of WF toxicity studies in general. Thus, based on the comparative robustness and reliability of compositional and agronomic considerations and on the absence of any scientific basis for a significant potential for de novo generation of toxicologically significant compositional alterations as a sole result of transgene insertion, the conclusion of this review is that WF animal toxicity studies are unnecessary and scientifically unjustifiable. PMID:24164514

The use of whole food animal studies in the safety assessment of genetically modified crops: limitations and recommendations.

Science.gov (United States)

Bartholomaeus, Andrew; Parrott, Wayne; Bondy, Genevieve; Walker, Kate

2013-11-01

There is disagreement internationally across major regulatory jurisdictions on the relevance and utility of whole food (WF) toxicity studies on GM crops, with no harmonization of data or regulatory requirements. The scientific value, and therefore animal ethics, of WF studies on GM crops is a matter addressable from the wealth of data available on commercialized GM crops and WF studies on irradiated foods. We reviewed available GM crop WF studies and considered the extent to which they add to the information from agronomic and compositional analyses. No WF toxicity study was identified that convincingly demonstrated toxicological concern or that called into question the adequacy, sufficiency, and reliability of safety assessments based on crop molecular characterization, transgene source, agronomic characteristics, and/or compositional analysis of the GM crop and its near-isogenic line. Predictions of safety based on crop genetics and compositional analyses have provided complete concordance with the results of well-conducted animal testing. However, this concordance is primarily due to the improbability of de novo generation of toxic substances in crop plants using genetic engineering practices and due to the weakness of WF toxicity studies in general. Thus, based on the comparative robustness and reliability of compositional and agronomic considerations and on the absence of any scientific basis for a significant potential for de novo generation of toxicologically significant compositional alterations as a sole result of transgene insertion, the conclusion of this review is that WF animal toxicity studies are unnecessary and scientifically unjustifiable.

TALE nucleases and next generation GM crops.

KAUST Repository

Mahfouz, Magdy M.

2011-04-01

Site-specific and adaptable DNA binding domains are essential modules to develop genome engineering technologies for crop improvement. Transcription activator-like effectors (TALEs) proteins are used to provide a highly specific and adaptable DNA binding modules. TALE chimeric nucleases (TALENs) were used to generate site-specific double strand breaks (DSBs) in vitro and in yeast, Caenorhabditis elegans, mammalian and plant cells. The genomic DSBs can be generated at predefined and user-selected loci and repaired by either the non-homologous end joining (NHEJ) or homology dependent repair (HDR). Thus, TALENs can be used to achieve site-specific gene addition, stacking, deletion or inactivation. TALE-based genome engineering tools should be powerful to develop new agricultural biotechnology approaches for crop improvement. Here, we discuss the recent research and the potential applications of TALENs to accelerate the generation of genomic variants through targeted mutagenesis and to produce a non-transgenic GM crops with the desired phenotype.

Systemic insecticides (neonicotinoids and fipronil): trends, uses, mode of action and metabolites : Environmental Science and Pollution Research

OpenAIRE

Simon-Delso, N.; Amaral-Rogers, V.; Belzunces, L.P.; Bonmatin, J.M.; Chagnon, M.; Downs, C.; Furlan, L.; Gibbons, D.W.; Giorio, C.; Girolami, V.; Goulson, D.; Kreutzweiser, D.P.; Krupke, C.H.; Liess, M.; Long, E.

2015-01-01

Since their discovery in the late 1980s, neonicotinoid pesticides have become the most widely used class of insecticides worldwide, with large-scale applications ranging from plant protection (crops, vegetables, fruits), veterinary products, and biocides to invertebrate pest control in fish farming. In this review, we address the phenyl-pyrazole fipronil together with neonicotinoids because of similarities in their toxicity, physicochemical profiles, and presence in the environment. Neonicoti...

Amplification of a cytochrome P450 gene is associated with resistance to neonicotinoid insecticides in the aphid Myzus persicae.

Science.gov (United States)

Puinean, Alin M; Foster, Stephen P; Oliphant, Linda; Denholm, Ian; Field, Linda M; Millar, Neil S; Williamson, Martin S; Bass, Chris

2010-06-24

The aphid Myzus persicae is a globally significant crop pest that has evolved high levels of resistance to almost all classes of insecticide. To date, the neonicotinoids, an economically important class of insecticides that target nicotinic acetylcholine receptors (nAChRs), have remained an effective control measure; however, recent reports of resistance in M. persicae represent a threat to the long-term efficacy of this chemical class. In this study, the mechanisms underlying resistance to the neonicotinoid insecticides were investigated using biological, biochemical, and genomic approaches. Bioassays on a resistant M. persicae clone (5191A) suggested that P450-mediated detoxification plays a primary role in resistance, although additional mechanism(s) may also contribute. Microarray analysis, using an array populated with probes corresponding to all known detoxification genes in M. persicae, revealed constitutive over-expression (22-fold) of a single P450 gene (CYP6CY3); and quantitative PCR showed that the over-expression is due, at least in part, to gene amplification. This is the first report of a P450 gene amplification event associated with insecticide resistance in an agriculturally important insect pest. The microarray analysis also showed over-expression of several gene sequences that encode cuticular proteins (2-16-fold), and artificial feeding assays and in vivo penetration assays using radiolabeled insecticide provided direct evidence of a role for reduced cuticular penetration in neonicotinoid resistance. Conversely, receptor radioligand binding studies and nucleotide sequencing of nAChR subunit genes suggest that target-site changes are unlikely to contribute to resistance to neonicotinoid insecticides in M. persicae.

Community and species-specific responses of wild bees to insect pest control programs applied to a pollinator-dependent crop.

Science.gov (United States)

Tuell, Julianna K; Isaacs, Rufus

2010-06-01

Wild bee conservation is regarded as essential for sustainable production of pollinator-dependent crops, yet little is known about the effects on wild bee communities of typical insect pest management programs used postbloom. We developed an insecticide program risk (IPR) index to quantify the relative risk to wild bees of insecticide programs applied to blueberry fields. This was used to determine the relationship between IPR and the abundance, diversity, and richness of wild bee communities sampled during three successive flowering seasons. In 2 of 3 yr, bee abundance and species richness declined with increasing IPR. Bee diversity declined with IPR in one of 3 yr. These results indicate that wild bee communities are negatively affected by increasingly intensive chemical pest management activities in crop fields and that interyear variability in bee populations has the potential to mask such effects in short-term studies. When several wild bee species were analyzed separately, two of three solitary and one of three social blueberry-foraging species declined with increasing IPR values, suggesting that different life histories and nesting habits may help some bee populations escape the negative effects of insecticides applied after bloom. Pollinator conservation programs aimed strictly at reducing insecticide use may have varying success, depending on the biology of the target bee species. The IPR index provides a standard method to compare pest management programs for their potential effect on wild bee communities, with broad application for use in other agricultural systems.

Stress-inducible expression of At DREB1A in transgenic peanut (Arachis hypogaea L.) increases transpiration efficiency under water-limiting conditions.

Science.gov (United States)

Bhatnagar-Mathur, Pooja; Devi, M Jyostna; Reddy, D Srinivas; Lavanya, M; Vadez, Vincent; Serraj, R; Yamaguchi-Shinozaki, K; Sharma, Kiran K

2007-12-01

Water deficit is the major abiotic constraint affecting crop productivity in peanut (Arachis hypogaea L.). Water use efficiency under drought conditions is thought to be one of the most promising traits to improve and stabilize crop yields under intermittent water deficit. A transcription factor DREB1A from Arabidopsis thaliana, driven by the stress inducible promoter from the rd29A gene, was introduced in a drought-sensitive peanut cultivar JL 24 through Agrobacterium tumefaciens-mediated gene transfer. The stress inducible expression of DREB1A in these transgenic plants did not result in growth retardation or visible phenotypic alterations. T3 progeny of fourteen transgenic events were exposed to progressive soil drying in pot culture. The soil moisture threshold where their transpiration rate begins to decline relative to control well-watered (WW) plants and the number of days needed to deplete the soil water was used to rank the genotypes using the average linkage cluster analysis. Five diverse events were selected from the different clusters and further tested. All the selected transgenic events were able to maintain a transpiration rate equivalent to the WW control in soils dry enough to reduce transpiration rate in wild type JL 24. All transgenic events except one achieved higher transpiration efficiency (TE) under WW conditions and this appeared to be explained by a lower stomatal conductance. Under water limiting conditions, one of the selected transgenic events showed 40% higher TE than the untransformed control.

Evaluation of Environmental Risks in the Use of Insecticide in Hashtgerd Area using EIQ

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seyae jala yadollahi Nooshabadi

2018-02-01

into account. Information on types of pesticides through questionnaires and interviews with farmers of all crops and gardens in the area (120 questionnaires in four cities in the study area were collected. Information on pesticides and their effects from data bases IUPAC and the Pesticide Manual, 1997and Crop Protection, 2003 were collected. Results and Discussion Because EIQ index for imidacloprid, diazinon, malathion and phosalone pesticides has been most affected by the ecological effects, It can be concluded that in the land area that these insecticides were used, biotic intensity are at highest risk. In a study that examined environmental hazards of cotton production in Turkey, the role of ecological effects of pesticides on EIQ was more than consumer parts and farm workers. In examining of the pesticides registered in the United States, toxicity of farm workers, consumers and ecological were 37, 8 and 84/4 respectively and the final average EIQ for insecticides registered was 43/1. According to this another factor considered is the farm environmental impact of pesticides. Malathion insecticide in Hashtgerd region with farm environmental impact 42/18 as the most dangerous environmental toxins known and then insecticide diazinon that had the highest consumption in frequency of use, with farm environmental impact 41/76 was next in rank. Although Imidaclopride compared to other pesticides had a higher EIQ index so the potential toxicity was more but because of active ingredient and low dosage in terms of farm environmental impact was in third place. Therefore, with the expansion of the ecosystem-based approach to manage pests and method of integrated pest management, it can be greatly reduced environmental hazards arising from the use of insecticides. Among the major insecticides used in the Hashtgerd region potential toxicity of imidaclopride and farm environmental impact of malathion was more. The highest risk in all three components of farm workers, consumers and

Toxicity and Residual Activity of Insecticides Against Tamarixia triozae (Hymenoptera: Eulophidae), a Parasitoid of Bactericera cockerelli (Hemiptera: Triozidae).

Science.gov (United States)

Luna-Cruz, Alfonso; Rodríguez-Leyva, Esteban; Lomeli-Flores, J Refugio; Ortega-Arenas, Laura D; Bautista-Martínez, Néstor; Pineda, Samuel

2015-10-01

Bactericera cockerelli (Sulc) (Hemiptera: Triozidae) is one of the most economically important pests of potato, tomato, and peppers in Central America, Mexico, the United States, and New Zealand. Its control is based on the use of insecticides; however, recently, the potential of the eulophid parasitoid Tamarixia triozae (Burks) (Hymenoptera: Eulophidae) for population regulation has been studied. Because T. triozae is likely to be exposed to insecticides on crops, the objective of this study was to explore the compatibility of eight insecticides with this parasitoid. The toxicity and residual activity (persistence) of spirotetramat, spiromesifen, beta-cyfluthrin, pymetrozine, azadirachtin, imidacloprid, abamectin, and spinosad against T. triozae adults were assessed using a method based on the residual contact activity of each insecticide on tomato leaf discs collected from treated plants growing under greenhouse conditions. All eight insecticides were toxic to T. triozae. Following the classification of the International Organization of Biological Control, the most toxic were abamectin and spinosad, which could be placed in toxicity categories 3 and 4, respectively. The least toxic were azadirachtin, pymetrozine, spirotetramat, spiromesifen, imidacloprid, and beta-cyfluthrin, which could be placed in toxicity category 2. In terms of persistence, by day 5, 6, 9, 11, 13, 24, and 41 after application, spirotetramat, azadirachtin, spiromesifen, pymetrozine, imidacloprid, beta-cyfluthrin, abamectin, and spinosad could be considered harmless, that is, placed in toxicity category 1 (<25% mortality of adults). The toxicity and residual activity of some of these insecticides allow them to be considered within integrated pest management programs that include T. triozae. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Acute toxicity of chlorantraniliprole to non-target crayfish (Procambarus clarkii) associated with rice-crayfish cropping systems.

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Barbee, Gary C; McClain, W Ray; Lanka, Srinivas K; Stout, Michael J

2010-09-01

Chlorantraniliprole, a novel anthranilic diamide insecticide, was recently introduced into the United States where rice-crayfish crop rotations are practiced to control rice water weevil (Lissorhoptrus oryzophilus Kuschel) infestations. Chlorantraniliprole has high margins of mammalian safety and excellent insecticidal efficacy, but its toxicity to non-target crayfish is uncertain. In this study, the acute toxicity of chlorantraniliprole to the red swamp crayfish Procambarus clarkii Girard was determined using aquatic and feeding assays. The aquatic 96 h median lethal toxicity (LC(50)) data indicate that technical-grade chlorantraniliprole is highly toxic (US EPA category) to crayfish with an LC(50) of 951 microg L(-1) (95% CL = 741-1118 microg L(-1)). A no observed effect concentration (NOEC) of 480 microg L(-1) was recorded. Neither the 36 day chronic feeding study, where crayfish fed on chlorantraniliprole-treated rice seed in aquaria, nor the 144 h acute feeding test, where crayfish fed on rice seeds treated with chlorantraniliprole, produced mortality or abnormal behavior. Chlorantraniliprole is three orders of magnitude less acutely toxic to P. clarkii than lambda-cyhalothrin and etofenprox, two pyrethroid insecticides also used in rice, and is less likely to cause acute crayfish toxicity in rice pond ecosystems. Based on acute toxicity data, the use of chlorantraniliprole should be more compatible with rice-crayfish crop rotations than pyrethroids. (c) 2010 Society of Chemical Industry.

RNA-seq analysis of unintended effects in transgenic wheat overexpressing the transcription factor GmDREB1

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Qiyan Jiang

2017-06-01

Full Text Available The engineering of plants with enhanced tolerance to abiotic stresses typically involves complex multigene networks and may therefore have a greater potential to introduce unintended effects than the genetic modification for simple monogenic traits. For this reason, it is essential to study the unintended effects in transgenic plants engineered for stress tolerance. We selected drought- and salt-tolerant transgenic wheat overexpressing the transcription factor, GmDREB1, to investigate unintended pleiotropic effects using RNA-seq analysis. We compared the transcriptome alteration of transgenic plants with that of wild-type plants subjected to salt stress as a control. We found that GmDREB1 overexpression had a minimal impact on gene expression under normal conditions. GmDREB1 overexpression resulted in transcriptional reprogramming of the salt response, but many of the genes with differential expression are known to mitigate salt stress and contribute incrementally to the enhanced stress tolerance of transgenic wheat. GmDREB1 overexpression did not activate unintended gene networks with respect to gene expression in the roots of transgenic wheat. This work is important for establishing a method of detecting unintended effects of genetic engineering and the safety of such traits with the development of marketable transgenic crops in the near future.

Richness and density of aquatic benthic macroinvertebrates after exposure to fungicides and insecticides in rice paddy fields

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ALANA C.D. WANDSCHEER

Full Text Available ABSTRACT The objective of this study was to verify the richness and density of aquatic benthic macroinvertebrates after exposure to fungicides and insecticides of the rice paddy fields. In the crop seasons of 2012/13 and 2013/14, field experiments were performed, which consisted of single-dose applications of the fungicides trifloxystrobin + tebuconazole and tricyclazole, and the insecticides lambda-cyhalothrin + thiamethoxam and diflubenzuron, in 10 m2 experimental plots, over rice plants in the R3 stage. Control plots with and without rice plants were maintained in order to simulate a natural environment. Soil samples were collected during rice cultivation for assessment of the macroinvertebrate fauna. Chemical-physical parameters assessed in the experiments included temperature, pH and oxygen dissolved in the water and pesticide persistence in the water and in the soil. The application of a single dose of the pesticides and fungicides in the recommended period does not cause significant negative effects over the richness and density of the macroinvertebrates. Tebuconazole, tricyclazole and thiamethoxam showed high persistence in the irrigation water of rice paddy fields. Thus, the doses and number of applications of these products in crops should be carefully handled in order to avoid contamination of the environment.

Richness and density of aquatic benthic macroinvertebrates after exposure to fungicides and insecticides in rice paddy fields.

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Wandscheer, Alana C D; Marchesan, Enio; Santos, Sandro; Zanella, Renato; Silva, Marília F; Londero, Guilherme P; Donato, Gabriel

2017-01-01

The objective of this study was to verify the richness and density of aquatic benthic macroinvertebrates after exposure to fungicides and insecticides of the rice paddy fields. In the crop seasons of 2012/13 and 2013/14, field experiments were performed, which consisted of single-dose applications of the fungicides trifloxystrobin + tebuconazole and tricyclazole, and the insecticides lambda-cyhalothrin + thiamethoxam and diflubenzuron, in 10 m2 experimental plots, over rice plants in the R3 stage. Control plots with and without rice plants were maintained in order to simulate a natural environment. Soil samples were collected during rice cultivation for assessment of the macroinvertebrate fauna. Chemical-physical parameters assessed in the experiments included temperature, pH and oxygen dissolved in the water and pesticide persistence in the water and in the soil. The application of a single dose of the pesticides and fungicides in the recommended period does not cause significant negative effects over the richness and density of the macroinvertebrates. Tebuconazole, tricyclazole and thiamethoxam showed high persistence in the irrigation water of rice paddy fields. Thus, the doses and number of applications of these products in crops should be carefully handled in order to avoid contamination of the environment.

Comparative management of Chilo suppressalis (Walker) (Lepidoptera: Crambidae) by convenient pesticides and non-chemical practices in a double rice cropping system

OpenAIRE

M. N. Poor Amiri; Faramarz Alinia; Sohrab Imani, et al.

2017-01-01

The inclination of rice growers towards double cropping system in north of Iran has raised new concerns about the excessive release of broad-spectrum pesticides, particularly organophosphates, in the environment. In this study, the efficiency of three insecticides and an integrated pest management (IPM) program for management of the striped rice stem borer, Chilo suppressalis (Walker) (Lep: Crambidae), in double cropping system was investigated under field condition. According to the results,...

Analysis of T-DNA/Host-Plant DNA Junction Sequences in Single-Copy Transgenic Barley Lines

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Joanne G. Bartlett

2014-01-01

Full Text Available Sequencing across the junction between an integrated transfer DNA (T-DNA and a host plant genome provides two important pieces of information. The junctions themselves provide information regarding the proportion of T-DNA which has integrated into the host plant genome, whilst the transgene flanking sequences can be used to study the local genetic environment of the integrated transgene. In addition, this information is important in the safety assessment of GM crops and essential for GM traceability. In this study, a detailed analysis was carried out on the right-border T-DNA junction sequences of single-copy independent transgenic barley lines. T-DNA truncations at the right-border were found to be relatively common and affected 33.3% of the lines. In addition, 14.3% of lines had rearranged construct sequence after the right border break-point. An in depth analysis of the host-plant flanking sequences revealed that a significant proportion of the T-DNAs integrated into or close to known repetitive elements. However, this integration into repetitive DNA did not have a negative effect on transgene expression.

Transgenic biofortification of the starchy staple cassava (Manihot esculenta generates a novel sink for protein.

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Mohammad Abhary

Full Text Available Although calorie dense, the starchy, tuberous roots of cassava provide the lowest sources of dietary protein within the major staple food crops (Manihot esculenta Crantz. (Montagnac JA, Davis CR, Tanumihardjo SA. (2009 Compr Rev Food Sci Food Saf 8:181-194. Cassava was genetically modified to express zeolin, a nutritionally balanced storage protein under control of the patatin promoter. Transgenic plants accumulated zeolin within de novo protein bodies localized within the root storage tissues, resulting in total protein levels of 12.5% dry weight within this tissue, a fourfold increase compared to non-transgenic controls. No significant differences were seen for morphological or agronomic characteristics of transgenic and wild type plants in the greenhouse and field trials, but relative to controls, levels of cyanogenic compounds were reduced by up to 55% in both leaf and root tissues of transgenic plants. Data described here represent a proof of concept towards the potential transformation of cassava from a starchy staple, devoid of storage protein, to one capable of supplying inexpensive, plant-based proteins for food, feed and industrial applications.

Food safety knowledge on the Bt mutant protein Cry8Ka5 employed in the development of coleopteran-resistant transgenic cotton plants.

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Farias, Davi F; Peijnenburg, Ad A C M; Grossi-de-Sá, Maria F; Carvalho, Ana F U

2015-01-01

Insecticidal Cry proteins from Bacillus thuringiensis (Bt) have been exploited in the development of genetically modified (GM) crops for pest control. However, several pests are still difficult to control such as the coleopteran boll weevil Anthonomus grandis. By applying in vitro molecular evolution to the cry8Ka1 gene sequence, variants were generated with improved activity against A. grandis. Among them, Cry8Ka5 mutant protein showed coleoptericidal activity 3-fold higher (LC50 2.83 μg/mL) than that of the original protein (Cry8Ka1). Cry8Ka5 has been used in breeding programs in order to obtain coleopteran-resistant cotton plants. Nevertheless, there is some concern in relation to the food safety of transgenic crops, especially to the heterologously expressed proteins. In this context, our research group has performed risk assessment studies on Cry8Ka5, using the tests recommended by Codex as well as tests that we proposed as alternative and/or complementary approaches. Our results on the risk analysis of Cry8Ka5 taken together with those of other Cry proteins, point out that there is a high degree of certainty on their food safety. It is reasonable to emphasize that most safety studies on Cry proteins have essentially used the Codex approach. However, other methodologies would potentially provide additional information such as studies on the effects of Cry proteins and derived peptides on the indigenous gastrointestinal microbiota and on intestinal epithelial cells of humans. Additionally, emerging technologies such as toxicogenomics potentially will offer sensitive alternatives for some current approaches or methods.

Induced mutations and molecular techniques for crop improvement. Proceedings of an international symposium

International Nuclear Information System (INIS)

1995-01-01

The symposium was aimed at reviewing current aspects of mutation and molecular biology techniques for use in crop improvement and to bridge the gap between practical plant breeding and molecular laboratory techniques. Over the past few years, many transgenic plants have been developed in important crops such as rice, wheat, maize, soybean, banana, cassava and cotton, as well as in many food, industrial and pharmaceutical plant species. More than 180 participants from 48 countries of which 31 were from developing countries, attended which provided a forum for the discussion of problems related to crop improvement world wide, and their possible solutions. Refs, figs and tabs

Role of ethylene receptors during senescence and ripening in horticultural crops

Science.gov (United States)

Agarwal, Gaurav; Choudhary, Divya; Singh, Virendra P.; Arora, Ajay

2012-01-01

The past two decades have been rewarding in terms of deciphering the ethylene signal transduction and functional validation of the ethylene receptor and downstream genes involved in the cascade. Our knowledge of ethylene receptors and its signal transduction pathway provides us a robust platform where we can think of manipulating and regulating ethylene sensitivity by the use of genetic engineering and making transgenic. This review focuses on ethylene perception, receptor mediated regulation of ethylene biosynthesis, role of ethylene receptors in flower senescence, fruit ripening and other effects induced by ethylene. The expression behavior of the receptor and downstream molecules in climacteric and non climacteric crops is also elaborated upon. Possible strategies and recent advances in altering the ethylene sensitivity of plants using ethylene receptor genes in an attempt to modulate the regulation and sensitivity to ethylene have also been discussed. Not only will these transgenic plants be a boon to post-harvest physiology and crop improvement but, it will also help us in discovering the mechanism of regulation of ethylene sensitivity. PMID:22751331

Red rot resistant transgenic sugarcane developed through expression of β-1,3-glucanase gene.

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Shivani Nayyar

Full Text Available Sugarcane (Saccharum spp. is a commercially important crop, vulnerable to fungal disease red rot caused by Colletotrichum falcatum Went. The pathogen attacks sucrose accumulating parenchyma cells of cane stalk leading to severe losses in cane yield and sugar recovery. We report development of red rot resistant transgenic sugarcane through expression of β-1,3-glucanase gene from Trichoderma spp. The transgene integration and its expression were confirmed by quantitative reverse transcription-PCR in first clonal generation raised from T0 plants revealing up to 4.4-fold higher expression, in comparison to non-transgenic sugarcane. Bioassay of transgenic plants with two virulent C. falcatum pathotypes, Cf 08 and Cf 09 causing red rot disease demonstrated that some plants were resistant to Cf 08 and moderately resistant to Cf 09. The electron micrographs of sucrose storing stalk parenchyma cells from these plants displayed characteristic sucrose-filled cells inhibiting Cf 08 hyphae and lysis of Cf 09 hyphae; in contrast, the cells of susceptible plants were sucrose depleted and prone to both the pathotypes. The transgene expression was up-regulated (up to 2.0-fold in leaves and 5.0-fold in roots after infection, as compared to before infection in resistant plants. The transgene was successfully transmitted to second clonal generation raised from resistant transgenic plants. β-1,3-glucanase protein structural model revealed that active sites Glutamate 628 and Aspartate 569 of the catalytic domain acted as proton donor and nucleophile having role in cleaving β-1,3-glycosidic bonds and pathogen hyphal lysis.

Analysis of T-DNA integration and generative segregation in transgenic winter triticale (x Triticosecale Wittmack

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Hensel Goetz

2012-09-01

Full Text Available Abstract Background While the genetic transformation of the major cereal crops has become relatively routine, to date only a few reports were published on transgenic triticale, and robust data on T-DNA integration and segregation have not been available in this species. Results Here, we present a comprehensive analysis of stable transgenic winter triticale cv. Bogo carrying the selectable marker gene HYGROMYCIN PHOSPHOTRANSFERASE (HPT and a synthetic green fluorescent protein gene (gfp. Progeny of four independent transgenic plants were comprehensively investigated with regard to the number of integrated T-DNA copies, the number of plant genomic integration loci, the integrity and functionality of individual T-DNA copies, as well as the segregation of transgenes in T1 and T2 generations, which also enabled us to identify homozygous transgenic lines. The truncation of some integrated T-DNAs at their left end along with the occurrence of independent segregation of multiple T-DNAs unintendedly resulted in a single-copy segregant that is selectable marker-free and homozygous for the gfp gene. The heritable expression of gfp driven by the maize UBI-1 promoter was demonstrated by confocal laser scanning microscopy. Conclusions The used transformation method is a valuable tool for the genetic engineering of triticale. Here we show that comprehensive molecular analyses are required for the correct interpretation of phenotypic data collected from the transgenic plants.

Arabidopsis EF-Tu receptor enhances bacterial disease resistance in transgenic wheat.

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Schoonbeek, Henk-Jan; Wang, Hsi-Hua; Stefanato, Francesca L; Craze, Melanie; Bowden, Sarah; Wallington, Emma; Zipfel, Cyril; Ridout, Christopher J

2015-04-01

Perception of pathogen (or microbe)-associated molecular patterns (PAMPs/MAMPs) by pattern recognition receptors (PRRs) is a key component of plant innate immunity. The Arabidopsis PRR EF-Tu receptor (EFR) recognizes the bacterial PAMP elongation factor Tu (EF-Tu) and its derived peptide elf18. Previous work revealed that transgenic expression of AtEFR in Solanaceae confers elf18 responsiveness and broad-spectrum bacterial disease resistance. In this study, we developed a set of bioassays to study the activation of PAMP-triggered immunity (PTI) in wheat. We generated transgenic wheat (Triticum aestivum) plants expressing AtEFR driven by the constitutive rice actin promoter and tested their response to elf18. We show that transgenic expression of AtEFR in wheat confers recognition of elf18, as measured by the induction of immune marker genes and callose deposition. When challenged with the cereal bacterial pathogen Pseudomonas syringae pv. oryzae, transgenic EFR wheat lines had reduced lesion size and bacterial multiplication. These results demonstrate that AtEFR can be transferred successfully from dicot to monocot species, further revealing that immune signalling pathways are conserved across these distant phyla. As novel PRRs are identified, their transfer between plant families represents a useful strategy for enhancing resistance to pathogens in crops. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Insecticide-induced hormesis and arthropod pest management.

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Guedes, Raul Narciso C; Cutler, G Christopher

2014-05-01

Ecological backlashes such as insecticide resistance, resurgence and secondary pest outbreaks are frequent problems associated with insecticide use against arthropod pest species. The last two have been particularly important in sparking interest in the phenomenon of insecticide-induced hormesis within entomology and acarology. Hormesis describes a biphasic dose-response relationship that is characterized by a reversal of response between low and high doses of a stressor (e.g. insecticides). Although the concept of insecticide-induced hormesis often does not receive sufficient attention, or has been subject to semantic confusion, it has been reported in many arthropod pest species and natural enemies, and has been linked to pest outbreaks and potential problems with insecticide resistance. The study of hormesis remains largely neglected in entomology and acarology. Here, we examined the concept of insecticide-induced hormesis in arthropods, its functional basis and potential fitness consequences, and its importance in arthropod pest management and other areas. © 2013 Society of Chemical Industry.

Single-tube hydroponics as a novel idea for small-scale production of crop seed in a plant incubator.

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Kuroda, Masaharu; Ikenaga, Sachiko

2015-01-01

We present a novel protocol for small-scale production of crop seed in a plant incubator termed "Single-tube hydroponics." Our protocol minimizes the materials and methods for cultivation whereby a large number of independent plants can be cultured in a limited space. This study may aid in the improvement of crop seed components, especially in the cultivation of transgenic plants.

Organophosphate insecticide poisoning of Canada geese in the Texas panhandle

Science.gov (United States)

White, D.H.; Mitchell, C.A.; Wynn, L.D.; Flickinger, Edward L.; Kolbe, E.J.

1982-01-01

Sixteen hundred waterfowl, mostly Canada Geese, died near Etter, Texas, in late January 1981 from anticholinesterase poisoning. Winter wheat in the area of the die-off had been treated with organophosphate insecticides to control greenbugs. Cholinesterase (ChE) levels in brains of a sample of geese found dead were 75% below normal, enough to account for death (Ludke et al. 1975). The gastrointestinal (G I) tracts of geese found dead were packed with winter wheat; gas chromatography techniques identified parathion and methyl parathion in the GI tract contents. Residues of both chemicals were confirmed by mass spectrometry. We recommend that less toxic materials, such as malathion, be used on grain crops when waterfowl are in the vicinity of treatment.

Weevil x Insecticide: Does 'Personality' Matter?

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Morales, Juliana A; Cardoso, Danúbia G; Della Lucia, Terezinha Maria C; Guedes, Raul Narciso C

2013-01-01

An insect's behavior is the expression of its integrated physiology in response to external and internal stimuli, turning insect behavior into a potential determinant of insecticide exposure. Behavioral traits may therefore influence insecticide efficacy against insects, compromising the validity of standard bioassays of insecticide activity, which are fundamentally based on lethality alone. By extension, insect 'personality' (i.e., an individual's integrated set of behavioral tendencies that is inferred from multiple empirical measures) may also be an important determinant of insecticide exposure and activity. This has yet to be considered because the behavioral studies involving insects and insecticides focus on populations rather than on individuals. Even among studies of animal 'personality', the relative contributions of individual and population variation are usually neglected. Here, we assessed behavioral traits (within the categories: activity, boldness/shyness, and exploration/avoidance) of individuals from 15 populations of the maize weevil (Sitophilus zeamais), an important stored-grain pest with serious problems of insecticide resistance, and correlated the behavioral responses with the activity of the insecticide deltamethrin. This analysis was performed at both the population and individual levels. There was significant variation in weevil 'personality' among individuals and populations, but variation among individuals within populations accounted for most of the observed variation (92.57%). This result emphasizes the importance of individual variation in behavioral and 'personality' studies. When the behavioral traits assessed were correlated with median lethal time (LT50) at the population level and with the survival time under insecticide exposure, activity traits, particularly the distance walked, significantly increased survival time. Therefore, behavioral traits are important components of insecticide efficacy, and individual variation should be

Impact of transgenic soybean expressing Cry1Ac and Cry1F proteins on the non-target arthropod community associated with soybean in Brazil.

Science.gov (United States)

Marques, Luiz H; Santos, Antonio C; Castro, Boris A; Storer, Nicholas P; Babcock, Jonathan M; Lepping, Miles D; Sa, Verissimo; Moscardini, Valéria F; Rule, Dwain M; Fernandes, Odair A

2018-01-01

Field-scale studies that examine the potential for adverse effects of Bt crop technology on non-target arthropods may supplement data from laboratory studies to support an environmental risk assessment. A three year field study was conducted in Brazil to evaluate potential for adverse effects of cultivating soybean event DAS-81419-2 that produces the Cry1Ac and Cry1F proteins. To do so, we examined the diversity and abundance of non-target arthropods (NTAs) in Bt soybean in comparison with its non-Bt near isoline, with and without conventional insecticide applications, in three Brazilian soybean producing regions. Non-target arthropod abundance was surveyed using Moericke traps (yellow pan) and pitfall trapping. Total abundance (N), richness (S), Shannon-Wiener (H'), Simpson's (D) and Pielou's evenness (J) values for arthropod samples were calculated for each treatment and sampling period (soybean growth stages). A faunistic analysis was used to select the most representative NTAs which were used to describe the NTA community structure associated with soybean, and to test for effects due to the treatments effects via application of the Principal Response Curve (PRC) method. Across all years and sites, a total of 254,054 individuals from 190 taxa were collected by Moericke traps, while 29,813 individuals from 100 taxa were collected using pitfall traps. Across sites and sampling dates, the abundance and diversity measurements of representative NTAs were not significantly affected by Bt soybean as compared with non-sprayed non-Bt soybean. Similarly, community analyses and repeated measures ANOVA, when applicable, indicated that neither Bt soybean nor insecticide sprays altered the structure of the NTA communities under study. These results support the conclusion that transgenic soybean event DAS-81419-2 producing Cry1Ac and Cry1F toxins does not adversely affect the NTA community associated with soybean.

Estimated environmental loads of alpha-amylase from transgenic high-amylase maize

Energy Technology Data Exchange (ETDEWEB)

Wolt, Jeffrey D. [Department of Agronomy, Iowa State University, Ames, IA 50011 (United States); Biosafety Institute for Genetically Modified Agricultural Products, 164 Seed Science, Iowa State University, Ames, IA 50011 (United States); Karaman, Sule [Biosafety Institute for Genetically Modified Agricultural Products, 164 Seed Science, Iowa State University, Ames, IA 50011 (United States)

2007-11-15

Environmental exposure of plants bioengineered to improve efficiencies of biofuel production is an important consideration for their adoption. High-amylase maize genetically engineered to produce thermostable alpha-amylase in seed endosperm is currently in development, and its successful adoption will entail >1000 km{sup 2} of annual production in the USA. Environmental exposure of thermostable amylase will occur in production fields from preharvest and harvest dropped grain, with minor additional contributions from stover and root biomass. Mass loadings of thermostable alpha-amylase are projected to be 16 kg km{sup -2} and represent a potential source of increased alpha-amylase activity in receiving soils. An understanding of the degradation, persistence, accumulation, and activity of thermostable alpha-amylase introduced from transgenic high-amylase maize will be necessary in order to effectively manage transgenic crop systems intended or biofeedstock production. (author)

Dynamic plant uptake model applied for drip irrigation of an insecticide to pepper fruit plants.

Science.gov (United States)

Legind, Charlotte N; Kennedy, Coleen M; Rein, Arno; Snyder, Nathan; Trapp, Stefan

2011-05-01

Drip application of insecticides is an effective way to deliver the chemical to the plant that avoids off-site movement via spray drift and minimizes applicator exposure. The aim of this paper is to present a cascade model for the uptake of pesticide into plants following drip irrigation, its application for a soil-applied insecticide and a sensitivity analysis of the model parameters. The model predicted the measured increase and decline of residues following two soil applications of an insecticide to peppers, with an absolute error between model and measurement ranging from 0.002 to 0.034 mg kg fw(-1). Maximum measured concentrations in pepper fruit were approximately 0.22 mg kg fw(-1). Temperature was the most sensitive component for predicting the peak and final concentration in pepper fruit, through its influence on soil and plant degradation rates. Repeated simulations of pulse inputs with the cascade model adequately describe soil pesticide applications to an actual cropped system and reasonably mimic it. The model has the potential to be used for the optimization of practical features, such as application rates and waiting times between applications and before harvest, through the integrated accounting of soil, plant and environmental influences. Copyright © 2011 Society of Chemical Industry.

Erythritol, a non-nutritive sugar alcohol sweetener and the main component of truvia®, is a palatable ingested insecticide.

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Kaitlin M Baudier

Full Text Available Insecticides have a variety of commercial applications including urban pest control, agricultural use to increase crop yields, and prevention of proliferation of insect-borne diseases. Many pesticides in current use are synthetic molecules such as organochlorine and organophosphate compounds. Some synthetic insecticides suffer drawbacks including high production costs, concern over environmental sustainability, harmful effects on human health, targeting non-intended insect species, and the evolution of resistance among insect populations. Thus, there is a large worldwide need and demand for environmentally safe and effective insecticides. Here we show that Erythritol, a non-nutritive sugar alcohol, was toxic to the fruit fly Drosophila melanogaster. Ingested erythritol decreased fruit fly longevity in a dose-dependent manner, and erythritol was ingested by flies that had free access to control (sucrose foods in choice and CAFE studies. Erythritol was US FDA approved in 2001 and is used as a food additive in the United States. Our results demonstrate, for the first time, that erythritol may be used as a novel, environmentally sustainable and human safe approach for insect pest control.

The overexpression of insect endogenous small RNAs in transgenic rice inhibits growth and delays pupation of striped stem borer (Chilo suppressalis).

Science.gov (United States)

Jiang, Shan; Wu, Hao; Liu, Haoju; Zheng, Jie; Lin, Yongjun; Chen, Hao

2017-07-01

The striped stem borer (SSB), Chilo suppressalis Walker, is a major rice insect pest worldwide. RNA interference (RNAi) has become a promising strategy for developing insect-resistant crops. In a previous study, five double-stranded RNAs (dsRNAs) targeting important SSB housekeeping genes were overexpressed in rice, but none of the acquired dsRNA-transgenic rice plants showed significant effects on SSB. Thirteen selected SSB endogenous small RNAs, predicted as SSB novel microRNAs (miRNAs), were overexpressed in rice using artificial miRNA (amiRNA) expression technology. Feeding tests showed that two out of 13 selected SSB novel miRNAs caused significant growth inhibition for feeding SSB larvae based on transgenic rice expression. Pupation was delayed 4 days when SSB larvae consecutively fed on transgenic rice expressing the SSB novel miRNA candidate csu-novel-miR15 (csu-15 rice). Gene expression analysis confirmed that the expression levels of at least six SSB unigenes significantly changed (i.e., were up- or down-regulated) after feeding on csu-15 rice. Our research demonstrated a novel RNAi strategy using SSB endogenous small RNAs to develop RNAi crops for pest management; this strategy is different from the common RNAi resulting from transgenic dsRNAs or amiRNAs targeting certain insect endogenous genes. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Carboxylesterase activities toward pesticide esters in crops and weeds.

Science.gov (United States)

Gershater, Markus; Sharples, Kate; Edwards, Robert

2006-12-01

Proteins were extracted from maize, rice, sorghum, soybean, flax and lucerne; the weeds Abutilon theophrasti, Echinochloa crus-galli, Phalaris canariensis, Setaria faberii, Setaria viridis, Sorghum halepense and the model plant Arabidopsis thaliana and assayed for carboxylesterase activity toward a range of xenobiotics. These included the pro-herbicidal esters clodinafop-propargyl, fenoxaprop-ethyl, fenthioprop-ethyl, methyl-2,4-dichlorophenoxyacetic acid (2,4-d-methyl), bromoxynil-octanoate, the herbicide-safener cloquintocet-mexyl and the pyrethroid insecticide permethrin. Highest activities were recorded with alpha-naphthyl acetate and methylumbelliferyl acetate. Esters of p-nitrophenol were also readily hydrolysed, with turnover declining as the chain length of the acyl component increased. Activities determined with model substrates were much higher than those observed with pesticide esters and were of limited value in predicting the relative rates of hydrolysis of the crop protection agents. Substrate preferences with the herbicides were typically 2,4-d-methyl>clodinafop-propargyl>fenthioprop-ethyl, fenoxaprop-ethyl and bromoxynil-octanoate. Isoelectric focussing in conjunction with staining for esterase activity using alpha-naphthyl acetate as substrate confirmed the presence of multiple carboxylesterase isoenzymes in each plant, with major qualitative differences observed between species. The presence of serine hydrolases among the resolved isoenzymes was confirmed through their selective inhibition by the organophosphate insecticide paraoxon. Our studies identify potentially exploitable differences between crops and weeds in their ability to bioactivate herbicides by enzymic hydrolysis and also highlight the usefulness of Arabidopsis as a plant model to study xenobiotic biotransformation.

Monitoring of the insecticide trichlorfon by phosphorus-31 nuclear magnetic resonance (31P NMR) spectroscopy

International Nuclear Information System (INIS)

Talebpour, Zahra; Ghassempour, Alireza; Zendehzaban, Mehdi; Bijanzadeh, Hamid Reza; Mirjalili, Mohammad Hossein

2006-01-01

Trichlorfon is an organophosphorus insecticide, which is extensively being used for protection of fruit crops. Trichlorfon is a thermal labile compound, which cannot be easily determined by gas chromatography (GC) and has no suitable group for sensitive detection by high performance liquid chromatography (HPLC). In this study, a 31 P nuclear magnetic resonance ( 31 P NMR) has been described for monitoring of trichlorfon without any separation step. The quantitative works of 31 P NMR spectroscopy has been performed in the presence of an internal standard (hexamethylphosphoramide). Limit of detection (LOD) for this method has been found to be 55 mg L -1 , without any sample preparation, and the linear working range was 150-5500 mg L -1 . Relative standard deviation (R.S.D.%) of the method for three replicates within and between days was obtained ≤9%. The average recovery efficiency was approximately 99-112%. This method was applied for monitoring trichlorfon in a commercial insecticide sample and tomato sample

Antifungal genes expressed in transgenic pea (Pisum sativum L.) do not affect root colonization of arbuscular mycorrhizae fungi.

Science.gov (United States)

Kahlon, Jagroop Gill; Jacobsen, Hans-Jörg; Cahill, James F; Hall, Linda M

2017-10-01

Genetically modified crops have raised concerns about unintended consequences on non-target organisms including beneficial soil associates. Pea transformed with four antifungal genes 1-3 β glucanase, endochitinase, polygalacturonase-inhibiting proteins, and stilbene synthase is currently under field-testing for efficacy against fungal diseases in Canada. Transgenes had lower expression in the roots than leaves in greenhouse experiment. To determine the impact of disease-tolerant pea or gene products on colonization by non-target arbuscular mycorrhizae and nodulation by rhizobium, a field trial was established. Transgene insertion, as single gene or stacked genes, did not alter root colonization by arbuscular mycorrhiza fungus (AMF) or root nodulation by rhizobium inoculation in the field. We found no effect of transgenes on the plant growth and performance although, having a dual inoculant with both AMF and rhizobium yielded higher fresh weight shoot-to-root ratio in all the lines tested. This initial risk assessment of transgenic peas expressing antifungal genes showed no deleterious effect on non-target organisms.

The impacts of the transgenes on the modified crops, non-target soil ...

African Journals Online (AJOL)

Yomi

reduction of emission of greenhouse gases, caused several changes in the modified crop plants, interacted with soil ...... fitness and behaviour of monarch butterfly larvae exposed to a combination of ..... climate change hypothesis. Am. Antiq.

Expression of the Arabidopsis vacuolar H+-pyrophosphatase gene (AVP1) improves the shoot biomass of transgenic barley and increases grain yield in a saline field

KAUST Repository

Schilling, Rhiannon K.

2013-11-22

Cereal varieties with improved salinity tolerance are needed to achieve profitable grain yields in saline soils. The expression of AVP1, an Arabidopsis gene encoding a vacuolar proton pumping pyrophosphatase (H+-PPase), has been shown to improve the salinity tolerance of transgenic plants in greenhouse conditions. However, the potential for this gene to improve the grain yield of cereal crops in a saline field has yet to be evaluated. Recent advances in high-throughput nondestructive phenotyping technologies also offer an opportunity to quantitatively evaluate the growth of transgenic plants under abiotic stress through time. In this study, the growth of transgenic barley expressing AVP1 was evaluated under saline conditions in a pot experiment using nondestructive plant imaging and in a saline field trial. Greenhouse-grown transgenic barley expressing AVP1 produced a larger shoot biomass compared to segregants, as determined by an increase in projected shoot area, when grown in soil with 150 mm NaCl. This increase in shoot biomass of transgenic AVP1 barley occurred from an early growth stage and also in nonsaline conditions. In a saline field, the transgenic barley expressing AVP1 also showed an increase in shoot biomass and, importantly, produced a greater grain yield per plant compared to wild-type plants. Interestingly, the expression of AVP1 did not alter barley leaf sodium concentrations in either greenhouse- or field-grown plants. This study validates our greenhouse-based experiments and indicates that transgenic barley expressing AVP1 is a promising option for increasing cereal crop productivity in saline fields. © 2013 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

Expression of the Arabidopsis vacuolar H+-pyrophosphatase gene (AVP1) improves the shoot biomass of transgenic barley and increases grain yield in a saline field

KAUST Repository

Schilling, Rhiannon K.; Marschner, Petra; Shavrukov, Yuri N.; Berger, Bettina; Tester, Mark A.; Roy, Stuart John; Plett, Darren Craig

2013-01-01

Cereal varieties with improved salinity tolerance are needed to achieve profitable grain yields in saline soils. The expression of AVP1, an Arabidopsis gene encoding a vacuolar proton pumping pyrophosphatase (H+-PPase), has been shown to improve the salinity tolerance of transgenic plants in greenhouse conditions. However, the potential for this gene to improve the grain yield of cereal crops in a saline field has yet to be evaluated. Recent advances in high-throughput nondestructive phenotyping technologies also offer an opportunity to quantitatively evaluate the growth of transgenic plants under abiotic stress through time. In this study, the growth of transgenic barley expressing AVP1 was evaluated under saline conditions in a pot experiment using nondestructive plant imaging and in a saline field trial. Greenhouse-grown transgenic barley expressing AVP1 produced a larger shoot biomass compared to segregants, as determined by an increase in projected shoot area, when grown in soil with 150 mm NaCl. This increase in shoot biomass of transgenic AVP1 barley occurred from an early growth stage and also in nonsaline conditions. In a saline field, the transgenic barley expressing AVP1 also showed an increase in shoot biomass and, importantly, produced a greater grain yield per plant compared to wild-type plants. Interestingly, the expression of AVP1 did not alter barley leaf sodium concentrations in either greenhouse- or field-grown plants. This study validates our greenhouse-based experiments and indicates that transgenic barley expressing AVP1 is a promising option for increasing cereal crop productivity in saline fields. © 2013 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

Malaria Vector Control Still Matters despite Insecticide Resistance.

Science.gov (United States)

Alout, Haoues; Labbé, Pierrick; Chandre, Fabrice; Cohuet, Anna

2017-08-01

Mosquito vectors' resistance to insecticides is usually considered a major threat to the recent progresses in malaria control. However, studies measuring the impact of interventions and insecticide resistance reveal inconsistencies when using entomological versus epidemiological indices. First, evaluation tests that do not reflect the susceptibility of mosquitoes when they are infectious may underestimate insecticide efficacy. Moreover, interactions between insecticide resistance and vectorial capacity reveal nonintuitive outcomes of interventions. Therefore, considering ecological interactions between vector, parasite, and environment highlights that the impact of insecticide resistance on the malaria burden is not straightforward and we suggest that vector control still matters despite insecticide resistance. Copyright © 2017 Elsevier Ltd. All rights reserved.

TOXICITY OF INSECTICIDES USED IN MUSKMELON ON FIRST-INSTAR LARVAE OF Chrysoperla genanigra FREITAS (NEUROPTERA: CHRYSOPIDAE)

OpenAIRE

SILVA, BÁRBARA KARINE DE ALBUQUERQUE; GODOY, MAURÍCIO SEKIGUCHI DE; LIMA, ALRICÉLIA GOMES DE; OLIVEIRA, ANNA KÉZIA SOARES DE; PASTORI, PATRIK LUIZ

2017-01-01

ABSTRACT Brazil is one of the world's largest producers of melon (Cucumis melo L.), and Rio Grande do Norte and Ceará are the largest producers states of the country (99% of exports). This crop had great socio- economic importance in the Brazilian Northeast, however, it is affected by insect pests and consequently, large amounts of pesticides are applied to it, which greatly affect beneficial organisms, such as Chrysopidae. This bioassay evaluated the toxicity of nine insecticides used in com...

A renaissance for botanical insecticides?

Science.gov (United States)

Isman, Murray B

2015-12-01

Botanical insecticides continue to be a subject of keen interest among the international research community, reflected in the steady growth in scientific publications devoted to the subject. Until very recently though, the translation of that theory to practice, i.e. the commercialisation and adoption of new botanical insecticides in the marketplace, has seriously lagged behind. Strict regulatory regimes, long the bane of small pesticide producers, are beginning to relax some of the data requirements for 'low-risk' pesticide products, facilitating movement of more botanicals into the commercial arena. In this paper I discuss some of the jurisdictions where botanicals are increasingly finding favour, some of the newer botanical insecticides in the plant and animal health arsenal and some of the specific sectors where botanicals are most likely to compete effectively with other types of insecticidal product. © 2015 Society of Chemical Industry.

Modeling global distribution of agricultural insecticides in surface waters

International Nuclear Information System (INIS)

Ippolito, Alessio; Kattwinkel, Mira; Rasmussen, Jes J.; Schäfer, Ralf B.; Fornaroli, Riccardo; Liess, Matthias

2015-01-01

Agricultural insecticides constitute a major driver of animal biodiversity loss in freshwater ecosystems. However, the global extent of their effects and the spatial extent of exposure remain largely unknown. We applied a spatially explicit model to estimate the potential for agricultural insecticide runoff into streams. Water bodies within 40% of the global land surface were at risk of insecticide runoff. We separated the influence of natural factors and variables under human control determining insecticide runoff. In the northern hemisphere, insecticide runoff presented a latitudinal gradient mainly driven by insecticide application rate; in the southern hemisphere, a combination of daily rainfall intensity, terrain slope, agricultural intensity and insecticide application rate determined the process. The model predicted the upper limit of observed insecticide exposure measured in water bodies (n = 82) in five different countries reasonably well. The study provides a global map of hotspots for insecticide contamination guiding future freshwater management and conservation efforts. - Highlights: • First global map on insecticide runoff through modelling. • Model predicts upper limit of insecticide exposure when compared to field data. • Water bodies in 40% of global land surface may be at risk of adverse effects. • Insecticide application rate, terrain slope and rainfall main drivers of exposure. - We provide the first global map on insecticide runoff to surface water predicting that water bodies in 40% of global land surface may be at risk of adverse effects

Plasma cholinesterase inhibition in the clay-colored robin (Turdus grayi) exposed to diazinon in maradol papaya crops in Yucatan, Mexico

Science.gov (United States)

Cobos, V.M.; Mora, M.A.; Escalona, G.