Non-transgenic Varieties Research Articles

Discrimination of maize transgenic and non-transgenic varieties by laser induced spectroscopy (LIBS) and machine learning algorithms

BackgroundIn the last decades, the production and consumption of genetically modified agricultural products have increased markedly due to the worldwide population growth and rising demand for food and feed. Consequently, genetically modified crops have been extensively produced and consumed, which required identifying and discriminating transgenic and non-transgenic products. ResultsLaser-induced breakdown spectroscopy (LIBS) combined with chemometric methods was applied to identify and discriminate two varieties of conventional (not-genetically modified, NGM) maize from four varieties of transgenic maize (genetically modified, GM). The LIBS spectra acquired under reduced pressure (100 Torr) conditions over two ranges, i.e., 175–330 nm and 275–770 nm, were subjected to Standard Normal Variation (SNV) and multivariate methods such as Principal Component Analysis (PCA) to reduce data matrices dimensionality and spectral noise. The supervised machine learning algorithms k-nearest neighbor (k-NN) and support vector machine (SVM) have been applied to discriminate among NGM and GM maize reserving 25 % of data for external validation. The training data were employed for hyperparameter optimization of classifiers using the Leave-One-Out Cross-Validation (LOOCV) method. Considering all six maize varieties simultaneously, the highest training accuracy achieved was 90.56 %, with an external validation accuracy of 88.33 %. In an alternative approach based on pairwise combinations of one GM variety against one NGM variety, the best outcome achieved was 100 % LOOCV and external validation accuracy. ConclusionsThese results showed that LIBS supported by appropriate chemometric methods represents an alternative screening technique for identifying and discriminating transgenic from non-transgenic maize.

Evolving role of synthetic cytokinin 6-benzyl adenine for drought stress tolerance in soybean (Glycine max L. Merr.)

The enhanced growth and productivity of soybeans during the past decades were possible due to the application of agrichemicals such as bio-fertilizers, chemical fertilizers, and the use of high yielding, as well as disease resistant transgenic and non-transgenic varieties. Agrichemicals applied as seed primers, plant protectants, and growth regulators, however, had a diminutive significance on growth and productivity improvements across the globe. The utilization of plant growth regulators (PGRs) for vegetative growth, reproduction and yield quality improvements remains unexplored, particularly, the use of cytokinins such as 6-benzyl adenine (6-BAP) to improve soybean response to abiotic stresses. Therefore, an understanding of the role of 6-BAP in the mediation of an array of adaptive responses that provide plants with the ability to withstand abiotic stresses must be thoroughly investigated. Such mitigative effects will play a critical role in encouraging exogenous application of plant hormones like 6-BAP as a mechanism for overcoming drought stress related effects in soybean. This paper discusses the evolving role of synthetic cytokinin 6-bezyl adenine in horticulture, especially the implications of its exogenous applications in soybean to confer tolerance to drought stress.

Untargeted Proteomics-Based Approach to Investigate Unintended Changes in Genetically Modified Maize for Environmental Risk Assessment Purpose.

Profiling technologies, such as proteomics, allow the simultaneous measurement and comparison of thousands of plant components without prior knowledge of their identity. The combination of these non-targeted methods facilitates a more comprehensive approach than targeted methods and thus provides additional opportunities to identify genotypic changes resulting from genetic modification, including new allergens or toxins. The purpose of this study was to investigate unintended changes in GM Bt maize grown in South Africa. In the present study, we used bi-dimensional gel electrophoresis based on fluorescence staining, coupled with mass spectrometry in order to compare the proteome of the field-grown transgenic hybrid (MON810) and its near-isogenic counterpart. Proteomic data showed that energy metabolism and redox homeostasis were unequally modulated in GM Bt and non-GM maize variety samples. In addition, a potential allergenic protein—pathogenesis related protein −1 has been identified in our sample set. Our data shows that the GM variety is not substantially equivalent to its non-transgenic near-isogenic variety and further studies should be conducted in order to address the biological relevance and the potential risks of such changes. These finding highlight the suitability of unbiased profiling approaches to complement current GMO risk assessment practices worldwide.

Resveratrol-enriched rice identical to original Dongjin rice variety with respect to major agronomic traits in different cultivation years and regions

ABSTRACT Resveratrol is synthesized by the catalysis of resveratrol synthases (RS) in a limited number of higher plants. Resveratrol shows potential health-promoting properties, including as an antioxidant and in preventing cardiovascular diseases. Recently, resveratrol-enriched rice has been produced as a novel source of resveratrol. This study aimed to investigate the major agronomic characteristics of resveratrol-enriched rice, Iksan526 (I526) and compared them with those of a nontransgenic and commercial rice variety, Dongjin (DJ). Transgene (RS) integration was confirmed using Southern blot analysis, and homologous recombination was achieved after digestion with the SacI restriction enzyme. The phenotypic traits of I526 grown in Iksan were similar to those grown in Milyang but not similar to those grown in Suwon. In Suwon, I526 had slightly earlier heading dates [i.e., number of days from sowing to heading) and shorter culm lengths. When I526 was treated with 0.4% Basta in the seedling stage, no significant difference was observed among all the agronomic traits compared with nontreated I526; particularly, the culm length, panicle length, number of panicles per hill, 1,000 grain weight of brown rice, and brown rice yield of the Basta-treated rice were similar to those of the nontreated I526, regardless of their cultivation region. The resveratrol content of I526 grown in Suwon and Milyang was increased by 18% and 37%, respectively, than that of I526 grown in the Iksan area. Therefore, DJ and I526 are not significantly different in terms of major agronomic traits depending on variety/year and variety/cultivation region. The results indicated that I526 has the potential to become a commercialized variety in the near future.

Identification and integrated analysis of glyphosate stress-responsive microRNAs, lncRNAs, and mRNAs in rice using genome-wide high-throughput sequencing

BackgroundGlyphosate has become the most widely used herbicide in the world. Therefore, the development of new varieties of glyphosate-tolerant crops is a research focus of seed companies and researchers. The glyphosate stress-responsive genes were used for the development of genetically modified crops, while only the EPSPS gene has been used currently in the study on glyphosate-tolerance in rice. Therefore, it is essential and crucial to intensify the exploration of glyphosate stress-responsive genes, to not only acquire other glyphosate stress-responsive genes with clean intellectual property rights but also obtain non-transgenic glyphosate-tolerant rice varieties. This study is expected to elucidate the responses of miRNAs, lncRNAs, and mRNAs to glyphosate applications and the potential regulatory mechanisms in response to glyphosate stress in rice.ResultsLeaves of the non-transgenic glyphosate-tolerant germplasm CA21 sprayed with 2 mg·ml− 1 glyphosate (GLY) and CA21 plants with no spray (CK) were collected for high-throughput sequencing analysis. A total of 1197 DEGs, 131 DELs, and 52 DEMs were identified in the GLY samples in relation to CK samples. Genes were significantly enriched for various biological processes involved in detoxification of plant response to stress. A total of 385 known miRNAs from 59 miRNA families and 94 novel miRNAs were identified. Degradome analysis led to the identification of 32 target genes, of which, the squamosa promoter-binding-like protein 12 (SPL12) was identified as a target of osa-miR156a_L + 1. The lncRNA-miRNA-mRNA regulatory network consisted of osa-miR156a_L + 1, two transcripts of SPL12 (LOC_Os06g49010.3 and LOC_Os06g49010.5), and 13 lncRNAs (e.g., MSTRG.244.1 and MSTRG.16577.1).ConclusionLarge-scale expression changes in coding and noncoding RNA were observed in rice mainly due to its response to glyphosate. SPL12, osa-miR156, and lncRNAs (e.g., MSTRG.244.1 and MSTRG.16577.1) could be a novel ceRNA mechanism in response to glyphosate in rice by regulating transcription and metal ions binding. These findings provide a theoretical basis for breeding glyphosate-tolerant rice varieties and for further research on the biogenesis of glyphosate- tolerance in rice.

A Modified SDS – Based Method Applied for Extraction of High-Quality DNA from Raw Corn and Roasted Soybean

Abstract The probability of contamination of non-transgenic varieties with genetically modified (GM) products increase as a result of global expansion of areas sown with transgenic crops. DNA-based methods as accurate, efficient and reliable methods are preferable for detection of GM material in raw or highly processed foods. Isolation of high quality DNA with a suitable and efficient DNA extraction protocol is crucial for getting precise results in DNA amplification. In this study, we performed modifications of previously known Sodium dodecyl sulfate (SDS)-based DNA extraction method regarding the incubation period, DNA pellet washing and addition of organic solvent extraction, to improve DNA quality and to reduce costs. Raw corn kernels and roasted soybean seed were used as samples. DNA was extracted following three protocols, modifications of Edwards protocol. The type of detergent used in raw corn sample did not cause significant effects on extracted DNA yield and purity, while in roasted soybean samples the 2% (w/v) SDS lysis buffer gave the highest DNA yield. The additional incubation step raised the DNA yield from raw corn for 121%, while the purest DNA from soybean sample was obtained using organic solvent extraction. Electrophoretic determination of DNA integrity showed varying degree of DNA smearing from roasted soybean. Contrary, all extraction protocols used on raw corn kernels produced a high molecular weight DNA. Thus, our in-house DNA extraction protocol is as efficient but more cost effective compared to commercial kits and can be used for raw corn, while the protocol for roasted soybean needs further improvement.

Transformation and Evaluation of Cry1Ac+Cry2A and GTGene in Gossypium hirsutum L.

More than 50 countries around the globe cultivate cotton on a large scale. It is a major cash crop of Pakistan and is considered “white gold” because it is highly important to the economy of Pakistan. In addition to its importance, cotton cultivation faces several problems, such as insect pests, weeds, and viruses. In the past, insects have been controlled by insecticides, but this method caused a severe loss to the economy. However, conventional breeding methods have provided considerable breakthroughs in the improvement of cotton, but it also has several limitations. In comparison with conventional methods, biotechnology has the potential to create genetically modified plants that are environmentally safe and economically viable. In this study, a local cotton variety VH 289 was transformed with two Bt genes (Cry1Ac and Cry2A) and a herbicide resistant gene (cp4 EPSPS) using the Agrobacterium mediated transformation method. The constitutive CaMV 35S promoter was attached to the genes taken from Bacillus thuringiensis (Bt) and to an herbicide resistant gene during cloning, and this promoter was used for the expression of the genes in cotton plants. This construct was used to develop the Glyphosate Tolerance Gene (GTGene) for herbicide tolerance and insecticidal gene (Cry1Ac and Cry2A) for insect tolerance in the cotton variety VH 289. The transgenic cotton variety performed 85% better compared with the non-transgenic variety. The study results suggest that farmers should use the transgenic cotton variety for general cultivation to improve the production of cotton.

Mining for Glyphosate-Resistant Genes in Rice Genotypes of the Philippines

This study aimed to identify and characterize rice genotypes possibly possessing glyphosate-resistant genes, promoting the ability to withstand non-selective, systemic herbicides. The field establishment was based on alpha lattice design replicated into two with a plot size of 2 x 10 rows. All crop management practices followed the PalayCheck System®. At 14 DAT, the glyphosate-based herbicide (Round-up) was directly applied in rice plants. Survival and severity percentage were recorded from 4days to 20 days after herbicide application when the rice plants were observed reacting to the application while agronomic parameters were gathered at maturity stage. Out of one hundred rice genotypes, only 12 exhibited moderate to strong resistance to glyphosate-based herbicide while other genotypes stunted and wilted to death. The 12 genotypes are as follows: Kinastila, Binundor, Dinorado, Kalipao, Inanod, Camoros, Minondoc, Innano, Zambales, Maliket (Red), Kilay, and Simmaba. Among these twelve genotypes, Zambales is the most tolerant to glyphosate herbicide with highest survival rate and low severity index followed by Kalipao, Innaano and Kilay which have moderate survival rate and low severity rate. Identified resistant genotypes were agro-morphological characterized. Zambales genotype has the tallest plant height and highest spikelet number while the superior genotypes for the number of productive tillers, panicle length and spikelet fertility were Minondoc, Simmaba and Kinastila, respectively. These results show that the genotypes being tested have a wide variation in agro-morphological traits. Ultimately, 12 genotypes were identified as tolerant to glyphosate-based herbicide. Further evaluation and characterization are still required to verify the resistance of identified genotypes. These germplasms are promising materials for future breeding and research purposes in developing non-transgenic glyphosate-resistant rice varieties. Keywords-Genotypes, glyphosate resistance, morphological diversity, severity index, Philippines

GM plants with RNAi - golden mosaic resistant bean

GM plants with RNAi - golden mosaic resistant bean

Impact of β-carotene transgenic rice with four synthetic genes on rhizosphere enzyme activities and bacterial communities at different growth stages

A field experiment was carried out to assess the impact of β-carotene transgenic rice with four synthetic genes on bacterial communities and enzyme activities in the rhizosphere. Soil samples from two neighboring fields cultivated with transgenic rice AH33 and its parental non-transgenic variety Zhonghua 11 were taken at seedling, tillering, heading and maturing stages. There were no significant differences in activities of catalase, sucrase and protease between AH33 and Zhonghua 11 at the same growth stage. Although soil urease activities of AH33 showed significant differences (P < 0.05) compared with that of Zhonghua 11 at the heading stage, these differences were transient and disappeared at other stages, indicating that changes in soil enzyme activities were mainly related to plant age. Changes in the bacterial communities throughout different growth stages were monitored and analyzed using denaturing gradient gel electrophoresis (DGGE) and 16S rRNA gene clone library techniques. The resulting dendrograms of DGGE patterns showed four distinct clusters, which were identified to be correlating with the respective growth stages. No effect of the transgenic rice AH33 on dominant bacterial communities at the same growth stage was detectable. This indicated that the impact of crop growth stage outweighed possible alterations due to the genetic modifications. The analyses of DGGE and 16S rRNA gene clone libraries revealed that there were no significant differences (P < 0.05) in the Shannon–Wiener diversity index (H'), richness (R), and evenness (E) of rhizosphere soil between AH33 and Zhonghua 11 at any of the stages. Thus, there was no indication of altered overall bacterial diversity due to the genetic modification. Sequencing of PCR amplicons indicated that the DGGE profiles were mainly composed of Proteobacteria, Acidobacteria, Gemmatimonadetes, Chloroflexi and Verrucomicrobia, and in addition, the 16S rRNA gene clone libraries indicated the presence of Plantomycetes, Armatimonadetes, Actinobacteria, Chlorobi, Cyanobacteria and Fimicutes. In conclusion, our study based on the analysis of four different soil enzymes and the diversity of rhizosphere bacteria gives no indication that the genetic modification with the four synthetic genes and their expression in the transgenic rice AH33 has any specific effects, related to the genetic modification, on the soils in which they are cultivated.

Impact of barley (Hordeum vulgare L.) transgenic line H228.2A on substrate and rhizosphere microorganisms and the possibility of horizontal gene transfer

Numerous investigations have been carried out to determine the impact of genetically modified plants, such as potato, maize, alfalfa and tobacco, on soil microorganisms and the results are contradictory. We applied classical microbiology methods to study quantitative changes of bacterial and fungal abundance in substrate and rhizosphere from barley (Hordeum vulgare L.) transgenic line H228.2A containing Rpg1 and bar genes, and its parent nontransgenic variety ‘Golden Promise’. In addition, molecular biology methods were used to determine, if horizontal gene transfer from barley transgenic line to soil bacteria has occurred under experimental conditions by screening bacterial genomes for the presence of Rpg1 gene sequences using polymerase chain reactions. Results did not show significant impact on substrate and rhizosphere microorganisms. In the second pot experiment the average number of filamentous fungi in the rhizosphere of parent line ‘Golden Promise’ was higher than in the rhizosphere of transgenic line, but the variation among samples was very high probably caused by the high variation of substrate moisture content. None of bacterial deoxyribonucleic acid (DNA) samples isolated from substrate of rhizosphere of barley transgenic line resulted in positive amplification of Rpg1 gene-specific primer product.

Agronomic Performance of Transgenic and Non Trangenic Cotton against Cotton Leaf Curl Virus

The present study was carried out to increase the level of tolerance in Gossypium hirsutum L. against cotton leaf curl disease (CLCuD). Hybridization of a transgenic line (anti-sense tRep gene) with three naturally resistant (non-transgenic) varieties namely FH-1000, MNH-786 and NIBGE-115 was performed. The parents and their F1 Hybrids were evaluated for disease infectivity. Data of some morphological traits (Plant Height, Monopodial Branches per Plant, Sympodial Branches per Plant, Number of Boll per Plant, Lint Percentage, Boll Weight, Staple Length, Staple Strength, Fiber Fineness, Yield of Seed Cotton ) was evaluated satanically to check the influence of disease on morphology of plant. The results showed that hybridization increased the tolerance level against cotton leaf curl virus.

Deep sequencing uncovers commonality in small RNA profiles between transgene-induced and naturally occurring RNA silencing of chalcone synthase-A gene in petunia

BackgroundIntroduction of a transgene that transcribes RNA homologous to an endogenous gene in the plant genome can induce silencing of both genes, a phenomenon termed cosuppression. Cosuppression was first discovered in transgenic petunia plants transformed with the CHS-A gene encoding chalcone synthase, in which nonpigmented sectors in flowers or completely white flowers are produced. Some of the flower-color patterns observed in transgenic petunias having CHS-A cosuppression resemble those in existing nontransgenic varieties. Although the mechanism by which white sectors are generated in nontransgenic petunia is known to be due to RNA silencing of the CHS-A gene as in cosuppression, whether the same trigger(s) and/or pattern of RNA degradation are involved in these phenomena has not been known. Here, we addressed this question using deep-sequencing and bioinformatic analyses of small RNAs.ResultsWe analyzed short interfering RNAs (siRNAs) produced in nonpigmented sectors of petal tissues in transgenic petunia plants that have CHS-A cosuppression and a nontransgenic petunia variety Red Star, that has naturally occurring CHS-A RNA silencing. In both silencing systems, 21-nt and 22-nt siRNAs were the most and the second-most abundant size classes, respectively. CHS-A siRNA production was confined to exon 2, indicating that RNA degradation through the RNA silencing pathway occurred in this exon. Common siRNAs were detected in cosuppression and naturally occurring RNA silencing, and their ranks based on the number of siRNAs in these plants were correlated with each other. Noticeably, highly abundant siRNAs were common in these systems. Phased siRNAs were detected in multiple phases at multiple sites, and some of the ends of the regions that produced phased siRNAs were conserved.ConclusionsThe features of siRNA production found to be common to cosuppression and naturally occurring silencing of the CHS-A gene indicate mechanistic similarities between these silencing systems especially in the biosynthetic processes of siRNAs including cleavage of CHS-A transcripts and subsequent production of secondary siRNAs in exon 2. The data also suggest that these events occurred at multiple sites, which can be a feature of these silencing phenomena.

Dominos in the dairy: An analysis of transgenic maize in Dutch dairy farming

EU member states require farmers growing transgenic maize to respect a minimum distance from fields with non-transgenic maize. Previous studies have theoretically argued that such minimum distance requirements may lead to a so-called ‘domino effect’ where farmers who want to grow transgenic maize are forced to grow the non-transgenic variety and in turn impose the same constraints on their neighbors. This article applies a spatially explicit farm model to a dairy region in the Southern Netherlands to assess how farmers growing non-transgenic maize limit other farmers' potential to grow transgenic herbicide-resistant maize. The results indicate that the minimum distance requirements can severely limit the benefits from herbicide resistant maize. Having different land use options in one farm, however, enables dairy farmers to grow transgenic maize despite having one or more neighbors growing non-transgenic maize. We also find that the share of the domino effect in the overall impact of minimum distance requirements decreases with the density of farmers not growing transgenic maize.

Improving nontransgenic crop varieties with plant transformation approaches

Improving nontransgenic crop varieties with plant transformation approaches

Improving nontransgenic crop varieties with plant transformation approaches

Improving nontransgenic crop varieties with plant transformation approaches

Metabolite profiles of rice cultivars containing bacterial blight-resistant genes are distinctive from susceptible rice

The metabolic changes of bacterial blight-resistant line C418/Xa23 generated by molecular marker-assisted selection (n= 12), transgenic variety C418-Xa21 generated by using the Agrobacterium-mediated system (n= 12), and progenitor cultivar C418 (n= 12) were monitored using gas chromatography/mass spectrometry. The validation, discrimination, and establishment of correlative relationships between metabolite signals were performed by cluster analysis, principal component analysis, and partial least squares-discriminant analysis. Significant and unintended changes were observed in 154 components in C418/Xa23 and 48 components in C418-Xa21 compared with C418 (P< 0.05, Fold change > 2.0). The most significant decreases detected (P< 0.001) in both C418/Xa23 and C418-Xa21 were in three amino acids: glycine, tyrosine, and alanine, and four identified metabolites: malic acid, ferulic acid, succinic acid, and glycerol. Linoleic acid was increased specifically in C418/Xa23 which was derived from traditional breeding. This line, possessing a distinctive metabolite profile as a positive control, shows more differences vs. the parental than the transgenic line. Only succinic acid that falls outside the boundaries of natural variability between the two non-transgenic varieties C418 and C418/Xa23 should be further investigated with respect to safety or nutritional impact.

Capillary electrophoretic profiling of tryptic digests of water soluble proteins from Bacillus thuringiensis-transgenic and non-transgenic maize species.

Capillary zone electrophoresis (CZE) has been applied to separation and characterisation of enzymatic (tryptic) hydrolysates of water-soluble proteins from Bacillus thuringiensis (Bt)-transgenic (Aristis-Bt) and two native non-transgenic (Aristis and Coventry) maize varieties. Water-soluble proteins were extracted from the flour of these maize species and digested by bovine pancreatic trypsin immobilised on agarose gel in 100 mM ammonium hydrocarbonate buffer, pH 7.9. The yielded tryptic digests of proteins were analysed by CZE in four acidic background electrolytes (BGEs) (100 mM H₃PO₄, 50 mM Tris, pH 2.25; 500 mM acetic acid, pH 2.54; 200 mM formic acid, 200 mM acetic acid, pH 2.05; and 200 mM iminodiacetic acid, pH 2.26) using a lab-made CZE apparatus equipped with bare fused silica capillary and UV-absorption detector operating at 206 nm. Among the tested BGEs, the best resolution of the tryptic peptides of extracted proteins of the above three maize species was obtained in isoelectric BGE, 200 mM iminodiacetic acid, pH 2.26. Selected resolved tryptic peptides of proteins were characterised by effective electrophoretic mobilities and corrected (migration times normalised) peak areas. Some significant relative qualitative and quantitative differences in CZE-UV profiling of tryptic protein digests were found, which can be potentially used to differentiate transgenic Aristis Bt and non-transgenic Aristis varieties or two native non-transgenic varieties, Aristis and Coventry.

Effect of Pyramiding Bt and CpTI Genes on Resistance of Cotton to Helicoverpa armigera (Lepidoptera: Noctuidae) Under Laboratory and Field Conditions

Transgenic cotton (Cossypium hirsutum L.) varieties, adapted to China, have been bred that express two genes for resistance to insects, the CrylAc gene from Bacillus thuringiensis (Berliner) (Bt), and a trypsin inhibitor gene from cowpea (CpTI). Effectiveness of the double gene modification in conferring resistance to cotton bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae), was studied in laboratory and field experiments. In each experiment, performance of Bt+CpTI cotton was compared with Bt cotton and to a conventional nontransgenic variety. Larval survival was lower on both types of transgenic variety, compared with the conventional cotton. Survival of first-, second-, and third-stage larvae was lower on Bt+CpTI cotton than on Bt cotton. Plant structures differed in level of resistance, and these differences were similar on Bt and Bt + CpTI cotton. Likewise, seasonal trends in level of resistance in different plant structures were similar in Bt and Bt+CpTI cotton. Both types of transgenic cotton interfered with development of sixth-stage larvae to adults, and no offspring was produced by H. armigera that fed on Bt or Bt+CpTI cotton from the sixth stage onward. First-, second-, and third-stage larvae spent significantly less time feeding on transgenic cotton than on conventional cotton, and the reduction in feeding time was significantly greater on Bt+CpTI cotton than on Bt cotton. Food conversion efficiency was lower on transgenic varieties than on conventional cotton, but there was no significant difference between Bt and Bt+CpTI cotton. In 3-yr field experimentation, bollworm densities were greatly suppressed on transgenic as compared with conventional cotton, but no significant differences between Bt and Bt+CpTI cotton were found. Overall, the results from laboratory work indicate that introduction of the CpTI gene in Bt cotton raises some components of resistance in cotton against H. armigera, but enhanced control of H. armigera under field conditions, due to expression of the CpTI gene, was not demonstrated.

Effect of Bt genetic engineering on indirect defense in cotton via a tritrophic interaction

We present a tritrophic analysis of the potential non-intended pleiotropic effects of cry1Ac gene derived from Bacillus thurigiensis (Bt) insertion in cotton (DeltaPine 404 Bt Bollgard® variety) on the emission of herbivore induced volatile compounds and on the attraction of the egg parasitoid Trichogramma pretisoum (Hymenoptera: Trichogrammatidae). Both the herbivore damaged Bt variety and its non-Bt isoline (DeltaPine DP4049 variety) produced volatiles in higher quantity when compared to undamaged plants and significantly attracted the egg parasitoids (T. pretiosum) when compared to undamaged plants. However, Trichogramma pretiosum did not differentiate between the transgenic and nontransgenic varieties, suggesting that the ratios between the compounds released by herbivory damaged -Bt cotton and herbivory damaged-non Bt cotton did not change significantly. Finally, no detrimental effect of the Bt genetic engineering was detected related to the volatile compounds released by Bollgard cotton on the behavior of the natural enemy studied.