GMOIT: a tool for effective screening of genetically modified crops.

BACKGROUND: Advancement in agricultural biotechnology has resulted in increasing numbers of commercial varieties of genetically modified (GM) crops worldwide. Though several databases on GM crops are available, these databases generally focus on collecting and providing information on transgenic crops rather than on screening strategies. To overcome this, we constructed a novel tool named, Genetically Modified Organisms Identification Tool (GMOIT), designed to integrate basic and genetic information on genetic modification events and detection methods. RESULTS: At present, data for each element from 118 independent genetic modification events in soybean, maize, canola, and rice were included in the database. Particularly, GMOIT allows users to customize assay ranges and thus obtain the corresponding optimized screening strategies using common elements or specific locations as the detection targets with high flexibility. Using the 118 genetic modification events currently included in GMOIT as the range and algorithm selection results, a "6 + 4" protocol (six exogenous elements and four endogenous reference genes as the detection targets) covering 108 events for the four crops was established. Plasmids pGMOIT-1 and pGMOIT-2 were constructed as positive controls or calibrators in qualitative and quantitative transgene detection. CONCLUSIONS: Our study provides a simple, practical tool for selecting, detecting, and screening strategies for a sustainable and efficient application of genetic modification.

Rational design and application of broad-spectrum antibodies for Bt Cry toxins determination.

Using the amino acid sequences and analysis of selected known structures of Bt Cry toxins, Cry1Ab, Cry1Ac, Cry1Ah, Cry1B, Cry1C and Cry1F we specifically designed immunogens. After antibodies selection, broad-spectrum polyclonal antibodies (pAbs) and monoclonal antibody (namely 1A0-mAb) were obtained from rabbit and mouse, respectively. The produced pAbs displayed broad spectrum activity by recognizing Cry1 toxin, Cry2Aa, Cry2Ab and Cry3Aa with half maximal inhibitory concentration (IC50) values of 0.12-9.86 µg/mL. Similarly, 1A0-mAb showed broad spectrum activity, recognizing all of the above Cry protein (IC50 values of 4.66-20.46 µg/mL) with the exception of Cry2Aa. Using optimizations studies, 1A10-mAb was used as a capture antibody and pAbs as detection antibody. Double antibody sandwich enzyme-linked immunosorbent assays (DAS-ELISAs) were established for Cry1 toxin, Cry2Ab and Cry3Aa with the limit of detection (LOD) values of 2.36-36.37 ng/mL, respectively. The present DAS-ELISAs had good accuracy and precisions for the determination of Cry toxin spiked tap water, corn, rice, soybeans and soil samples. In conclusion, the present study has successfully obtained broad-spectrum pAbs and mAb. Furthermore, the generated pAbs- and mAb-based DAS-ELISAs protocol can potentially be used for the broad-spectrum monitoring of eight common subtypes of Bt Cry toxins residues in food and environmental samples.

Plant characterization of insect-protected soybean.

Insect-protected soybean (SIP) that produces the Cry1A.105 and Cry2Ab2 insecticidal crystal proteins has been developed to provide protection from feeding damage caused by targeted lepidopteran insect pests. Typically, as part of environmental risk assessment (ERA), plant characterization is conducted, and the data submitted to regulatory agencies prior to commercialization of genetically modified (GM) crops. The objectives of this research were to: (a) compare soybean with and without the SIP trait in plant characterization field trials designed to fulfill requirements for submissions to global regulatory agencies and address China-specific considerations and (b) compare risk assessment conclusions across regions and the methodologies used in the field trials. The soybean with and without the SIP trait in temperate, tropical, and subtropical germplasm were planted in replicated multi-location trials in the USA (in 2012 and 2018) and Brazil (in 2013/2014 and 2017/2018). Agronomic, phenotypic, plant competitiveness, and survival characteristics were assessed for soybean entries with and without the SIP trait. Regardless of genetic background, growing region, season, or testing methodology, the risk assessment conclusions were the same: the evaluated insect-protected soybean did not differ from conventional soybean in evaluated agronomic, phenotypic, competitiveness, and survival characteristics indicating no change in plant pest/weed potential. These results reinforce the concept of data transportability across global regions, different seasons, germplasm, and methodologies that should be considered when assessing environmental risks of GM crops.

Prey-mediated effects of Mpp51Aa2-producing cotton on longevity and reproduction of Orius majusculus.

Genetically engineered (GE) cotton event MON 88702, producing Mpp51Aa2 (previously mCry51Aa2) from Bacillus thuringiensis (Bt), controls sucking pests, such as Lygus spp. (Hemiptera: Miridae) and thrips (Thysanoptera). Ingesting high doses of the insecticidal protein resulted in adverse effects on life table parameters of beneficial, predatory Orius spp. (Hemiptera: Anthocoridae). This triggered laboratory studies with more realistic food treatments, including different combinations of prey types with and without Bt protein to further characterize risks to this important group of non-target organisms. In this work, exclusive feeding of frozen spider mites (Tetranychus urticae, Acari: Tetranychidae) from Bt cotton confirmed adverse effects on longevity and fecundity of O. majusculus adults. Alternate feeding of Bt protein-containing spider mites and Bt-free Ephestia kuehniella (Lepidoptera: Pyralidae) eggs mitigated effects on longevity, but not on fecundity. When living larvae of Spodoptera littoralis (Lepidoptera: Noctuidae) from Bt cotton were fed to the predators, however, no effects on longevity and reproduction of female O. majusculus were observed, despite the fact that Bt protein concentrations in larvae were almost as high as concentrations in spider mites. When a diverse mix of prey species with various Bt protein concentrations is consumed in the field, it is unlikely that exposure of Orius spp. to Mpp51Aa2 is high enough to exert adverse effects on predator populations. MON 88702 cotton may thus be a valuable tool for integrated management of sucking pests.

Economic viability of releasing Bt cotton in Bangladesh: An early insight.

Insect resistant genetically modified Bt cotton (containing a gene of Bacillus thuringiensis) has substantial potentiality of mounting cotton productivity. This study unveils an early insight on the economic viability of Bt cotton in Bangladesh. A total of 248 traditional cotton farmers and 8 Bt cotton experimental fields were surveyed in April 2022 for achieving the objectives. The data were analysed using descriptive statistics. Findings showed that the cost of Bt cotton production was slightly higher than that of conventional cotton. However, Bt cotton yielded a productivity increase of 0.81 t/ha. The cultivation of Bt cotton resulted in a higher net return (USD 2436/ha) compared to conventional cotton (USD 1624/ha). The results further indicated that the use of insecticides and pesticides in Bt cotton was significantly lower compared to traditional cotton, thereby contributing to the preservation of the natural environment. Overall, cultivation of Bt cotton is economically viable and may generate environmental benefits. Steps are warranted to disseminate and expand its cultivation.

Bt Soybean Cry1Ac Does Not Affect Development, Reproduction, or Feeding Behavior of Red-Banded Stink Bug Piezodorus guildinii (Hemiptera: Pentatomidae).

Bt soybean cultivation is increasing worldwide. The Cry1Ac protein expressed in Bt soybean efficiently controls several lepidopteran pests. The stink bug, Piezodorus guildinii (Westwood), a major pest for soybean in the Americas, is not controlled by Bt crops, although possible sub-lethal effects may occur. Even if there were no negative effects for sting bug, ingesting toxins could affect its bio-controllers. We tested through ELISA detection if P. guildinii ingests Cry1Ac from Bt soybean and possible effects on its development, reproduction, survival, and feeding behavior. Biological traits were evaluated under controlled conditions of nymphs and adults feeding on pods of near-isogenic cultivars DM5958iPRO (Bt) and DM59i (non-Bt). Feeding behavior was recorded using an AC-DC electropenetrography (EPG) device. Results indicated that P. guildinii ingested the Cry1Ac protein; however, nymphal period and accumulated survival percentage did not differ between cultivars. Feeding on Bt soybean pods did not affect fecundity (i.e., number of egg masses and eggs/female) nor egg viability. Different feeding behaviors were only detected on the pathway phase (stylet penetration into plant tissue), which was more pronounced in the Bt cultivar. However, the total duration of the feeding activities on seeds was numerically higher (ca. 2X) on Bt plants compared to non-Bt. This is the first study to demonstrate that P. guildinii does ingest the Cry1Ac protein and excrete it without being absorbed, probably explaining the lack of direct adverse effects on its biological parameters. EPG could indicate that Bt soybean plants might be less palatable than non-Bt to red-banded stink bug.

A Thermostable Cas12b-Powered Bioassay Coupled with Loop-Mediated Isothermal Amplification in a Customized "One-Pot" Vessel for Visual, Rapid, Sensitive, and On-Site Detection of Genetically Modified Crops.

Genetically modified crops (GMCs) have been discussed due to unknown safety, and thus, it is imperative to develop an effective detection technology. CRISPR/Cas is deemed a burgeoning technology for nucleic acid detection. Herein, we developed a novel detection method for the first time, which combined thermostable Cas12b with loop-mediated isothermal amplification (LAMP), to detect genetically modified (GM) soybeans in a customized one-pot vessel. In our method, LAMP-specific primers were used to amplify the cauliflower mosaic virus 35S promoter (CaMV35S) of the GM soybean samples. The corresponding amplicons activated the trans-cleavage activity of Cas12b, which resulted in the change of fluorescence intensity. The proposed bioassay was capable of detecting synthetic plasmid DNA samples down to 10 copies/µL, and as few as 0.05% transgenic contents could be detected in less than 40 min. This work presented an original detection method for GMCs, which performed rapid, on-site, and deployable detection.

Glyphosate hormesis induced by treatment via seed stimulates the growth and biomass accumulation in soybean seedlings.

Glyphosate hormesis, identified as a potential means to enhance crop yields, encounters practical constraints because it is typically assessed through foliar applications. The expression and extend of hormesis in this approach are influenced by unpredictable environmental conditions, highlighting the need to explore alternative glyphosate application methods, such as seed treatment. This study aimed to assess glyphosate hormesis on growth rates and biomass accumulation in seedlings soybean cultivars. Two dose-response experiments [doses from 0 to 2880 g acid equivalent (ae) ha-1], one via foliar and one via seed, were conducted on three soybean cultivars [one non-glyphosate-resistant (NGR) and two glyphosate-resistant (GR, one RR and one RR2)]. In a subsequent experiment, three safe glyphosate doses (0, 90 and 180 g ae ha-1) applied via seed were evaluated on four soybean cultivars (two RR and two RR2). For foliar applications, the range of glyphosate doses increasing growth rates and dry biomass by 12-28 % were 5.6-45 g ae ha-1 for the NGR cultivar, of 45-720 g ae ha-1 for RR and of 11.25-180 g ae ha-1 for RR2. In the seed treatment, biomass increases of 16-60 % occurred at 45-180 g ae ha-1 for the NGR and RR cultivars, and 90-360 g ae ha-1 for RR2. Glyphosate doses of 90 and 180 g ae ha-1, applied via seeds, provided greater growth and biomass accumulation for the RR and RR2 soybean cultivars. Both foliar and seed applications of glyphosate increased growth and biomass accumulation in soybean cultivars, with seed treatments showing greater and more consistent enhancements. These findings propose practical and viable alternative for harnessing glyphosate hormesis to facilitate the early development of soybeans and potentially enhance crop yield.

Status quo of global bioindustry and its policy implications / 生物工程学报

The advent of the bioeconomy era is triggers a new wave of technology and industrial revolution. Bioeconomy has become the commanding heights that major developed countries and emerging economies try to seize. This paper analyzes the spatiotemporal characteristics of global bioindustry development from four perspectives: biomedical industry, genetically modified crop planting industry, bioenergy industry, and bio-based chemical industry. Then it summarizes the main characteristics of the development of the global bioindustry, and further put forward policy recommendations for the bottleneck problems in the development of China's bioindustry, which can guide the future development of China's bioeconomy.

Quality of silage produced from intercropped corn RR and soybeans RR / Qualidade de silagem produzida a partir de milho rr consorciado com soja RR

The objective of this study was to produce silage from intercropped RR glyphosate tolerant corn (RR - Roundup Ready) and RR soybeans under Brazilian Cerrado conditions. The research was carried out in off-season between February and June 2015, in Rio Verde, Goiás (Brazil). In the experimental period the rainfall was 865 mm and the average temperature of 23.7°C. Two trials were performed. The first had corn rows spaced in 1 m with a row of soybeans in the interrow. The second had double corn rows interspersed with one row of soybeans, all spaced in 0.50 m. In both trials, we used a randomized block design, in a 2x2+3 factorial scheme, with four replications. Primary factor consisted of two types of pre-sowing fertilization: one only in corn rows and the other over the total area. The secondary factor corresponded to two soybean varieties: medium and late cycle variety. In addition, three control treatments were made: one of corn and two of soybeans. The corn cutoff point was at the hard farinaceous stage when the milk line reaches half the grain, and in the sole crop soybean at the R5.5 final phase of grain filling. Silage was stored in PVC experimental silos for 60 days. The intercropped treatments, in both spatial arrangements, promoted increases in neutral detergent fiber and acid detergent fiber contents. Soybean monoculture presented high values of crude protein and ethereal extract. There were higher effluent losses in medium-cycle soybean variety silage when it was grown in single cropping. However, the lowest effluent losses were recorded for silages of medium-cycle soybean intercropped under a double row pre-sowing corn fertilization system. The soybeans mixed silages produced together with corn under off-season conditions did not yield satisfactory results.

Objetivou-se neste trabalho adequar o sistema de consórcio entre milho com tolerância ao herbicida glifosato (RR - Roundup Ready) e soja RR para obtenção de silagem de qualidade em condições do Cerrado brasileiro. A pesquisa foi conduzida na safrinha entre fevereiro e junho de 2015, em Rio Verde, Goiás (Brasil). A pluviosidade do período experimental foi de 865mm e a temperatura média de 23,7°C. Realizou-se dois ensaios, adequando formas de adubação de semeadura, arranjo de plantas e cultivares. Utilizou-se delineamento em blocos casualizados, em fatorial 2x2+3, com quatro repetições, sendo o fator primário duas modalidades de adubação de semeadura na linha: somente no milho, e em área total; o fator secundário correspondeu a duas variedades de soja: ciclo médio e tardio; mais três testemunhas: uma de milho e duas de soja. O ponto de corte do milho foi no estádio farináceo duro quando a linha do leite atinge metade do grão, e na soja em monocultivo no estádio fenológico R5.5, fase final de enchimento de grãos. Armazenou-se a silagem em silos experimentais de PVC por 60 dias. Os tratamentos de consórcio em ambos os arranjos aumentaram os teores de fibra em detergente neutro e fibra em detergente ácido. Os monocultivos de soja obtiveram valores elevados de proteína bruta e extrato etéreo. Ocorreu maior perda por efluente na silagem da variedade de soja de ciclo médio cultivada em monocultivo. No entanto, as menores perdas por efluente foram registradas para silagens de culturas de soja de ciclo médio consorciadas sob um sistema de fertilização pré-semeadura de linha de milho, no arranjo de linha dupla. A inserção de soja para produzir silagens mista juntamente com o milho em condições de safrinha não teve resultados satisfatórios.

Cultivos genéticamente modificados: las promesas y las buenas intenciones no bastan

Genetically modified crops: promises and good intentions are not enough (refutation to Espinoza et al. 2004, Rev. Biol. Trop. 52 (3): 727-732). The arguments presented by Espinoza et al. in their paper "Relationship of genetically modified crops with the environment and health of the Costa Rican human population" published in this journal (Rev. Biol. Trop. 52: 727-732, 2004) are questioned and refuted. The arguments are confronted with evidence offered by scientists and national and international independent organizations around the world (e.g. World Health Organization, Consumers international, Physicians and Scientists for Responsible Application of Science and Technology, international Union for Conservation of Nature and Natural Resources, the Council of the University of Costa Rica, and the independent Science Panel) showing the current uncertainty and limitations of science in this area, as well as those of proposed and applied biosafety approaches. Environment, biodiversity and food security are so important and basic matters, that there is need of serious testing, particularly when promises seem to be based on environmentally dangerous ideas promoted half a century ago by the so called "green revolution". Debate should continue, based on a holistic analysis of facts and with ethical reasoning, avoiding emotional positions that can confuse virtual reality with reality. Rev. Biol. Trop. 55 (2): 347-364. Epub 2007 June, 29.

Se refutan y cuestionan los razonamientos expuestos por las autoras en el artículo "Relación de los cultivos modificados genéticamente con el ambiente y la salud de la población costarricense" publicado en esta revista por Espinoza et al. (52: 727-732, 2004). Para ello se contraponen éstos con las evidencias expuestas y analizadas tanto por científicos como por organizaciones nacionales e internacionales independientes de diverso tipo en diferentes lugares del mundo (e.g. Organización Mundial de la Salud, internacional de Consumidores, Médicos y Científicos por una Aplicación Responsable de la Ciencia y la Tecnología, Unión internacional para la Conservación de la Naturaleza, Consejo Universitario de la Universidad de Costa Rica y el Panel de Ciencias independiente), que confirman la incertidumbre y limitaciones actuales de la ciencia en esta área, así como de los mecanismos de bioseguridad propuestos y puestos en vigor. En materias tan importantes y básicas para la supervivencia como las que nos ocupan -el ambiente, la biodiversidad y la seguridad alimentaria- no es prudente apostar a promesas basadas en la misma lógica promocionada desde hace poco más de cinco décadas por la denominada "revolución verde". Es necesario continuar este debate basado en el análisis holístico de los hechos, así como en razonamientos éticos, evitando caer en posiciones emocionales que llegan a confundir la realidad virtual con la verdadera realidad.