-
1.
An Update on Genetic Modification of Chickpea for Increased Yield and Stress Tolerance.
Kumar, M, Yusuf, MA, Nigam, M, Kumar, M
Molecular biotechnology. 2018;(8):651-663
Abstract
Chickpea is a highly nutritious grain legume crop, widely appreciated as a health food, especially in the Indian subcontinent. The major constraints on chickpea production are biotic (Helicoverpa, bruchid, aphid, ascochyta) and abiotic (drought, heat, salt, cold) stresses, which reduce the yield by up to 90%. Various strategies like conventional breeding, molecular breeding, and modern plant breeding have been used to overcome these problems. Conventionally, breeding programs aim at development of varieties that combine maximum number of traits through inter-specific hybridization, wide hybridization, and hybridization involving more than two parents. Breeding is difficult in this crop because of its self-pollinating nature and limited genetic variation. Recent advances in in vitro culture and gene technologies offer unique opportunities to realize the full potential of chickpea production. However, as of date, no transgenic chickpea variety has been approved for cultivation in the world. In this review, we provide an update on the development of genetically modified chickpea plants, including those resistant to Helicoverpa armigera, Callosobruchus maculatus, Aphis craccivora, as well as to drought and salt stress. The genes utilized for development of resistance against pod borer, bruchid, aphid, drought, and salt tolerance, namely, Bt, alpha amylase inhibitor, ASAL, P5CSF129A, and P5CS, respectively, are discussed.
-
2.
Co-existence of GM, conventional and organic crops in developing countries: Main debates and concerns.
Azadi, H, Taube, F, Taheri, F
Critical reviews in food science and nutrition. 2018;(16):2677-2688
Abstract
The co-existence approach of GM crops with conventional agriculture and organic farming as a feasible agricultural farming system has recently been placed in the center of hot debates at the EU-level and become a source of anxiety in developing countries. The main promises of this approach is to ensure "food security" and "food safety" on the one hand, and to avoid the adventitious presence of GM crops in conventional and organic farming on the other, as well as to present concerns in many debates on implementing the approach in developing countries. Here, we discuss the main debates on ("what," "why," "who," "where," "which," and "how") applying this approach in developing countries and review the main considerations and tradeoffs in this regard. The paper concludes that a peaceful co-existence between GM, conventional, and organic farming is not easy but is still possible. The goal should be to implement rules that are well-established proportionately, efficiently and cost-effectively, using crop-case, farming system-based and should be biodiversity-focused ending up with "codes of good agricultural practice" for co-existence.
-
3.
Contribution of Untargeted Metabolomics for Future Assessment of Biotech Crops.
Christ, B, Pluskal, T, Aubry, S, Weng, JK
Trends in plant science. 2018;(12):1047-1056
Abstract
The nutritional value and safety of food crops are ultimately determined by their chemical composition. Recent developments in the field of metabolomics have made it possible to characterize the metabolic profile of crops in a comprehensive and high-throughput manner. Here, we propose that state-of-the-art untargeted metabolomics technology should be leveraged for safety assessment of new crop products. We suggest generally applicable experimental design principles that facilitate the efficient and rigorous identification of both intended and unintended metabolic alterations associated with a newly engineered trait. Our proposition could contribute to increased transparency of the safety assessment process for new biotech crops.
-
4.
[Molecular and genetic studies of genetically engineered potato: transformation event PH05-026-0048].
Tyshko, NV, Sadykova, EO, Sukhacheva, MV, Baturin, AK
Voprosy pitaniia. 2018;(4):25-31
Abstract
Expert evaluation of genetically engineered organisms (GMO) identification methods is aimed at confirmation their adequacy with the tool and methodological base used in the institutions of the Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing to control market turnover and labelling of genetically engineered food. The primer system's specificity was experimentally confirmed in studies with other GM potato lines, as well as with the results of the BLAST-analysis. The efficiency, linearity and correctness of the method meet the requirements of the European Union Reference Laboratory for GM Food and Feed. Limit of detection and limit of quantification of GM potato line PH05-026-0048 genomic DNA were 0.019% (11 copies of the GM potato genomic DNA) and 0.06% (36 copies of the GM genomic DNA of the potato) per 100 ng of total DNA, respectively.
-
5.
CRISPR/Cas9; A robust technology for producing genetically engineered plants.
Farooq, R, Hussain, K, Nazir, S, Javed, MR, Masood, N
Cellular and molecular biology (Noisy-le-Grand, France). 2018;(14):31-38
Abstract
CRISPR/Cas9 is a technology evolved from modified type II immune system of bacteria and archaea. Exploitation of this bacterial immune system in all eukaryotes including plants may lead to site-specific targeted genome engineering. Genome engineering is objectively utilized to express/silence a trait harbouring gene in the plant genome. In this review, different genetic engineering techniques including classical breeding, RNAi and genetic transformation and synthetic sequence-specific nucleases (zinc finger nucleases; ZFNs and transcription activator-like effector nuclease; TALENs) techniques have been described and compared with advanced genome editing technique CRISPR/Cas9, on the basis of their merits and drawbacks. This revolutionary genome engineering technology has edge over all other approaches because of its simplicity, stability, specificity of the target and multiple genes can be engineered at a time. CRISPR/Cas9 requires only Cas9 endonuclease and single guide RNA, which are directly delivered into plant cells via either vector-mediated stable transformation or transient delivery of ribonucleoproteins (RNPs) and generate double-strand breaks (DSBs) at target site. These DSBs are further repaired by cell endogenous repairing pathways via HDR or NHEJ. The major advantage of CRISPR/Cas9 system is that engineered plants are considered Non-GM; can be achieved using in vitro expressed RNPs transient delivery. Different variants of Cas9 genes cloned in different plasmid vectors can be used to achieve different objectives of genome editing including double-stranded DNA break, single-stranded break, activate/repress the gene expression. Fusion of Cas9 with fluorescent protein can lead to visualize the expression of the CRISPR/Cas9 system. The applications of this technology in plant genome editing to improve different plant traits are comprehensively described.
-
6.
Maximizing the expression of transgenic traits into elite alfalfa germplasm using a supertransgene configuration in heterozygous conditions.
Jozefkowicz, C, Frare, R, Fox, R, Odorizzi, A, Arolfo, V, Pagano, E, Basigalup, D, Ayub, N, Soto, G
TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik. 2018;(5):1111-1123
Abstract
A novel process for the production of transgenic alfalfa varieties. Numerous species of legumes, including alfalfa, are critical factors for agroecosystems due to their ability to grow without nitrogen fertilizers derived from non-renewable fossil fuels, their contribution of organic nitrogen to the soil, and their increased nutritional value. Alfalfa is the main source of vegetable proteins in meat and milk production systems worldwide. Despite the economic and ecological importance of this autotetraploid and allogamous forage crop, little progress has been made in the incorporation of transgenic traits into commercial alfalfa. This is mainly due to the unusually strong transgene silencing and complex reproductive behavior of alfalfa, which limit the production of events with high transgene expression and the introgression of selected events within heterogeneous synthetic populations, respectively. In this report, we describe a novel procedure, called supertransgene process, where a glufosinate-tolerant alfalfa variety was developed using a single event containing the BAR transgene associated with an inversion. This approach can be used to maximize the expression of transgenic traits into elite alfalfa germplasm and to reduce the cost of production of transgenic alfalfa cultivars, contributing to the public improvement of this legume forage and other polyploid and outcrossing crop species.
-
7.
Food safety evaluation for R-proteins introduced by biotechnology: A case study of VNT1 in late blight protected potatoes.
Habig, JW, Rowland, A, Pence, MG, Zhong, CX
Regulatory toxicology and pharmacology : RTP. 2018;:66-74
Abstract
Resistance genes (R-genes) from wild potato species confer protection against disease and can be introduced into cultivated potato varieties using breeding or biotechnology. The R-gene, Rpi-vnt1, which encodes the VNT1 protein, protects against late blight, caused by Phytophthora infestans. Heterologous expression and purification of active VNT1 in quantities sufficient for regulatory biosafety studies was problematic, making it impractical to generate hazard characterization data. As a case study for R-proteins, a weight-of-evidence, tiered approach was used to evaluate the safety of VNT1. The hazard potential of VNT1 was identified from relevant safety information including history of safe use, bioinformatics, mode of action, expression levels, and dietary intake. From the assessment it was concluded that Tier II hazard characterization was not needed. R-proteins homologous to VNT1 and identified in edible crops, have a history of safe consumption. VNT1 does not share sequence identity with known allergens. Expression levels of R-proteins are generally low, and VNT1 was not detected in potato varieties expressing the Rpi-vnt1 gene. With minimal hazard and negligible exposure, the risks associated with consumption of R-proteins in late blight protected potatoes are exceedingly low. R-proteins introduced into potatoes to confer late blight protection are safe for consumption.
-
8.
Boosting innate immunity to sustainably control diseases in crops.
Nicaise, V
Current opinion in virology. 2017;:112-119
Abstract
Viruses cause epidemics in all major crops, threatening global food security. The development of efficient and durable resistance able to withstand viral attacks represents a major challenge for agronomy, and relies greatly on the understanding of the molecular dialogue between viral pathogens and their hosts. Research over the last decades provided substantial advances in the field of plant-virus interactions. Remarkably, the advent of studies of plant innate immunity has recently offered new strategies exploitable in the field. This review summarizes the recent breakthroughs that define the mechanisms underlying antiviral innate immunity in plants, and emphasizes the importance of integrating that knowledge into crop improvement actions, particularly by exploiting the insights related to immune receptors.
-
9.
Molecular characterization of genetically-modified crops: Challenges and strategies.
Li, R, Quan, S, Yan, X, Biswas, S, Zhang, D, Shi, J
Biotechnology advances. 2017;(2):302-309
Abstract
Molecular characterization lays a foundation for safety assessment and subsequent monitoring of genetically modified (GM) crops. Due to the target-specific nature, conventional polymerase chain reaction (PCR)-based methods cannot comprehensively detect unintended gene insertions, let alone unknown GM events. As more and more new developed GM crops including new plant breeding technology (NPBT) generated crops are in the pipeline for commercialization, alternative -omics approaches, particularly next generation sequencing, have been developed for molecular characterization of authorized or unauthorized GM (UGM) crops. This review summarizes first those methods, addresses their challenges, and discusses possible strategies for molecular characterization of engineered crops generated by NPBT, highlighting needs for a global information-sharing database and cost-effective, accurate and comprehensive molecular characterization approaches.
-
10.
Characterization of scientific studies usually cited as evidence of adverse effects of GM food/feed.
Sánchez, MA, Parrott, WA
Plant biotechnology journal. 2017;(10):1227-1234
Abstract
GM crops are the most studied crops in history. Approximately 5% of the safety studies on them show adverse effects that are a cause for concern and tend to be featured in media reports. Although these reports are based on just a handful of GM events, they are used to cast doubt on all GM crops. Furthermore, they tend to come from just a few laboratories and are published in less important journals. Importantly, a close examination of these reports invariably shows methodological flaws that invalidate any conclusions of adverse effects. Twenty years after commercial cultivation of GM crops began, a bona fide report of an adverse health effect due to a commercialized modification in a crop has yet to be reported.