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To respect the European labelling threshold for the adventitious presence of genetically modified organisms (GMOs) in food
and feed, stakeholders mainly rely on real-time PCR analysis, which provides a measurement expressed as a percentage of GM-DNA.
However, this measurement veils the complexity of gene flow, especially in the case of gene stacking. We have investigated
the impact of gene stacking on adventitious GM presence due to pollen flow and seed admixture as well as its translation in
terms of the percentage of GM-DNA in a non-GM maize harvest. In the case of varieties bearing one to four stacked events,
we established a set of relationships between the percentage of GM kernels and the percentage of GM-DNA in a non-GM harvest
as well as a set of relationships between the rate of seed admixture and the percentages of GM material in a non-GM harvest.
Thanks to these relationships, and based on simulations with a gene flow model, we have been able to demonstrate that the
number of events and the stacking structure of the emitting fields impact the ability of a non-GM maize producer to comply
with given GM kernel or GM-DNA thresholds. We also show that a great variability in the rates of GM kernels, embryos and DNA
results from seed admixture. Finally, the choice of a unit of measurement for a GM threshold in seed lots can have opposite
effects on the ability of farmers to comply with a given threshold depending on whether they are crop or seed producers. 相似文献
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Isabelle Fock Cécile Collonnier Danielle Lavergne Sébastien Vaniet Annick Ambroise Jacques Luisetti Hippolyte Kodja Darasinh Sihachakr 《Plant Physiology and Biochemistry》2007,45(3-4):209-215
Somatic hybrids of potato with a cultivated relative, Solanum stenotomum also called Solanum tuberosum Stenotomum group, were evaluated for their physiological and agronomical characteristics as well as the stability of the introgressed resistance to bacterial wilt, caused by Ralstonia solanacearum, after a long-term in vitro conservation for more than 5 years. Analysis of photosynthesis showed that the PEPC/Rubisco ratio remained lower than 0.5 for all vitroplants of potato and the somatic hybrids, except for the relative species. This indicates that the carbon metabolism is heterotrophic (ratio>1) for S. stenotomum, and autotrophic for potato and the somatic hybrids (ratio<1). In both in vitro and greenhouse conditions, potato and the somatic hybrids produced few bigger tubers, while many small tubers were obtained from the relative. The hybrid tubers were morphologically intermediate. The starch content of hybrid tubers was much lower than that of potato, but similar to that of the relative species. Interestingly, the level of bacterial resistance, introgressed from S. stenotomum into potato, was shown to be very stable and remained as high as that of the relative after a long-term period of in vitro conservation. 相似文献
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CRISPR‐Cas9‐mediated efficient directed mutagenesis and RAD51‐dependent and RAD51‐independent gene targeting in the moss Physcomitrella patens 下载免费PDF全文
Cécile Collonnier Aline Epert Kostlend Mara François Maclot Anouchka Guyon‐Debast Florence Charlot Charles White Didier G. Schaefer Fabien Nogué 《Plant biotechnology journal》2017,15(1):122-131
The ability to address the CRISPR‐Cas9 nuclease complex to any target DNA using customizable single‐guide RNAs has now permitted genome engineering in many species. Here, we report its first successful use in a nonvascular plant, the moss Physcomitrella patens. Single‐guide RNAs (sgRNAs) were designed to target an endogenous reporter gene, PpAPT, whose inactivation confers resistance to 2‐fluoroadenine. Transformation of moss protoplasts with these sgRNAs and the Cas9 coding sequence from Streptococcus pyogenes triggered mutagenesis at the PpAPT target in about 2% of the regenerated plants. Mainly, deletions were observed, most of them resulting from alternative end‐joining (alt‐EJ)‐driven repair. We further demonstrate that, in the presence of a donor DNA sharing sequence homology with the PpAPT gene, most transgene integration events occur by homology‐driven repair (HDR) at the target locus but also that Cas9‐induced double‐strand breaks are repaired with almost equal frequencies by mutagenic illegitimate recombination. Finally, we establish that a significant fraction of HDR‐mediated gene targeting events (30%) is still possible in the absence of PpRAD51 protein, indicating that CRISPR‐induced HDR is only partially mediated by the classical homologous recombination pathway. 相似文献
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F. Rizza G. Mennella C. Collonnier D. Sihachakr V. Kashyap M. Rajam M. Presterà G. Rotino 《Plant cell reports》2002,20(11):1022-1032
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Applications of biotechnology in eggplant 总被引:10,自引:0,他引:10
Collonnier C. Fock I. Kashyap V. Rotino G.L. Daunay M.C. Lian Y. Mariska I.K. Rajam M.V. Servaes A. Ducreux G. Sihachakr D. 《Plant Cell, Tissue and Organ Culture》2001,65(2):91-107
Eggplant (Solanum melongena L.), an economically important vegetable crop in many countries in Asia and Africa, often has insufficient levels of resistance
to biotic and abiotic stresses. Genetic resources of eggplant have been assessed for resistance against its most serious diseases
and pests (bacterial and fungal wilts, nematodes and shoot and fruit borer). Attempts at crossing eggplant with its wild relatives
resulted in limited success due to sexual incompatibilities. However, the ability of eggplant to respond well in tissue culture,
notably plant regeneration, has allowed the application of biotechnology, particularly the exploitation of somaclonal variation,
haploidisation, somatic hybridisation and genetic transformation for gene transfer. Somaclonal variation has been used to
obtain lines with increased resistance to salt and little leaf disease. Traits of resistance against bacterial and fungal
wilts have successfully been introduced into the cultivated eggplant through somatic hybridisation. However, most somatic
hybrids were sterile when the parental lines were distantly related. In contrast, the use of close relatives as fusion partners
or highly asymmetric fusion resulted in the production of fertile hybrids with resistance traits and a morphology close to
the cultivated eggplant, thus avoiding the series of backcrosses necessary for introgression of desired traits into eggplant.
As far as molecular markers and genetic engineering are concerned, the information available for eggplant is very scanty.
Two genetic linkage maps have been established by using RAPD and RFLP markers. In order to analyse the genetic relationships
between eggplant and its relatives, some studies based on AFLP and ctDNA analyses have also been conducted. So far only resistance
against insects, and parthenocarpic fruit development have successfully been developed in eggplant using Agrobacterium tumefasciens transformation. However, some work on genetic engineering of eggplant for other biotic and abiotic stresses has recently
been initiated.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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Paul Arens Carmen Mansilla Daniël Deinum Laetitia Cavellini André Moretti Sophie Rolland Hanneke van der Schoot David Calvache Fernando Ponz Cécile Collonnier René Mathis Diederik Smilde Carole Caranta Ben Vosman 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,120(3):655-664
Molecular markers linked to phenotypically important traits are of great interest especially when traits are difficult and/or costly to be observed. In tomato where a strong focus on resistance breeding has led to the introgression of several resistance genes, resistance traits have become important characteristics in distinctness, uniformity and stability (DUS) testing for Plant Breeders Rights (PBR) applications. Evaluation of disease traits in biological assays is not always straightforward because assays are often influenced by environmental factors, and difficulties in scoring exist. In this study, we describe the development and/or evaluation of molecular marker assays for the Verticillium genes Ve1 and Ve2, the tomato mosaic virus Tm1 (linked marker), the tomato mosaic virus Tm2 and Tm2 2 genes, the Meloidogyne incognita Mi1-2 gene, the Fusarium I (linked marker) and I2 loci, which are obligatory traits in PBR testing. The marker assays were evaluated for their robustness in a ring test and then evaluated in a set of varieties. Although in general, results between biological assays and marker assays gave highly correlated results, marker assays showed an advantage over biological tests in that the results were clearer, i.e., homozygote/heterozygote presence of the resistance gene can be detected and heterogeneity in seed lots can be identified readily. Within the UPOV framework for granting of PBR, the markers have the potential to fulfil the requirements needed for implementation in DUS testing of candidate varieties and could complement or may be an alternative to the pathogenesis tests that are carried out at present. 相似文献
7.
Fabien Nogué Kostlend Mara Cécile Collonnier Josep M. Casacuberta 《Plant cell reports》2016,35(7):1475-1486
Key message
New tools for the precise modification of crops genes are now available for the engineering of new ideotypes. A future challenge in this emerging field of genome engineering is to develop efficient methods for allele mining.Abstract
Genome engineering tools are now available in plants, including major crops, to modify in a predictable manner a given gene. These new techniques have a tremendous potential for a spectacular acceleration of the plant breeding process. Here, we discuss how genetic diversity has always been the raw material for breeders and how they have always taken advantage of the best available science to use, and when possible, increase, this genetic diversity. We will present why the advent of these new techniques gives to the breeders extremely powerful tools for crop breeding, but also why this will require the breeders and researchers to characterize the genes underlying this genetic diversity more precisely. Tackling these challenges should permit the engineering of optimized alleles assortments in an unprecedented and controlled way.
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