Editorial: Advances and Challenges of RNAi Based Technologies for Plants—Volume 2

Editorial on the Research Topic: Advances and Challenges of RNAi Based Technologies for Plants—Volume

Pollen-mediated intraspecific gene flow from herbicide resistant oilseed rape (Brassica napus L.)

Abstract The cultivation of genetically modified (GM) herbicide resistant oilseed rape (Brassica napus) has increased over the past few years. The transfer of herbicide resistance genes via pollen (gene flow) from GM crops to non-GM crops is of relevance for the realisation of co-existence of different agricultural cultivation forms as well as for weed management. Therefore the likelihood of pollen-mediated gene flow has been investigated in numerous studies. Despite the difficulty to compare different experiments with varying levels of outcrossing, we performed a literature search for worldwide studies on cross-fertilisation in fully fertile oilseed rape. The occurrence and frequency of pollenmediated intraspecific gene flow (outcrossing rate) can vary according to cultivar, experimental design, local topography and environmental conditions. The outcrossing rate from one field to another depends also on the size and arrangement of donor and recipient populations and on the ratio between donor and recipient plot size. The outcrossing levels specified in the presented studies are derived mostly from experiments where the recipient field is either surrounding the donor field (continuous design) or is located as a patch at different distances from the donor field (discontinuous design). Reports of gene flow in Brassica napus generally show that the amount of cross-fertilisation decreases as the distance from the pollen source increases. The evidence given in various studies reveals that the bulk of GM crossfertilisation occurs within the first 10 m of the recipient field. The removal of the first 10 m of a nontransgenic field facing a GM crop might therefore be more efficient for reducing the total level of crossfertilisation in a recipient sink population than to recommend separation distances. Future experiments should investigate cross-fertilisation with multiple adjacent donor fields at the landscape level under different spatial distributions of rapeseed cultivars and different cropping systems. The level of crossfertilisation occurring over the whole field is mainly important for co-existence and has not been investigated in agricultural scale experiments until now. Potential problems with herbicide resistant oilseed rape volunteers arising from intraspecific gene flow can be largely solved by the choice of suitable cultivars and herbicides as well as by soil management

Food and feed safety assessment of RNAi plants and products

This paper evaluates the potential hazards of food and feed derived from RNAi plants including: adverse changes of plant metabolism; mechanisms and potential for non-target gene silencing in humans and livestock, including gut microbiome; bioinformatics tools for predictionof off-target sequences of interfering RNA; the possible non-specific effects of dsRNA and siRNA in mammals; and the comparison of data requirements for safety assessment of food and feed from RNAi plants and from plants expressing recombinant proteins. It also discusses exposure and RNAi-specific risk assessment

Biological Confinement Strategies for Seed- and Pollen-Mediated Gene Flow of GM Canola ([i]Brassica napus[/i] L.)

International audienceCanola ([i]Brassica napus[/i]) varieties containing inherent restrictions on gene flow may address problems of seed- and pollen-mediated gene flow. The aim of this study was to explore the effectiveness of 1) low-dormancy varieties in avoiding GM soil seedbanks and volunteers, and 2) cleistogamous (clg) genotypes to avoid outcrossing.GM and non-GM varieties with altered seed ingredients had a wide dormancy range that turned out to be genetically determined. Quantitative trait locus (QTL) mapping identified four QTLs, which together explained 35% of the phenotypic variance. The fiber content of the seeds appeared to additionally affect seed dormancy. A qualitative polymerase chain reaction (PCR) assay was developed for clg canola by cloning and sequencing of clg1-specific DNA fragments. Detection of characteristic bands in 0.1% clg spiked samples illustrated the sensitivity of this method.The inherent traits of low dormancy and cleistogamy may be feasible tools to minimize gene flow and may be considered for coexistence of GM and non-GM canola

Correction to: RNAi, what is its position in crop protection? (Journal of Pest Science, (2020), 93, 4, (1125-1130), 10.1007/s10340-020-01238-2)

A correction to this paper has been published:https://doi.org/10.1007/s10340-021-01393-0

RNAi: What is its position in agriculture?

none12RNA interference (RNAi) is being developed and exploited to improve plants by modifying endogenous gene expression as well as to target pest and pathogen genes both within plants (i.e. host-induced gene silencing) and/or as topical applications (e.g. spray-induced gene silencing). RNAi is a natural mechanism which can be exploited to make a major contribution towards integrated pest management and sustainable agricultural strategies needed worldwide to secure current and future food production. RNAi plants are being assessed and regulated using existing regulatory frameworks for GMO. However, there is an urgent need to develop appropriate science-based risk assessment procedures for topical RNAi applications within existing plant protection products legislation.noneMezzetti B.; Smagghe G.; Arpaia S.; Christiaens O.; Dietz-Pfeilstetter A.; Jones H.; Kostov K.; Sabbadini S.; Opsahl-Sorteberg H.-G.; Ventura V.; Taning C.N.T.; Sweet J.Mezzetti, B.; Smagghe, G.; Arpaia, S.; Christiaens, O.; Dietz-Pfeilstetter, A.; Jones, H.; Kostov, K.; Sabbadini, S.; Opsahl-Sorteberg, H. -G.; Ventura, V.; Taning, C. N. T.; Sweet, J