Genetic engineering at the heart of agroecology

We discuss whether genetic engineering and agroecology are compatible. For this, we investigated three cases of genetically engineered crops and considered agroecology as scientific discipline as well as a social movement. One case was the use of cisgenic modifications to make potato durably resistant to late blight, the second was the use of CRISPR/Cas to make rice resistant to bacterial blight and as a third case, we evaluated experiences with cultivating transgenic Bt crops. These cases demonstrated that genetic engineering offers opportunities to grow crops in novel integrated pest management (IPM) systems with, as direct benefit, a decrease in the use of chemical crop protection agents, and as indirect effect that the role of predators and biological control agents can become more important than in present conventional systems based on pesticides. We used a framework based on four concerns (both cons and pros) that were gathered from an extensive societal interaction organized around the Dutch research project DuRPh, which produced a proof-of-concept of a cisgenic late blight-resistant potato. We concluded that genetic engineering and agroecology certainly have synergy in the context of agroecology as science, when applied to making crops less vulnerable to pests and diseases and when combined with cultivation using IPM. By contrast, within the movement context, genetically engineered varieties may be welcomed if they include traits that contribute to successful IPM schemes and are socially benign. Whether they would actually be deemed desirable or acceptable will, however, vary depending on the norms and values of the social movements. We propose that some concerns may be reconcilable in a dialogue. Deontological arguments such as naturalness are more difficult to reconcile, as they relate to deeply felt ethical or cultural values. A step forward would be when also for these arguments everyone can make an informed choice and when these choices can coexist in a respectful manner.</p

The use of intellectual property systems in plant breeding for ensuring deployment of good agricultural practices

Breeding innovations are relevant for sustainable agricultural development and food security, as new, resilient production systems require crop varieties optimally suited for these systems. In the societal debate around genetic engineering and other plant breeding innovations, ownership of patents on the technology used in the hands of large companies is often seen as a reason that small breeding companies are denied opportunities for further improving varieties or that farmers are restricted in using such varieties. However, intellectual property (IP) systems may also be used as tools to ensure the use of good agricultural practices when cultivating the resulting varieties. This paper explores documented cases in which IP systems (plant variety rights, patents and brand names) are used to promote that innovative varieties are grown according to good agricultural practices (GAP). These include effective disease resistance management regimes in innovative crop varieties of potato in order to prevent or delay pathogens from overcoming disease resistance genes, management regimes for transgenic insect-resistant Bt or herbicide-tolerant crops to prevent the development of resistant pests or weeds, respectively. The results are discussed with respect to the influence of breeders on GAP measures through various forms of IP and the contribution and role of other stakeholders, authorities and society at large in stimulating and ensuring the use of GAP.</p

Genetic engineering at the heart of agroecology

We discuss whether genetic engineering and agroecology are compatible. For this, we investigated three cases of genetically engineered crops and considered agroecology as scientific discipline as well as a social movement. One case was the use of cisgenic modifications to make potato durably resistant to late blight, the second was the use of CRISPR/Cas to make rice resistant to bacterial blight and as a third case, we evaluated experiences with cultivating transgenic Bt crops. These cases demonstrated that genetic engineering offers opportunities to grow crops in novel integrated pest management (IPM) systems with, as direct benefit, a decrease in the use of chemical crop protection agents, and as indirect effect that the role of predators and biological control agents can become more important than in present conventional systems based on pesticides. We used a framework based on four concerns (both cons and pros) that were gathered from an extensive societal interaction organized around the Dutch research project DuRPh, which produced a proof-of-concept of a cisgenic late blight-resistant potato. We concluded that genetic engineering and agroecology certainly have synergy in the context of agroecology as science, when applied to making crops less vulnerable to pests and diseases and when combined with cultivation using IPM. By contrast, within the movement context, genetically engineered varieties may be welcomed if they include traits that contribute to successful IPM schemes and are socially benign. Whether they would actually be deemed desirable or acceptable will, however, vary depending on the norms and values of the social movements. We propose that some concerns may be reconcilable in a dialogue. Deontological arguments such as naturalness are more difficult to reconcile, as they relate to deeply felt ethical or cultural values. A step forward would be when also for these arguments everyone can make an informed choice and when these choices can coexist in a respectful manner.</p

No Tangible Effects of Field-Grown Cisgenic Potatoes on Soil Microbial Communities

DNA modification techniques are increasingly applied to improve the agronomic performance of crops worldwide. Before cultivation and marketing, the environmental risks of such modified varieties must be assessed. This includes an understanding of their effects on soil microorganisms and associated ecosystem services. This study analyzed the impact of a cisgenic modification of the potato variety Desirée to enhance resistance against the late blight-causing fungus Phytophthora infestans (Oomycetes) on the abundance and diversity of rhizosphere inhabiting microbial communities. Two experimental field sites in Ireland and the Netherlands were selected, and for 2 subsequent years, the cisgenic version of Desirée was compared in the presence and absence of fungicides to its non-engineered late blight-sensitive counterpart and a conventionally bred late blight-resistant variety. At the flowering stage, total DNA was extracted from the potato rhizosphere and subjected to PCR for quantifying and sequencing bacterial 16S rRNA genes, fungal internal transcribed spacer (ITS) sequences, and nir genes encoding for bacterial nitrite reductases. Both bacterial and fungal communities responded to field conditions, potato varieties, year of cultivation, and bacteria sporadically also to fungicide treatments. At the Dutch site, without annual replication, fungicides stimulated nirK abundance for all potatoes, but with significance only for cisgenic Desirée. In all other cases, neither the abundance nor the diversity of any microbial marker differed between both Desirée versions. Overall, the study demonstrates environmental variation but also similar patterns of soil microbial diversity in potato rhizospheres and indicates that the cisgenic modification had no tangible impact on soil microbial communities.</p

Development and validation of IPM strategies for the cultivation of cisgenically modified late blight resistant potato

Potato late blight disease remains the primary stressor of commercial potato production across the EU, typically requiring >10 fungicide applications per growing season to offset crop losses. In response, the goal of this study was to test and validate a novel, more durable, control strategy for potato late blight. This IPM2.0 strategy is based on the principles of Integrated Pest Management (IPM) which sees the deployment of a late blight resistant potato genotype, a cisgenically modified, Desiree based resistant potato line here, in conjunction with pathogen population monitoring for virulence to the resistance genes (R genes) deployed and a “do not spray unless”, low input fungicide spray strategy. Field evaluations were completed in the Netherlands and in Ireland in 2013, 2014 and in Ireland in 2015. Comparators used in this study included the original but susceptible potato variety Desiree and the conventional but highly resistant variety Sarpo Mira. The novel IPM2.0 strategy was compared to local common practice (fungicide applications on a near weekly basis) and an untreated control. Overall, the IPM2.0 control strategy validated here reduced the average fungicide input by 80–90% without compromising control efficacy. Corresponding environmental side-effects were reduced proportionally. The results underline the pragmatic role host resistance can provide to commercial potato production systems and to society at large if employed as part of an integrated late blight control system