GM Potato Environmental Trial Results Published
Teagasc have concluded their field study which investigated both the environmental and agronomic impact of a GM potato variety genetically engineered to resist late blight disease, caused by Phytophthora infestans. Potato late blight can rapidly destroy potato crops with growers commonly having to resort to spraying their crops with fungicides on a near weekly basis.
Teagasc research indicates that combining a cisgenic blight resistant potato with advanced Integrated management systems can reduce the environmental impact of potato production by over 95%.
As part of the EU funded ‘AMIGA’ project and in collaboration with Wageningen University, Teagasc looked at issues such as the efficacy of disease control and the resulting environmental impact during cultivation of a susceptible potato variety (Désirée) and two different resistant potato varieties: Sarpo Mira, developed through conventional breeding, and a resistant version of the Désirée which received a resistance gene from a wild potato through cisgenesis. Cisgenesis allows enrichment of existing potato varieties in as little as 3 years versus current potato breeding programmes that require 12 years or more to produce a novel variety.
After undergoing independent peer-review, the findings from 3 years of field evaluations have been published in the scientific journals European Journal of Agronomy and BMC Ecology.
The research, conducted in both The Netherlands and Ireland, has concluded that integrated production strategies that include varieties with enhanced genetic resistance against late blight disease can reduce the average fungicide input by 80-90%, without compromising control efficacy or yield. This can provide more durable control options for farmers while significantly reducing the crop’s environmental footprint.
The international team developed an ‘IPM2.0’ approach which includes late blight resistant varieties and builds on the preventive principles of Integrated Pest Management. IPM2.0 could permit growers to strongly reduce the necessary input of chemical control agents. It also ensures a yield equivalent to current practise, protects the limited natural germplasm used to create the resistant varieties and significantly reduces the environmental impact of potato cultivation as a whole.
The IPM2.0 approach adds three extra components to the current control strategy for potato late blight: the use of resistant varieties, active monitoring of the late blight pathogen and a ‘do not spray unless’ strategy, which dictates that a grower only needs to apply fungicides when a resistant variety is at risk of infection due to pathogen adaptation. This strategy ensures potato crops are protected at all times while minimising the risk that resistance genes lose their efficacy.
The internationally recognised and publicly available Environmental Yardstick for Pesticides was used to quantify environmental impact. Based on this the late blight susceptible variety Désirée cultivated under common practice received more than 700 environmental impact points. The same variety cultivated under IPM2.0 reduced this score to circa 400 points. Both resistant varieties however scored much better under IPM2.0: cultivation of Sarpo Mira received an annual average of only 40 points, while the cisgenic resistant version of Désirée scored less than ten points.
Additional environmental investigations examined populations of soil nematodes, which play a key role in soil processes with alterations in the nematode community structure having the potential to considerably influence ecosystem functioning. In effect, fluctuations in nematode diversity and/or community structure can be gauged as a ‘barometer’ of a soil’s functional biodiversity.
Based on the metrics studied, the cultivation of the cisgenic potato variety had no significant effect on nematode community diversity or structure, compared to the non-engineered control variety. In contrast, significant differences were identified between each year of the study due to fluctuating climates and also between the varieties studied due to different plant structures.
In parallel to the active research programme, project staff completed over 95 knowledge transfer events across the country in support of the public discussion on the challenges facing future potato production and the costs/benefits of potential solutions.
For more information see European Journal of Agronomy 96 (2018) 146 – 155 and BMC Ecology (2016), 16:55 DOI 10.1186/s12898-016-0109-5
For more information on the Environmental Yardstick to determine the environmental impact, see https://www.milieumeetlat.nl/en/home.html