Are innovative cropping systems less dependent on synthetic pesticides to treat Septoria leaf blotch (Zymoseptoria tritici) than conventional systems?
Introduction
Throughout the last few decades, conventional agriculture has characteristically relied on sizeable synthetic pesticide inputs to mitigate crop pest and pathogen damages (Foley et al., 2005). Despite clear benefits (Cooper and Dobson, 2007), the use of synthetic pesticides has come under increasing criticism due to their negative effects on the natural environment – especially biodiversity loss (Geiger et al., 2010; Outhwaite et al., 2022) and air-water pollution (Arias-Estévez et al., 2008; Silva et al., 2019) – and on human health (Budzinski and Couderchet, 2018). Research has shown that synthetic pesticides provide only short-term protection as, in the long term, evolutionary processes make pests and pathogens tolerant toward pesticide toxicity and thus lead to an increase in their dosage and economic cost (Hawkins et al., 2019; Pimentel, 2005). This is compounded by a downturn in new synthetic molecule development in favour of other, more sustainable molecules (Umetsu and Shirai, 2020). These challenges now call for alternative pest management strategies (Barzman and Dachbrodt-Saaydeh, 2011; Lamichhane et al., 2016; Lee et al., 2019). Alternative methods against pests and pathogens, both preventive and curative, have been provided by environmental policies such as the European Parliament and the EU Council's Directive 2009/128/EC (European Parliament, 2009). One suggested solution involves the adoption of innovative cropping systems, which affect the life cycle of pests and pathogens while reducing synthetic pesticide inputs (Jacquet et al., 2022; Lamichhane, 2017; Meynard et al., 2003).
To reduce reliance on synthetic pesticides, innovative cropping systems use mechanisms based on the meticulous design, integration, and management of an array of agricultural practices, such as sowing date, intercropping, N fertilization, sowing plant density, use of genetically resistant crop varieties and soil management (Loyce et al., 2008). Each practice achieves partial control of a targeted pest or pathogen, and their interactions constitute the cropping system's overall agroecological pest management strategy (Belmain et al., 2022). Following the eight principles of IPM (Barzman et al., 2015), instead of disentangling the singular pest control effect of each agricultural practice, this systemic approach evaluates the cropping system for its pest control efficacy as a whole (Drinkwater, 2002; Loyce et al., 2012; Lechenet et al., 2017). For example, Loyce et al. (2008) showed the potential to control fungal winter wheat diseases by means of a technique combining the management of seed sowing density and sowing date, with the use of genetically resistant varieties. By inhibiting fungal spore development and spread, this combination allows for a reduction in synthetic pesticide inputs. Moreover, Chikowo et al. (2009) have shown how to perform efficient weed management on winter cereals and summer crops by adjusting crop rotation, soil tillage and mechanical weeding, thereby reducing the necessity for chemical protection inputs. In order to increase crop tolerance against pest and pathogen damage, it is essential that agricultural practices be combined coherently (Debaeke et al., 2009; Rempelos et al., 2018), to minimize potential yield losses caused by the lack of chemical protections (Hossard et al., 2014).
Septoria leaf blotch, a foliar disease caused by the pathogenic fungus Zymoseptoria tritici (Roberge ex Desm.) Quaedvl. & Crous., is widespread in winter wheat (Triticum aestivum L.) and is responsible for severe yearly yield losses (McDonald and Mundt, 2016; O'Driscoll et al., 2014). The intensive agricultural practices commonly adopted in conventional cropping systems have been proved to foster the onset, development, spread, and severity of Septoria in winter wheat, thus requiring iterative synthetic pesticide inputs (Fones and Gurr, 2015; Loyce et al., 2008). For instance, an earlier sowing date can increase the likelihood of a Septoria infestation due to the prolonged exposure of seedlings to the previous year's debris, which are known to be a reservoir for fungal spores (Morais et al., 2016; Suffert et al., 2011). Higher sowing density can result in a closer canopy, which helps spores spread between neighbouring plants through splash dispersion or leaf-to-leaf contact (Lovell et al., 2004; Morais et al., 2015). A closer canopy can create a microenvironment with higher humidity in the lower layers of the crop vegetation favouring fungus development (Tompkins et al., 1993). Intensive monocultures based on a single winter wheat variety are more prone to severe Septoria (Kristoffersen et al., 2020) and can facilitate the pathogenic fungus' ability to overcome the wheat's genetic resistances (Mahboubi et al., 2022; Makhdoomi et al., 2015). Research has suggested that redesigning and coherently combining these agricultural practices within innovative cropping systems to curtail the viability of Septoria should lead to a partial or total cut in synthetic pesticide inputs (Jørgensen et al., 2014).
Previous research has already compared Septoria leaf blotch severity between innovative winter wheat cropping systems with different synthetic pesticide input regimes (Loyce et al., 2008; Rempelos et al., 2020). What remains to be quantified, however, is innovative cropping systems’ reliance on synthetic pesticides and the extent to which the design of agricultural practices can mitigate the effects of partial or complete synthetic pesticide cuts on Septoria severity. In addition, the long-term effects of lower synthetic pesticide inputs on both crop damage and harvested yield remain unknown. In this article, we set out to: (1) compare Septoria severity and harvested yield between one conventional and three innovative winter wheat cropping systems when treated and not treated with synthetic pesticides during five consecutive growing seasons; (2) identify which innovative cropping system performs best in reducing disease severity during years with higher disease pressure through the use of well-designed agricultural practices; (3) verify if harvested yields is influenced by reductions in synthetic pesticide inputs. Results should provide farmers with information to foster the ongoing trend towards switching from conventional practices towards a sustainable agriculture for the future.
Section snippets
Description of the study site “La Cage”
The study was conducted at the experimental site “La Cage” (Fig. 1), which was established in 1998 by INRAE (Institut national de recherche pour l'agriculture, l'alimentation et l'environment) located 15 km southwest of Paris (48°48′ N, 2°08′ E), France. According to the FAO classification, the experimental site's soil is a deep Luvisol, with a 58% silt, 25% sand and 17% clay average. This soil has a neutral pH and the climate at this site is temperate, with 640 mm mean annual precipitation and
Results
The four cropping systems showed inter-annual variability in Septoria severity, with higher percentages in 2014 and 2016 which were exacerbated by the absence of pesticide treatments (Table 2). The highest degree of severity was recorded in 2014 in the conventional system's NP zone while the lowest degree of severity was measured in 2015, when <5% of Septoria severity were recorded in all cropping systems, specifically in the PT zone of the conventional, low-input and conservation agriculture
Discussion
The prevalent use of synthetic pesticides in agriculture has caused severe detrimental effects on natural environments (Outhwaite et al., 2022). Our study aimed to support a more sustainable pest management strategy, through the design of innovative cropping systems which can mitigate reliance on synthetic pesticides while minimizing yield losses. Besides the relatively low number of replicates, we found that low-input, conservation agriculture and organic systems were able to mitigate the
Conclusion
Overall, this study provides long-term evidence of the ability of two innovative cropping systems, low-input and conservation agriculture, to minimize synthetic pesticide inputs and, to a large extent, control disease pressure in consecutive growing seasons. Conservation agriculture was characterized by a high disease control capacity but failed to translate this into high yield production. In contrast, low-input showed a production similar to the conventional system and a lower susceptibility
Funding sources
This study was funded by Consortium Biocontrôle in the framework of the IBC – Intégration du Biocontrôle – project.
CRediT authorship contribution statement
Bellone Davide: Conceptualization, Investigation, Analysis, Visualization, Writing-original draft; Corentin Barbu and Arnaud Gauffreteau: Investigation, Analysis, Editing; Marie-Hélène Jeuffroy, Michel Bertrand, Muriel Morison-Valantin: Conceptualization, Investigation and Editing; Marie Noel Mistou: Data Curation, Investigation; Elsa Ballini: Editing; Foteini G. Pashalidou: Funding acquisition, Conceptualization, Investigation, Analysis, Editing.
Declaration of competing interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
References (70)
- et al.
The mobility and degradation of pesticides in soils and the pollution of groundwater resources
Agric. Ecosyst. Environ.
(2008) - et al.
Unfolding the potential of wheat cultivar mixtures: a meta-analysis perspective and identification of knowledge gaps
Field Crop. Res.
(2018) - et al.
Influence of cropping system factors on pesticide use intensity - a multivariate analysis of on-farm data in North East Germany
Eur. J. Agron.
(2012) - et al.
Integrated Weed Management systems allow reduced reliance on herbicides and long-term weed control
Agric. Ecosyst. Environ.
(2009) - et al.
The benefits of pesticides to mankind and the environment
Crop Protect.
(2007) - et al.
The crop yield gap between organic and conventional agriculture
Agric. Syst.
(2012) - et al.
The impact of Septoria tritici Blotch disease on wheat: an EU perspective
Fungal Genet. Biol.
(2015) - et al.
Persistent negative effects of pesticides on biodiversity and biological control potential on European farmland
Basic Appl. Ecol.
(2010) - et al.
IPM strategies and their dilemmas including an introduction to
J. Integr. Agric.
(2014) - et al.
Control of Septoria tritici blotch by winter wheat cultivar mixtures: meta-analysis of 19 years of cultivar trials
Field Crop. Res.
(2020)
Adoption of conservation agriculture in Europe. Lessons of the KASSA project
Land Use Pol.
Pesticide use and risk reduction in European farming systems with IPM: an introduction to the special issue
Crop Protect.
Identification of two endophytic fungi that control Septoria tritici blotch in the field, using a structured screening approach
Biol. Control
Succession of the fungal endophytic microbiome of wheat is dependent on tissue-specific interactions between host genotype and environment
Sci. Total Environ.
Diversity of methodologies to experiment Integrated Pest Management in arable cropping systems: analysis and reflections based on a European network
Eur. J. Agron.
Assessment of policy instruments for pesticide use reduction in Europe; Learning from a systematic literature review
Crop Protect.
Growing winter wheat cultivars under different management intensities in France: a multicriteria assessment based on economic, energetic and environmental indicators
Field Crop. Res.
Interaction between cultivar and crop management effects on winter wheat diseases, lodging, and yield
Crop Protect.
Agronomic approach: cropping systems and plant diseases
Comptes Rendus Biol.
The wheat-Septoria conflict: a new front opening up?
Trends Plant Sci.
Pesticide residues in European agricultural soils – a hidden reality unfolded
Sci. Total Environ.
Earthworms promote the reduction of Fusarium biomass and deoxynivalenol content in wheat straw under field conditions
Soil Biol. Biochem.
Nutritional quality and health risks of wheat grains from organic and conventional cropping systems
Food Chem.
Effect of agronomic practices on the development of Septoria leaf blotch and its subsequent effect on growth and yield components of wheat
Pakistan J. Bot.
Studies on dispersal of Septoria tritici pycnidiospores in wheat-clover intercrops
Plant Pathol.
Eight principles of integrated pest management
Agron. Sustain. Dev.
Comparative analysis of pesticide action plans in five European countries
Pest Manag. Sci.
Fitting linear mixed-effects models using lme4
J. Stat. Software
How agricultural techniques mediating bottom - up and top - down regulation foster crop protection against pests
A review. Agron. Sustain. Dev.
Elements of agroecological pest and disease management
Elementa: Science of the Anthropocene
Improved control of septoria tritici blotch in durum wheat using cultivar mixtures
Plant Pathol.
Diseases in intercropping systems
Annu. Rev. Phytopathol.
Environmental and human health issues related to pesticides: from usage and environmental fate to impact
Environ. Sci. Pollut. Res.
Designing innovative productive cropping systems with quantified and ambitious environmental goals
Renew. Agric. Food Syst.
Beta regression in R
J. Stat. Software
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