Innovative formulations by encapsulation of entomopathogenic nematodes for use against codling moth, Cydia pomonella – CapCydia

Conventional plant protection products remain the main means of controlling insect pests. The negative impact of these substances on the environment and human health is significant. More environmentally friendly solutions exist but remain not sufficiently implemented due to technological barriers hindering their widespread operational use. In fact, main biocontrol solutions are based on active substances that are vulnerable to external agents, such as UV radiation, making them somewhat fragile in the field. Encapsulating natural active ingredients in shells addresses this issue by protecting them and optimizing their use in the field.

Within the framework of the CapCydia project, we propose to develop a biological-based solution for controlling codling moth, Cydia pomonella, using entomopathogenic nematodes (EPNs), insect parasites naturally occurring in the soil. These EPNs have been known for a long time but their use for biological crop protection remains limited to a few niche markets, primarily due to their fragility in the field. Previous works have demonstrated our ability to protect, in a capsule made of a biodegradable polymer of natural origin, different species of EPNs in association with natural active ingredients, thus increasing their resistance and stability in environmental conditions. In the CapCydia project, our goal will be to develop "Attract-and-Kill" systems consisting of complex formulations combining EPNs strains with attracting and stabilizing molecules. These combinations will be evaluated in the laboratory with different strains of EPNs, including indigenous strains isolated from orchards, and then we will demonstrate their effectiveness in the field through in situ pilot-scale trials.

The codling moth possess strong evolutionary capabilities allowing it to develop resistance to the various chemical or bio-control molecules available on the market. This pest represents a significant agronomic challenge, being responsible for 30 to 40% of insecticide treatments on apple trees across France. Developing production strategies that reduce the use of pesticides is a major challenge in agriculture. The main current methods used in organic agriculture rely on the use of mating disruption associated with viral preparations, for which resistance have been observed. In regions with high pressure, such as the Southeast basin, this protection strategy is insufficient to cover the entire C. pomonella lifecycle. Another means of protection is the use of plastic exclusion nets but this raises questions of environmental and landscape impact. Other approaches need to be activated in order to diversify and strengthen control measure.

The CapCydia project is part of an integrated pest management approach, proposing a new tool based on innovative formulations of EPNs to diversify bio-control and limit resistance emergence. First users concerned will be fruit growers.

This project is based on a strong research and innovation partnership established for several years. The consortium includes three academic partners (i) IEM will contribute its expertise in the formulation of biocontrol active ingredients, (ii) DGIMI and PSH units will be responsible for evaluating nematode formulations in the laboratory, (iii) technical centers CTIFL and SudExpé will collaborate for field studies. Finally, the SATT AxlR, as the technology’s valorization agent, will support the project’s technical development to facilitate the market launch of the developed product.