Impact of Climate Change and Adaptation Measures on Present and Potential Future Field Crop Pests in Quebec

Climate change will have impacts on Quebec’s agricultural production. The increase in average temperatures and the accumulation of degree days will be favourable to the development of some crops, yet will also promote existing pests and invasive alien species (IAS).

Field crops (corn, soybeans, wheat, canola) cover more than one million hectares of land in Quebec and constitute an important contribution to the economy. It is therefore essential to assess the potential phytosanitary problems of these crops in connection with the anticipated changing climate.

• Identify the main species of insects and major crop diseases that will be affected by climate change among those that are already present in Quebec or that could possibly have the capacity to establish themselves;

• Assess the impacts of climate change on the distribution area, the phenological development or capacity to establish of targeted species, and on damage to crops;

• Identify possible adaptation measures for the targeted species and more generally for the protection of field crops.

• Literature review on insect species and diseases that pose a risk to field crops in connection with the anticipated climate change;

• Selection of five species among those identified in the previous step following a consultation of experts in crop protection;

• Development and use of bioclimatic models to assess the impacts of climate change on the distribution area, phenological development, establishment capacity of target species, and damage to crops for the 2041–2070 horizon;

• Analysis of the situation for the target species in regions of the world currently subject to a climate similar to the one projected for Quebec for the 2041–2070 horizon in order to validate certain impacts and identify adaptation measures.

The project identified 230 insect pests and 267 diseases, including 26 nematodes, affecting field crops (soybean, corn, wheat, barley, oats and canola). Of these, 14 species already present in Québec as well as 24 alien species could be affected by the climate changes anticipated in Québec and were the subject of a detailed literature review. Twelve summary sheets were also produced for the alien species most likely to become established in Québec in the future. These documents were made available to agricultural advisors and farmers on the Agri-Réseau website.

Three insects (brown marmorated stink bug, tomato fruitworm and southern green stink bug) were the subject of a detailed analysis to model the impacts of climate change and identify adaptation solutions. Unlike the other two species, adult brown marmorated stink bugs have been captured in Montérégie and Montreal since 2015.

Given the temperature requirements of the brown marmorated stink bug, it appears that their presence can be explained by the accidental introduction of specimens by road transport and merchandise from more southern regions since the species would not have found the conditions necessary to complete their cycle in recent decades in Québec (Figure1).

Figure 1. Average peak appearance dates for the first generation of adult brown marmorated stink bug for the 1981-2010 period

Due to projected temperature increases, these three insects have the potential to become established in Québec by 2041-2070. They would be able to complete at least one development cycle because the duration of each stage of development would be shortened. These three species are most likely to become established in the Montérégie region and, in the case of the brown marmorated stink bug, its range could even extend as far as the Capitale-Nationale region (Figure 2).

Figure 2. Average peak appearance dates for the first generation of adult brown marmorated stink bug: high change scenario (2041-2070)

Thus, the brown marmorated stink bug could complete its first generation and reach the adult stage as early as September, before the first autumn frost, especially since the frost will be delayed due to climate change. These insects could therefore become more problematic for Québec farmers.

Several solutions will help farmers to adapt and effectively fight against the introduction and expansion of the range of certain insects and diseases that will result from future climate change

Here are a few examples:

• Biomonitoring with upgraded networks and screening methods, including better networking and monitoring of what is happening in neighbouring Canadian provinces and U.S. states, as well as the use of citizen science tools to track the changing range of invasive alien species;

• Developing a good knowledge of these new plant pests, in terms of both their biology and environmentally friendly control methods (e.g. mass capture traps, exclusion nets, resistant varieties), in order to be able to react quickly and thus limit the progression of pests and damage to crops.

• Agriculture et agroalimentaire Canada

• Ministère de l’agriculture, des Pêcheries et de l’Alimentation

• Université de Montréal

• Producteurs de grains du Québec