Cropping system adaptation for enhanced resilience to climate change in cold climate regions

Climate change is affecting our global environment and every sector of our economy. Yet, the agricultural sector stands out as being disproportionately impacted. Rising global temperatures are stressful for growing crops. As the Earth warms, the weather is expected to become increasingly erratic and extreme weather events are likely to occur more frequently. Crops are at risk from drought, flooding, heat waves, and the damaging effects of frost, hail, windstorms, and rainstorms. This special issue in the Canadian Journal of Plant Science covers all aspects of cropping system research in cold climate regions. The articles selected for publication in this special issue examine how cultivar selection and cropping system management can address the challenges and opportunities of a changing climate. Our goal was to gather the most current findings that would help explain the variability in crop responses, according to the geographical location (Mapfumo et al. 2023a, 2023b; Qian et al. 2023). Another objective was to identify the plant attributes that could enhance the resilience of cropping systems to climate change. Finally, we examined how crop adaptation and agricultural management could maintain or improve crop yields, ensure food security, and protect the environment. Crop breeding is one way to adapt to stressful growing conditions. Heat stress and water deficit are major growthlimiting factors for cool season crops such as field pea (Pisum sativum L). We now understand that lower yields of heat stressed pea is the result of early embryo abortion rather than difficulties with pollination (Osorio et al. 2023). Heat tolerance in field pea is associated with quantitative trait locus on chromosomes 2, 5, and 7 (Huang et al. 2023), which assists efforts to identify genotypes with superior heat stress tolerance. There is also a genetic and molecular basis to understanding soybean (Glycine max L.) seed germination in response to waterlogging and cold climate (Suo et al. 2023). Genetic adaptability will also be critical to the selection of forage crops such as cicer milkvetch (Astragalus cicer L.), a non-bloat perennial forage legume that thrives in colder climates and produces high yields of digestible livestock feed in the colder months (MacTaggart et al. 2023). Cropping system management will be key to sustaining the yields of short-season oilseed crops like soybean, which are sensitive to water limitation and solar radiation (Cober and Morrison 2023). Including perennial forages, as seed crops, in crop rotations is an option for greater cropping system resiliency in cold climate agricultural regions (Khanal 2023), while drought-resistant cover crops also offer additional opportunities for maintaining soil cover and fertility in dryland agriculture (Ben Kalifa et al. 2023). Soil fertility in potato (Solanum tuberosum L.) production systems was improved through the application of woody mulch (Nyiraneza et al. 2023), whereas judicious use of nitrogen fertilizers improved the yield of spring and winter wheat (Biswas et al. 2023; Owens et al. 2023; Wang et al. 2023). Minimizing the climatic stress experienced by perennial crops is the focus of several articles in this special issue. Since commercial apple trees (Malus domestica Borkh.) are productive for 15–25 years, one way to sustain high marketable yields in a changing climate is to graft apple scions onto superior rootstock, as a means of preventing sunburn on the apple (Xu et al. 2023). Another option to avoid sunburn is to spray the fruit with calcium-carbonate-based foliar protectants (Hannam and MacDonald 2023). Sweet cherry trees (Prunus avium L.) respond positively to postharvest deficit irrigation, a water conservation method, with regard to their growth, productivity, and metabolic capacity (Houghton et al. 2023a, 2023b). In summary, manuscripts in this special issue help bridge our current knowledge gap related to cropping system adaptation for enhanced resilience to climate change in cold climate regions. This issue also identifies novel cultivars and modified cropping systems with good potential to sustain the production of nutritious, high-yielding crops, thereby securing a reliable food supply for the health of people and our planet.