Effect of abiotic stresses on Brassica rapa production in Korea: Learning from history to better prepare for the future impacts of climate change

Brassica rapa, known as Kimchi cabbage, is an important cash crop in South Korea. However, climate change has inflicted major abiotic stresses on cabbage production, resulting in physiological effects that often decrease yield and quality. To overcome these challenges, the effects of individual stresses on cabbage production must be investigated through simulation modeling and other approaches. In this study, we aim to clarify the historical and future patterns of abiotic stress to assess its effects on cabbage production in Korea. To this end, different stress index models were adopted and compared to estimate the occurrence patterns of each abiotic stress and assess their impacts on cabbage production. Our machine-learning modeling analyses revealed that approximately 62% of the variation in historical cabbage productivity can be attributed to individual abiotic stresses. The relative impact of each stress on productivity has not changed significantly over the past 40 years (1981–2020), with slight increasing or decreasing trends in major stresses. Among the abiotic stresses, the low-temperature injury and wetness stress have largely affected the cabbage productivity by 2020, followed by drought, high-temperature injury (HTI), and frost stresses. Projections based on future climate change scenarios suggest a substantial increase in HTI stress, surpassing the levels observed over the past 40 years, while other stressors are expected to either persist at similar levels, or decrease or increase slightly. This study underscores the increasing need to effectively manage these stressors, particularly those that have a greater impact on productivity and are projected to exceed their historical ranges, in order to ensure the successful future production of cabbage in Korea.