The following data is based off of Pew Research's "The 10 largest refugee crises in recent times (since 1960), by number and population share." Note: Ukraine's refugee count and population share values are updated to reflect counts as of April 12, 2022 from the UNHCR. (End dates that are blank are ongoing events.)
Russia and Ukraine are both in the top 5 global wheat exporters
In 2019 together they were responsible for 25% of wheat exports. In Axios, Nathan Bomey highlights what this means for global wheat prices.