Climate Change and Chilling Requirements

Abstract

Climate change has affected the rates of chilling and heat accumulation, which are vital for flowering and production, in temperate fruit trees (Guo et al. 2014). All economically important fruit and nut tree species that originated from temperate and cool subtropical regions have chilling requirements that need to be fulfilled each winter to ensure homogeneous flowering and fruit set, and generate economically sufficient yields (Westwood 1993; Luedeling et al. 2009a; Luedeling and Brown 2011). Reduced winter chill is likely to have the most severe consequences for fruit production (Luedeling et al. 2011; Darbyshire et al. 2013). This chronic and steady reduction in winter chilling is expected to have deleterious economic impact on fruit and nut production in California, USA by the end of the 21st Century.