Effects of adverse environmental factors on fruit set in a peach and apricot cultivar evaluation orchard

In light of the recently recorded serious concerns for the fruit and vegetable production due to weather-induced failing yields, our study approaches the possible causes of reduced yields in stone fruit cultivars. Observations on the flowering phenology and fruit set/yield together with measurements of chilling accumulation, daily temperatures and rainfall were made in a cultivar evaluation orchard of 71 peach cultivars and 21 apricot cultivars, during the spring period of 2018 when significant yield reductions registered in the broader regions of Northern Greece. Results showed that winter chilling accumulation, days with high temperatures (>20°C) during flowering, blooming time and duration were comparable to previous normal producing years. A high negative correlation was found between blooming time and % fruit set/yield in the studied peach and apricot cultivars. The yield reduction in the later flowering cultivars may have resulted due to a 4-day rainfall event with a total of 50 mm, and subsequent temperature drop, inducing a disruption in the pollination procedure. The present study provides an insight on understanding the vulnerable environmental parameters for peach and apricot yield.