2018 ASHS Annual Conference

The prediction of bitter pit in ‘Honeycrisp’ apples using non-chemical methods has been investigated. Fruit from 6 different blocks in each of Hudson Valley and Western NY regions were used. Fruit were harvested at three weeks before anticipated harvest and at commercial harvest. Mineral analysis of peel tissues from the calyx-end was carried out. Replicates of fruit were either dipped or not with 2000 ppm ethephon, (2-chloroethylphosphonic acid) and bitter pit assessed at weekly intervals for 3 weeks Another set of fruit were stored at 3 °C with and without one week conditioning at 10 °C, and stored for 4 months at 3 ^oC + 7 d at 20 °C. Multivariate analysis shows that the passive method and ethephon dipping for fruit harvested 3 weeks before the anticipated harvest had higher correlation with the actual bitter pit after cold storage than those from minerals. The passive method is being further evaluated as a non-chemical predictor of bitter pit in ‘Honeycrisp’ apples.