2.11 Determination of CI Index
Internal browning (IB) is a characteristic symptom of CI in peach fruit. IB was visually estimated after cutting along the axial diameter of 10 fruits per replicate. The estimates were in turn used to calculate the CI index (Wang et al., 2013). CI severity scores range from 0 to 4: 0 = No IB observed, 1 = Mild, 2 = Moderate, 3 = Moderately Severe, 4 = Severe. The CI index was calculated using the formula: CI index = [(CI score) × (number of fruits with this CI score)] /(4 × total number of fruits in each treatment).