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| Trait | Measurement |
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| Origin | Countries were given codes ranging from 1 to 13. Australia had code 1, Canada 2, England 3, Israel 4, Denmark 5, France 6, South Africa 7, Russia 8, USA 9, Zimbabwe 10, Ireland 11, and Germany 12. |
| Fruit shape | Measured on a score of 1.0–5.2 (Figure 1). |
| Fruit size | Measured in comparison to reference cultivars and on a score of 1–9 (Figure 1): a score of 1 showing an extremely small fruit and 9 showing an extremely large fruit. |
| Ground colour | The ground colour was determined on the ground colour of the skin of a fully mature fruit. It was measured on the score of 1–6: a score of 1 represented red colour, 2 orange, 3 cream-white, 4 yellow, 5 green-yellow, and 6 green. |
| Overcolour | Overcolour of the skin of a fully mature fruit was determined on score of 1–6, where 1 represented orange, 2 pink, 3 red, 4 dark red, 5 purple, and 6 brown |
| Fruit attractiveness | Fruit attractiveness was determined subjectively as it varies between regions and experts and was scored on a scale of 1–9 with a score of 1 indicating extremely poor and reference cultivar being Egremont Russet and 9 showing extremely good and the reference cultivar being the Discovery. |
| Type of overcolour | Type of overcolour was determined on the score of 1–8. The score of 1 represented striped, 2 streaked, 3 mottled, 4 splashed, 5 slightly blushed, 6 washed out (faded), 7 complete overcolour, and 8 others. |
| Russet type | Measured on a scale of 1–9: a score of 1 represented extremely fine, 2 very fine, 4 intermediate, 6 coarse, 8 scaly, and 9 cracked. |
| Russet amount | Measured as a percentage of fruit surface russetted. Russet amount was scored on a scale of 1–9: a score of 1 represented 0%, 2 represented 12%, 3 stood for 25%, 4 for 37%, 5 for 50%, 6 for 62%, 7 for 75%, 8 for 87%, and 9 for 100% russet. |
| Eating quality dessert | This was measured through a qualitative combined assessment of flavour, acidity, sweetness, aroma, and astringency at the optimum time of eating. This was scored on a scale of 1–9 where a score of 1 reflected the extremely poor eating quality and 9 showed extremely good eating quality. |
| Bitter pit susceptibility | This was determined by randomly sampling 10 fruits per cultivar in the field and observing if they had bitter pit. A score of 0–9 was used, where a score of 0 depicted absence of bitter pit whereas 9 indicated extreme severity. |
| Bruising susceptibility | Bruising susceptibility was determined by observing the condition of a fully mature fruit in a storage tray. It was measured on a scale of 1–9, where a score of 1 indicated extremely slight bruising while 9 showed extremely high susceptibility to bruising. |
| Firmness without skin | Fruit firmness without skin was recorded in kilograms on fruit that was just ripe on a part of the fruit from which the outer skin had been removed using a penetrometer that had an 8 mm probe. The pressure required to penetrate was scored on a 1–5 scale where 1 indicated extreme softness and 5 showed extreme firmness with reference cultivar being Granny Smith. |
| Texture | This was measured on the basis of the texture of the flesh of a ripe fruit. It was scored on a score of 1–9 with a score of 1 representing extremely coarse flesh and 9 showing extremely fine texture. |
| Maximum storage life | Maximum storage life was determined through keeping 5 of each fruit type at room temperature and observing which one deteriorated first, and a score of 1–9 was assigned: a score of 1 indicating extremely poor maximum storage life while 9 indicated extremely good maximum storage life at room temperature. |
| Pest susceptibility | Pest susceptibility was determined through the presence of key apple pests on the plants such as apple woolly aphid, codling moth, and the rosy apple aphid. The presence of the apple woolly aphid was given a score of 8, codling moth a score of 9, and rosy apple aphid a score of 10 |
| Fungi susceptibility | Fungi susceptibility was determined on the presence of certain types of fungi on a score of 1–3. A score of 1 indicated presence of Podosphera laucotricha (mildew), 2 presence of Venturia inaequalis (scab), and 3 Nectria galligena (canker), Phytophthora cactorum (collar rot and root rot) |
| Tree habit | Measured on the basis of the natural habit of branches of the untrained tree and a score of 1–9 with a score of 1 indicating extremely upright, 5 indicting spreading habit, 7 showing drooping habit, and 9 reflecting a weeping habit. |
| Tree vigour | Measured on a score of 1–9 with a score of 1 reflecting extreme weakness and 9 showing extreme vigour based on reference cultivars. |
| Flowering period | Measured on a score of 1–9 with a score of 1 indicating extremely early and 9 showing extremely late. |
| Regularity of flowering | Measured on a score of 1–9 with a score of 1 indicating extremely irregular, 5 showing biennialism, and 9 reflecting extremely regular flowering habit. |
| Secondary flowering | Measured on a score of 1–9 with a score of 1 indicating extremely rare, 7 showing frequent, and 9 reflecting extremely frequent secondary flowering. |
| Self-compatibility | Assessed by artificially self-pollinating flowers on a tree. The outcome was grouped as self-compatible when fruits set or self-incompatible when fruits do not set. |
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