Fig. 3C. The use of black patch method to induce sunburn in Gala apples. Apple on the left photo was heated to 126°F and apple on the right was heated to 122°F for 10 min. Photos A, B, and C were taken 1, 4, and 7 days after heating
Image from the Plant Management Network Image Collections.
Source: Plant Health Progress - Two Types of Sunburn in Apple Caused by High Fruit Surface (Peel) Temperature
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