Fruit bagging, a useful method for studying anthocyanin synthesis and gene expression in apples

'Delicious' fruits were covered with one-, two-, or three-layered paper bags from the early development stage until harvest. Bagging did not affect fruit maturity but significantly inhibited anthocyanin accumulation in fruit peel. Fruits from one- or two-layer-bag treatments accumulated certain amount of anthocyanin, but no anthocyanin and only low level of other phenolics were accumulated in fruit peel in the three-layer-bag treatment. When fruits treated with three-layered bags were exposed to light, they started to accumulate anthocyanin rapidly and anthocyanin accumulation reached maximum after 3 days of light exposure. The capability of anthocyanin synthesis in fruits remained constant during 5 months of cold storage. Results indicate that these fruits could be a useful model in the research on anthocyanin synthesis and gene expression in apples. (C) 1998 Elsevier Science B.V. All rights reserved.