Preharvest bagging improves packout and fruit quality of pears (Pyrus communis)

Preharvest bagging of pear fruit (Pyrus communis L. 'Doyenne du Comice') with microperforated polyethylene bags c. 30 days after full bloom increased the percentage of fruit accepted for export from 27.2 to 63.2%. This was achieved by reducing bird damage (from 28.4% for non-bagged to nil for bagged fruit) and skin blemish (with fruit rejected for export being reduced from 49.3% for non-bagged to 33.4%, for bagged fruit). Bags also reduced the level of tracery russet. Preharvest bagging reduced the damaged area of the skin at harvest from 3.15 to 1.49 cm(2)/fruit for blemishes (preharvest friction damage) and from 1.17 to 0.51 cm(2)/fruit for friction discoloration (FD; postharvest friction damage). When trees were sprayed with pesticides 3 days before harvesting, bagging reduced fruit residue of captan (non-systemic fungicide) and azinphos methyl (non-systemic insecticide) (P < 0.05). For pears submitted to mechanical damage on a commercial grader, FD area was lower for fruit left protected by the bag (6.03 cm(2)/fruit) than for non-bagged fruit (14.49 cm(2)/fruit). For fruit submitted to brush friction damage at harvest and after 8 weeks of cold storage, FD score was higher on non-bagged than on bagged fruit. Bagged fruits that had the bags removed before being submitted to brush friction damage had the same level of FD than non-bagged fruits. Preharvest use of micro-perforated polyethylene bags represents an attractive technology for the pear industry since it can reduce bird damage and skin blemishes, as well as improving fruit Postharvest quality by reducing FD and chemical residue.