Pre-harvest fruit bagging: a useful approach for plant protection and improved post-harvest fruit quality - a review

Several good agricultural practices (GAP) are becoming popular throughout the World for the production of high quality fruit with less dependence on man-made chemicals. Among such practices, pre-harvest fruit bagging has emerged as an effective method. Bagging is a physical protection method which not only improves the visual quality of fruit by promoting skin colouration and reducing blemishes, but can also change the micro-environment for fruit development, which can have several beneficial effects on internal fruit quality. Pre-harvest bagging of fruit can also reduce the incidence of disease, insect pest and/or mechanical damage, sunburn of the skin, fruit cracking, agrochemical residues on the fruit, and bird damage. Due to its many beneficial effects, fruit bagging has become an integral part of peach, apple, pear, grape, and loquat cultivation in Japan, Australia, China and the USA. Moreover, countries such as Mexico, Chile, and Argentina do not import apples unless they are bagged. Several studies have been conducted to identify the desirable effects of pre-harvest fruit bagging on skin colour development and quality, but contradictory results have been reported. These may be due to differences in the type of bag used, the stage of fruit development when bagged, the duration of fruit exposure to natural light following bag removal, and/or fruit- and cultivar-specific responses. Bagging is laborious and its cost:benefit ratio must be investigated in order to promote adoption of the method in much of the World. The aim of this review is to improve our understanding of the beneficial effects of bagging in different fruit by collecting otherwise scattered information so that more growers could consider using this method on a commercial scale.