Pg. 25-29 Effect of the time of bagging Wai Chee litchi (Litchi chinensis) fruit bunches after fruit-set on fruit appeal and the incidence of litchi moth infestation at harvest

The effect of the time of bagging litchi fruit bunches after fruit-set on fruit appeal and the incidence of litchi moth infestation at harvest was assessed in the cultivar, Wai Chee. Specifically designed, white, coated paper bags, were used. Bunches were bagged on November 10, 17, 24 or December 1, 2006, during the period when litchi moth infestation would be expected to occur. On November 1 O the fruits were 8 to 1 O mm in length, initial set having occurred three to four weeks earlier. The litchi bunches were harvested on January 5, 2007, and evaluated on January 5 and 6. Fruit number, individual weight, litchi moth infestation incidence, skin colouration, juice total soluble solids content, taste, and surface blemish incidence and severity, were assessed. 

The litchi bunches bagged on November 10 or November 17, were devoid of litchi moth effects. Some infestation was noted on the fruit bunches bagged on the later dates. Slight reductions in fruit retention, fruit weight, total soluble solids content, intense skin colouration and taste appeal generally resulted from bagging, these effects generally being least in the bunches bagged on November 10. Bagging affecting maturation rate may have been the reason for the foregoing effects. Fruit blemish at harvest, which gives rise to fruit exclusion during packing, was markedly reduced in the bagged bunches. The data indicate that bagging is a viable option to prevent pests such as litchi moth from gaining access to the fruits. Earlier as opposed to later bagging, relative to the time of fruit set, was indicated to be more effective in this regard. Prevention of fruit fly access would also be expected. Fruit fly damage was not noted in the present study.