Eudocima fullonia (fruit-piercing moth)

Adults of E. fullonia feed on the juices of fruit by penetrating the skin or rind with a strong, barbed proboscis (Cochereau, 1977). One or more neat, pinhole-sized holes are the first external signs of attack. Juice often weeps from the feeding holes, and can discolour the surrounding fruit. The damaged tissue beneath the skin tends to be disturbed, honeycombed and spongy. Fruit-rotting moulds, such as Oospora spp. and Fusarium spp., soon invade the wound causing rapid breakdown (and fermentation). In crops such as citrus, this is manifested as a large discoloured patch surrounding the feeding site. Fruit fall is common in some crops, particularly in citrus, and is an early symptom of fruit-piercing moth activity. Secondary sucking species frequently visit damaged fruit.

Introduction

The various means attempted or proposed to control fruit-piercing moths have been discussed by Baptist (1944), Banziger (1982), Dodia et al. (1986), Waterhouse and Norris (1987), and Fay and Halfpapp (1991).

Cultural Methods

- The collection and destruction of rotting or fallen fruit may have some limited effect on E. fullonia when populations are low, and will reduce the numbers of secondary moths.

- Early harvest of fruit, particularly in outbreak years, will help to reduce damage levels. However, industry-imposed maturity standards may not permit such an approach.

- Fay and Halfpapp (1993a) recommended that crops be planted in square blocks, rather than in a few long rows, as most fruit-piercing moth attacks occur along the outer edges of crops. This should limit the damage to fewer plants.

- A trap or decoy crop which is known to be highly attractive to E. fullonia could be employed as a peripheral crop to dilute the number of moths penetrating to the more valued central crop.

- Populations of E. fullonia diminish seasonally in many areas, and this offers opportunities for the production of commodities in the absence of moth activity (Fay and Halfpapp, 1993b).

- Where possible and practical, the removal of plants that are hosts of larvae within the vicinity of susceptible crops will reduce the incidence of fruit-piercing moth.

In those countries in which more than one species of Eudocima exist, it is difficult to stipulate the proportion of fruit lost to E. fullonia. However, in Thailand Banziger (1982) reported that E. fullonia caused an estimated 70-90% and 50-70% of primary damage inflicted by fruit-piercing moths on longan and citrus, respectively. In north-east Australia, an average 88.8% of moths inflicting damage on lychees and carambolas were E. fullonia (Fay and Halfpapp, 1993a). In drier tropical areas, Eudocima materna seems to increase in prominence (Younghusband, 1979; Fay and Halfpapp, 1993b).Although losses of fruit to E. fullonia in New Caledonia are minor in regular years, 95% of citrus and 100% of tomatoes have been damaged in outbreak years (Waterhouse and Norris, 1987). In Fiji, 10 to 15% of ripe fruit (primarily citrus) was regularly lost to E. fullonia, rising as high as 73% (Waterhouse and Norris, 1987). Crop losses to fruit-piercing moths of more than 50% have been reported by Fay (1996) in Australia, and in crops such as lychees most can be attributed to E. fullonia. Irregular outbreaks of E. fullonia have threatened entire crops of navel oranges in south-east Queensland (Fay, 1997). Similarly, surveys in parts of China have found 40-60% of citrus fruits damaged by E. fullonia (Cai and Geng, 1997). In Maharashtra, India, Mote et al. (1991) reported up to 57% of pomegranate fruit suffered damage by fruit-piercing moths, including E. fullonia.Failure to detect fruit-piercing moth damage at harvest or packing can result in sound fruit being contaminated by fermenting juices during shipment. Whole boxes or cartons of fruit may then be lost. The economic impact of fruit-piercing moths is often masked by the emphasis placed on fruit flies, some of which occasionally utilize fruit-piercing moth wounds for oviposition.