- T. Grove1, W. Steyn1, M. de Beer1 and P.J.G. Booysen2
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1Institute for Tropical and Subtropical Crops, Private Bag XI 1208, Nelspruit 1200
2Insect Science SA, Private Bag X4019, Suite 378, Tzaneen 0850 - 2002
The false codling moth, Cryptophlebia leucotreta (Meyrick) (Lepidoptera: Tortricidae) is a pest of litchi, Litchi chinensis Sonnerat in South Africa. Eggs are laid on the fruit and newly hatched larvae eat through the skin and into fruit flesh and seed. In this study an attract and kill product, Last Call F.C.M. was tested for the control of C. leucotreta in litchi orchards. The trial was carried out on Friedenheim farm of the ARC-Institute for Tropical and Subtropical Crops situated near Nelspruit. Two hectares of the cultivar HLH Mauritius were used. One hectare was treated with Last Call F.C.M. 0.4% pheromone and 6% permethrin insecticide. The number of eggs and larvae infesting fruit in the treated and control plots were determined weekly. Last Call F.C.M. was able to reduce percentage of damage on litchi fruit. Adult moths trapped in the treated plot were less than in the control plot and it was concluded that Last Call F.C.M. shows potential as a controlling agent for C. leucotreta. In this experiment C. leucotreta was the only moth for which an insecticide was applied. Damage could have been less if C. peltastica was also addressed. Future research must aim at the development of a similar product for controlling C. peltastica.
Summary:
The false codling moth (FCM), Cryptophlebia leucotreta, is a significant pest of litchi in South Africa, causing damage by larvae burrowing into fruit after eggs are laid on fruit skin.
This study tested an attract-and-kill product called Last Call F.C.M. which combines specific synthetic pheromones with a small amount of insecticide (permethrin) to control FCM in litchi orchards.
The trial was conducted on two hectares of HLH Mauritius cultivar at ARC’s Friedenheim farm near Nelspruit, with one hectare treated with Last Call and the other as a control.
Last Call pheromone formulation contained E-7-dodecenyl acetate, E-8-dodecenyl acetate, and Z-8-dodecenyl acetate in a 65:1 ratio and was applied in droplets on leaves.
The product attracted male moths, which then contacted the insecticide and were killed or incapacitated, reducing mating and subsequent populations.
Trapping showed a significant drop in adult moth numbers in the treated plot compared to the control, with moth numbers falling to zero shortly after application.
Fruit damage assessments showed Last Call reduced egg and larval infestation in treated areas compared to control, though variations in significance were noted at different sampling times.
Last Call F.C.M. has no harmful effects on natural enemies of moth pests and leaves no harmful residues on fruit, making it a safer alternative to conventional insecticides.
The study recommends the development of a similar pheromone-based control product for the litchi moth Cryptophlebia peltastica for comprehensive pest management.
Overall, Last Call F.C.M. shows promise as an effective, environmentally friendly control method for false codling moth in litchi production, aligning with global trends away from harsh chemical pesticides.