Pg. 55-58 Evaluation of synthetic sex pheromones and control methods for Cryptophlebia species (Lepidoptera: Tortricidae) in litchi orchards

The litchi moth, Cryptophlebia peltastica (Meyrick) (Lepidoptera: Tortricidae) and the false codling moth, Cryptophlebia leucotreta (Meyrick) (Lepidoptera: Tortricidae) are pests of litchi, Litchi chinensis Sonnerat in South Africa. Both species are similar in appearance and eggs are laid on the skin of the fruit and newly hatched larvae eat through the skin and into fruit flesh and seed. The aim of the present study was to test field responses of Cryptophlebia males to different synthetic female pheromones. Trials were carried out in litchi orchards in the Nelspruit and Tzaneen areas. Yellow delta traps with sticky liners were used in combination with the pheromones. Different control methods were also evaluated in the study which included: fenpropathrin (Meothrin, Philagro South Africa), triflumuron (Alsystin, Bayer CropScience), a granulovirus (Cryptex, Biological Control Products SA [Pty] Ltd) and bags (Bridspun, Cape Agricultural Products [Pty] Ltd). Infestation levels in different production areas were assessed. The LFM PheroLure 1 (Insect Science SA) was the most effective pheromone for C peltastica in both areas. Results from the Nelspruit area indicated that Chempack FCM Lure (Chempack [Pty] Ltd) attracted the highest number of C leucotreta while at Tzaneen the FCM PheroLure (Insect Science SA) was the most effective. The MNB PheroLure (Insect Science SA) was the most effective for C. batrachopa at both locations. Birdspun was the most effective control method but the method is not practical. The highest infestation level found was 12% in an orchard consisting of different selection and cultivars. Future research must address the need of alternative control methods and the pheromone identified for monitoring of C peltastica
will contribute towards understanding the population dynamics of the pest.

Summary:

• The study evaluated synthetic sex pheromones and control methods for three Cryptophlebia moth species (C. peltastica, C. leucotreta, C. batrachopa) that infest litchi orchards in South Africa.
• Field trials were conducted in litchi orchards in Nelspruit and Tzaneen areas using yellow delta traps with sticky liners baited with different synthetic female pheromones.
• The LFM PheroLure 1 pheromone was found to be the most effective in attracting male C. peltastica in both trial areas, outperforming previously used pheromones.
• For C. leucotreta, the Chempack FCM Lure was most effective in Nelspruit, while FCM PheroLure was best in Tzaneen.
• The MNB PheroLure was the most effective pheromone for C. batrachopa at both locations.
• Several control methods were tested in the Nelspruit orchard: insecticides fenpropathrin and triflumuron, a granulovirus biological control product, and physical fruit bagging using Birdspun bags.
• Birdspun bags provided the best control but were impractical due to labor intensity, fruit damage, and moisture issues.
• Fenpropathrin and triflumuron reduced infestation levels but alternative control methods are still needed.
• Cryptophlebia peltastica was the dominant pest species found in fruit samples; no C. batrachopa larvae were found despite traps catching some adults.
• Infestation levels varied by location, with the highest level (12%) recorded at the ITSC Nelspruit experimental farm.
• The newly identified pheromone for C. peltastica offers potential for improved pest monitoring and understanding population dynamics.
• Future research should focus on developing alternative control methods and refining pheromone-based monitoring.