Rhinoceros beetle monitoring with pheromone traps: how Chemiseed RB Lure works in oil palm and coconut
Rhinoceros beetle monitoring with pheromone traps
How ethyl 4-methyloctanoate pheromone lures are used within integrated pest management in oil palm and coconut, for the Asian rhinoceros beetle (Oryctes rhinoceros) and the African rhinoceros beetle (Oryctes monoceros). By Chemiseed Sdn. Bhd.
The rhinoceros beetle problem
Oryctes rhinoceros adults bore into the growing point (spear leaf) of oil palm and coconut palms. In young palms, boring damage can kill palms outright; in older palms, repeated attacks damage the fronds. Larvae breed in decomposing palm trunks, wood chip piles and EFB mulch, which is why beetle pressure peaks during and after replanting.
How pheromone trapping works
Deploy traps
Traps hang along palm rows near breeding material. In Malaysia, vaned bucket traps caught beetles more efficiently than pitfall and barrier traps (Hallett et al. 1995, as reported in Paudel et al. 2023). Set the lure as described in the instructions supplied with it.
Attract and capture
The pheromone plume attracts adult beetles, which enter the trap and fall into the collection bucket, so the catch serves both monitoring and mass trapping. Adding freshly rotting oil palm fruit bunches to pheromone traps increased catches (Hallett et al. 1995).
Monitor and replace
Check traps regularly and count the catch to follow the population trend. Replace sachets at the interval in the manufacturer's instructions. Sachet life depends on the weather: in India it was reported as about 5 months in the wet monsoon and 3 to 4 months in summer (Jayanth et al. 2009, as reported in Paudel et al. 2023).
Chemiseed RB Lure specifications
| Specification | Detail |
|---|---|
| Active compound | Ethyl 4-methyloctanoate, the aggregation pheromone of Oryctes rhinoceros (Hallett et al. 1995) and of Oryctes monoceros (Gries et al. 1994) |
| Form | Slow-release sachet |
| Trap density | One trap per 2 hectares is the density recommended for general monitoring in Malaysian oil palm (Chung 1997; Kamarudin et al. 2007; as reported in Paudel et al. 2023) |
| Sachets per trap and replacement interval | As set out in the manufacturer's instructions supplied with the order |
| Target pests | Oryctes rhinoceros; Oryctes monoceros (see the section below for what is and is not shown) |
| Manufactured for | Chemiseed Sdn. Bhd., by ChemTica International, S.A., Costa Rica |
| Supply | Chemiseed Sdn. Bhd. is the exclusive supplier for Asia; supply to buyers in Africa and other regions is by quotation |
| Handling | A pheromone, not an insecticide: it hangs inside the trap and is never sprayed on the palm. Handle and store it as the safety data sheet says. |
Pheromone trapping in IPM context
Cultural control
Manage breeding sites: chip, burn or treat old palm trunks, and manage EFB mulch piles and decomposing organic matter.
Biological control
Oryctes rhinoceros nudivirus (OrNV) and Metarhizium majus are biological agents used in some regions. Effectiveness varies.
Pheromone trapping
Mass trapping with aggregation pheromone lures, started early in replanting and kept up consistently. In a Malaysian study, one trap per 2 ha reduced damage at five of six sites but not at the sixth (Chung 1997, as reported in Paudel et al. 2023).
Physical protection
Wire netting around young palm spear leaves can physically exclude beetles during the most vulnerable establishment period.
African rhinoceros beetle (Oryctes monoceros)
Oryctes monoceros is the rhinoceros beetle of tropical Africa, a pest of coconut and oil palm. Allou et al. (2006) describe it as the most serious pest in coconut plantations, causing up to 40% damage in tropical Africa, especially in Côte d'Ivoire. Like the Asian species, it breeds in rotting palm trunks and other decaying palm material.
Does the RB Lure pheromone attract it?
Yes, the active compound does. Gries et al. (1994) identified ethyl 4-methyloctanoate as a male-produced aggregation pheromone of O. monoceros, and in a field trial in Côte d'Ivoire the synthetic compound attracted both male and female beetles, while ethyl chrysanthemate, an older attractant, caught none.
Trapping results in Côte d'Ivoire
Allou et al. (2006) tested ethyl 4-methyloctanoate with decaying palm material in Côte d'Ivoire. Palm material (oil palm empty fruit bunches or pieces of coconut wood) caught nothing on its own but increased catches with the pheromone, and coconut wood worked better than empty fruit bunches. Vertical PVC tube traps set in the soil caught more than 30-litre pail traps hung 1.5 m above the ground. A related compound, 4-methyloctanoic acid, reduced catches when added at more than 10%. In a 19-hectare coconut plot inside a 4,000-hectare oil palm estate, trapping over six months in 2002 and in 2003 was followed by damage falling from 3.8% in 2001 to 0.5% in 2002 and 0.2% in 2003; with routine trapping in 2004, 32 traps caught 3,369 beetles in nine months and damage was 0.0%.
Which beetles the traps catch
In a follow-up study, traps baited with pheromone and rotting palm material caught 43% females, and 96% of the trapped females had mated and were sexually mature. On living palms, 46% of the females in feeding galleries were immature. The authors conclude that the traps help reduce the spread of egg-laying females but do not directly reduce the number of immature beetles attacking palms (Allou et al. 2008).
Timing in Nigerian replants
At Ubima, Rivers State, Nigeria, adult O. monoceros collected by hand in three replanting cycles (2018, 2020 and 2022) peaked between 18 and 25 months after planting (Riley et al. 2026). The study used hand collection, not pheromone traps. The authors recommend good cover crops, chipping or shredding felled trunks, biological control and continued monitoring.
What is shown and what is not
- Shown: ethyl 4-methyloctanoate attracts male and female O. monoceros in the field (Gries et al. 1994).
- Shown: in one coconut plot in Côte d'Ivoire, damage fell from 3.8% to zero over three years of pheromone trapping with palm material, 2002 to 2004 (Allou et al. 2006). The abstract reports the trend over time; it does not report an untrapped comparison plot.
- Not shown: we know of no published trial of RB Lure itself against O. monoceros. The trap that worked best in Côte d'Ivoire (a tube trap set in the soil, baited with coconut wood) differs from the raised vane traps used against O. rhinoceros in Asia, so trap design for Africa should follow the African work.
- Not shown: that pheromone trapping on its own protects oil palm replants in Nigeria; the Nigerian study used hand collection.
Ordering RB Lure for Africa
Supply to Africa is by quotation from Malaysia: payment in full before dispatch, Ex Works (EXW) Selangor unless the quotation names FOB or CIF, and the minimum order and lead time confirmed on the quotation. A pheromone lure may need registration with the national pesticide or agrochemical authority before it can be imported or sold; the importer confirms this before ordering.
Buyers in Africa: Nigeria | Ghana | Côte d'Ivoire | Cameroon
Cover crops and beetle management
Whether a legume cover reduces beetle breeding is still a field question. Researchers working on O. monoceros in Nigerian replants suggest that a well-established legume cover that hides rotting trunks is worth testing, citing earlier work, and list good cover crops among their recommendations (Riley et al. 2026). We offer Mucuna bracteata and the other cover crops for their soil benefits, not as a way to reduce beetle numbers. See cover crops for Africa.
What pheromone trapping does not do
Important limitations
Trapping reduces adult numbers but does not eliminate the population. It works best as part of integrated management. Trapping does not address larvae in decomposing organic matter, so breeding-site management is essential. Trap effectiveness depends on proper deployment, regular sachet replacement and consistent monitoring.
Frequently asked questions
How many traps do I need?
When should I start deploying traps?
Can traps replace insecticide?
Are pheromone traps safe?
Can I order RB Lure in Africa?
References
- Hallett, R.H., Perez, A.L., Gries, G., Gries, R., Pierce, H.D. Jr, Yue, J., Oehlschlager, A.C., Gonzalez, L.M. and Borden, J.H. (1995). Aggregation pheromone of coconut rhinoceros beetle, Oryctes rhinoceros (L.) (Coleoptera: Scarabaeidae). Journal of Chemical Ecology 21(10): 1549-1570. doi:10.1007/BF02035152
- Paudel, S., Jackson, T.A., Mansfield, S., Ero, M., Moore, A. and Marshall, S.D.G. (2023). Use of pheromones for monitoring and control strategies of coconut rhinoceros beetle (Oryctes rhinoceros): a review. Crop Protection 174: 106400. doi:10.1016/j.cropro.2023.106400
- Chung, G.F. (1997). The bioefficacy of the aggregation pheromone in mass trapping of rhinoceros beetles (Oryctes rhinoceros L.) in Malaysia. The Planter 73(852): 119-127 (as reported in Paudel et al. 2023).
- Gries, G., Gries, R., Perez, A.L., Oehlschlager, A.C., Gonzalez, L.M., Pierce, H.D. Jr, Zebeyou, M. and Kouame, B. (1994). Aggregation pheromone of the African rhinoceros beetle, Oryctes monoceros (Olivier) (Coleoptera: Scarabaeidae). Zeitschrift für Naturforschung C 49(5-6): 363-366. doi:10.1515/znc-1994-5-614
- Allou, K., Morin, J.-P., Kouassi, P., N'klo, F.H. and Rochat, D. (2006). Oryctes monoceros trapping with synthetic pheromone and palm material in Ivory Coast. Journal of Chemical Ecology 32(8): 1743-1754. doi:10.1007/s10886-006-9106-z
- Allou, K., Morin, J.-P., Kouassi, P., Hala N'klo, F. and Rochat, D. (2008). Sex ratio and female sexual status of the coconut pest, Oryctes monoceros (Coleoptera: Dynastidae), differ in feeding galleries and pheromone-baited traps. Bulletin of Entomological Research 98: 581-586. doi:10.1017/S0007485308005890
- Riley, S.O., Wiafe, E.K., Impens, R., Beaudoin-Ollivier, L., Samuel, D.O., Okoye, G. and Sule, B.A. (2026). Temporal patterns of Oryctes monoceros (Olivier) (Coleoptera: Scarabaeidae: Dynastinae) in oil palm replanting: a study across three cycles. OCL 33: 8. doi:10.1051/ocl/2025042
Need pheromone lures for rhinoceros beetle management?
Contact Chemiseed Sdn. Bhd. for an RB Lure quotation and deployment guidance for your plantation.
Buyers in Africa: Nigeria | Ghana | Côte d'Ivoire | Cameroon