Mass trapping of insect pests is done through pheromone traps. Basically, the traps and dispensers remain the same as that of monitoring, but the number of traps per unit area is increased to effectively trap more insects. In essence, monitoring is used for estimating the pest population along with resultant management decisions, whereas mass trapping is for total eradication of insect populations. Pheromone dosage in some exceptional cases is reduced to half with a view to reduce the cost of the technology. However, the number of traps and their placement is vital for efficient trapping. For instance, in the management of Anomala vitis Fabricius and Anomala dubiaScopoli placing traps on one to two outside rows caught 92% of all beetles, with ultimate reduction in damage by the grubs (Voigt and Toth, 2004).
Cryptic habits of several coleopteran borers necessitate use of pheromones for mass trapping and species such as Cosmopolites sordidus (Germar) (Rhino et al., 2010), Oryctes elegans (Tabrizian et al., 2009), Oryctes rhinoceros (Linnaeus) (Ponnamma et al., 2002), Ips acuminatus Gyllenhal (Perez and Sierra, 2006), R. ferrugineus (Soroker et al., 2005; Mohammadpur and Faghih, 2008; Jayanth et al., 2007; Guarino et al., 2013), and Xylotrechus quadripes (Chevrolet) (Jayarama et al., 2007). Mass trapping of Cylas formicarius using Z-3-dodecenyl-E−2-butenoate at 0.001–1 mg/trap was successful, ultimately resulting in good crops with reduced damage (Talekar and Lee, 1989; Setokuchi et al., 1991; Teli and Salunkhe, 1993; Yasuda, 1995; Pillai et al., 1996; Smit et al., 2001; Chiranjeevi and Reddy, 2003); however, lack of availability of synthesized pheromone in greater quantities is still a constraint for its successful mass trapping. A list of insects for which mass trapping is done using pheromones is provided in Table 2.
Leaf feeding and boring habits of lepidopterans make mass trapping using pheromones one of the most effective tools. Exploitation of sex pheromones for the management of Ephestia kuehniella (Zeller), Chilo suppressalis (Walker) (Sheng et al., 2000, 2002; Jiaoet al., 2003, 2005; Su et al., 2003), Chilo infuscatellusSnell. and Chilo sacchariphagus indicus (Bojer) (David et al., 1985; Chelvi et al., 2010), Plutella xylostella (Linnaeus), (Chow et al., 1977; Maa et al., 1987; Chisholm et al., 1979; Reddy and Urs, 1997; Wang et al., 2004; Huangfu et al., 2005), and Pectinophora gossypiella (Saunders) is in vogue. The number of traps used, however, vary from 9 traps/ha (P. gossypiella; Huber and Hoffmann, 1979; Nassef et al., 1999; Campion and Nesbitt, 1983; Neto and Habib, 1996; Ahmad and Attique, 1993; Patil et al., 2008; Nandihalli et al., 1993) to 42/ha (E. kuehniella; Trematerra and Gentile, 2010). Long-term usage of mass trapping has been known to reduce major pests, such as Cydia pomonella (Linnaeus), P. gossypiella, bark beetles, palm weevils, corn rootworm Anthonomus grandis Boheman and Lymantria dispar (Linnaeus) (El Sayed et al., 2006). However, establishment of the effectiveness of this technology requires larger plot trials.
Integrated pest management with mass trapping as one of the modules has been successful for several pests. The use of pheromones for mass trapping has led to great reduction in the pest load of many crops in India, viz. Scirpophaga incertulas(Walker), where the use of pheromone traps has led to greatly reduced pest incidence and an appreciable reduction in insecticide usage in rice (Cork et al., 2005b). In the management of brinjal, installation of 25–30 traps/ac, containing a blend of E-11-hexadecenyl acetate and E-11-hexadecenol (100:1) along with insecticidal sprays such as neem, effectively managed Leucinodes orbonalis (Guenee) (Cork et al., 2001, 2003, 2005a; Rath and Dash, 2005; Dash et al., 2005). Although the management of pests using mass trapping is largely successful, in several instances it is unsuccessful as observed in the case of Anthonomus rubi Herbst. (Cross et al., 2006). To be effective as a management tool, the use of mass trapping is suggested for longer periods of usage. For instance, continuous use of P. xylostella pheromone reduced larval and adult populations of insects in China (Huangfu et al., 2005).
The efficacy of the trap type also differs with the kind of insect targeted. Infestation of grubs of D. virgifera was dramatically reduced in soil with the use of 4-methoxy cinnamaldehyde in a cone cup (Metcalf) type trap. Use of funnel traps baited with Z-3-hexanal-1-ol with membrane dispenser reduced the infestation of Phyllopertha horticola (Linnaeus) in apple (Ruther and Mayer, 2005).
In addition, the number of traps and their placement is crucial for efficient trapping. For instance, in the management of A. vitisFabricius and A. dubia Scopoli, placing the traps on one to two outside rows caught 92% of all beetles, leading to ultimate reduction in damage by the grubs (Voigt and Toth, 2004). There is always a direct correlation between the plot size and success of mass trapping technology, for instance the mass trapping is highly successful where the treatments are imposed in bigger holdings, such as on 5 ha plots for the management of S. incertulas compared to 1 or 3 ha plots (Varma et al., 2004).
Mass trapping is especially effective in coleopterans owing to the availability of aggregation pheromone for a variety of species. Traps loaded with ferrugineol with ethyl acetate and fermenting mixture of dates and sugarcane molasses at 10/ha effectively reduced the infestation of R. ferrugineus and mixed pheromone dispensers for O. elegans and R. ferrugineus were effective against both the species (Mohammadpur and Faghih, 2008). The efficacy of pheromone in mass trapping R. ferrugineus is well documented (Jayanth et al., 2007). In India, coffee white stem borer Xylotrechus quadripes (Chevrolet) was effectively managed through the use of cross-vane traps at 10 traps/ac along with pheromone vials containing 75 mg of pheromone, 2-hydroxy-3-decanone (Jayarama et al., 2007). Bucket traps baited with pheromone and cut sugarcane attracted more Rhabdoscelus obscurus Boisduval in Guam (Reddy et al., 2005).
Although pheromones are species specific, it has often been observed that several nontarget insects, including honeybees, are trapped owing to faulty trap designs. Cross-vane traps used for coffee stem borer quite commonly trap other insects including beneficials, such as honeybees, neuropteran predators, and hymenopteran parasitoids. Appropriate technological interventions through change in trap design have significantly reduced the capture of nontarget insects (Weber et al., 2005).
In some instances, pheromones have been found not effective in mass trapping the pests. Lethmayer et al. (2004) and Cross et al. (2004) observed that population levels of A. rubi as well as damage caused did not reduce in spite of use of aggregation pheromone. Several factors that have been recognized as contributors to the failure of mass trapping are migration of populations from other regions, ineffective trap designs, insufficient number of traps, and nonadoption in wider or adjacent areas.
It is both interesting and comforting to see modern stats applied to reduction of sex pheromone production in D. melanogaster fat-fed females. I synthesized the first synthetic (Z,Z)-7,11- C27 diene, and -C29 diene for J. M. Jallon at his request to confirm our finding of this long-sought pheromone system. It may be a bit hard to find in the older literature, but there was lot of controversy before my participation with Terry Davis, with others insisting that CVA was the only bioactive element. Any way, we were correct, justifying our efforts. I had a US Navy grant to study this same phenomenon in sand flies, but Hurricane David in Florida had destroyed our only known collection site, and no one had managed to colonize these sand flies. We thanked the Navy for "allowing" work to continue on the world's most popular insect, D. m., absent being able to work on our intended test subject.
There is another question, long not understood, about houseflies. I found the housefly sex pheromone (Science, 1971) using lab colony CradsonP females that were loaded with (Z)-9-tricosene, about the 4th sex pheromone discovered. However wild-caught females did not always have much of it, and some did not have any in their hydrocarbon profile regardless of age. But all males responded actively to it, and females aggregate to it. There are some branched alkanes in females that contribute to male stimulant bioactivity, but the reason why (Z)-9-tricosene is not always present in wild flies is undiscovered. Could it be that houseflies feeding on high fat levels are responsible? Molecular biology did not exist back in the day to tell us the genetic element. In any case, (Z)-9-tricosene is presently sold around the world (online!) as an adjuvant to various housefly baits, almost half a century after it first appeared in my GC profiles! Several commercial companies sell housefly bait, Zoecon, Bayer, Starbar.
50 years ago- at the beginning of this science, Cotton Boll Weevil pheromone was found to be useful in monitoring. gypsy Moth in the USA mass trapping. Japanese beetle traps with pheromone are sold in the USA.
Advances in the use of pheromones for stored-product protection by Pasquale Trematerra
September 2011
Journal of Pest Science 85(3)
DOI: 10.1007/s10340-011-0407-9
Abstract
Considerable progress has been made in the monitoring and control of stored-product pests, mainly Lepidoptera and Coleoptera, by pheromones, which are used in mass trapping, attracticide and mating disruption methods. In integrated pest management programmes of stored-product protection, the use of pheromones can lead to a reduction in chemical treatments, with economic advantages and the improvement of food-product quality. In this article, I report some promising results offering efficient detection and control of stored-product pests based on pheromones and line up a number of remaining questions to be answered to improve the reliability and competitiveness of the methods used.
If pest populations are low, usually the use of pheromones will be more useful for mass trapping. Of course, there are several factors affecting the efficiency of pheromone traps such as pest density, pheromone density, trap type and pheromone dose.
In Egypt, we used mass trapping with pheromones very effectively for capturing females of Spodoptera littoralis, Pectinophora gossypiella and Earias insulana and any other lepidopterous insects. You have to take care of the source you buy pheromone capsule from and the right time for use