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Tomatoes 2008
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The insect's world is filled with many odors. Insects use these odors to cue them in a variety of complex social behaviors, including courtship, mating and egg laying. Scientists and pest control specialists have known about these complex communication systems for decades. Recently, this high technology has been made available for use by the average person because these chemicals, called pheromones (pronounced fair-a-mones), can be produced synthetically. Pheromones regulate many types of insect behavior. Sex pheromones are produced by one sex (usually the female) to attract the other sex for mating. Mass attacks by certain bark beetles are coordinated by aggregation pheromones that attract other beetles to the same tree. Alarm pheromones are produced by honey bees and aphids to help in colony defense. Trail pheromones are produced by ants to help other worker ants find food sources. Insect pheromones, particularly the sex pheromones of moths, are among the most biologically active compounds known. A single molecule of pheromone can be detected by some species. Because of this sensitivity, insect sex pheromones are now used in insect management. Synthetic sex pheromones are available for many pest insects, and are used for pest detection. More than 60 types of pheromone or other trap types are available from commercial sources listed at the end of this publication. Two commonly used trap types are the delta and wing traps.. Other trap designs exist (funnel traps, sticky cards, water pan traps, cone traps) and may improve the catch for some species. Pheromone traps are more convenient to use than other kinds of traps, such as blacklights, which are non-specific, cumbersome, and require batteries or access to electricity.
Pheromone traps allow the grower or homeowner to make a better decision about when to apply control measures. Because of this, they can form an integral part of an IPM (Integrated Pest Management) program. Also, pheromones have been used to detect the presence of exotic pests such as the gypsy moth, which has been detected in neighboring states. Pheromone uses recommended in New Mexico primarily involve sex pheromones produced by female moths. These traps only attract males of the same or closely related species and do not increase the level of pest infestation around a trap site. More general attractants such as food lures or aggregation pheromones can increase insect activity in the vicinity of a trap. The primary uses of pheromones in New Mexico are to help determine:
FRUITGeneral recommendations for pheromone trap use in fruit orchards are as follows:
Recommended density:
Checking and servicing traps count and remove the insects at least once a week, preferably 3 to 7 times a week during periods when the pests are most likely to be flying in the greatest numbers. Record the number of pests caught and the date the trap was checked in order to find out how many pests were present per day. Replace pheromone dispensers (synthetic pheromone source) every 2-4 weeks to make sure a constant level of pheromone is being released. Replace sticky cardboard bottoms of traps every 200-300 pests collected, or as the sticky surface becomes dirty. Keep a record of dates and types of trap service to assure proper trap function. The objective is to keep about the same degree of stickiness in the trap throughout the trapping season, and to keep track of expenses. 5) Dispenser storage and removal ï keep dispensers in the freezer until needed for use. Do not leave used septa or dispenser containers (wrappers) in the orchard or garden. 6) Trapping multiple pests ï place each trap type in a separate tree; ie. don't put peach tree borer and oriental fruit moth pheromone traps in the same tree. Best if the trees are at least 30 feet apart. Recommendations for specific fruit insect pests are as follows: Codling Moth ï Captures of the first male moth can be used to estimate closely the occurrence of egg laying when degree day models are used. For example, in the north central fruit-growing areas, first insecticide applications are tentatively recommended 270-420 degree days (base temperature of 50 F) after the first male is caught in the pheromone trap. The degree day concept is still being studied; therefore, as a general rule, control measures for codling moth should be implemented 3 to 4 weeks after the first male is caught, if populations exceed two moths per trap per week for 2 consecutive weeks. Specific recommendations for pheromone trap use in monitoring codling moth populations are given in Table 1. Peach Tree Borer ï Treatments are recommended 7 to 10 days after the first moth is captured, and at monthly intervals as long as traps continue to capture at least five moths per week. An alternative fall application may also be used. Contract your county extension agent for details. Leafrollers (Fruit Tree, Omnivorous, Three Lined) ï Treatments should be timed approximately 7 to 10 days after the first moth captures. Peach Twig Borer ï Detection of the first generation flight indicates the time to treat apricots. The second-generation flight indicates timing to protect peach trees. Treatments should be made 8 to 10 days after these flights begin. Western Cherry Fruit Fly ï Treatments are recommended 7 to 10 days after the first flies are captured in the spring, usually several weeks after petal fall. Table 1. Recommendations for Pheromone Trap use for Codling Moth in Monitoring and Control Applications. (a) ________________________________________________________________________________________ Trap unit Timing of Determination of Evaluation of Mass and operation control population levels mating trapping measures disruption _________________________________________________________________________________________ Trap design Pherocon 1 CP (c) Same Same Same Pheromone dispenser Pherocon rubber Same Same Same stopper (c) Maintenance schedule (b) Trap renewal Every 4 wks or after Same Same Same cum. catch of 70 moths Pheromone dispenser Every 6 wks Same Same renewal Removal of catch 2 times/wk Once/wk 2 times/wk Once/wk Trap placement Before spring emer- Same Same Same (temporal) gence until end of flight Trap placement (within tree): Elevation 1/3 up of vertical Same in upper 1/3 in upper 1/3 canopy dimension of canopy of canopy Quadrant Southeast at Same Same Same periphery of canopy Trap placement (within orchard): Center traps Evenly spaced Uniform grid Same Same throughout orchard pattern Border traps If influx Same Same suspected Trap density Minimum of 3 At least 1/ha At least 1/ha Optimal trap in small; 1/5 density ha in large not known orchards ______________________________________________________________________________________________ (a) From Western Regional Research Group. 1986. WRRPO12 (University of California Bulletin 1918): p. 17. (b) Or Pherocon 1 CP trap and Pherocon rubber septum: will vary with other trap units. (c) Or other trap unit if comparative data available; Pherocon is a registered trademark. SHADE TREESLilac/Ash Borers and Carpenterworms ï Treatments should be applied 7 to 10 days after the first moth is captured. If strong flights continue (five or more/week), reapplications are suggested at monthly intervals. Nantucket Pine Tip Moth ï Begin monitoring at least by mid-April to determine when peak moth flights occur. Control measures should be applied 5 to 10 days after each peak flight. Up to five flights can occur each year, depending upon location in the state. Only two flights occurred in the Albuquerque area in 1988, with sprays being recommended on May 5-15 and July 7-17. These dates must be determined each year for maximum effectiveness of the treatments. Bark Beetle ï Experimental applications of bark beetle aggregation pheromones for control are in progress. Most trials involve attracting beetles to trap trees that will be treated with insecticide or logged. Bark beetle pheromones are not recommended for homeowner pest control. VEGETABLESCorn Earworm ï Detection of moths indicate the time to spray sweet corn. If moths continue to be trapped, treatments should continue. STORED PRODUCTSIndian Meal Moth, Lesser Grain Borer, Red and Confused Flour Beetles, Sawtooth and Merchant Grain Beetles ï Pheromones are used for these species to detect an infestation and when insecticide treatment is needed. NUISANCE PESTSWasps, Yellow Jackets, Bees and House Flies ï Traps will help reduce population levels around houses and parks. GREENHOUSESWhiteflies and Aphids ï Yellow sticky traps are used to help reduce populations and monitor population levels for timing chemical controls.
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