SEX-PHEROMONE TRAPS FOR MONITORING THE HONEYDEW MOTH, CRYPTOBLABES-GNIDIELLA - EFFECT OF PHEROMONE COMPONENTS, PHEROMONE DOSE, FIELD AGING OF DISPENSER, AND TYPE OF TRAP ON MALE CAPTURES

The effects of pheromone components, pheromone dose in the dispenser, aging of dispenser in the field, and trap type on trapping efficiency of males of the honeydew moth, Cryptoblabes gnidiella (Mill.) (Lepidop tera: Pyralidae), were investigated. At dosages of 2 or 0.2 mg, a bina ry blend containing (Z)-11-hexadecenal (Z11-16:Ald) and (Z)-13-octadec enal (Z13-18:Ald) (1:1) was as effective in attracting males as a quat ernary blend containing Z11-16:Ald, (E)-11-hexadecenal (E11-16:Ald), Z 13-18:Ald and (E)-13-octadecenal (E13-18:Ald), (10:1:10:1). Within the range of 20 to 2000 mug pheromone/dispenser, response of males increa sed positively with the pheromone dose; however, a load of 10 or 20 mg /dispenser was significantly less attractive to males than 2 mg/dispen ser. The effect of aging of the dispenser in the field on trapping eff iciency was significant. Captures in traps baited with 3- and 4-week-o ld septa were lower than those in traps baited with 1- or 2-week-old s epta. The gradual loss of attractancy exhibited by rubber septa indica tes that septa should be renewed within 2-3 weeks. The release rate of the pheromone was measured in a flow system and monitored with Z11-16 :Ald only. The emission was almost constant for 18 days and then decre ased gradually until the 34th day. The nonsticky IPS trap was as effec tive in capturing honeydew moth males as the sticky Pherocon IC trap. The possibility of using the nonsticky, nonsaturating and easy-to-hand le IPS traps may lead to better and easier monitoring of honeydew moth populations.