The Identification of the Pheromones of Harmful Pyralids to the Pomegranate and the Other Fruit Trees in Iran and the Investigation on the Effect of Host-Plant on Their Pheromone Composition

To clarify the systematical identification of the pyralid pest known as E. bigella the samples feeding on quince, pomegranate, fig and orange trees were collected from Esfahan, Fars, Yazd, Mazandaran, Ghom and South Khorasan provinces. The female genitalia of the samples collected on quince fruit or quince bark (Natanz, Esfahan province) were similar to E. bigella as described by Roesler (1973) but the male genitalia of the same sample were different from E. bigella or all other described species. It suggests that these samples may belong to a new subspecies of E. bigella. The differences between the genitalia of these samples (E. bigella nsp.) and E. bigella are discussed. E. bigella nsp. was also identified on pomegranate fruits (Esfahan province) and on quince in other regions (Yazd and South Khorasan). Ectomyelois ceratoniae was identified on the fruits of pomogrante (Esfahan, Fars, Yazd, Qom and Mazandaran), fig (Yazd) and for the first time on quince and orange (Mazandaran). E. bigella nsp. And E. ceratoniae cohabited on pomegranate fruits in Esfahan province. Euzopherodes vapidella f. tenebrosa was identified on the pomegranate bark in Yazd. The results showed that E. bigella nsp. feeds on fruits and also the bark but E. ceratoniae and the Euzopherodes vaoidella f. tenebrosa were only collected on fruits and on the bark respectively. Two simultaneous field trapping experiments were conducted in two adjacent orchards of pomegranate and fig in Yazd in August 2008 to study the effect of host plants on the pheromone-based communication of carob moth. The captures of traps baited with live virgin females originated from: 1) pomegranate ; 2) fig ; 3) laboratory reared on artificial diet were compared with synthetic pheromone in both orchards. The results in the pomegranate orchard showed that the capture of traps baited with females originated from pomegranate (20 3 males per trap and per d) was significantly more than traps baited with females originated from fig (5.6 0.7 males per trap and per d) or with reared females on diet (5.4 2.1 males per trap and per d). In the fig orchard, there was not any significant difference between the captures of traps baited with females originated from pomegranate (9.9 3.3 males per trap and per day) and baited with females originated from fig (10.3 5.6 males per trap and per day). But the captures of traps baited with females originated from pomegranate in the pomegranate orchard and of traps baited with females originated from fig in the fig orchard were respectively two times more than their captures in fig and in pomegranate orchards. The capture of traps baited with reared females on diet were almost similar in pomegranate and fig (6.5 1.4 males per trap and per d) orchards. These results evidenced that the host plants modulate the pheromone-based communication of carob moth and the pheromone components of the populations of this insect on different host plants are probably different. Based on GC-MS the female specific volatiles of individuals reared on semi-artifitial diet were different with ones extracted from individuals reared on pomegranate fruit. The results evidenced the role of host plant on the female specific volatile components of carob moth.