Pheromone study on acarid mites IV : Citral : composition and function as an alarm pheromone and its secretory gland in four species of acarid mites

Abstract

Through bioassay and biolegical investigations on the alarm pheromone of five species of acarid mites, Alettroglyphzts ovattes, CZirpoglt!phus lactis, Lardbglyphus konoi and Dermatophagoides forinae. following results were obtained. Citral and nery1 formate were more er less active as an alarm pheromone and not strictly species-specific within five species. Along with T. Putrescentiae, two more acarid mites, C lactis and L. konoi, were concluded to possess the alarm pheromone and citral was identified as their pheromone. Citral was emitted to the environment and the quantity of this discharge was 10 to 50 times larger when mites were disturbed than when undisturbed. Furthermore the composition of citral differed significantly between the disturbed (74-86% of neral) and undisturbed conditions (54-66% of neral), that is, the percentage of neral increased when disturbed. The original composition of extracted citral under 1-min soaking consisted of more than 90% of neral in the three species except L. konoi (75% of neral). Therefore the initial composition of citral when discharged from glands is supposed to consist of more than 90% of neral in three species, L. konoi, A. owatus and D. fLirinae. Secretory gland of citral was identified as the latero-abdominal gland or the oil gland in all species of mites.

Chemical ecology of astigmatid mites LXIX. Neryl formate [3,7-dimethyl-(Z)-2,6-octadienyl formate] as the alarm pheromone of an acarid mite, Histiogaster rotundus Woodring (Acari: Acaridae)

“…We have defined the alarm pheromone as follows; the escaping behavior is evoked with a disturbance by patting with a soft drawing brush or squashing one or several mites, and the same observation is reproducible on exposure of the mite volatile (Kuwahara et al, 1980b).…”

Chemical Ecology of Astigmatid Mites LXVII. Neral [3,7-dimethyl-(Z)-2,6-octadienal]: The Female Sex Pheromone of an Acarid mite, Histiogaster sp. (Acari: Acaridae).

“…Five species use the compound as their alarm pheromone: Carpoglyphus lactis, Lardoglyphus konoi (Kuwahara et al, 1980b), Suidasia medanensis (Leal et al, 1989d), Glycyphagus domesticus (Kuwahara et al, 1991), Schwiebea elongata . However, this is the first example identifying the function of neral as the female sex pheromone.…”

Chemical Ecology of Astigmatid Mites LXXIII. Neral as an Alarm Pheromone of the Acarid Mite, Oulenzia sp. (Astigmata: Winterschmidtiidae)

“…Other than alarm pheromones, sex and aggregation pheromones are also present as the same gland components of Astigmata (Kuwahara et al, 1980;Mizoguchi et al, 2003), and it is reasonable to understand that each species can handle a kind of pheromone function within the three. Recently, it has been realized that a species of mites can manipulate at least two kinds of pheromones (Kuwahara, 2001), such as found in Rhizoglyphus robini where a combination of the alarm and sex pheromones (neryl formate and α-acaridial, respectively) present in the same gland is manipulated to show each own function (Mizoguchi et al, 2003), and as found in Schwiebea elongata where neral functions not only as an alarm pheromone at a high dose but also as an attractant at a low dose, possibly an aggregation pheromone (Nishimura et al, 2002).…”

“…Chemical structures of the pheromones so far known are classified into three groups; 1) monoterpenes, 2) aromatics and 3) hydrocarbons (Kuwahara, 1999). The monoterpenes consist of five compounds; neryl formate in six species [four species belong to the genus Rhizoglyphus (Akiyama et al, 1997), Tyroborus lini (Tomita et al, 2003), and Tyrophagus putrescentiae (Kuwahara et al, 1975)], neral in five species [Carpoglyphus lactis (Kuwahara and Suzuki, 1983), Glycyphagus domesticus (Kuwahara et al, 1991a), Suidasia medanensis , Lardoglyphus konoi (Kuwahara et al, 1980) and Schwiebaea elongata ], geranial in Histiostoma laboratorium (Kuwahara et al, 1991b), isopiperitenone in Tyrophagus similis (Kuwahara et al, 1987) and β-acaridial in Tyrophagus longior (Noguchi et al, 1998). The aromatic compound 2-hydroxy-6-methylbenzaldehyde functions as the pheromone in Tyrophagus perniciosus (Leal et al, 1988).…”

“…Active components of these pheromones are secreted from a pair of opisthonotal glands present in each species (Kuwahara et al, 1979 and1980;Mizoguchi et al, 2003). Chemical structures of the pheromones so far known are classified into three groups; 1) monoterpenes, 2) aromatics and 3) hydrocarbons (Kuwahara, 1999).…”