2. Vit6, J.P., Renwick, J.A.A.: J. Insect Physiol. 17, 1699 (1971) 3. Mori, K.: Tetrahedron Letters 26, 2187 (1975); Tetrahedron (in press) 4. Vit~, J.P., Pitman, G.B. : Canad. Entomol. 101, 113 (1969) 5. Silverstein, R.M., et al. : Science 154, 509 (1966) 6. Birch, NI.C., Wood, D.L. : J. Chem. Ecol. 1, 101 (1975)
Southern Pine Beetle: Effect of Aerial Pheromone Saturation on Orientation
45g/ha 100-
n=98
450g/ha
1 n=137
n=237
n=407
J
n=695
n=979
B
I
A
5o[
J.P. Vit6 Forstzoologisches Institut der UniversitS& Freiburg i. Br. P.R. Hughes and J.A.A. Renwick
*Y
el.
Boyce Thompson Institute for Plant Research, Yonkers, N.Y. 10701 Aggregation of the southern pine beetle, Dendroctonus frontalis Zimm. (Coleoptera: Scolytidae) on loblolly pine (Pinus taeda L.) under beetle attack was not disrupted by aerial applications of "Frontalure", a mixture of the attractant pheromone frontalin and the host terpene c~-pinene. Instead, aerial saturation with the pheromone in a heavily beetleinfested pine forest resulted in a rapid increase in the aggregation of beetles on pine trees undergoing attack. Previous work has shown that some disorientation of endemic populations can be effected by attracting the beetles to a source or numerous competing sources of synthetic attractants, particularly in the absence of naturally attacked trees. The experiments reported here were designed to determine whether the theory of "disorientation" or "communication disruption" [1] might be applicable to keep epidemic D. frontalis populations from aggregating on host trees that were under natural attack. 230 kg of rice seed soaked with Frontalure [2] were applied by aircraft equipped with a rice spreader over a 10 ha section of pine forest including an actual D. frontalis infestation of ~ 1.6 ha. The test area, marked by balloons, was evenly seeded with rice which penetrated the canopy well, releasing approximately 86% of the Frontalure during the first 3 h, and 96% within 24 h. One hardware cloth sticky trap 30 x 30 cm was placed on each of five naturally attractive pine trees under attack by the beetles and on each of five non-host (broadleaf) trees. The latter were baited with two plastic caps containing enough Frontalure to release racemic frontalin (99%) at an estimated rate of 2 mg/h and trap. Aerial applications of Frontalure-soaked rice were made in the early afternoon before the daily peak of beetle flight occurred. Beetles caught on the traps were removed at noon each day before and after aerial treatments. A preliminary application of Frontalure amounting to 45 g frontalin per ha clearly reversed the pattern of beetle catches. The majority of beetles was caught on the baited traps before the aerial application, but on the unbaited traps afterward; However, suppression of beetle response to the Frontalurebaited traps was not complete, probably due to insufficient pheromone saturation of the area throughout the test period. A second aerial application of Frontalure-soaked rice representing 450 g frontalin per ha almost completely interrupted the beetle response to the Frontalure-baited traps on the broadleaf trees. This treatment resulted in heavily increased beetle catches on the pine trees that were undergoing attack. During the 24-h period prior to the application, both sets 44
Auc ust
12 13
12 14
12 15
12 16
12 17
12 18
Fig. 1. Percent (n=total) response of D. frontalis to 5 sticky traps (A) on oak trees baited with Frontalure and (B) on pine trees under attack by the beetle before and after Frontalure application (arrows) at a rate of 45 and 450 g synthetic frontalin (racemic mixture) per ha. Sour Lake, Texas, August 1974 of traps were comparable in the numbers and sex ratios of beetles caught (Fig. 1)_ The results corroborate the effectiveness of frontalin-base lures in concentrating D. frontalis populations but indicate that aerial saturation with the aggregation pheromone,-perhaps in contrast to the sex pheromones of lepidoptera-cannot disrupt the process by which this bark beetle colonizes host trees. Supported, in part, by the State of Texas through the Texas Forest Service. Received November 3, 1975 1. Shorey, H.H., in: Control of Insect Behavior by Natural Products, p. 249 (D.L. Wood, R.M. Silverstein, M. Nakajima, eds.). New York: Academic Press 1970 2. Vit6, J.P. : Contrib. Boyce Thompson Inst. 24, 343 (1970)
Lysimachia: ( ) l b l u m e n der
Holarktis
Stefan Vogel Institut fiir Systematische Botanik und Pflanzengeographie der F.U. Berlin Erst seit kurzem ist bekannt, dab eine gr6Bere Zahl tierblfitiger Pflanzensippen statt der herk6mmlichen Lockmittel, Nektar und Pollen, in besonderen Organen (Elaiophoren) fettes Ibl darbietet [6]. Das Vorkommen der neuen Blumenklasse schien auf Sfidamerika und das Kapland beschrS.nkt; als (blausbeuter wurden bisher nur einige neotropische Bienenfamilien ermittelt. Weitere Nachweise zeigen jetzt, dab dieses Anlockungsprinzip auch in der Holarktis auftritt: Die ftir Europa, Asien und Nordamerika beschriebene [1, 4, 5], unerkl/irte bzw. miBdeutete obligate Bindung der Schenkelbienen (Macropis, Fam. Melittidae) an Lysimachia-Arten (Primulac.) beruht gleichfalls auf dem Angebot von Blumen61. Gilbweiderich (L. vulgaris) und Pfennigkraut (L. nummularia) galten Naturwissenschaften 63 (1976)
9 by Springer-Verlag 1976
Southern Pine Beetle: Effect of Aerial Pheromone Saturation on Orientation
45g/ha 100-
n=98
450g/ha
1 n=137
n=237
n=407
J
n=695
n=979
B
I
A
5o[
J.P. Vit6 Forstzoologisches Institut der UniversitS& Freiburg i. Br. P.R. Hughes and J.A.A. Renwick
*Y
el.
Boyce Thompson Institute for Plant Research, Yonkers, N.Y. 10701 Aggregation of the southern pine beetle, Dendroctonus frontalis Zimm. (Coleoptera: Scolytidae) on loblolly pine (Pinus taeda L.) under beetle attack was not disrupted by aerial applications of "Frontalure", a mixture of the attractant pheromone frontalin and the host terpene c~-pinene. Instead, aerial saturation with the pheromone in a heavily beetleinfested pine forest resulted in a rapid increase in the aggregation of beetles on pine trees undergoing attack. Previous work has shown that some disorientation of endemic populations can be effected by attracting the beetles to a source or numerous competing sources of synthetic attractants, particularly in the absence of naturally attacked trees. The experiments reported here were designed to determine whether the theory of "disorientation" or "communication disruption" [1] might be applicable to keep epidemic D. frontalis populations from aggregating on host trees that were under natural attack. 230 kg of rice seed soaked with Frontalure [2] were applied by aircraft equipped with a rice spreader over a 10 ha section of pine forest including an actual D. frontalis infestation of ~ 1.6 ha. The test area, marked by balloons, was evenly seeded with rice which penetrated the canopy well, releasing approximately 86% of the Frontalure during the first 3 h, and 96% within 24 h. One hardware cloth sticky trap 30 x 30 cm was placed on each of five naturally attractive pine trees under attack by the beetles and on each of five non-host (broadleaf) trees. The latter were baited with two plastic caps containing enough Frontalure to release racemic frontalin (99%) at an estimated rate of 2 mg/h and trap. Aerial applications of Frontalure-soaked rice were made in the early afternoon before the daily peak of beetle flight occurred. Beetles caught on the traps were removed at noon each day before and after aerial treatments. A preliminary application of Frontalure amounting to 45 g frontalin per ha clearly reversed the pattern of beetle catches. The majority of beetles was caught on the baited traps before the aerial application, but on the unbaited traps afterward; However, suppression of beetle response to the Frontalurebaited traps was not complete, probably due to insufficient pheromone saturation of the area throughout the test period. A second aerial application of Frontalure-soaked rice representing 450 g frontalin per ha almost completely interrupted the beetle response to the Frontalure-baited traps on the broadleaf trees. This treatment resulted in heavily increased beetle catches on the pine trees that were undergoing attack. During the 24-h period prior to the application, both sets 44
Auc ust
12 13
12 14
12 15
12 16
12 17
12 18
Fig. 1. Percent (n=total) response of D. frontalis to 5 sticky traps (A) on oak trees baited with Frontalure and (B) on pine trees under attack by the beetle before and after Frontalure application (arrows) at a rate of 45 and 450 g synthetic frontalin (racemic mixture) per ha. Sour Lake, Texas, August 1974 of traps were comparable in the numbers and sex ratios of beetles caught (Fig. 1)_ The results corroborate the effectiveness of frontalin-base lures in concentrating D. frontalis populations but indicate that aerial saturation with the aggregation pheromone,-perhaps in contrast to the sex pheromones of lepidoptera-cannot disrupt the process by which this bark beetle colonizes host trees. Supported, in part, by the State of Texas through the Texas Forest Service. Received November 3, 1975 1. Shorey, H.H., in: Control of Insect Behavior by Natural Products, p. 249 (D.L. Wood, R.M. Silverstein, M. Nakajima, eds.). New York: Academic Press 1970 2. Vit6, J.P. : Contrib. Boyce Thompson Inst. 24, 343 (1970)
Lysimachia: ( ) l b l u m e n der
Holarktis
Stefan Vogel Institut fiir Systematische Botanik und Pflanzengeographie der F.U. Berlin Erst seit kurzem ist bekannt, dab eine gr6Bere Zahl tierblfitiger Pflanzensippen statt der herk6mmlichen Lockmittel, Nektar und Pollen, in besonderen Organen (Elaiophoren) fettes Ibl darbietet [6]. Das Vorkommen der neuen Blumenklasse schien auf Sfidamerika und das Kapland beschrS.nkt; als (blausbeuter wurden bisher nur einige neotropische Bienenfamilien ermittelt. Weitere Nachweise zeigen jetzt, dab dieses Anlockungsprinzip auch in der Holarktis auftritt: Die ftir Europa, Asien und Nordamerika beschriebene [1, 4, 5], unerkl/irte bzw. miBdeutete obligate Bindung der Schenkelbienen (Macropis, Fam. Melittidae) an Lysimachia-Arten (Primulac.) beruht gleichfalls auf dem Angebot von Blumen61. Gilbweiderich (L. vulgaris) und Pfennigkraut (L. nummularia) galten Naturwissenschaften 63 (1976)
9 by Springer-Verlag 1976
