Behavioral responses of the Asian larch bark beetle, lps subelongatus Motsch. to three potential aggregation pheromone components, ipsenol （racemic or [-]- enantiomer）, ipsdienol （racemic or [＋]-enantiomer） and 3...Behavioral responses of the Asian larch bark beetle, lps subelongatus Motsch. to three potential aggregation pheromone components, ipsenol （racemic or [-]- enantiomer）, ipsdienol （racemic or [＋]-enantiomer） and 3-methyl-3-buten- l-ol, were tested using partial or full factorial experimental designs in two provinces （Inner Mongolia and Jilin） of northeastern China. Our field bioassays in Inner Mongolia （Larix principis- rupprechtii Mayr. plantation） clearly showed that ipsenol, either racemic or 97%-（-）- enantiomer, was the only compound that significantly attracted both sexes of 1. subelongatus, while all other compounds （singly or in combinations） were unattractive. There were no two- or three-way synergistic interactions. However, in Jilin Province （L. gmelini [Rupr.] Rupr. Plantation）, all the individual compounds tested were inactive, except a very weak activity by 97%-（-）-ipsenol in 2004 when the beetle population was very high. While a combination of ipsenol and ipsdienol （racemates or enantiomerically pure natural enantiomers） showed a significant attraction for both sexes of I. subelongatus, indicat- ing a two-way synergistic interaction between these two major components, addition of 3-methyl-3-buten-l-ol to these active binary blend（s） did not have any effects on trap catches, suggesting that ipsenol and ipsdienol are the synergistic aggregation pheromone components of I. subelongatus in Jilin Province. It seems that 97%-（-）-ipsenol in Inner Mongolia or the binary blend of 97%-（-）-ipsenol and 97%-（＋）-ipsdienol in Jilin Province are superior to their corresponding racemates, which might be due either to weak inhibitory effects of the antipode enantiomers or to reduced release rates of the active natural enan- tiomer（s） in the racemate（s）. Our current bioassay results suggest that there is a strong geographical variation in aggregation pheromone response of L subelongatus in northeastern China. Future research on the pheromone production and response of 1. subelongatus from different regions in Northeast Asia will surely improve our understanding of the dynamic aggregation pheromone system of this economically important forest pest insect.展开更多
The Asian larch bark beetle, Ips subelongatus, is considered to be the major pest of larch within its natural range. We investigated the electrophysiological and behavioral characteristics as well as mitochondrial DNA...The Asian larch bark beetle, Ips subelongatus, is considered to be the major pest of larch within its natural range. We investigated the electrophysiological and behavioral characteristics as well as mitochondrial DNA cytochrome oxidase subunit I sequences of L subelongatus from 13 geographic populations throughout northeastern China in order to explore population divergence of aggregation pheromone responses and the extent of potential genetic divergence. Electrophysiological analyses showed that antennae of I. sube-longatus from all the six tested populations responded strongly to （S）-（-）-ipsenol （100% detection; 0.35-0.73 mV） in gas chromatography （GC）-electroantennographic detection （EAD） analyses, while its antipode, （R）-（＋）-ipsenol was antennally inactive. I. subelon- gatus populations varied in their responses to （R）-（-）- and （S）-（＋）-ipsdienol in GC-EAD analyses. Behavioral bioassays demonstrated that （S）-（-）-ipsenol alone was significantly attractive at all the tested sites, supporting its status as a key pheromone component of L subelongatus, whereas （S）-（＋）-ipsdienol was inactive alone. Adding （S）-（＋）-ipsdienol to （S）-（-）-ipsenol did not have any effect on the trap catches from some populations in Inner Mongolia. However, （S）-（＋）-ipsdienol showed a strong synergistic effect on （S）-（-）- ipsenol from several populations in Jilin and Liaoning Provinces, and a weak synergistic effect from some transition populations in Heilongjiang Province. Furthermore, 27 mito- chondrial haplotypes were found among the 13 populations （intraspecific nucleotide di- vergence, 0.1%-1.1%）. Analyses of molecular variance and haplotype networks indicated that different geographic populations have developed some genetic variation but did not form completely independent groups. From an applied point of view, a universal synthetic binary blend ofracemic ipsenol and （S）-（＋）-ipsdienol might have a potential for monitoring or even mass-trapping of I. subelongatus across northeastern China, even though some populations only use （S）-（-）-ipsenol alone as their active pheromone component.展开更多
Ips subelongatus Motschulsky were raised indoors and in the field using fresh baits for Study of biological and ecological characteristics during 1992-1994. The life cycle of the pest in Lishu County Jilin Province wa...Ips subelongatus Motschulsky were raised indoors and in the field using fresh baits for Study of biological and ecological characteristics during 1992-1994. The life cycle of the pest in Lishu County Jilin Province was described. The study results indicated that temperature was a main factor affecting the development of 1ps Subelongatus, The initial temperature for development of egg, larva, pupa and adult was 6.1, 8.0, 10.3 and 9.8℃,respectively. To complete one-generation needs, respectively, 48 d at temperature of 18 ℃, 39 d at 20℃ and 33d at 22℃. The pest has different number of generations in different area as a result of temperature change. In Jilin Province, it generally has three generations, except that some individuals have 2 generations. The nature enemies for this pest are Thanasinus substriatus, Tomhoicobia seitneri Ruschk, Coeliodes sp. etc.展开更多
文摘Behavioral responses of the Asian larch bark beetle, lps subelongatus Motsch. to three potential aggregation pheromone components, ipsenol （racemic or [-]- enantiomer）, ipsdienol （racemic or [＋]-enantiomer） and 3-methyl-3-buten- l-ol, were tested using partial or full factorial experimental designs in two provinces （Inner Mongolia and Jilin） of northeastern China. Our field bioassays in Inner Mongolia （Larix principis- rupprechtii Mayr. plantation） clearly showed that ipsenol, either racemic or 97%-（-）- enantiomer, was the only compound that significantly attracted both sexes of 1. subelongatus, while all other compounds （singly or in combinations） were unattractive. There were no two- or three-way synergistic interactions. However, in Jilin Province （L. gmelini [Rupr.] Rupr. Plantation）, all the individual compounds tested were inactive, except a very weak activity by 97%-（-）-ipsenol in 2004 when the beetle population was very high. While a combination of ipsenol and ipsdienol （racemates or enantiomerically pure natural enantiomers） showed a significant attraction for both sexes of I. subelongatus, indicat- ing a two-way synergistic interaction between these two major components, addition of 3-methyl-3-buten-l-ol to these active binary blend（s） did not have any effects on trap catches, suggesting that ipsenol and ipsdienol are the synergistic aggregation pheromone components of I. subelongatus in Jilin Province. It seems that 97%-（-）-ipsenol in Inner Mongolia or the binary blend of 97%-（-）-ipsenol and 97%-（＋）-ipsdienol in Jilin Province are superior to their corresponding racemates, which might be due either to weak inhibitory effects of the antipode enantiomers or to reduced release rates of the active natural enan- tiomer（s） in the racemate（s）. Our current bioassay results suggest that there is a strong geographical variation in aggregation pheromone response of L subelongatus in northeastern China. Future research on the pheromone production and response of 1. subelongatus from different regions in Northeast Asia will surely improve our understanding of the dynamic aggregation pheromone system of this economically important forest pest insect.
文摘The Asian larch bark beetle, Ips subelongatus, is considered to be the major pest of larch within its natural range. We investigated the electrophysiological and behavioral characteristics as well as mitochondrial DNA cytochrome oxidase subunit I sequences of L subelongatus from 13 geographic populations throughout northeastern China in order to explore population divergence of aggregation pheromone responses and the extent of potential genetic divergence. Electrophysiological analyses showed that antennae of I. sube-longatus from all the six tested populations responded strongly to （S）-（-）-ipsenol （100% detection; 0.35-0.73 mV） in gas chromatography （GC）-electroantennographic detection （EAD） analyses, while its antipode, （R）-（＋）-ipsenol was antennally inactive. I. subelon- gatus populations varied in their responses to （R）-（-）- and （S）-（＋）-ipsdienol in GC-EAD analyses. Behavioral bioassays demonstrated that （S）-（-）-ipsenol alone was significantly attractive at all the tested sites, supporting its status as a key pheromone component of L subelongatus, whereas （S）-（＋）-ipsdienol was inactive alone. Adding （S）-（＋）-ipsdienol to （S）-（-）-ipsenol did not have any effect on the trap catches from some populations in Inner Mongolia. However, （S）-（＋）-ipsdienol showed a strong synergistic effect on （S）-（-）- ipsenol from several populations in Jilin and Liaoning Provinces, and a weak synergistic effect from some transition populations in Heilongjiang Province. Furthermore, 27 mito- chondrial haplotypes were found among the 13 populations （intraspecific nucleotide di- vergence, 0.1%-1.1%）. Analyses of molecular variance and haplotype networks indicated that different geographic populations have developed some genetic variation but did not form completely independent groups. From an applied point of view, a universal synthetic binary blend ofracemic ipsenol and （S）-（＋）-ipsdienol might have a potential for monitoring or even mass-trapping of I. subelongatus across northeastern China, even though some populations only use （S）-（-）-ipsenol alone as their active pheromone component.
文摘Ips subelongatus Motschulsky were raised indoors and in the field using fresh baits for Study of biological and ecological characteristics during 1992-1994. The life cycle of the pest in Lishu County Jilin Province was described. The study results indicated that temperature was a main factor affecting the development of 1ps Subelongatus, The initial temperature for development of egg, larva, pupa and adult was 6.1, 8.0, 10.3 and 9.8℃,respectively. To complete one-generation needs, respectively, 48 d at temperature of 18 ℃, 39 d at 20℃ and 33d at 22℃. The pest has different number of generations in different area as a result of temperature change. In Jilin Province, it generally has three generations, except that some individuals have 2 generations. The nature enemies for this pest are Thanasinus substriatus, Tomhoicobia seitneri Ruschk, Coeliodes sp. etc.
