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ŠUMARSKI LIST 7-8/2013 str. 41     <-- 41 -->        PDF

2.7 to 36.6 times lower). In the present study, the rapid efficiency shrinkage of all season dispenser was much more progressive (moving from 2.7 to 112.4 times lower). That is why ECOLURE MEGA should be considered as comparably less efficient type of all season dispenser then ECOLURE TUBUS.
Number of trapped beetles strongly depend on many environmental factors and local conditions, such as temperature, exposition, sun exposure and others (Lobinger, 1995). We highgly eliminated influence of these factors during the study by type of used statistic test. Furthermore, the position of all traps was exactly the same as used Nakládal and Sova (2010) in 2008. But all 20 traps lured by the standard dispenser (ECOLURE CLASSIC) by Nakládal and Sova (2010) in 2008 were lured by the all season dispenser (ECOLURE MEGA) in this experiment. And vice versa, all 20 traps lured by the all season dispenser (ECOLURE TUBUS) in 2008 were lured by the standard dispenser (ECOLURE CLASSIC) in this experiment. This methodology supported correctness of data interpretation of both studies and show that all season dispensers are much less effective then standard dispensers.
Low number of trapped beetles closely corresponds with lower pheromone released level to the environment (and it immediately after the season beginning). This fact relate with higher portion of males in trapped sample and others problems reviewed by Nakládal and Sova (2010).
Interesting is very low average portion of male (8 % only) for both of type of dispensers. Many authors discuss factors influenced male portion in catches. The sex ratio of beetles caught can vary according to the trap type (Bakke et al., 1983), different sex behavior during the tree colonization (Byers, 1983), pheromone mixture and its different release level of (4S)-cis-verbenol (Jakuš and Blaženec 2002). Portion of male may be influenced also by present males in environment. Although some authors indicate a percentage of I. typographus males after egg hatching of about 50 % (Merker and Wild 1954; Annila, 1969) and sex ratio of emerging beetles 1:1 (Botterweg, 1982), some study show population density depending sex ratio (Annila, 1971; Lobinger, 1996). Portion of captured males in pheromone traps usually vary about 35 %. Botterweg (1982) indicate 30.6 %, Zumr (1982) 39 %, Faccoli and Buffo (2004) 33.1 % respectively 37.7 % in two years experiment. Eight percent, recorded in this study, is extremely low value which is not possible to satisfactorily explain.
Conclusion
Zaključak
Efficiencies of standard (ECOLURE CLASSIC) and all season dispensers (ECOLURE MEGA) were compared. Both dispensers contains the same chemical components, on the other hand they have different packs. All season dispensers (ECOLURE MEGA) trapping less beetles in compare of ECOLURE CLASSIC immediately after their setting dispensers in the forest.
Statistical difference of number trapped beetles was non significant during only the first checking (only first 10 days) and then was highly significant (next 123 days).
Generally, ECOLURE all season dispensers trapping lower count of beetles in compare of classic dispenser (ECOLURE CLASSIC). ECOLURE all season dispenser may be usable in inaccessible terrains (etc.) where we assume checking period exceed 50 days. They are weakly effective 60 days after the setting on and practically non-effective later. The ECOLURE all season dispensers have from 36.6 to more over 100 times lower recorded efficiency in the end of declared efficiency in compare with ECOLURE CLASSIC.
Acknowledgements
Zahvala
This paper was written in the framework of the research project CIGA No. 20124310 (Czech University of Life Sciences Prague) "Prognostic model for identification of nun moth (Lymantria monacha /L./) outbreaks in expected climatic changes in the Czech Republic". We are also obliged to Jaroslav Sova (Svatonice, Czech Republic).