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Developmental Duration (developmental + duration)
Selected AbstractsPhenological model of pear psylla Cacopsylla pyriENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2 2005L. Schaub Abstract A phenological model of first- and second-generation pear psylla, Cacopsylla pyri L. (Homoptera: Psyllidae), was developed. The model included a time-distributed delay and was based on authors' observations and literature data of termination of reproductive diapause, oviposition-period length, and developmental duration of juvenile stages depending on temperature. After calibrating microclimate, the model provided a good simulation of observations from different orchards in Switzerland and Italy over several years. The model or simulated output tables can be used to improve timing of monitoring and control measures. [source] Susceptibility of immature stages of Chrysoperla rufilabris (Neurop., Chrysopidae) to pyriproxyfen, a juvenile hormone analogJOURNAL OF APPLIED ENTOMOLOGY, Issue 2-3 2002T.-Y. Chen Effects of pyriproxyfen (Knack), a juvenile analog, at three concentrations (10, 50 and100 mg [AI]/l), on survival and development of all immature stages of Chrysoperla rufilabris (Burmeister), were determined in the laboratory. Pyriproxyfen significantly reduced the survival rates when eggs, first and third instars were treated, but not when the second instars and pupae were treated. When eggs were treated, the two higher concentrations reduced the eggs viability by 33.3,50%, and only 0.0,6.7% developed to adults. The lowest concentration of pyriproxyfen (10 mg [AI]/l) caused high mortality on third instars, not on other stages, indicating the third instar was the most vulnerable stage. Pyriproxyfen had significant effects on development for all immature C. rufilabris that successfully developed to adults with variations among the developmental stages and concentrations. The overall developmental duration from eggs to adults when eggs, first, and third instars were treated were 2.6,4.2, 2.4,4.1 respectively, and 6.0,7.1 d longer than those in water control, respectively. However, the overall developmental durations from eggs to adults were 0.5,1.2 d shorter than in water control when the second instars were treated with pyriproxyfen. The compatibility of pyriproxyfen with natural enemies in integrated pest management programs is discussed. [source] Performance of the potentially invasive Siberian moth Dendrolimus superans sibiricus on coniferous species in EuropeAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 3 2009Natalia I. Kirichenko Abstract 1,The native range of the Siberian moth extends from the Pacific Ocean (Russian Far East, Japan and Northern Korea) across Siberia, Northern China and Mongolia to the Ural Mountains. At the beginning of the 21st Century, this species was documented west of the Ural Mountains in the Republic of Mari El, indicating range extension toward the west. 2,The Siberian moth has recently been suggested for regulation as a quarantine pest for European and Mediterranean Plant Protection Organization member countries. However, no specific report on European host plants for this pest has been published so far. 3,In the present study, larval host plant choice and performance was tested for the first time on coniferous tree species that are widely distributed and of commercial value in Europe. 4,Based on dual-choice tests on neonates and mortality, developmental duration and relative growth rates of the first- to sixth-instar larvae, we found European larch Larix decidua to be the most suitable host for the moth larvae, whereas European black pine Pinus nigra and Scots pine Pinus sylvestris were the poorest hosts. The remaining conifer species tested, European silver fir Abies alba, Nordmann fir Abies nordmanniana, and Norway spruce Picea abies, were intermediate host plants. Douglas-fir Pseudotsuga menziesii, originating from North America, was chosen by the larvae to the same extend as European larch, and was also highly suitable for larval development. 5,If the moth is introduced to European countries, it will become damaging in stands of European larch and Douglas-fir, mixed stands of fir and spruce; however, it will be less damaging in forests dominated by two-needle pines. 6,We predict that Dendrolimus superans sibiricus will be able to survive and develop on the main European coniferous tree species, including non-native coniferous tree species, resulting in severe damage to large areas of forests. [source] Susceptibility of immature stages of Chrysoperla rufilabris (Neurop., Chrysopidae) to pyriproxyfen, a juvenile hormone analogJOURNAL OF APPLIED ENTOMOLOGY, Issue 2-3 2002T.-Y. Chen Effects of pyriproxyfen (Knack), a juvenile analog, at three concentrations (10, 50 and100 mg [AI]/l), on survival and development of all immature stages of Chrysoperla rufilabris (Burmeister), were determined in the laboratory. Pyriproxyfen significantly reduced the survival rates when eggs, first and third instars were treated, but not when the second instars and pupae were treated. When eggs were treated, the two higher concentrations reduced the eggs viability by 33.3,50%, and only 0.0,6.7% developed to adults. The lowest concentration of pyriproxyfen (10 mg [AI]/l) caused high mortality on third instars, not on other stages, indicating the third instar was the most vulnerable stage. Pyriproxyfen had significant effects on development for all immature C. rufilabris that successfully developed to adults with variations among the developmental stages and concentrations. The overall developmental duration from eggs to adults when eggs, first, and third instars were treated were 2.6,4.2, 2.4,4.1 respectively, and 6.0,7.1 d longer than those in water control, respectively. However, the overall developmental durations from eggs to adults were 0.5,1.2 d shorter than in water control when the second instars were treated with pyriproxyfen. The compatibility of pyriproxyfen with natural enemies in integrated pest management programs is discussed. [source] | ||||||||||