Report of the State Entomologist of Connecticut for the year ... . 100 100 128 100 100 256 100 100 1 Mortality figures for 0° F. not based on survival of control inasmuch as mortality for thecontrol exceeded that for most of the treatments. Connecticut State Entomologist 301 These data represent percentage kill calculated on the basis of thosewhich survived in the corresponding control. The criterion for death was the failure of the larvae to none of those exposed for an hour or more to —25° and —30°
Report of the State Entomologist of Connecticut for the year ... . 100 100 128 100 100 256 100 100 1 Mortality figures for 0° F. not based on survival of control inasmuch as mortality for thecontrol exceeded that for most of the treatments. Connecticut State Entomologist 301 These data represent percentage kill calculated on the basis of thosewhich survived in the corresponding control. The criterion for death was the failure of the larvae to none of those exposed for an hour or more to —25° and —30° or pupated, a considerable number were active and lived for severaldays after exposure. In these tests a temperature zone is apparent below which a significantmortality occurs and above which mortality does not depart significantlyfrom that of the control groups. This point is clarified by the characterof the graphs in Figure 16. The duration periods of one, 16 and 256 S. multistriatusMORTALITY TRENDS I00r 90 80 70 60 > 50 o: 40o z s* 30 20 10-. Hours ExposureI 16- 256 .Control -20 -25 J30 0 -5 -10 -15 Exposure Temperature °FFigure 16. Cold intensity and the mortality trend of Scolytusmultistriatus larvae. 302 Connecticut Experiment Station Bulletin 472 hours were chosen arbitrarily, and mortality is plotted against the exposuretemperatures. No completely satisfactory method for correcting- the mor-talities occurring at 0° F., relative to the control, was found, and all pointsplotted on this figure represent the actual number of individuals whichdied for each treatment. It is interesting to note that in analysis there isno significant departure of the mortality at 0° and —5° F. from that ofthe controls. An abrupt rise in the slope of the line at the same tempera-ture in each instance graphically indicates the zone where the effect ofcold intensity is discernible. This occurs for every duration between —5°and —10° F. Since the average undercooling po
Size: 1310px × 1907px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorconnecti, bookcentury1900, bookdecade1900, bookyear1901
