FAO plant protection paper 21. "Recommended methods for
measurement of pest resistance to pesticide" Contents - Previous
- Next J. R. Busvine, 1980. Statistical Principles of the
Detection and Measurement of Resistance Correction for Control
Mortality It should be noted that the mortality observed in
bioassay tests may not all be due to the pesticide, since
handling and holding operations may also be lethal to some of
the arthropods. This can be checked by using batches of
controls, which are treated in the same way, except for use of
pesticide. If it is assumed that deaths from handling and from
the pesticide are quite independent and uncorrelated, then a
correction for control mortality can be made by the use of
Abbott's formula, as follows: Two comments on this correction
may be of interest. Firstly, the change effected by its use is
greatest at low mortalities and becomes very small near 99%
mortality; secondly, the correction is virtually negligible when
control mortalities are below 5%. As has been stat