On the relationship between the European red mite and apple leaf chlorophvll


  • Daniel L. Johnson Institute of Animal Resource Ecology University of British Columbia Vancouver, B.C.


Chlorophyll content of Delicious and McIntosh apple leaves is shown to be uncorrelated with numbers of the European red mite (ERM). Hypotheses regarding movement by the ERM are examined. It is concluded that there is no evidence that the ERM seeks out the least damaged leaves, nor can leaf damage be attributed to the mites present on the leaves. Movement unrelated to leaf quality explains the lack of correlation.


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