Fig. 3. Variation in (A) the relative growth rate (RGR) and (B) the estimated
intrinsic rate of population increase (Rm) of aphids
developing from offspring raised on `young' and `old' diets (circles) and for
`pre-tuber-filling' and `tuber-filling' plants (squares). Values are either
the mean RGR ± S.E.M. (N=8-15) or the mean
Rm ± S.E.M. (N=7-14) for clones of
Myzus persicae (open symbols) or Macrosiphum euphorbiae
(closed symbols). Points falling below the line of equivalence indicate clones
that perform better on the `young' diet. *Clones showing a
significant difference, in post-hoc analysis, between `young' and `old' diets.
ANOVA for RGR: diet: F1,129=13.57, P<0.001;
species: F1,129=10.72, P<0.05; interaction:
F1,129=0.37, P>0.05; clone (subspecies):
F4,129=5.60, P<0.001. ANOVA for
Rm: diet: F1,120=31.95,
P<0.001; species: F1,120=37.87,
P<0.001; interaction: F1,120=1.43,
P>0.05; clone (subspecies): F4,120=4.75,
P<0.01.