ecology of phasmids - KLUEDO - Universität Kaiserslautern
ecology of phasmids - KLUEDO - Universität Kaiserslautern
ecology of phasmids - KLUEDO - Universität Kaiserslautern
Create successful ePaper yourself
Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.
Adult female feeding preference & nymph performance 60<br />
Total Total phenol phenol content [% TAE]<br />
10<br />
8<br />
6<br />
4<br />
2<br />
0<br />
c<br />
d<br />
Pmarg<br />
b<br />
e<br />
Paequ<br />
c c<br />
d<br />
Parbo<br />
Pcord<br />
c<br />
f<br />
Pcule<br />
Pdari<br />
a a<br />
Pdila<br />
e<br />
Pgran<br />
a<br />
b<br />
Philinae<br />
d<br />
Philsp<br />
a<br />
f<br />
Phisp<br />
a a a a<br />
b b b<br />
Figure 4-5: Total phenol content <strong>of</strong> leaves from 15 food plant species <strong>of</strong> M. diocles. Total phenol content differed<br />
significantly among species (ANOVA, F = 44.60, df = 14, P < 0.01). Identical letters below boxes indicate no<br />
difference (Tukeys HSD unequal N, P > 0.05). Box-Whiskers show mean, standard deviation and 95 % confidence<br />
intervals <strong>of</strong> standard deviation.<br />
4.4.2 Preference <strong>of</strong> M. diocles adult females<br />
Feeding preference <strong>of</strong> adult M. diocles females differed significantly indicating that they differentiated<br />
among food plant species (Figure 4-6). The assessed preference pattern at the same time revealed broad<br />
interspecific similarities. P. marginatum seemed to represent a food source <strong>of</strong> high value within the<br />
range <strong>of</strong> species tested. P. peltatum was most similarly accepted as food compared to P. marginatum as<br />
its median MAI was closest to 0.5. As preferences for six more plant species were not different to<br />
P. peltatum they also seemed to range on a similar preference level with P. marginatum as M. diocles<br />
foods. Only four out <strong>of</strong> 14 species were preferred to P. marginatum, i.e. the MAI resulting from dual-<br />
choice feeding trials was significantly above 0.5 (as compared to MAI <strong>of</strong> P. peltatum). Three plant<br />
species were clearly avoided by adult females: presented with P. aequale, P. grande and P. perlascense<br />
the insects strongly preferred the reference P. marginatum.<br />
The measured leaf characters seemed not to function as defenses against herbivory by M. diocles.<br />
Preference for host species neither correlated with structural and physical parameters tested nor with<br />
total phenol contents <strong>of</strong> leaves (Figure 4-7). Likewise tannin contents <strong>of</strong> leaves seemed not to account<br />
for the observed preference pattern <strong>of</strong> M. diocles adult females (correlation analysis was dismissed due<br />
to rare presence <strong>of</strong> tannins). Assuming a defensive function <strong>of</strong> tannins the animals should have preferred<br />
the leaves <strong>of</strong> plant species missing tannins. This could not be confirmed (compare Figure 4-6 and<br />
Pimpe<br />
Ppelt<br />
Pperla<br />
Preti