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CP plants reached a maximum at T75 in the plot border (Figure 3.6). There was no difference
in pe rformance of N C a nd C P pl ants i n pur e pl ots i n e ither e xperiment ( Figure 3 .6). T he
resource allocation index for NC and CP plants did not differ between mixed and pure stands
(contrast test, P>0.05) for either plot position in either experiment.
Competition b etween s imulated i nsect- resistant and susceptible plants The relative
difference (DI) between NC and CP varied both with the plot position and between the two
experiments (Table 3 .7, F igure 3.7). From the first experiment to the second and from plot
center to border, there were fewer stands that had high DI values (Figure 3.7). According to
the Helmert contrast test, the DI value at T25 was higher than that at T50 in the center in both
experiments. The same was not true at the border (Table 3.7). DI at T75 was different from T25
and T50 for: 1) the plot center in the first experiment, 2) the plot border in the first experiment,
and 3) the plot border in the second experiment. DI between NC and CP in pure stands was
lower t han i n t he m ixed s tands. T he onl y e xception w as a t t he pl ot c enter i n t he s econd
experiment, where DI was lowest at T50 (Table 3.7).
Comparison of summed performances per plot Plot pos ition w as t he onl y s ignificant
factor within plots (Table 3.8). The group of plants at the plot border produced higher biomass
(3.5-fold in 2008 and 4.6-fold in 2009) and more viable seeds (3.1-fold in 2008 and 4.2-fold
in 2009) than the group in the plot center (P