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significant differences among the different proportions (P) of trBC2 for plant height, biomass,
seed weight, seed number and reproductive allocation, but that was not the case for thousandseed
weight. The plant stage (F) when the insects were deposited had effects on biomass, seed
weight a nd num ber, and t housand-seed w eight, but not r eproductive a llocation: t he va lues
were lower for t he early fl owering plants. T here w ere s ignificant i nteractions be tween t he
presence of insects and plant type (I*T) for biomass, seed number and weight, and between
the presence of insect and the proportion of transgenic plants (I*P) for biomass, seed number
and weight and reproductive allocation. There was no i nteraction among the three controlled
factors (Table 3.9).
Under no i nsect pressure, there was no r elationship between the six variables and the
proportion of trBC2 plants, whatever ntrBC2 or trBC2. A maximum value was observed for
both types of plant at P50 (Fig. 3.9). Under insect pressure, both trBC2 and ntrBC2 showed a
trend to increase their performances with increasing proportions of trBC2, but the regression
was significant for seed weight (P=0.05) and for reproductive allocation in ntrBC2 (P