Aphid Survival Experiment Lab Report

RESULTS
Aphid survival experiment
Aphid survival rate varied with both of different combinations of predators-aphids and various times in presence or absence of ants (Table 2). GLM results showed that the interaction of ‘time × different combinations of predators and aphids × ant’ (F = 0.211; df = 10, 317; P = 0.995), ‘ant × time’ (F = 0.490; df = 2, 317; P = 0.613) and ‘different combinations of predators and aphids × time’ (F = 1.639; df = 10, 317; P = 0.095) on the survival rate were not significant. However, the interactions of different combinations of predators and aphids × ants were significant (F = 2.715; df = 5, 317; P = 0.020). Moreover, the results indicated that the effect at different times (F = 11.74; df = 2, 317; P = 0.000),
24.4% in presence of ants after 72 h). Besides the results showed us that the treatments in which one and three individuals of fourth instar larvae of C. septempunctata were present, the predators did consume more nymphal stages of A. gossypii than in any other treatment (Table 2). Furthermore, in the experiment with coccinellid larvae, more aphids were found alive when C. septempunctata larvae were placed in the ant-present treatment and combination treatment (L3CC + L4CS) (with or without ants) compared in the treatment in which during 24 hours the aphids were present together with coccinellids in the absence of ants (Fig. 1, Table
According to table 3, symbiotic ants could have a role on the survival rate of C. carnea in treatment with three L3CC. GLM results indicated that different interactions between times (F = 6.265; df = 2, 117; P = 0.003), the presence or absence of ants (F = 13.573; df = 1, 117; P = 0.000) and the presence or absence of aphids (F = 36.821; df = 1, 117; P = 0.000) did have significant impacts on lacewing survival rate, but conversely the interactions between ‘time × aphid × ant’ (F = 0.284; df = 2, 117; P = 0.753), ‘ant × aphid’ (F = 0.307; df = 1, 117; P = 0.581), ‘ant × time’ (F = 0.180; df = 2, 117; P = 0.835) and ‘aphid × time’ (F = 0.022; df = 2, 117; P = 0.978) did not have significant impacts on the survival rate of lacewings. In the treatment with three lacewing larvae (without extraguild prey and symbiotic ants) and considering whole eleven repeats, fifteen larvae of the thirty three larvae of lacewing remained alive after 72h. When aphid added to these treatments, the survival rates were increased. In contrast, when symbiotic ants were added to experiment without aphids the lacewing survival rate increased, but the increases were less than the treatments with aphids' presence (Table 3). Moreover, when both symbiotic ants and extraguild prey were added to three lacewing larvae treatments, the cannibalism level decreased about 0%, 10% and 11.11% after 24 h,