TABLE 2.

Bacterial populations in 7-day-old pea aphids Acyrthosiphon pisum reared from birth on the host plant Vicia faba cv. The Sutton^a

Aphid clone	Fresh wt (mg)b	Buchnera titer (no. of groEL gene copies per insect × 108)c	Serratia titer (no. of groEL gene copies per insect × 108)d	Buchnera density (no. of groEL gene copies per mg of body wt × 108)e	Serratia density (no. of groEL gene copies per mg of body wt × 108)f
IS	2.1 ± 0.12	12.3 ± 1.21	0.3 ± 0.033	3.3 ± 0.36	0.2 ± 0.02
AISTIS	3.7 ± 0.40	13.3 ± 0.97	1.7 ± 0.58	3.5 ± 0.26	0.5 ± 0.16

^aAll data represent means ± standard errors (n = 5).

^bTwo-tailed t test result: t₈ = 3.9 (0.01 > P > 0.001).

^cTwo-tailed t test result: t₈ = 0.7 (P not significant).

^dTwo-tailed t test result: t₈ = 2.3 (0.05 > P > 0.01).

^eTwo-tailed t test result: t₈ = 0.5 (P not significant).

^fTwo-tailed t test result: t₈ = 2.6 (0.05 > P > 0.01).