TABLE 6.

Effect of secondary metabolite type (gossypol and cucurbitacin B), concentration, and length of exposure on Buchnera titers in aphids from populations maintained on cotton or cucumber and fed artificial diets^a

Effect	Aphids maintained on cotton				Aphids maintained on cucumber
	df	Mean square	F	P	df	Mean square	F	P
Plant secondary metabolite (A)	1	0.00003993	11.11	0.0015	1	0.00031426	16.55	0.0001
Concn (B)	3	0.00000685	1.91	0.1382	3	0.00001200	0.63	0.5970
Length of exposure (C)	2	0.00002256	6.27	0.0034	2	0.00003630	1.91	0.1561
A × B	3	0.00001153	3.21	0.0293	3	0.00013989	7.37	0.0003
A × C	2	0.00000071	0.20	0.8221	2	0.00000133	0.07	0.9326
B × C	6	0.00000501	1.39	0.2317	6	0.00002258	1.19	0.3234
A × B × C	6	0.00000105	0.29	0.9388	6	0.00001214	0.64	0.6982

^aDetermined by three-way ANOVA.