Table 2.

Results of GLMs for the main effects of AM fungi (–/+), P addition (–/+), aphids (–/+) (n=6), and their two-way and three-way interactions on plant nutrition, plant growth, concentration of soil PO₄, attractiveness of plant headspace samples to aphids, percentage of root length colonized by AM fungi, and final aphid biomassP values <0.05 are highlighted in bold. Direction of effect is indicated by shifts (↑, positive effect; ↓, negative effect). NA, not applicable.

	AM fungi			P			Aphids			AM fungi×P		P×aphids		AM fungi×aphids		AM fungi×P×aphids
	F		P	F		P	F		P	F	P	F	P	F	P	F	P
Total leaf P concentration	↑	16.5	0.000	↑	4.2	0.046	↓	18.5	0.000	0.0	0.894	0.1	0.741	0.0	0.926	0.7	0.401
Total leaf N concentration	↑	15.2	0.000		0.05	0.828	↓	7.5	0.009	1.9	0.171	2.2	0.143	0.4	0.514	0.5	0.488
N: P ratio	↓	4.2	0.044	↓	14.2	0.000	↑	19.1	0.000	0.5	0.477	0.4	0.557	3.3	0.077	0.6	0.461
Plant shoot mass	↑	7.9	0.007		0.07	0.797	↓	7.7	0.008	2.1	0.155	1.8	0.186	0.1	0.757	0.4	0.551
Plant root mass		1.7	0.194		2.5	0.124		1.1	0.295	0.3	0.615	0.0	0.879	0.3	0.603	0.9	0.362
Soil PO4 concentration		3.6	0.063	↑	10.5	0.002		0.4	0.512	0.9	0.357	0.8	0.369	0.1	0.782	0.5	0.506
Attractiveness of plants to aphids	↑	4.7	0.042		0.0	0.979		NA	NA	1.2	0.295	NA	NA	NA	NA	NA	NA
AM fungal colonization		NA	NA	↓	7.5	0.013		3.9	0.063	NA	NA	4.6	0.045	NA	NA	NA	NA
Aphid biomass		0.1	0.732		1.9	0.187		NA	NA	0.8	0.382	NA	NA	NA	NA	NA	NA