. 2019 Jul 4;9:9650. doi: 10.1038/s41598-019-45702-1

Table 2.

Test statistics of the linear models used to explore effects of drought and diversity treatments on barley performance.

Explanatory variables	Seed mass			Shoot biomass		Root biomass		Shallowest root-layer		Intermediate root-layer		Deepest root layer
Explanatory variables	D.f.	F	p	F	p	F	p	F	p	F	p	F	p
Drought	1	11.33	0.001	35.37	<0.001	41.12	<0.001	12.86	0.001	0.14	0.70	13.37	<0.001
Barley richness	1	0.50	0.48	0.97	0.33	9.61	0.002	2.84	0.09	0.34	0.55	2.04	0.16
AMF richness	1	1.90	0.17	4.25	0.041	4.04	0.046	2.83	0.09	2.62	0.10	8.89	0.003
Colonization frequency	1	0.02	0.90	0.33	0.56	10.59	0.001	0.81	0.37	1.76	0.18	3.68	0.06
Drought: barley richness	1	0.34	0.56	2.70	0.10	3.24	0.07	1.12	0.29	0.21	0.64	0.69	0.41
Drought: AMF richness	1	0.00	0.95	0.04	0.84	0.87	0.35	2.69	0.10	0.49	0.48	1.69	0.20
Drought: colonization frequency	1	0.73	0.40	2.91	0.09	1.55	0.21	2.75	0.09	0.27	0.27	2.08	0.15
Barley richness: AMF richness	1	0.01	0.92	0.87	0.35	0.58	0.45	5.34	0.022	0.00	0.99	6.43	0.012
Barley richness: colonization frequency	1	1.00	0.32	2.78	0.10	5.85	0.017	1.38	0.24	0.82	0.36	0.42	0.52
AMF richness: colonization frequency	1	0.23	0.63	0.09	0.76	7.88	0.006	6.87	0.009	14.10	<0.001	0.05	0.83
Drought: barley richness: AMF richness	1	0.38	0.54	0.97	0.33	0.13	0.72	1.04	0.31	0.51	0.47	0.37	0.54
Drought: barley richness: colonization frequency	1	2.90	0.09	1.26	0.26	0.02	0.89	0.55	0.46	0.50	0.48	0.10	0.76
Drought: AMF richness: colonization frequency	1	2.59	0.11	4.53	0.035	0.04	0.84	0.00	0.97	0.57	0.45	0.32	0.57
Barley richness: AMF richness: colonization frequency	1	0.93	0.34	0.62	0.43	1.95	0.16	2.50	0.11	0.89	0.34	1.14	0.29
Adjusted R²	0.0567			0.2353		0.3303		0.1656		0.0584		0.1548
No. observations	149			143		150		150		150		150

The table shows degrees of freedom (D.f.), values of F statistic (F) and p values (p) for each main effect and interactions up to the 3rd order. Degrees of freedom (D.f.), values of F statistic (F) and p values (p) are presented for each main effect and interactions up to the 3rd order. Significant p values (p < 0.05) are highlighted in bold. Root layers (shallowest, intermediate, deepest) represent root biomass allocation to soil layers. Barley and AMF richness are treated as linear terms.