Table 1.

Overview of experiments and summary of comparative non-targeted metabolome analyses performed in this study using flow injection time-of-flight mass spectrometry.

Strain a	Host Plant	Number of Biological Replicates			dpi a
WT	soybean	3			13
WT	soybean	3			21
WT	soybean	3			31
A9 (nifA mutant)	soybean	3			21
H1 (nifH mutant)	soybean	3			21
none (uninfected roots)	soybean	3			21
WT	cowpea	3			21
none (uninfected roots)	cowpea	3			21
WT	mungbean	3			21
none (uninfected roots)	mungbean	3			21
WT	siratro	3			31
none (uninfected roots)	siratro	2			31
Experimental Comparison a			# incr met b	# decr met c			Table
2.2. Host-Specific Nodule and Root Metabolome (4 host plants)
WT vs. none (uninfected roots)			132	21		Table S2
WT or none (soybean) vs. WT or none (cowpea, mungbean, siratro)			67	nd		Table S3
WT or none (mungbean) vs. WT or none (cowpea, soybean, siratro)			30	nd		Table S3
WT or none (siratro) vs. WT or none (cowpea, mungbean, soybean)			17	nd		Table S3
WT or none (cowpea) vs. WT or none (mungbean, soybean, siratro)			17	nd		Table S3
2.3. Metabolome of different stages of nodule development (soybean)
WT 13 dpi vs. 21 and 31 dpi			6	nd		Table 2
WT 21 dpi vs. 13 and 31 dpi			1	nd		Table 2
WT 31 dpi vs. 13 and 21 dpi			4	nd		Table 2
2.4. Metabolome of nodules induced by a nifA and nifH mutant (soybean)
WT vs. A9 (nifA mutant)			25	112
WT vs. H1 (nifH mutant)			19	69

^a: WT = wild type; dpi = days post inoculation; ^b: # incr met = number of metabolites showing a statistically significant increase (log₂ ≥ 0.5, q-value ≤ 0.01) in the comparison; ^c: # decr met = number of metabolites showing a statistically significant decrease (log₂ ≤ 0.5, q-value ≤ 0.01) in the comparison. nd = not determined.