Table 1.

Fold changes of detected metabolites in roots of the three barley genotypes under LK stress

Metabolite name	Log2(LK/C)a			Metabolite name	Log2(LK/C)a
	XZ153	XZ141	LuDaoMai		XZ153	XZ141	LuDaoMai
Amino acid b				Sugars and polyols
L-Alanine	−0.1	− 0.53**	0.11	Maltose	−0.50**	−1.42**	− 0.93**
Valine	1.76**	2.85**	1.55**	Sucrose	0.47**	0.09	1.31**
L-Leucine	1.58**	2.30**	1.07**	Inositol	2.19**	1.69**	2.64**
L-Isoleucine	1.56**	1.36**	1.73**	Trehalose	1.52**	−0.32	1.33**
L-Proline	1.78**	1.76**	1.78**	Organic acid
Glycine	0.91**	1.03**	1.45**	Glycolic acid	1.98**	1.41**	1.94**
L-Serine	0.43**	0.55**	0.74**	Benzoic acid	1.28**	0.78**	1.18**
L-Threonine	0.86**	0.82**	0.91**	Maleic acid	3.71**	3.52**	4.55**
β-Alanine	−0.61**	−0.80**	−0.1	Succinic acid	−2.08**	−1.99**	−0.36**
L-Aspartic acid	−2.94**	−3.56**	−2.21**	Glyceric acid	2.17**	1.52**	2.02**
GABA	0.12	−0.82**	0.01	Fumaric acid	0.59**	0.57**	1.75**
L-Glutamic acid	−2.42**	−3.00**	−1.25**	Malic acid	−1.39**	−2.07**	−0.73**
L-Phenylalanine	0.59**	0.04	0.39**	Ketoglutaric acid	−4.0**	−5.30**	−4.47**
Ornithine	1.55**	0.24*	1.13**	Threonic acid	0.50*	0.67	1.54**
L-Lysine	2.40**	1.16**	0.28*	Ribotide	−1.00**	−1.53**	−3.72**
Tyrosine	0.05	−0.54**	−0.26	Shikimic acid	−0.15	− 0.06	1.07**
L-Asparagine	0.85**	−0.12	0.52**	Citric acid	−1.12**	−2.0**	−0.55**
L-Glutamine	3.55**	2.48**	2.60**	Quinic acid	0.08**	−0.35**	0.21*
Sugars and polyols				Ascorbic acid	0.42**	0.35*	0.62**
Xylose	2.95**	2.14**	3.00**	Hexadecanoic acid	0.99**	0.50*	1.02**
L-Arabinose	1.31**	1.11**	1.59**	Hexanoic acid	−0.56**	−0.11	0
Ribose	1.70**	0.82**	1.67**	Others
Xylitol	0.1	−0.05	0.50**	Urea	−3.68**	−5.74**	−6.00**
Glycerol	1.76**	1.17**	1.43**	Mannitol	0.63**	0.45	1.87**
2-Keto-L-gluconic acid	0.45**	0.13	−0.18*	Putrescine	5.28**	5.34**	5.35**
Fructose	3.84**	3.78**	4.56**	Uracil	2.98**	1.35**	1.95**
Galactose	2.82**	2.13**	3.55**	Pipecolinic acid	2.43**	4.33**	1.87**
Glucose	2.90**	2.56**	4.07**	Pyroglutamic acid	−0.06	−0.94**	0.92**
Sorbose	3.64**	3.36**	3.97**	O-Methyl-Inositol	1.15**	0.91**	1.14**

^aThe fold changes were calculated using the formula log₂ (LK/C), LK Low potassium, C control. ^bThe bolder parts of the table are the different categories of metabolites.* and ** indicate significant (p < 0.05) and highly significant difference (p < 0.01), respectively