Table 3.

Recent applications of metabolomics platforms to decipher abiotic and biotic stress tolerance in major crop plants.

Crop	Stress Condition	Analytical Platform	Specific Tissue	Key Metabolites Produced	Data Analysis	Reference
Abiotic Stress Tolerance
Maize	Drought stress	RP/UPLC-MS/MS	Immature kernels	Metabolism of lipids, carbohydrates and glutathione cycle	PLS-DA KEGG	[14]
Maize	Drought stress	GC-TOF-MS	Multiple tissues	Adenine, phenylalanine, isoleucine, succinic acid, pyruvic acid, alanine, proline and xylose	ANOVA and PCA	[141]
Maize	Drought stress	GC/MS	Leaf blades	Myoinositol and glycine	ANOVA and PCA	[4]
Barley	Drought stress	MS-EI	Fifth leaf and Palea	Aromatic amino acids, proline, glutamine, threonine, aspartate, glycine and serine	PROC UNIVARIATE, SAS v. 9.4	[16]
Wheat	Drought stress	GC-MS	Roots and leaves	Malic acid, fumaric acid, citric acid, valine and tryptophan	PLS-DA, KEEG	[17]
Wheat	Drought stress	GC/MS	Flag leaves	Glutamine, serine, methionine, lysine and asparagine	MetabolomeExpress	[20]
Wheat	Drought stress	GC-TOF-MS	Shoots	Malic acid, mannose, fructose, sucrose and proline	SIMCA 14.0, PCA, KEGG, MetaboAnalyst	[128]
Rice	Drought stress	GC-MS	Leaves	4-hydroxycinnamic acid, ferulic acid, stearic acid and xylitol	PCA, PLS-DA	[139]
Rice	Drought stress	GC/EI-TOF-MS	Leaf	Glutamate, proline, GABA, arginine and spermidine	TagFinder and NIST	[140]
Rice	Drought stress	GC/MS	Leaf blades	Serine, threonine and asparagine	PCA	[143]
Soybean	Drought Stress	H-NMR	Leaf	Glutamine, GABA, allantoin, pinitol and myoinositol	PCA	[142]
Sorghum	Drought stress	FT-IR and GC/MS	Leaf	Sugars and sugar alcohols	PC-DFA	[44]
Rice	Salt stress	GC/MS	Leaf	Mannitol and sucrose	ANOVA and MassHunter MS	[23]
Rice	Salt stress	GC-MS	Seedling	Leucine, isoleucine, valine, proline and GABA	ANOVA and DMRT	[15]
Rice	Salt stress	NMR	Leaf and root	Acetic acid, GABA, sucrose and non-polar metabolites	PLS-DA	[18]
Rice	Salt stress	GC-MS	Leaf	Vanillic acid, 4-hydroxybenzoic acid, palmitic acid, stearic acid, raffinose, L-tryptophan and pyruvic acid	PCA, PLS-DA and MetaboAnalyst 3.0	[146]
Wheat	Salt stress	GC/MS	Leaf	Proline, lysine, alanine and GABA	METABOLOMEEXPRESS	[9]
Wheat	Salt stress	HPLC	Roots and Shoots	Malic acid, proline, fructose, mannose, glycine, Glutamic acid	ANOVA, PCA,	[149]
Wheat	Salt stress	GC-TOF/MS	Leaf	Lysine, proline, sorbitol, lyxose and sucrose	PCA, OPLS-DA, KEGG and MetaboAnalyst	[144]
Maize	Salt stress	GC-MS	Leaf	Auxin, ABA	PCA, PLS-DA and SIMCA	[150]
Barley	Salt stress	GC/MS	Roots	Proline, sucrose, xylose and maltose	MetaboAnalyst	[147]
Tomato	Salt stress	UHPLC-ESI/QTOF-MS	Terminal leaflet	Sesquiterpene lactones, alkaloids and poluamines	ANNOVA, PCA, PLS-DA	[129]
Soybean	Waterlogging	CE/MS	Leaf	Phosphoenol pyruvate, NADH2, glycine and gammaaminobutyric acid	ANOVA	[22]
Soybean	Waterlogging	NMR	Roots and leaves	Isoflavones and kaempfero	ANOVA, PCA and MATLAB	[152]
Wheat	Waterlogging	GC/MS and LC/MS	Shoot	Lysine, proline, methionine and tryptophan	ANOVA and PCA	[153]
Rice	Waterlogging	GC/MS	Leaf	Glycine, alanine and GABA	PCA and MarkerLynx XS	[151]
Rice	Waterlogging	GC/MS and NMR	Leaf	6-phosphogluconate, phenylalanine and lactate	ANOVA and PCA	[154]
Wheat	Heat stress	LC-HRMS	Flag leaves	Pipecolate and L-tryptophan	PLS-DA, KEGG	[25]
Wheat	Heat stress	LC-MS/MS HPLC	Filling grains	G1p and sucrose	Metaboanalyst 2.0 and KEGG	[156]
Wheat	Heat stress	GC-MS	Leaves	Melibiose, serine, lysine, glycine, malic acid, mannitol, xylitol, inositol, fructose, proline, glutamic acid and alanine	LSD	[158]
Tomato	Heat stress	GC-MS	Fruit pericarp	Rhamnose, putrescine, myoinositol, allantoin and alanine	PCA	[155]
Tomato	Heat stress	LC-QTOF-MS	Pollens	Flavonoids	MetAlign, METLIN, PCA and ANNOVA	[159]
Soybean	Heat stress	LC-MS, GC-MS	Seed	Ferulate, naringenin-7-O-glucoside, genistein, glycitein and apigenin	PCA	[157]
Maize	Heat stress	NMR	Leaf	Sucrose, fructose, GABA, aspartate, asparagine, valine, inositol, analine and proline	PCA and SIMCA	[160]
Canola	Metal stress	NMR	Roots and leaves	Hydroxycinnamic acids and glucosinolates	PCA, ANOVA and MultiExperiment Viewer	[163]
Sunflower	Metal stress (Cr)	capHPLC-ESI(−)-QTOF-MS	Roots and leaves	Fatty acids	PLS and MetaboScape	[161]
Soybean	Metal stress (Mo)	UPLC	Roots and leaves	Citric acid, D-glucarate, gluconic, L-nicotine, and flavonoids/isoflavone	PCA, KEGG, Metlin	[43]
Wheat	Nitrogen stress	GC-MS and LC-MS	Leaf	Tyrosine, lysine, allo-inositol and L-ascorbic acid	MS-excel package	[11]
Wheat	Nitrogen stress	GC-TOF-MS	Leaf	Fucose, ribulose, lyxose, galactinol and erythritol	PCA	[166]
Wheat	Low-nitrogen stress	UPLC-QTOF	Flag leaf	Methylisoorientin-2″-O-rhamnoside, iso-orientin and iso-vitexin	PCA, OPLS-DA, Markerlynx XS™, SIMCA-P	[172]
Barley	Sulfur stress	UPLC	Roots and leaves	sulfur metabolites, organic acids and amino acids	PCA, ANOVA, MassLynx and Progenesis QI	[168]
Biotic stress tolerance
Wheat	Zymoseptoria tritici	FT-ICR-MS	Leaf	Flavonoids, hydroxycinnamic acid amides and cinnamyl alcohols	MetaboScape 4.0, DataAnalysis 5.0 and KEGG	[26]
Wheat	Fusarium graminearum	NMR	Leaf	Trehalose, asparagine, phenylalanine, myoinositol, 3-hydroxybutarate and L-alanine	PCA, MestReNova 9.1.0 and Matlab	[21]
Wheat	Fusarium graminearum	NMR	Spikelet	Spermine, putrescine, GABA, inositols, galactose and lactic acid	PCA, MestReNova 9.1.0 and Matlab	[180]
Wheat	Wheat streak mosaic virus	UPLC-QTOF/MS	Leaf	Reduction in some amino acids such as L-tyrosine, tryptophan, isoleucine and phenylalanine	PCA, KEGG, METLIN, MetFrag and MetaboAnalyst	[41]
Wheat	Fusarium graminearum	LC-LTQ-Orbitrap	Rachis and spikelet	Fatty acids, terpenoid, phenolic glycosides, flavonoid and phenylpropanoids	MetaXCMS	[179]
Wheat	Triticum turgidum	LC/MS	Leaf	benzoxazinoids	PCA, XCMS and CAMERA	[188]
Rice	Orseolia royzae	GC/MS	Leaf	Heneicosanoic acid, threonic acid, palmitoleic acid, palmitic acid, nonadecanoic acid and linoleic acid	ANOVA	[181]
Rice	Xanthomonas oryzae pv. oryzae	GC/TOF and LC/TOF	Leaf	Phenylalanine and tyrosine	KEGG, MassHunter, GeneSpring-MS 1.2 and METLIN	[182]
Rice	Magnaporthe grisea	NMR, GC/MS and LC/MS	Leaf	Cinnamate, proline, glutamine and malate	PCA and MATLAB	[183]
Rice	Rhizoctonia solani	CE/TOF-MS	Leaf	Jasmonic acid, mucic acid and glyceric acid	MPP software	[42]
Rice	Nilaparvata lugens	GC/MS	Leaf sheath	GABA and glyoxylate	PCA and PLS-DA	[186]
Rice	Chilo suppressalis	UHPLC-MS and GC-MS	Leaf	Terpenoids and phenylpropanoids	KEGG	[187]
Maize	Fusarium graminearum	LC/MS	Roots	metabolites smiglaside and smilaside A	ANOVA and SAS software	[24]
Maize	Bipolaris maydis	FT-IR and NMR	Leaf	lignin, flavonoids and polyphenols	PCA	[184]
Maize	Ostrinia furnacalis	HPLC-MS/MS	Leaf	Phtohormones and benzoxzinoids	KEGG, PLS-DA	[185]
Tomato	Pseudomonas syringae pv	NMR and LC/MS	Leaf	Flavonoid and phenylpropanoids	PCA, PLS-DA	[178]
Rice	Lolium perenne	LC-QTOF-MS	Root and shoot extracts	3,5,6,7,8-pentahydroxy flavones, p-hydroxybenzoic acid and sinapyl alcohol	ANOVA and LSD	[189]
Wheat	Weeds	LC-MS/MS Q Trap	Root and shoot extracts	Benzooxazinoids	Analyst software	[190]
Wheat	Lolium rigidum Urochloa panicoides	LC-MS/MS Q Trap	Root and shoot extracts	Hydroxamic acids and Benzoxazinoids	Analyst software	[191]
Legumes	Weeds	UHPLC QTOF-MS	Root and shoot extracts	Flavonoids	METLIN	[192]
Wheat	Pathogen resistance	Py-FIMS	Soil rhizosphere	Glutarimide, consabatine, methylpyrrole, arachidonic acid, gibberellic acid and diacetyllycopsamine	PCA	[194]
Cereals	Rhizoctonia solani	LC/MS and 1H NMR	Soil rhizosphere	macrocarpal	PCA, PLS-DA, ANOVA and Matlab	[195]
Crop plants	Bacillus subtilis	NMR	Soil rhizosphere	Antimicrobial compounds	PCA	[196]