Table 1.

The major classes of plant immune inducers

Attributes	Names	Origin	Refs.
Proteins	Harpin	Pseudomonas syringae	(Dong et al. 1999)
	Siderophore	Pseudomonas fluorescens	(Leeman et al. 1996)
	Flagellin	Pseudomonas syringae	(Felix et al. 1999)
	Nep1-like protein	Bacillus halodurans	(Oome et al. 2014)
	AMEP412	Bacillus subtilis	(Shen et al. 2019)
	SodM	Escherichia coli	(Watt et al. 2006)
	EF-Tu	Escherichia coli	(Kunze et al. 2004)
	PGN	Staphylococcus aureus	(Gust et al. 2007)
	CSP	Staphylococcus aureus	(Felix and Boller 2003)
	PeBL1	Brevibacillus laterosporus	(Wang et al. 2015)
	EG1(GH45)	Rhizoctonia solani	(Ma et al. 2015a)
	EIF	Trichoderma viride	(Fuchs et al. 1989)
	Nip1	Rhynchosporium commune	(Rohe et al. 1995)
	MgSM1	Magnaporthe grisea	(Yang et al. 2009)
	PemG1	Magnaporthe oryzae	(Peng et al. 2011)
	Ave1	Verticillium dahliae	(de Jonge et al. 2012)
	PevD1	Verticillium dahliae	(Wang et al. 2012a)
	PebC1	Botrytis cinerea	(Zhang et al. 2014c)
	BcGs1(GH15)	Botrytis cinerea	(Zhang et al. 2015)
	BcIEB1	Botrytis cinerea	(Frias et al. 2016)
	BcPGs (GH28)	Botrytis cinerea	(ten Have et al. 1998)
	T4BcPG1	Botrytis cinerea	(Poinssot et al. 2003; Zhang et al. 2014b)
	Hrip	Alternaria tenuissima	(Kulye et al. 2012)
	AsES	Acremonium strictum	(Chalfoun et al. 2013)
	SsCut	Sclerotinia sclerotiorum	(Zhang et al. 2014a)
	Cyclodipeptides	Eupenicillium brefeldianum	(Chen et al. 2015)
	CS20EP	Fusarium oxysporum	(Shcherbakova et al. 2016)
	RALF	Fusarium oxysporum, Arabidopsis	(Pearce et al. 2001; Thynne et al. 2017)
	Six4	Fusarium oxysporum	(Houterman et al. 2008)
	Six1	Fusarium oxysporum	(Rep et al. 2004)
	SnTox1	Stagonospora nodorum	(Liu et al. 2012b)
	PB90	Phytophthora boehmeriae	(Wang et al. 2003)
	Elicitin	Phytophthora capsici	(Ricci et al. 1989)
	OPEL (GH16)	Phytophthora parasitica	(Chang et al. 2015)
	GP42	Phytophthora sojae	(Nurnberger et al. 1994)
	AEP1	Phytophthora sojae	(Xu et al. 2021)
	PC2	Phytophthora infestans	(Wang et al. 2021)
	SCR96	Phytophthora cactorum	(Chen et al. 2016)
	CBEL	Phytophthora parasitica	(Gaulin et al. 2006)
	PcF	Phytophthora cactorum	(Orsomando et al. 2001)
	XEG1	Phytophthora sojae	(Ma et al. 2015b)
	GH17	Cladosporium fulvum	(Ökmen et al. 2019)
	NLP	Phytophthora parasitica	(Böhm et al. 2014)
	TaMCA4	Puccinia striiformis f. sp. tritici	(Wang et al., 2012b)
	Coat protein	Tobacco mosaic virus	(Allan et al. 2001)
	Gr-VAP1	Heterodera rostochiensis	(Lozano-Torres et al. 2012)
	VmE02	Valsa mali	(Nie et al. 2019)
	VdCP1	Verticillium dahliae	(Zhang et al. 2017)
	VdPEL1	Verticillium dahliae	(Yang et al. 2018)
	AGLIP1	Rhizoctonia solani	(Li et al. 2019)
	BAR11	Saccharothrix yanglingensis	(Zhang et al. 2018b)
	CfPDIP1	Colletotrichum falcatum	(Ashwin et al. 2018)
	Fg12	Fusarium graminearum	(Yang et al. 2021)
	Systemin	Tomato	(Pearce et al. 1991)
	ATP synthase	Maize	(Schmelz et al. 2006)
Peptide	Phytosulfokine	Tomato	(Zhang et al. 2018a)
	AtPep1	Arabidopsis	(Huffaker et al. 2006)
	PIPs	Arabidopsis	(Hou et al. 2014)
	GmPeps	Soybean	(Lee et al. 2018; Pearce et al. 2010; Yamaguchi et al. 2011)
Carbohydrates	Exopolysaccharides	Xanthomonas campestris pv. vesicatoria	(Romeiro and Kimura 1997)
	Chitin	Agaricus bisporus	(Kaku et al. 2006)
	Oligochitosan	Fusarium solani	(Cabrera et al. 2006)
	Heptaglucoside	Phytophthora sojae	(Sharp et al. 1984)
	Xyloglucan	Rubus fruticosus	(Joseleau et al. 1992)
	D-allose	Oryza sativa	(Kano et al. 2010)
	Galactinol	Tobacco	(Kim et al. 2008)
	Trehalose	Arabidopsis	(Reignault et al. 2001)
	Laminarin	Arabidopsis	(Ménard et al. 2004)
	Lichenan	Tobacco	(Stübler and Buchenauer 1996)
	Mannan oligosaccharides	Carob	(Zang et al. 2019)
Lipids/Lipopeptides	Lipopolysaccharides	Staphylococcus aureus	(Dow et al. 2000)
	N-acyl-homoserine lactones	Serratia liquefaciens	(Schuhegger et al. 2006)
	Fatty acid amides	Spodoptera exigua	(Alborn et al. 1997)
	Surfactin	Bacillus amyloliquefaciens	(Rahman et al. 2015)
	Ergosterol	Cladosporium fulvum	(Granado et al. 1995)
	Fengycin	Bacillus amyloliquefaciens	(Farzand et al. 2019)
	Iturin	Bacillus amyloliquefaciens	(Han et al. 2015)
	Lokisin	Pseudomonas sp. COR10	(Omoboye et al. 2019)
	Eicosapentaenoic acid	Phytophthora infestans	(Bostock et al. 1981)
	Arachidonic acid	Phytophthora infestans	(Savchenko et al. 2010)
	Cerebroside	Magnaporthe oryzae	(Koga et al. 1998)
	Rhamnolipids	Pseudomonas aeruginosa	(Crouzet et al. 2020; Sanchez et al. 2012)
Nucleotides	Extracellular ATP	Arabidopsis	(Clark et al. 2011; Tanaka et al. 2014)
	Extracellular pyridine nucleotides		(Wang et al. 2019a)
Chemical	DL-β-aminobutyric acid		(Hong et al. 1999)
	Benzothiadiazole		(Oostendorp et al. 2001)
	2,6-dichloro isonicotinic acid		(Qian et al. 2006)
	Isotianil		(Kumar et al. 2018)
	Methiadinil		(Wang et al. 2017)
	Probenazole		(Yoshioka et al. 2001)
	Dufulin		(Li and Song 2017)
	4-fluorophenoxyacetic acid		(Wang et al. 2020)
	3-pentanol	Bacillus amyloliquefaciens	(Choi et al. 2014a)
	Pipecolic acid	Plants	(Návarová et al. 2012)
	2,4-diacetyl phloroglucinol	Pseudomonas fluorescens	(Chae et al. 2020)
	2,3-butanediol	Pseudomonas chlororaphis	(Kong et al. 2018)
	Hexadecane	Paenibacillus polymyxa
	Tridecane	Paenibacillus polymyxa	(Lee et al. 2012)