List of abbreviations
HPLC	High-performance liquid chromatography is an analytical technique for the separation and quantification of chemical compounds
LC-MS/MS	Liquid chromatography—tandem mass spectrometry
LRR	Leucine-rich repeat
MALDI	Mass spectrometry technique matrix-assisted laser desorption/ionization
MALDI-TOF-MS	Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry
MALDI-TOF-MS/MS	Matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry
MAPK	Mitogen-activated protein kinases
RGA	Root growth assay
RTK	Receptor tyrosine kinase
RLK	Receptor-like kinase
SBT	Subtilisin-like serine proteinase
WT	Wild type
List of peptide acronyms
AtPep1	The 23-amino acid peptide isolated from extracts of Arabidopsis leaves, exhibiting characteristics of an endogenous elicitor of the innate immune response [20], the first member of the Pep (plant elicitor peptides) family [22]
CEP	C-terminally encoded peptide [34]
CIF	Casparian strip integrity factor 1 [48]
CLE	CLAVATA3/EMBRYO SURROUNDING REGION-related [30]
CLEL	CLE-like peptide [54]
GLV	GOLVEN peptide [55]
HypSys	Hydroxyproline-rich peptide systemin [18,77]
Pep	Plant elicitor peptide [22,23]
RALF	Rapid alkalinization factor [27]
RGF	Root meristem growth factor peptide [46]
PSY	Plant peptide containing sulfated tyrosine [9]
TDIF	Tracheary element differentiation inhibitory factor peptides [33]