Table 1.

Major achievements in genome editing (GE) for tree crops and the prospects for its application in palms.

Sl. No	Species	Target gene(s)	Strategy	Features	Reference
1	Cocoa	TcNPR3 (Non-Expressor of Pathogenesis-Related 3)	CRISPR/Cas9	Knock down of defense suppressor TcNPR3 resulted in enhanced resistance to pathogen Phytophthora tropicalis	Fister et al., 2018
2	Elaeis guinensis	EgPDS (phytoene desaturase) and EgBRI1 (brassinosteroid-insensitive 1)	CRISPR/Cas9	Electroporation based transformation of protoplast showed 62.5-83.33% and 58.82-100% mutation frequency	Yeap et al., 2021
3	Sweet orange	CsPDS (phytoene desaturase)	CRISPR/Cas9 sgRNA	Agrofiltration utilizing Xcc targeting carotenoids biosynthesis caused 3.2-3.9% mutation but no albinos	Jia and Wang, 2014
4	Apple	Reporter gene uidA	ZFN (Zinc finger nuclease)	Stable and heritable gene mutation	Peer et al., 2015
5	Populus tomentosa	PtoPDS (phytoene desaturase)	CRISPR/Cas9	Mutation efficiency of 51.7% and albino phenotypes	Fan et al., 2015
6	Hevea brasiliensis	flowering time related genes (HbFT1, HbFT2 and HbTFL1−1, HbTFL1−2, HbTFL1−3)	CRISPR/Cas9	Used endogenous U6 promoters in protoplasts	Dai et al., 2021
7		HbPDS(phytoene desaturase)	CRISPR/Cas9	Stable transformation	Dai et al., 2021
8	Eucalyptus grandis	CCR1 (cinnamoyl-CoA Reductase1), IAA9A (an auxin-dependent transcription factor of Aux/IAA family)	CRISPR/Cas9	Wood-related genes edited in Eucalyptus hairy root	Dai et al., 2020
9	Elaeis guinensis	EgPDS (phytoene desaturase)	CRISPR/Cas9	Albino phenotypes with a mutation efficiency of 62.5–83.33%.	Yeap et al., 2021
		EgBRI1 (brassinosteroid-insensitive 1)	CRISPR/Cas9	premature necrosis and stunted phenotype	Yeap et al., 2021
		EgWRKY, DREB1, EgRBP42, EgEREBP and EgNAC	Base editing	Abiotic stress tolerance	Yarra et al., 2020
10	Phoenix dactylifera	Pdpcs and Pdmt	–	Abiotic stress tolerance (Cd and Cr) resistance	Chaâbene et al., 2018
		Pdpcs and Pdmt	–	Abiotic stress tolerance (heavy metals)	Chaâbene et al., 2017
11	Cocos nucifera	*PTI5 *PR1, PR4, *pathogenesis-related genes transcriptional activator PT15-like gene, *thaumatin-like protein, HSP70, *glutathione S-transferase	–	Root (wilt) disease resistance	Verma et al., 2017
		NBS-LRR type resistant gene analogues	–	Root (wilt) disease resistance	Rajesh et al., 2015
12	Elaeis guineensis	Genes of agronomic importance (disease resistance, abiotic stress tolerance, dwarfness)	–	Ganoderma disease, abiotic stress tolerance, ease of harvesting traits such as dwarf, long stalk	Yeap et al., 2021
13	Phoenix dactylifera	Genetic markers for sex determination	–	Early determination of sex distinguishes dioecious palms	Sattar et al., 2017
		Resistance genes in SNP desert of date palm	–	Abiotic and biotic stress tolerance	Sattar et al., 2017