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Title: ANTHRACNOSE RESISTANCE GENE2 confers fungal resistance in sorghum
SUMMARY Sorghum is an important food and feed crop globally; its production is hampered by anthracnose disease caused by the fungal pathogenColletotrichum sublineola(Cs). Here, we report identification and characterization ofANTHRACNOSE RESISTANCE GENE 2(ARG2) encoding a nucleotide‐binding leucine‐rich repeat (NLR) protein that confers race‐specific resistance toCsstrains.ARG2is one of a cluster of severalNLRgenes initially identified in the sorghum differential line SC328C that is resistant to someCsstrains. This cluster shows structural and copy number variations in different sorghum genotypes. Different sorghum lines carrying independentARG2alleles provided the genetic validation for the identity of theARG2gene.ARG2expression is induced byCs, and chitin inducesARG2expression in resistant but not in susceptible lines. ARG2‐mediated resistance is accompanied by higher expression of defense and secondary metabolite genes at early stages of infection, and anthocyanin and zeatin metabolisms are upregulated in resistant plants. Interestingly, ARG2 localizes to the plasma membrane when transiently expressed inNicotiana benthamiana. Importantly,ARG2plants produced higher shoot dry matter than near‐isogenic lines carrying the susceptible allele suggesting an absence of anARG2associated growth trade‐off. Furthermore, ARG2‐mediated resistance is stable at a wide range of temperatures. Our observations open avenues for resistance breeding and for dissecting mechanisms of resistance.  more » « less
Award ID(s):
1916893
PAR ID:
10391814
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
The Plant Journal
Volume:
113
Issue:
2
ISSN:
0960-7412
Page Range / eLocation ID:
p. 308-326
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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