Open AccessTwo Amino Acid Substitutions in the Coat Protein of Pepper mild mottle virus Are Responsible for Overcoming the L4 Gene-Mediated Resistance in Capsicum spp.
Author(s) -
Yoshikatsu Genda,
Ayami Kanda,
Hiroyuki Hamada,
Kyoko Sato,
Jun Ohnishi,
Shinya Tsuda
Publication year - 2007
Publication title -
phytopathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.264
H-Index - 131
eISSN - 1943-7684
pISSN - 0031-949X
DOI - 10.1094/phyto-97-7-0787
Subject(s) - biology , tobamovirus , pepper , tobacco mosaic virus , gene , potyvirus , mottle , movement protein , plant virus , virology , genetics , virus , potato virus y , strain (injury) , cultivar , coat protein , botany , horticulture , rna , anatomy
The Capsicum spp. L genes (L 1 to L 4 ) confer resistance to tobamoviruses. Currently, the L 4 gene from Capsicum chacoense is the most effective resistance gene and has been used widely in breeding programs in Japan which have developed new resistant cultivars against Pepper mild mottle virus (PMMoV). However, in 2004, mild mosaic symptoms began appearing on the leaves of commercial pepper plants in the field which possessed the L 4 resistance gene. Serological and biological assays on Capsicum spp. identified the causal virus strain as a previously unreported pathotype, P 1,2,3,4 . PMMoV sequence analysis of the virus and site-directed mutagenesis using a PMMoV-J of the P 1,2 pathotype revealed that two amino acid substitutions in the coat protein, Gln to Arg at position 46 and Gly to Lys at position 85, were responsible for overcoming the L 4 resistance gene.