Open AccessControl of Tobacco mosaic virus by PopW as a Result of Induced Resistance in Tobacco Under Greenhouse and Field Conditions
Author(s) -
Jiangang Li,
Jing Cao,
Feifei Sun,
Dongdong Niu,
Fang Yan,
Hongxia Liu,
Jianhua Guo
Publication year - 2011
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-02-11-0049
Subject(s) - tobacco mosaic virus , nicotiana tabacum , tobamovirus , ralstonia solanacearum , biology , salicylic acid , phenylalanine ammonia lyase , systemic acquired resistance , peroxidase , horticulture , plant disease resistance , nicotiana , solanaceae , bacterial wilt , hydrogen peroxide , pathogenesis related protein , catalase , microbiology and biotechnology , pathogen , virus , virology , enzyme , biochemistry , gene , arabidopsis , mutant
In a previous study, we isolated a new harpin protein, PopW, from the bacterium Ralstonia solanacearum ZJ3721 that can induce a hypersensitive response in tobacco, Nicotiana tabacum, leaves. In the current study, we demonstrate that, in a greenhouse experiment, PopW induced tobacco-acquired resistance against the Tobacco mosaic virus (TMV) with a biocontrol efficacy of 80.9 to 97.4% at a concentration as low as 25 μg/ml in both PopW-treated and neighboring leaves. The resistance induced by PopW is systemic acquired resistance mediated by salicylic acid, which was certified by the development of resistance being accompanied by the expression of the pathogenesis-related-1 gene (PR1) 8 h after PopW was sprayed onto the tobacco leaves. In addition, hydrogen peroxide began to accumulate 10 h after PopW spraying, peaking at 24 h with a maximum concentration of 1.97 μM/g fresh weight. The activities of phenylalanine ammonia lyase (EC4.3.1.5), polyphenoloxidase (EC1.14.18.1), and peroxidase (EC1.11.1.7) also increased, peaking at different times in the PopW-treated tobacco leaves. PopW also reduced the level of TMV disease in field trials with a biocontrol efficacy of 45.2%. Furthermore, PopW both increased tobacco yield (by 30.4 more than in control plants) and improved tobacco foliar quality, with an increase of 50.2% in the number of first-class tobacco leaves from treated compared with untreated plants. All of these results indicate that the new harpin protein PopW has the potential to be an effective biocontrol agent against TMV in tobacco.