The chemical inducer, BTH (benzothiadiazole) and root colonization by mycorrhizal fungi (Glomus spp.) trigger resistance against white rot (Sclerotinia sclerotiorum) in sunflower.
White rot caused by Sclerotinia sclerotiorum (SS) is one of the most devastating plant diseases of sunflower. Controlling this pathogen by available tools hardly result in acceptable control. The aim of this study was to elucidate the effects of plant resistance inducers, BTH (benzothiadiazole in Bion 50 WG) and arbuscular mycorrhizal fungi (AMF) on disease development of white rot in three sunflower genotypes. Defence responses were characterized by measuring the disease severity and identifying cellular/histological reactions (e.g. autofluorescence) of host plants upon infection. Depending on the host genotype, a single application of inducers reduced disease symptoms. Histological examination of host responses revealed that BTH and/or AMF pre-treatments significantly impeded the development of pathogenic hyphae in Iregi szürke csíkos and P63LE13 sunflower plants and it was associated with intensive autofluorescence of cells. Both localized and systemic induction of resistance was observed. Importantly, the frequency of mycorrhization of hybrid P63LE13 and PR64H41 was significantly increased upon BTH treatment, so it had a positive effect on the formation of plant-mycorrhiza interactions in sunflower. To our knowledge, this is the first report on the additive effect of BTH on mycorrhization and the positive effect of these inducers against SS in sunflower.
Plant Protection Institute, Szent István University , Páter K. u. 1, H-2100 Gödöllő , Hungary.
Rita
R
Bán
Plant Protection Institute, Szent István University , Páter K. u. 1, H-2100 Gödöllő , Hungary.
Gellért
G
Baglyas
Plant Protection Institute, Szent István University , Páter K. u. 1, H-2100 Gödöllő , Hungary.
Ferenc
F
Virányi
Plant Protection Institute, Research Centre for Agriculture, Hungarian Academy of Sciences , Herman O. u. 15, H-1022 Budapest , Hungary.
Balázs
B
Barna
Institute of Genetics and Biotechnology, Szent István University , Páter K. u. 1, H-2100 Gödöllő , Hungary.
Katalin
K
Posta
Plant Protection Institute, Szent István University , Páter K. u. 1, H-2100 Gödöllő , Hungary.
József
J
Kiss
Plant Protection Institute, Szent István University , Páter K. u. 1, H-2100 Gödöllő , Hungary.
Katalin
K
Körösi
D001203:Ascomycota / Q000502:physiology*; D060467:Disease Resistance / Q000187:drug effects* / Q000502:physiology; D005838:Genotype; D006368:Helianthus / Q000235:genetics / Q000382:microbiology*; D054884:Host-Pathogen Interactions / Q000187:drug effects / Q000502:physiology; D025301:Hyphae / Q000502:physiology; D008856:Microscopy, Fluorescence; D038821:Mycorrhizae / Q000502:physiology*; D010935:Plant Diseases / Q000235:genetics / Q000382:microbiology*; D018517:Plant Roots / Q000235:genetics / Q000382:microbiology*; D013559:Symbiosis / Q000502:physiology; D013830:Thiadiazoles / Q000494:pharmacology*
D013830:Thiadiazoles; C015700:benzo-1,2,3-thiadiazole
Arbuscular mycorrhizal fungi; Bion 50 WG; SAR; Sclerotinia rot; induced resistance