Host-induced gene silencing of cytochrome P450 lanosterol C14α-demethylase-encoding genes confers strong resistance to Fusarium species.
Head blight, which is caused by mycotoxin-producing fungi of the genus Fusarium, is an economically important crop disease. We assessed the potential of host-induced gene silencing targeting the fungal cytochrome P450 lanosterol C-14α-demethylase (CYP51) genes, which are essential for ergosterol biosynthesis, to restrict fungal infection. In axenic cultures of Fusarium graminearum, in vitro feeding of CYP3RNA, a 791-nt double-stranded (ds)RNA complementary to CYP51A, CYP51B, and CYP51C, resulted in growth inhibition [half-maximum growth inhibition (IC50) = 1.2 nM] as well as altered fungal morphology, similar to that observed after treatment with the azole fungicide tebuconazole, for which the CYP51 enzyme is a target. Expression of the same dsRNA in Arabidopsis and barley rendered susceptible plants highly resistant to fungal infection. Microscopic analysis revealed that mycelium formation on CYP3RNA-expressing leaves was restricted to the inoculation sites, and that inoculated barley caryopses were virtually free of fungal hyphae. This inhibition of fungal growth correlated with in planta production of siRNAs corresponding to the targeted CYP51 sequences, as well as highly efficient silencing of the fungal CYP51 genes. The high efficiency of fungal inhibition suggests that host-induced gene-silencing targeting of the CYP51 genes is an alternative to chemical treatments for the control of devastating fungal diseases.
Institute for Phytopathology and Applied Zoology and Institute for Microbiology and Molecular Biology, Centre for Bio Systems, Land Use, and Nutrition, Justus Liebig University, D-35392 Giessen, Germany.
Aline
A
Koch
Neelendra
N
Kumar
Lennart
L
Weber
Harald
H
Keller
Jafargholi
J
Imani
Karl-Heinz
KH
Kogel
D017360:Arabidopsis / Q000382:microbiology*; D060467:Disease Resistance / Q000235:genetics*; D005670:Fusarium / Q000201:enzymology* / Q000235:genetics; D020868:Gene Silencing; D001467:Hordeum / Q000382:microbiology*; D010935:Plant Diseases / Q000382:microbiology*; D030821:Plants, Genetically Modified; D012330:RNA, Double-Stranded / Q000378:metabolism; D058886:Sterol 14-Demethylase / Q000235:genetics*
D012330:RNA, Double-Stranded; D058886:Sterol 14-Demethylase
Fusarium head blight; HIGS; RNA interference; crop protection; small interfering RNA