RNA silencing of PEX6 gene causes decrease in pigmentation, sporulation and pathogenicity of Fusarium oxysporum

Abstract

Peroxisomes are single membrane-bound organelles that play a pivotal role in various developmental processes in all eukaryotic cells. This study targeted the PEX6 gene, which encodes for peroxisomal biogenesis factor 6, by RNA interference (RNAi) in Fusarium oxysporum f. sp. lycopersici. Fusarium oxysporum is a soilborne filamentous, hemibiotrophic fungus that invades tomato roots and colonizes the xylem vessels, thereby causing complete wilting of infected tomato plants. The expression of FoPEX6 in F. oxysporum was found to be higher during early stages of growth and development. The FoPEX6 gene was isolated and a hairpin RNAi construct was prepared and introduced into F. oxysporum 4471 through glass-bead transformation. The fungal transformation status, i.e. integration, expression and presence of the intended small interfering RNAs (siRNAs), was confirmed by PCR, qPCR and stem-loop PCR, respectively. The silenced fungal transformants exhibited reduced pigmentation and a significant reduction in sporulation as compared to the wild type. They also showed dramatic reduction in pathogenicity (virulence) on tomato, based on root infection and fruit invasion assays. These results suggest that PEX6 has a central role in pigmentation, sporulation and pathogenicity in F. oxysporum.

Trichoderma harzianum antagonistic activity and competition for seed colonization against seedborne pathogenic fungi of sunflower

“…2017), 1 × 10 6 conidia per ml for F. culmorum and F. oxysporum (Touati‐Hattab et al . 2016; Tetorya and Rajam 2018)). Ten microlitres from a conidia suspension of each pathogen and TRIC8 was placed on microscope slides and mixed thoroughly, then 10 µl sucrose (1%) was added to stimulate germination.…”

“…Antagonistic effect of TRIC8 on conidial germination and germ tube length of the pathogens TRIC8 was prepared at the concentration of 1 9 10 7 conidia per ml, whereas the pathogens were used at pathogenic conidia concentrations (1 9 10 5 conidia per ml for A. alternata and B. cynodontis (Tanahashi et al 2016;Zhang et al 2017), 1 9 10 6 conidia per ml for F. culmorum and F. oxysporum (Touati-Hattab et al 2016;Tetorya and Rajam 2018)). Ten microlitres from a conidia suspension of each pathogen and TRIC8 was placed on microscope slides and mixed thoroughly, then 10 µl sucrose (1%) was added to stimulate germination.…”

Optimization of Production Conditions for Protoplasts and Polyethylene Glycol-Mediated Transformation of Gaeumannomyces tritici

“…A 1790 bp PtrpC-hph fragment containing hph under the control of trpC gene promoter was amplified from plasmid pSilent-1 [ 34 , 35 , 36 ]. The hph fragment was polymerase chain reaction (PCR)-amplified from pSilent-1 using the primers HygbF (5′-TAACCGTATTACCGCCTTTG-3′) and HygbR (5′-TCGGCATCTACTCTATTCCTTT-3′) in a total reaction volume of 25 μL containing 0.75 μL PCR forward primer (10 μM), 0.75 μL PCR reverse primer (10 μM), 1 μL DNA sample of plasmid pSilent-1, 10 μL RNase free dH 2 O, and 12.5 μL PrimeSTAR Max (Takara, Dalian, China).…”

Potato dry rot disease: current status, pathogenomics and management

“…cubense (Ghag and Ganapathi 2019), tomato against F. oxysporum f. sp. lycopersici (Singh et al 2020;Tetorya and Rajam 2018), barley against F. graminearum (Koch et al 2016) and tobacco against F. verticillioides (Tinoco et al 2010). Unfortunately, there is not a single report of RNAi-mediated disease suppression in dry rots in potato.…”