Specific PCR‐based detection of Phomopsis vexans the cause of leaf blight and fruit rot pathogen of Solanum melongena L.

Abstract

Significance and Impact of the Study: Phomopsis vexans is an important seed-borne pathogenic fungus responsible for leaf blight and fruit rot in brinjal. Current detection methods, based on culture and morphological identification is time consuming, laborious and are not always reliable. A PCR-based diagnostic method was developed with species-specific primers designed based on sequence data of a region consisting of the 5Á8S RNA gene and internal transcribed spacers, ITS 1 and ITS 2 of nuclear ribosomal RNA gene (rDNA) repeats of P. vexans. AbstractLeaf blight and fruit rot disease caused by Phomopsis vexans is a devastating disease of brinjal. The detection of P. vexans in plant parts and seeds of brinjal can be complicated, mainly when the inoculum is present at low levels and/or overgrown by fast-growing saprophytic fungi or other seed-borne fungi. A PCR-based diagnostic method was developed with specific primers designed based on sequence data of a region consisting of the 5Á8S RNA gene and internal transcribed spacers, ITS 1 and ITS 2 of nuclear ribosomal RNA gene (rDNA) repeats of P. vexans. The efficiency and specificity of primer pairs PvexF/PvexR designed were established by PCR analysis of DNA from P. vexans strains isolated from India and fungal isolates of other genera. A single amplification product of 323-bp was detected from DNA of P. vexans isolates. No cross-reaction was observed with any of the other isolates tested. The specific primers designed and employed in PCR detected P. vexans up to 10 pg from DNA isolated from pure culture. This is the first report on the development of species-specific PCR assay for identification and detection of P. vexans. Thus, PCR-based assay developed is very specific, rapid, confirmatory and sensitive tool for the detection of pathogen P. vexans at early stages.

Unveiling mechanisms for induced systemic resistance, resistance breeding and molecular marker‐assisted breeding against Phomopsis blight of Solanum melongena

“…A species-specific PCR-based assay was used to find and identify Phomopsis azadirachtae (Vedashree et al, 2015). A pair of novel PCR primers, PvexF/PvexR, was constructed to identify strains of P. vexans from eggplant seeds and diseased leaves (Udayashankar et al, 2019). There were approximately 58 sequenced strains of P. vexans available, of which six belonged to the CBS culture collection centre, Netherlands, and the remaining were from the Indian subcontinent.…”

“…A pair of novel PCR primers, PvexF/PvexR, was constructed to identify strains of P . vexans from eggplant seeds and diseased leaves (Udayashankar et al., 2019). There were approximately 58 sequenced strains of P .…”

Discovery and exploration of widespread infection of mycoviruses in Phomopsis vexans, the causal agent of phomopsis blight of eggplant in China

“…The pathogen of eggplant brown streak can pass through the infected seed coat, cotyledon and hypocotyl ( Thippeswamy et al., 2012 ), resulting in a low seed germination rate and poor seed vigor. The seed yield is often reduced or even lost in breeding fields due to the spread of the disease ( Das, 1998 ; Beura et al., 2008 ; Udayashankar et al., 2019 ). Eggplant brown streak was first reported in Nanjing, China in 1932 ( Teng, 1932 ).…”

Analysis of The Genome Sequence of Phomopsis Vexans: A Fungal Pathogen Causing Phomopsis Blight of Eggplant

“…To approach this goal, more information about Phomopsis vexans should be needed. Scientists have isolated, morphological and molecular characterized it [7,[9][10][11] . However, information about the genomic features of P. vexans which are indispensable for pathogenesis mechanism research is still lacking.…”