Molecular Characterization of Spot Blotch (Bipolaris Sorokiniana) of Wheat (Triticum Aestivum L.) and Its Management

Abstract

Spot blotch of wheat is one of the highly destructive disease in warm and humid regions of India which is caused by the fungal pathogen Bipolaris sorokiniana. In the present study, molecular characterization of the fungus was carried out based on amplification of DNA using PCR assay which resulted in size 562bp. After sequencing the fungal pathogen was characterized as Bipolaris sorokiniana isolate Abs1 [0R117140.1]. Which showed 99.28%, 99.28%, and 99.10% sequence identity with Bipolaris sorokiniana strain BHURC3 [MH208980.1], Bipolaris sorokiniana strain SA 3051 [MH197354.1], Setosphaeria rostrata strain UAS BW 10376[MH201154.1] respectively. Four different fungicides were evaluated against mycelial growth, of Bipolaris sorokiniana. Propiconazole 25% EC and Tebuconazole 25% EC proved to be the best to inhibit the Bipolaris sorokiniana with 100% inhibition even at lowest conc. In experiment of botanicals, the maximum mycelial inhibition (44.71%) was observed in Turmeric rhizome extract at 10% concentration. While among different bio agents, Trichoderma harzianum effectively inhibited the mycelial growth of Bipolaris sorokiniana with 75.55% inhibition. Two foliar sprays of Propiconazole 25% EC @ 0.1% at tillering and booting stage under timely sown condition is best for management of spot blotch of wheat with significant increase in yield. Alternatively, two sprays of Tebuconazole 25% EC @ 0.1% also managed the pathogen in field conditions.