Biology and Management of Spot Blotch Pathogen Bipolaris sorokiniana of Wheat

Unraveling the dynamics of wheat leaf blight complex: isolation, characterization, and insights into pathogen population under Indian conditions

“…One of the pathogens that affect all wheat parts, including seeds, roots, shoots, and leaves, is B. sorokiniana (teleomorph, C. sativus ). Spot blotch disease, which is believed to be a complex of B. sorokiniana and P. tritici-repentis , is a widespread disease on wheat across many continents ( Al-Sadi et al, 2002 ; Neupane et al, 2010 ; Al-Sadi, 2016 ; Devi et al, 2018 ; Gultyaeva et al, 2018 ; Gupta et al, 2018 ; Aggarwal et al, 2022 ), with losses reaching up to 16–43 percent ( Ayana et al, 2018 ; Devi et al, 2018 ), particularly in the warm and humid regions of the world. The importance of this disease was recognized in India only during the Green Revolution when most of the introduced semi-dwarf wheat varieties were found to be susceptible to it ( Gupta et al, 2018 ).…”

“…It is reported that the incidence of common root rot is dependent on the soil inoculum present at the time of planting ( Boer et al, 1991 ). Moreover, spot blotch disease, being soil-borne, can be initiated from the inoculum surviving in soil or on straw ( Chand et al, 2002 ; Pandey et al, 2005 ; Aggarwal et al, 2022 ). This suggests that management techniques should not only focus on decreasing the presence of the fungus in plant aerial parts but also on the inoculum present in soil ( Al-Sadi, 2021 ).…”

“…Spot blotch is primarily a seed-borne disease, but infection can also be initiated by inoculum surviving on crop residues, collateral hosts, resting mycelium, or conidia surviving in soil ( Chand et al, 2002 ; Pandey et al, 2005 ). Although other pathogens have been found to be associated with the disease in the past, they are either non-pathogenic or do not cause substantial losses ( Mehta, 1998 ), hence, they have never been well explored ( Aggarwal et al, 2009 ; Bandyopadhyay et al, 2016 ; Aggarwal et al, 2022 ; Kashyap et al, 2023 ). The present study was conducted with the purpose of determining and comparing the extent of variability among the pathogens associated with the HLB/spot blotch complex, highlighting their current status in different wheat-growing zones of India.…”