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A new leaf blight disease of browntop millet (Brachiaria ramosa) was noticed during rainy season (Kharif) 2018 at small millet experimental field, University of Agricultural Sciences, Gandhi Krishi Vignana Kendra (GKVK), Bengaluru, India. To assess the disease severity, an intensive roving survey was conducted during the 2019 cropping season. Based on the morphological characterization, the causal agent of leaf blight disease was identified as Bipolaris spp. Further sequencing and combined gene analysis of ITS (internal transcribed spacer of rDNA), GAPDH (glyceraldehyde 3‐phosphate dehydrogenase) and LSU (large subunit) of all the nine isolates confirmed the pathogen as B. setariae. Pathogenicity study showed that all the isolates were pathogenic and caused leaf blight symptoms on browntop millet. The B. setariae isolates showed marked variability with respect to disease incidence on browntop millet (cv. Dundu korale) under artificial inoculation conditions. However, the host range was limited only to browntop millet and found non‐pathogenic to other six small millets examined. To our knowledge, this is the first completely described study on characterization of B. setariae causing leaf blight disease of browntop millet in India.

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Hollyhock is one important decorative plant grown in garden beds in different region of the the world. The ornamental plant is susceptible to many diseases caused by diverse pathogens. Among these viral pathogens can cause enormous damage to the ornamental plant. The aim of the present study was identification of begomovirus and DNA sateelites is associated with the yellow vein mosaic and enation leaf curl disease complex of hollyhock. The hollyhock plants showing the typical begomovirus-like symptoms were collected from Pusa campus, New Delhi (India). To know the status of the begomovirus, the total DNA isolated from the infected hollyhock was subjected to PCR amplification using primers specific to the begomovirus. The partial (1.2 kb) genome sequencing of ten hollyhock samples indicates the associated of begomovirus (nucleotide identities is more 95% among themselves). Therefore three representative samples (H1, H2, H3) full-length genome (DNA-A, betasatellite and alphasatellite) was amplified through RCA method. The pairwise comparision of complete genome of the begomoviruses, betasatellites and alphasatellites using Sequence Demarcation Tool (SDT) showed highest nucleotide (nt) identity of 88.0 to 92.7% (DNA-A) with Cotton leaf curl Multan virus, 92.5–96.7% with Ludwigia leaf distortion betasatellite and 90.4 to 93. 2% % with Ageratum enation alphasatellite. Further recombinantion analysis showed that the begomoviruses and DNA satellites under study was recombinants of previously reported begomoviruses and DNA sattelites. This is the first report of Cotton leaf curl Multan virus and DNA satellites associated complex disease of hollyhock in India.

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