~ 2034 ~ Journal of Entomology and Zoology Studies 2021; 9(1): 2034-2039 E-ISSN: 2320-7078 P-ISSN: 2349-6800 www.entomoljournal.com JEZS 2021; 9(1): 2034-2039 © 2021 JEZS Received: 12-10-2020 Accepted: 10-12-2020 Gutha Venkata Ramesh Department of Plant Pathology, University of Agricultural Sciences, Bengaluru, Karnataka, India KB Palanna Project Coordinating Unit, ICAR-AICRP on Small Millets, University of Agricultural Sciences, GKVK, Bengaluru, Karnataka, India Arunkumar Department of Plant Pathology, University of Agricultural Sciences, Bengaluru, Karnataka, India Ravichandra Department of Plant Pathology, University of Agricultural Sciences, Bengaluru, Karnataka, India Bharath M Department of Plant Pathology, University of Agricultural Sciences, Bengaluru, Karnataka, India Prabhu C Ganiger Project Coordinating Unit, ICAR-AICRP on Small Millets, University of Agricultural Sciences, GKVK, Bengaluru, Karnataka, India Corresponding Author: Gutha Venkata Ramesh Department of Plant Pathology, University of Agricultural Sciences, Bengaluru, Karnataka, India Comparative evaluation of different media and pH for the culturing of Bipolaris setariae causing leaf blight in browntop millet in India Gutha Venkata Ramesh, KB Palanna, Arunkumar, Ravichandra, Bharath M and Prabhu C Ganiger DOI: https://doi.org/10.22271/j.ento.2021.v9.i1ac.8433 Abstract Browntop millet was newly included in the millet cropping system in India as one of the small millet. Incidence of leaf blight was observed to be severe in all millet growing regions of India and the causal organism was confirmed as B. setariae using molecular tools viz., ITS and GPDH genes. As the crop was newly included in the millet system, investigation was needed to carry out about disease causing agents their biology and culture conditions. In this study, an attempt was made to identify the ideal culturing and physiological requirements for culturing B. setariae. Results revealed that solid media such as Czapek Dox agar (CDA) and host leaf decoction agar with 2 per cent sucrose are ideal for better growth and abundant sporulation while, pH 6.0 to pH 7.0 were found to be ideal for radial mycelial growth and sporulation. These cultural and physiological conditions can be used for the future studies while working on the pathogen causing browntop millet leaf blight. Keywords: browntop millet, B. setariae, In vitro, media, Czapek Dox agar and pH 1. Introduction Millets have been superior to commercially growing cereal crops since ancient times not in terms of quantity that they produce but in terms of quality that they possess. With their importance and considering on going climate changes, FAO approved and declared 2023 as the International year of millets whereas, India celebrated 2018 as the National year of millets. Small millets are one of the crops that are negligible in production but are highly nutritious and also possess features like drought tolerance, high mineral and vitamin content. Browntop millet [Brachiaria ramosa (L.) Stapf] native to India and was recently included into millets system in India as one of the small millet for commercial cultivation. It is different from other small millets by having characters like short growth period, shade tolerant, suppress root knot nematode and because of their sharp and stiff leaf structure it obstructs the entry of rats in to fields. In India, it is majorly cultivated in dry tracts of Andhra Pradesh-Karnataka border areas, Tamil Nadu and Maharashtra (Sujata et al., 2018) [1] . Among the various biotic constraints, diseases caused by fungal pathogens are wide spread and destructive. Fungal disease recorded on small millets includes blast, leaf blight/brown spot, smut, downy mildew, leaf spot etc., among all the diseases brown spot or leaf blight disease caused by Helminthosporium sp. is gaining importance next only to blast in different parts of India. Misra and Prakash (1972) [11] first observed association of H. setariae with leaf spot of browntop millet. But there are no systemic studies were carried out on pathogen infecting browntop millet. The Present study concentrated on the culturing aspects of B. setariae to find ideal media and pH for better growth and sporulation which is useful for future studies on various aspects of the pathogen. 2. Material and Methods 2.1 Effect of different media The study was conducted to identify ideal medium and to describe the cultural characteristics viz., colour, type of margin, surface, topography, pigmentation, texture and sporulation of the pathogen and morphological characteristics of hyphal, conidiophore and conidia on different solid media. 5 mm culture discs of the pathogen were inoculated separately on different media