Phytopathologia Mediterranea 60(3): 409-419, 2021 Firenze University Press www.fupress.com/pm ISSN 0031-9465 (print) | ISSN 1593-2095 (online) | DOI: 10.36253/phyto-12745 Phytopathologia Mediterranea The international journal of the Mediterranean Phytopathological Union Citation: M. Ansar, A.K. Agnihotri, T. Ranjan, M. Karn, Srinivasaraghavan A, R.R. Kumar, A.P. Bhagat (2021) Night- shade (Solanum nigrum), an intermedi- ate host between tomato and cucurbits of Tomato leaf curl New Delhi virus. Phytopathologia Mediterranea 60(3): 409-419. doi: 10.36253/phyto-12745 Accepted: July 13, 2021 Published: November 15, 2021 Copyright: © 2021 M. Ansar, A.K. Agni- hotri, T. Ranjan, M. Karn, Srinivasara- ghavan A, R.R. Kumar, A.P. Bhagat. This is an open access, peer-reviewed article published by Firenze Univer- sity Press (http://www.fupress.com/pm) and distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distri- bution, and reproduction in any medi- um, provided the original author and source are credited. Data Availability Statement: All rel- evant data are within the paper and its Supporting Information fles. Competing Interests: The Author(s) declare(s) no confict of interest. Editor: Assunta Bertaccini, Alma Mater Studiorum, University of Bologna, Italy. Research Papers Nightshade (Solanum nigrum), an intermediate host between tomato and cucurbits of Tomato leaf curl New Delhi virus Mohammad ANSAR 1, *, Aniruddha Kumar AGNIHOTRI 2 , Tushar RANJAN 3 , Monika KARN 4 , Srinivasaraghavan A 1 , Ravi Ranjan KUMAR 3 , Arun Prasad BHAGAT 1 1 Department of Plant Pathology, Bihar Agricultural University, Sabour-813 210, Bhagal- pur, Bihar, India 2 Division of Crop Protection, Indian Institute of Pulses Research, Kanpur-208 024, U.P., India 3 Department of Molecular Biology and Genetic Engineering, Bihar Agricultural Univer- sity, Sabour-813 210 Bhagalpur, Bihar, India 4 Department of Plant Pathology, Dr. Y S Parmar University of Horticulture and Forestry, Nauni Solan-173 230, Himanchal Pradesh, India *Corresponding author. E-mail: ansar.pantversity@gmail.com Summary. Geminiviruses infect many crop plants, and are limiting factors for veg- etable crop production. Begomoviruses (Geminiviridae) cause typical symptoms of leaf curling and puckering in nightshade (Solanum nigrum), a seasonal weed in Bihar, India. To investigate if nightshade was an intermediate host for begomo- virus, virus DNA was extracted and characterized. Te DNA-A of the virus yielded 2737 nt and DNA-B yielded 2706 nt. Te intergenic region (IR) showed a conserved nonanucleotide sequence that potentially forms a stem-loop structure. Te genomic sequence of DNA-A shared 94% identity with that of Tomato leaf curl New Delhi virus (ToLCNDV)-ivy gourd isolate. However, the sequence of DNA-B showed 95% identity with a bitter gourd isolate. PCR-based detection revealed the presence ToLCNDV in bottle gourd, pumpkin, sponge gourd, and bitter gourd. Te IR sequences of the virus- es isolated from these cucurbits and tomato were 100% identical. Whitefy-mediated transmission of the virus to cucurbits and tomato from nightshade was also demon- strated. Tese results indicate that nightshade may act as reservoir of ToLCNDV, and is involved in developing epidemics in cucurbit species. Te strain of ToLCNDV has probably adapted from solanaceous to cucurbitaceous hosts. Tis is the first report of ToLCNDV infecting nightshade in India, highlighting this virus as a possible cause of disease epidemics in economically important cucurbits. Keywords. Begomovirus, genetic diversity, leaf curl. INTRODUCTION Weed plants possess ecological adaptability, and are found throughout the world. Tey are sources and reservoirs of viruses infecting many economically