First report of Cassava brown streak viruses on wild plant species in Mozambique. (January 2019)

• Record Type: Journal Article
• Authors: Amisse, Jamisse J.G.; Ndunguru, Joseph; Tairo, Fred; Boykin, Laura M.; Kehoe, Monica A.; Cossa, Nurbibi; Ateka, Elijah; Rey, Chrissie; Sseruwagi, Peter
• Is Part Of: Physiological and molecular plant pathology. Volume 105(2019)
• Page Start: 88
• Page End: 95
• Publication Date: 2019-01
• Subjects: Cassava brown streak viruses -- Wild host plants -- Mechanical inoculation -- Alternative host -- Mozambique; Plant diseases -- Periodicals; Diseased plants -- Physiology -- Periodicals; Phytopathogenic microorganisms -- Host plants -- Periodicals; 632
• DOI: 10.1016/j.pmpp.2018.10.005
• Languages: English
• ISSNs: 0885-5765

Abstract

Abstract: Cassava brown streak disease (CBSD) caused by Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV) is the main constraint to cassava ( Manihot esculenta Crantz) production in Mozambique. Using RT-PCR to amplify partial coat protein nucleotide sequences, we detected for the first time the occurrence of CBSV in two non-cassava perennial wild plant species: Zanha africana ( Radlk. ) Exell. and Trichodesma zeylanicum (Burm.f.) R.Br ., that occur widely within and near cassava fields in Nampula, Zambezia, Niassa and Cabo Delgado provinces. In addition, we also detected CBSV and UCBSV in Manihot carthaginensis subsp . glaziovii (Müell-Arg.) Allem., a wild cassava relative. These findings were verified in biological assays through mechanical inoculation of CBSV to T. zeylanicum, albeit at low rates of infection. Phylogenetic analysis clustered the CBSV isolates from the non-cassava plant species with those from cultivated cassava, with high sequence homology among CBSV (91.0–99.6%) and with UCBSV (84–92%) isolates. These results provide definitive evidence of a wider host range for CBSV and UCBSV in Mozambique, indicating that these viruses are not restricted to cultivated cassava. Our findings are key to understanding the epidemiology of CBSD and will aid in the development of sustainable management strategies for the disease. Highlights: Alternative host plants of Cassava brown streak viruses were determined. There was evidence of natural infection of CBSV in non-cassava relative plants. CBSV was successfully transmitted in T. zeylanicum by mechanical inoculation. CBSV and UCBSV, associated with CBSD in cassava, naturally infect M. glaziovii .