Molecular characterization and cytopathological studies of olive latent virus 1 (olv-1) and olive latent virus 2 (olv-2) isolated from olive trees in Egypt

In a preliminary study for the assessment of the sanitary status of olive trees in Egypt during April and May in the two successive season 2014-2015. Three hundred shoots were collected from symptomatic and asymptomatic ten olive cultivars from three different locations in Egypt i.e., Siwa, Marsa Matrouh and Beheira. RNA was extracted and used directly for one step RT-PCR with specific primer for each virus. Electron microscopy of sap extracts from olive infected leaves with the two viruses most commonly found Olive Latent Virus-1 (OLV-1) and Olive Latent Virus-2 (OLV-2) showed isometric particles consistent to Necrovirus (OLV-1) and bacilliform particles consistent to Oleavirus (OLV-2). Ultrastructure changes in inoculated Chenopodium amaranticolor and Chenopodium quinoa showed necrolization and vaculation of the cytoplasm, layside and degenerated of chloroplast membrane, deformation of chloroplast, tubular like structural, crossing the all wall and deformation and lysis of the nucleus. Nucleotide sequencing analysis for 230bp amplified fragment from the coat protein gene of OLV-1 and 222bp amplified fragment from the coat protein gene of OLV-2 showed homology ranged from 98% to 94 % with Italy and Poland Isolates for OLV-1 and 98 % to 94 % with USA and Italy for OLV-2. Based on molecular studies and cytopathological, viruses under study were identified as an isolates of OLV-1 and OLV-2.