Survey and Genetic Diversity of Grapevine Leafroll Associated Virus 2 in Algeria

Abstract

Vineyards in western and center regions of Algeria were surveyed for the Grapevine leafroll-associated virus 2 (GLRaV-2). Analyses by DAS-ELISA and Reverse Transcription Polymerase Chain Reaction (RT-PCR) reveal 15, 8% prevalence. The genetic diversity of the GLRaV-2 population was studied by phylogenetic analyses of the HSP70h gene region of seven samples sequenced in this study and other sequences downloaded from GenBank. Results reveal segregation of the GLRav-2 population into six distinct groups. An estimation of the ratio of non-synonymous substitutions per non-synonymous site to synonymous substitutions per synonymous site indicated that HSP70h gene evolve under positive selection. Similarity plot constructed with representative sequence from each group confirmed previous results. All Algerian isolates belong to group PN. As far as we know, this is the first characterization of GLRaV-2 isolates from Algeria.

Survey and Diversity of Grapevine Pinot gris virus in Algeria and Comprehensive High-Throughput Small RNA Sequencing Analysis of Two Isolates from Vitis vinifera cv. Sabel Revealing High Viral Diversity

“…In this study, we detected GLRaV-2 and GLRaV-3 in agreement with the studies of Lehad et al [ 21 , 22 ]. According to high-throughput small RNA sequencing, GLRaV-1 should be present; however, RT-PCR revealed that the samples were not clearly positive, and detection of GLRaV-1 alone in AL_41 did not clearly identify the PCR product [ 33 ] that could not be clearly established as virus positive.…”

“…The survey of GPGV was performed according to the observed symptoms in 54 grapevines in five Algerian regions. In Algeria, there is no clear evidence of the presence of grapevine viruses in the vineyards, except for the surveys of GLRaV-1 [ 20 ], GLRaV-2 [ 21 ] and GLRaV-3 [ 22 ].…”

“…Lehad et al [ 20 ] reported that GLRaV-1 was present in 5.4% of 484 grapevines in Algeria. GLRaV-2 was detected by Lehad et al [ 21 ] in 15.8% of Algerian vineyards, with 584 samples tested. GLRaV-3 was surveyed by Lehad et al [ 22 ] and was detected in 44% of 484 samples.…”

“…GLRaV-2 was detected by Lehad et al [ 21 ] in 15.8% of Algerian vineyards, with 584 samples tested. GLRaV-3 was surveyed by Lehad et al [ 22 ] and was detected in 44% of 484 samples. Detection of these viruses of the GLRaV group was verified in two samples, AL_41 and AL_42, in the present study, in agreement with the surveys of Lehad et al [ 20 , 21 , 22 ], indicating that these viruses may be widespread in Algeria.…”

“…The grapevine virome is not well described in Algeria. There have been surveys of Grapevine leafroll-associated virus-1 [ 20 ], Grapevine leafroll-associated virus-2 [ 21 ] and Grapevine leafroll-associated virus-3 [ 22 ]; however, a comprehensive virological study of grapevines has not been performed in Algerian vineyards. Therefore, we introduced high-throughput small RNA sequencing analysis as a tool for obtaining general and comprehensive information about viral diversity in selected grapevines.…”