Phylogenetic Analysis of Two Ukrainian Isolates of Cucumber Mosaic Virus From Gladioli Grown Under Different Agroecological Conditions

Abstract

Cucumber mosaic virus (CMV) is one of the most widespread and harmful viruses infecting gladiolus plants worldwide. The aim of the study was to perform a phylogenetic analysis of two CMV isolates from gladioli grown in different regions of Ukraine. For the first time, 443 nt sequences of the capsid protein (CP) gene of gladiolus isolates CMV-Gl-Skv-20 (MW847710) and CMV-Gl-SkvP-20 (MW847714) from Kyiv and Poltava regions, respectively, were submitted to the NCBI GeneBank. Phylogenetic analysis showed that isolates clustered with different phylogenetic subgroups. CMV-Gl-Skv-20 belongs to subgroup IA, and has nucleotide (nt) sequence identity 81.9%-99.27% and amino acid (aa) identity 82.3%-97.6% with isolates from this group. The highest identity of the CMV-Gl-Skv-20 was found to be with Turkish CMVs from Rapistrum rugosum TUR83, TUR86 and Brassica TUR4 (98.8%-99.3% nt and 97,6% aa), as well as with Australian isolates Ny and 207 from tomato, and banana isolate Cameroon (98.9%-99% nt and 97,6% aa). CMV-Gl-SkvP-20 belongs to subgroup IB and shares 95.8%-100% nt and 96%-100% aa identity with the members of this subgroup. CMV-Gl-SkvP-20 has the highest identity with Ukrainian isolates from cucumber Ukr-1409 and Echinacea P-EP-Ukr-19 (99.5%-100% nt and 99.2-100% aa), Chinese pumpkin isolates ZBR, WHR, isolate lu-17-14 from sweet potato and SXCH from Bupleurum sp. (98.3-99% nt and 98.4%-99.2% aa), as well as with gladiolus South Korean isolate ABI (98.3% nt and 97.7% aa). The results support the fact that gladioli are affected by CMV not only through the corms, but by vector insects circulating in growing areas.