High-Throughput Sequencing of Virus-infected Cucurbita pepo Samples Revealed The Presence of Zucchini Shoestring Virus in Zimbabwe

Objectives: Plant-infecting viruses remain a serious challenge towards achieving food security worldwide. Cucurbit virus surveys were conducted in Zimbabwe during the 2014 and 2015 growing seasons. Leaf samples displaying virus-like symptoms were collected and stored until analysis. Three baby marrow samples were subjected to next-generation sequencing and the data generated were analysed using genomics technologies. Zucchini shoestring virus (ZSSV), a cucurbit-infecting potyvirus previously described in South Africa was one of the viruses identified. The genomes of the three ZSSV isolates are described analysed in this note. Results: The three ZSSV isolates had the same genome size of 10297 bp excluding the polyA tail with a 43% GC content. The large open reading frame was found at positions 69 to 10106 on the genome and encodes a 3345 amino acids long polyprotein which had the same cleavage site sequences as those described on the South African isolate except for the P1-pro site. Genome sequence comparisons of all the ZSSV isolates showed that the isolates F7-Art and S6-Prime had identical sequence across the entire genome while sharing 99.06% and 99.34% polyprotein nucleotide and amino acid sequence identities respectively with the isolate S7-Prime.

High-Throughput Sequencing of Virus-infected Cucurbita pepo Samples Revealed The Presence of Zucchini Shoestring Virus in Zimbabwe

Objectives: Plant-infecting viruses remain a serious challenge towards achieving food security worldwide. Cucurbit virus surveys were conducted in Zimbabwe during the 2014 and 2015 growing seasons. Leaf samples displaying virus-like symptoms were collected and stored until analysis. Three baby marrow samples were subjected to next-generation sequencing and the data generated were analysed using genomics technologies. Zucchini shoestring virus (ZSSV), a cucurbit-infecting potyvirus previously described in South Africa was one of the viruses identified. The genomes of the three ZSSV isolates are described analysed in this note. Results: The three ZSSV isolates had the same genome size of 10297 bp excluding the polyA tail with a 43% GC content. The large open reading frame was found at positions 69 to 10106 on the genome and encodes a 3345 amino acids long polyprotein which had the same cleavage site sequences as those described on the South African isolate except for the P1-pro site. Genome sequence comparisons of all the ZSSV isolates showed that the isolates F7-Art and S6-Prime had identical sequence across the entire genome while sharing 99.06% and 99.34% polyprotein nucleotide and amino acid sequence identities respectively with the isolate S7-Prime.

Description of a new subspecies of Bursaphelenchus africanus (Nematoda: Aphelenchoididae) found in packaging wood from Russia

Bursaphelenchus africanus rossicus subsp. n. was detected from Russian packaging wood (Pinus sp.) arriving in China in August, 2009. The spicule shape and size are almost the same as in the B. africanus found in wood from South Africa, but it differs slightly from the South African isolate by longer (mean L=945 vs 691 μm and 1062 vs 766 μm, for males and females, respectively) and slimmer body (a=39.8 vs 35.0 and 40.0 vs 35.1, for males and females, respectively), higher male ratio c (mean c=37.0 vs 28.7) and higher female ratio c′ (mean c′=4.7 vs 3.4), longer female tail (58 vs 42 μm), and also by female tail shape (slightly ventrally bent vs straight). Their ITS-RFLP patterns are also slightly different. Based on the absence of clear morphological differences and relatively small ITS1/2 and D2/D3 LSU sequence divergences, the new isolate is considered as Bursaphelenchus africanus rossicus subsp. n.