EMA, Centre LGEI, 6 Avenue de Clavières, 30319 Alès, France.
J Invertebr Pathol. 2012 Jul;110(3):375-81. doi: 10.1016/j.jip.2012.04.012. Epub 2012 May 1.
The Guatemalan potato moth Tecia solanivora (Povolny) recently invaded part of South America, colonizing zones where Phthorimaea operculella (Zeller), another potato moth species belonging to the same group, was previously established. T. solanivora is now the major insect pest of potato in this area encompassing Venezuela, Colombia and Ecuador. P. operculella granulovirus (PhopGV) (Betabaculovirus) is a biocontrol agent to be considered for the simultaneous management of these two potato pests, instead of classical chemical insecticides. In a previous work, five PhopGV isolates were isolated in Colombia from T. solanivora and were tested against larvae of the same species showing variable efficacies. Infections with mixtures of different genotypes of Baculoviruses had been carried out in a wide range of species and several showed interesting results. In the present study, the effect of sequential passages of PhopGV in P. operculella and T. solanivora larvae was analyzed through biological assays. Three different mixtures containing a Peruvian PhopGV isolate (Peru) adapted to P. operculella and a Colombian PhopGV isolate (VG003) adapted to T. solanivora were tested. A preliminary analysis of the correlation between the genotypic marker egt gene and the level of pathogenicity after a variable number of replication cycles was made. Mixtures of virus isolates showed a higher efficacy in both hosts compared to individual PhopGV isolates. This higher pathogenicity was maintained through passages. In P. operculella the mixtures were between 2.8 and 23.6-fold (from 7.15 OB/mm(2) to 0.10 OB/mm(2)) more pathogenic than isolate Peru applied alone. In T. solanivora they were between 2.3 and 4.9-fold (from 12.29 OB/mm(2) to 1.25 OB/mm(2)) more pathogenic than isolate VG003 alone. Viral biopesticide containing a mixture of selected genotypes active against each hosts seemed suitable for the development of a biopesticide aimed to simultaneously control P. operculella and T. solanivora.
危地马拉马铃薯块茎蛾（Tecia solanivora）（Povolny）最近入侵了南美洲的部分地区，在那里建立了另一种马铃薯蛾物种 Phthorimaea operculella（Zeller）（属于同一组）的殖民地。T. solanivora 现在是该地区（包括委内瑞拉、哥伦比亚和厄瓜多尔）马铃薯的主要害虫。PhopGV（Betabaculovirus）是一种生物防治剂，可考虑用于同时管理这两种马铃薯害虫，而不是使用传统的化学杀虫剂。在之前的工作中，在哥伦比亚从 T. solanivora 中分离出了五个 PhopGV 分离株，并对同一物种的幼虫进行了测试，显示出不同的功效。在多种物种中进行了不同基因型杆状病毒混合物的感染，并且取得了一些有趣的结果。在本研究中，通过生物测定分析了 PhopGV 在 P. operculella 和 T. solanivora 幼虫中的连续传代的效果。测试了三种含有秘鲁 PhopGV 分离株（秘鲁）适应 P. operculella 和哥伦比亚 PhopGV 分离株（VG003）适应 T. solanivora 的不同混合物。对基因标记 egt 基因与复制循环数后致病性水平之间的相关性进行了初步分析。与单独使用 PhopGV 分离株相比，病毒分离株混合物在两种宿主中的功效更高。这种更高的致病性通过传代得以维持。在 P. operculella 中，混合物比单独使用秘鲁分离株的毒性高 2.8 到 23.6 倍（从 7.15 OB/mm(2) 到 0.10 OB/mm(2)）。在 T. solanivora 中，它们比单独使用 VG003 分离株的毒性高 2.3 到 4.9 倍（从 12.29 OB/mm(2) 到 1.25 OB/mm(2)）。含有针对每种宿主的活性选择基因型混合物的病毒生物农药似乎适合开发一种旨在同时控制 P. operculella 和 T. solanivora 的生物农药。
