Kahn Noah D, Walgenbach J F, Kennedy G G
Department of Entomology, Box 7630, North Carolina State University, Raleigh, NC 27695-7630, USA.
J Econ Entomol. 2005 Dec;98(6):1810-5. doi: 10.1093/jee/98.6.1810.
In North Carolina, Tomato spotted wilt tospovirus (family Bunyaviridae, genus Tospovirus, TSWV) is vectored primarily by the tobacco thrips, Frankliniella fusca (Hinds), and the western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae). TSWV overwinters in winter annual weeds from which it is spread to susceptible crops in spring. Because most susceptible crops are destroyed after harvest before winter weeds emerge in the fall, infected summer weeds are thought to be the principal source for spread of TSWV to winter annual weeds in fall. A survey of summer weeds associated with TSWV-susceptible crops in the coastal plain of North Carolina conducted between May and October revealed that relatively few species were commonly infected with TSWV and supported populations of F. fusca or F. occidentalis. F. occidentalis made up > 75% of vector species collected from 15 summer weed species during 2002. The number of F. occidentalis and F. fusca immatures collected from plant samples varied significantly among plant species. Ipomoea purpurea (L.) Roth, Mollugo verticillata L., Cassia obtusifolia L., and Amaranthus palmeri S. Wats supported the largest numbers of immature F. occidentalis. Richardia scabra L., M. verticillata, and Ipomoea hederacea (L.) supported the largest numbers of F. fusca immatures. TSWV was present at 16 of 17 locations, and naturally occurring infections were found in 14 of 29 weed species tested. Five of the TSWV-infected species have not previously been reported as hosts of TSWV (A. palmeri, Solidago altissima L., Ipomoea lacunosa L., I. purpurea, and Phytolacca americana L.). Estimated rates of infection were highest in I. purpurea (6.8%), M. verticillata (5.3%), and I. hederacea (1.9%). When both the incidence of infection by TSWV and the populations of F. occidentalis and F. fusca associated with each weed species are considered, the following summer weed species have the potential to act as significant sources for spread of TSWV to winter annual weeds in fall: I. purpurea, I. hederacea, M. verticillata, A. palmeri, C. obtusifolia, R. scabra, Ambrosia artemisiifolia L., Polygonum pensylvanicum L., and Chenopodium album L.
在北卡罗来纳州，番茄斑萎病毒（布尼亚病毒科番茄斑萎病毒属，TSWV）主要由烟蓟马（Frankliniella fusca (Hinds)）和西花蓟马（Frankliniella occidentalis (Pergande)）（缨翅目：蓟马科）传播。TSWV在冬季一年生杂草中越冬，春季由此传播到易感作物上。由于大多数易感作物在收获后、秋季冬季杂草出现之前就被销毁，所以受感染的夏季杂草被认为是秋季TSWV传播到冬季一年生杂草的主要来源。在5月至10月期间对北卡罗来纳州沿海平原与TSWV易感作物相关的夏季杂草进行的一项调查显示，相对较少的物种普遍感染TSWV并支持烟蓟马或西花蓟马的种群。在2002年，从15种夏季杂草物种中采集的传毒昆虫中，西花蓟马占比超过75%。从植物样本中采集到的西花蓟马和烟蓟马未成熟个体数量在不同植物物种间差异显著。紫茉莉（Ipomoea purpurea (L.) Roth）、粟米草（Mollugo verticillata L.）、决明（Cassia obtusifolia L.）和糙果苋（Amaranthus palmeri S. Wats）上的西花蓟马未成熟个体数量最多。糙叶丰花草（Richardia scabra L.）、粟米草和裂叶牵牛（Ipomoea hederacea (L.)）上的烟蓟马未成熟个体数量最多。在17个地点中的16个检测到了TSWV，在测试的29种杂草中有14种发现了自然感染情况。5种感染TSWV的物种此前未被报道为TSWV的寄主（糙果苋、高一枝黄（Solidago altissima L.）、缺叶牵牛（Ipomoea lacunosa L.）、紫茉莉和美洲商陆（Phytolacca americana L.））。估计感染率在紫茉莉（6.8%）、粟米草（5.3%）和裂叶牵牛（1.9%）中最高。当同时考虑TSWV感染率以及与每种杂草物种相关的西花蓟马和烟蓟马种群数量时，以下夏季杂草物种有可能成为秋季TSWV传播到冬季一年生杂草的重要来源：紫茉莉、裂叶牵牛、粟米草、糙果苋、决明、糙叶丰花草、豚草（Ambrosia artemisiifolia L.）、宾夕法尼亚蓼（Polygonum pensylvanicum L.）和藜（Chenopodium album L.）。
