Hwang J, Benson D M
Department of Plant Pathology, North Carolina State University, Raleigh 27695.
Plant Dis. 2005 Feb;89(2):185-190. doi: 10.1094/PD-89-0185.
Phytophthora isolates were collected from floriculture crops grown in commercial greenhouses in North Carolina for species identification, compatibility type determination, and mefenoxam sensitivity tests. Isolation from 41 symptomatic plant species at 29 production locations resulted in 483 isolates from eight crops at seven locations. Phytophthora cryptogea (184 isolates) was recovered from dusty miller and gerbera daisy. All isolates of P. cryptogea were insensitive or intermediate in sensitivity to mefenoxam at 1 μg a.i./ml and were A1 compatibility type. P. nicotianae (273 isolates) was isolated from African violet, lavender, pansy, petunia, and vinca. Of these isolates, 21% were insensitive to mefenoxam at either 1 or 100 μg a.i./ml. Isolates of P. nicotianae from five locations were A2 compatibility type, whereas isolates on pansy at one location were A1 compatibility type. English ivy grown at two locations was infected with P. palmivora. All 26 isolates of P. palmivora were sensitive to mefenoxam and were A1 compatibility type. Mating type and mefenoxam sensitivity were uniform among isolates of P. nicotianae and P. palmivora from a given crop at a given location, suggesting that epidemics within a location may have originated from a single source of inoculum.
从北卡罗来纳州商业温室种植的花卉作物中收集疫霉菌分离株，用于物种鉴定、交配型测定和甲霜灵敏感性测试。在29个生产地点对41种有症状的植物物种进行分离，从7个地点的8种作物中获得了483个分离株。从银叶菊和非洲菊中分离出隐地疫霉（184个分离株）。所有隐地疫霉分离株在1μg a.i./ml时对甲霜灵不敏感或敏感性中等，且为A1交配型。烟草疫霉（273个分离株）从非洲紫罗兰、薰衣草、三色堇、矮牵牛和长春花中分离得到。在这些分离株中，21%在1或100μg a.i./ml时对甲霜灵不敏感。来自5个地点的烟草疫霉分离株为A2交配型，而在一个地点的三色堇上的分离株为A1交配型。在两个地点种植的常春藤感染了棕榈疫霉。所有26个棕榈疫霉分离株对甲霜灵敏感，且为A1交配型。来自给定地点给定作物的烟草疫霉和棕榈疫霉分离株的交配型和甲霜灵敏感性一致，这表明一个地点内的疫情可能源于单一接种源。
