Marquez-Villavicencio Maria Del Pilar, Groves Russell L, Charkowski Amy O
Department of Plant Pathology, University of Wisconsin-Madison, 1630 Linden Dr., Madison, WI 53706.
Department of Entomology, University of Wisconsin-Madison.
Plant Dis. 2011 Mar;95(3):232-241. doi: 10.1094/PDIS-07-10-0526.
Pectobacterium species cause disease worldwide in many crop and ornamental plants, including potato. A new Pectobacterium subspecies, P. carotovorum subsp. brasiliensis was recently described in Brazil and later found in the United States, Israel, and South Africa. Its virulence traits and host range remain unknown. A comparison of three taxa commonly found on potato showed that both P. carotovorum subsp. carotovorum and subsp. brasiliensis are more aggressive in causing tuber and stem soft rot than P. atrosepticum. Also, despite bacterial growth inhibition in vitro of P. carotovorum subsp. carotovorum and P. atrosepticum strains by P. carotovorum subsp. brasiliensis, this new subspecies and P. carotovorum subsp. carotovorum are able to co-colonize in the same infected tissue. Both subspecies were motile in lesions. Pathogenesis assays showed that host ranges of all three overlap, but are not identical. The host ranges of individual strains of P. carotovorum subsp. carotovorum and subsp. brasiliensis are limited, whereas P. atrosepticum can macerate many plant species in addition to potato. There was high variability in virulence assays with potato tuber; thus physiological factors were investigated. Tuber size, maturity, and field location had significant effects on susceptibility to soft rot, with larger, more mature tubers being more susceptible.
果胶杆菌属细菌在全球范围内对包括马铃薯在内的许多农作物和观赏植物都能致病。一种新的果胶杆菌亚种，即胡萝卜软腐果胶杆菌巴西亚种，最近在巴西被发现，随后在美国、以色列和南非也有发现。其致病特性和寄主范围尚不清楚。对马铃薯上常见的三个分类单元进行比较发现，胡萝卜软腐果胶杆菌胡萝卜亚种和巴西亚种在引起块茎和茎软腐方面比黑胫果胶杆菌更具侵染性。此外，尽管胡萝卜软腐果胶杆菌巴西亚种在体外对胡萝卜软腐果胶杆菌胡萝卜亚种和黑胫果胶杆菌菌株有细菌生长抑制作用，但这个新亚种和胡萝卜软腐果胶杆菌胡萝卜亚种能够在同一受感染组织中共存定殖。两个亚种在病斑中都具有运动性。致病性试验表明，这三个分类单元的寄主范围有重叠，但并不相同。胡萝卜软腐果胶杆菌胡萝卜亚种和巴西亚种的各个菌株的寄主范围有限，而黑胫果胶杆菌除了能侵染马铃薯外，还能使许多植物物种腐烂。在对马铃薯块茎进行的毒力试验中存在很大差异；因此对生理因素进行了研究。块茎大小、成熟度和田间位置对软腐易感性有显著影响，较大、较成熟的块茎更易感染。
