Department of Plant Pathology, Oklahoma State University, Stillwater, Oklahoma 74078; Research and Extension Center, Texas A&M University, Dallas, Texas 75252 ; and 230 W. Okmulgee Street, Muskogee, Oklahoma 74401.
Appl Environ Microbiol. 1990 Jan;56(1):170-5. doi: 10.1128/aem.56.1.170-175.1990.
The efficacy of copper bactericides for control of Xanthomonas campestris pv. vesicatoria in eastern Oklahoma tomato fields was evaluated. Copper bactericides did not provide adequate control, and copper-resistant (Cu) strains of the pathogen were isolated. The Cu genes in these strains were located on a large indigenous plasmid designated pXV10A. The host range of pXV10A was investigated; this plasmid was efficiently transferred into 8 of 11 X. campestris pathovars. However, the transfer of pXV10A to other phytopathogenic genera was not detected. DNA hybridization experiments were performed to characterize the Cu genes on pXV10A. A probe containing subcloned Cu genes from X. campestris pv. vesicatoria E3C5 hybridized to pXV10A; however, a subclone containing Cu genes from P. syringae pv. tomato PT23 failed to hybridize to pXV10A. Further DNA hybridization experiments were performed to compare pXV10A with pXvCu plasmids, a heterogenous group of Cu plasmids present in strains of X. campestris pv. vesicatoria from Florida. These studies indicated that the Cu genes on pXV10A and pXvCu plasmids share nucleotide sequence homology and may have a common origin. Further experiments showed that these plasmids are distinctly different because pXV10A did not contain sequences homologous to IS476, an insertion sequence present on pXvCu plasmids.
在俄克拉荷马州东部的番茄田中评估了铜杀菌剂对野油菜黄单胞菌 pv.vesicatoria 的防治效果。铜杀菌剂不能提供充分的控制，并且分离出了病原体的铜抗性（Cu）菌株。这些菌株中的 Cu 基因位于一个被命名为 pXV10A 的大型本土质粒上。研究了 pXV10A 的宿主范围；该质粒有效地转移到了 11 个野油菜黄单胞菌致病变种中的 8 个中。然而，未检测到 pXV10A 向其他植物病原性属的转移。进行了 DNA 杂交实验以表征 pXV10A 上的 Cu 基因。包含来自野油菜黄单胞菌 pv.vesicatoria E3C5 的亚克隆 Cu 基因的探针与 pXV10A 杂交；然而，包含来自 P. syringae pv. tomato PT23 的 Cu 基因的亚克隆未能与 pXV10A 杂交。进一步的 DNA 杂交实验用于比较 pXV10A 与 pXvCu 质粒，pXvCu 质粒是存在于佛罗里达州野油菜黄单胞菌 pv.vesicatoria 菌株中的一组异质 Cu 质粒。这些研究表明，pXV10A 和 pXvCu 质粒上的 Cu 基因具有核苷酸序列同源性，可能具有共同的起源。进一步的实验表明，这些质粒明显不同，因为 pXV10A 不包含存在于 pXvCu 质粒上的插入序列 IS476 的同源序列。
