title: Studies on the Infection, Colonization, and Movement of Pseudomonas syringae pv. actinidiae in Kiwifruit Tissues Using a GFPuv-Labeled Strain.
abstract: Kiwifruit bacterial canker, an economically important disease caused by Pseudomonas syringae pv. actinidiae (Psa), has caused severe losses in all major areas of kiwifruit cultivation. Using a GFPuv-labeled strain of Psa, we monitored the invasion, colonization, and movement of the pathogen in kiwifruit twigs, leaves and veins. The pathogen can invade twigs through both wounds and natural openings; the highest number of Psa is obtained in cut tissues. We determined that, following spray inoculation, Psa-GFPuv could infect leaves and cause lesions in the presence and absence of wounds. Light and transmission electron microscopic observations showed that bacterial cells colonize both phloem and xylem vessels. Bacterial infection resulted in marked alterations of host tissues including the disintegration of organelles and degeneration of protoplasts and cell walls. Furthermore, low temperature was conducive to colonization and movement of Psa-GFPuv in kiwifruit tissues. Indeed, the pathogen migrated faster at 4°C than at 16°C or 25°C in twigs. However, the optimum temperature for colonization and movement of Psa in leaf veins was 16°C. Our results, revealing a better understanding of the Psa infection process, might contribute to develop more efficacious disease management strategies.
authors.affiliation: College of Plant Protection and State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, Shaanxi, P.R. China.
authors.forename: Xiaoning
authors.initials: X
authors.lastname: Gao
authors.affiliation: College of Plant Protection and State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, Shaanxi, P.R. China.
authors.forename: Qiling
authors.initials: Q
authors.lastname: Huang
authors.affiliation: College of Plant Protection and State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, Shaanxi, P.R. China.
authors.forename: Zhibo
authors.initials: Z
authors.lastname: Zhao
authors.affiliation: College of Plant Protection and State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, Shaanxi, P.R. China.
authors.forename: Qingmei
authors.initials: Q
authors.lastname: Han
authors.affiliation: College of Plant Protection and State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, Shaanxi, P.R. China.
authors.forename: Xiwang
authors.initials: X
authors.lastname: Ke
authors.affiliation: College of Plant Protection and State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, Shaanxi, P.R. China.
authors.forename: Huqiang
authors.initials: H
authors.lastname: Qin
authors.affiliation: College of Plant Protection and State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, Shaanxi, P.R. China.
authors.forename: Lili
authors.initials: L
authors.lastname: Huang
mesh_terms: D029042:Actinidia / Q000166:cytology / Q000382:microbiology* / Q000648:ultrastructure; D015169:Colony Count, Microbial; D005638:Fruit / Q000166:cytology / Q000382:microbiology* / Q000648:ultrastructure; D049452:Green Fluorescent Proteins / Q000378:metabolism*; D009068:Movement; D018515:Plant Leaves / Q000382:microbiology; D044224:Pseudomonas syringae / Q000254:growth & development*; D013696:Temperature
chemical_list: D049452:Green Fluorescent Proteins