title: [Studies on initial infection sources and channels of black spot on Panax notoginseng (Burk.) F.H. Chen].
abstract: OBJECTIVE
  To probe into the occurring and developing regularities of black spot on Panax notoginseng for disease control.
  
  
  METHODS
  After artificial inoculation, observation and analysis on the planting plots were conducted regularly.
  
  
  RESULTS
  The main infection sources include diseased seeds, seedlings, plants and soils. On the plot of new cropping, the initial infection sources are diseased seeds and seedlings while diseased plants and soils with pathogens are the main sources onplot of old cropping.
  
  
  CONCLUSIONS
  Wiping out the infection centre and sources are the major effective means for control of black spot on P. notoginseng.
authors.affiliation: Wenshan Research Institute of Sanqi Science and Technology, Wenshan 663000, Yunnau, China.
authors.forename: C L
authors.initials: CL
authors.lastname: Wang
authors.forename: X M
authors.initials: XM
authors.lastname: Cui
authors.forename: W F
authors.initials: WF
authors.lastname: Luo
authors.forename: S F
authors.initials: SF
authors.lastname: Yu
mesh_terms: D005894:Panax / Q000254:growth & development / Q000382:microbiology*; D010935:Plant Diseases / Q000382:microbiology*; D010946:Plants, Medicinal / Q000254:growth & development / Q000382:microbiology*