title: [Relationship between root rot on Panax notoginseng Burk. F. H. Chen and its environmental conditions].
abstract: OBJECTIVE
  To probe into the relationship between root rot on Panax notoginseng and its environmental conditions for integrate control of the disease.
  
  
  METHODS
  Field observation and analysis on the planting plots were conducted regularly.
  
  
  RESULTS
  Root rot on P. notoginseng occurs extensively in Wenshan Prefecture, with two peaks of incidence per year. The first peak appears in March-April; and the second July-August. Air temperatures around 20 degrees C and relative humidities of higher than 95% are favorable for the disease to occur and spread. The root rot is severe when the light transmitting rate in the shade shed is too high(> 30%). The disease is severer in land of continuous cropping than in land of rotational cropping and land of new cropping. The severity of the rot increases with the years of continuous cropping. The art of field management also influences the occurring and spreading of the disease.
  
  
  CONCLUSIONS
  The occurring and spreading of P. notoginseng root rot are closely related to its environmental conditions.
authors.affiliation: Wenshan Research Institute of Sanqi Science and Technology, Wenshen 663000.
authors.forename: C
authors.initials: C
authors.lastname: Wang
authors.forename: X
authors.initials: X
authors.lastname: Cui
authors.forename: Z
authors.initials: Z
authors.lastname: Li
authors.forename: C
authors.initials: C
authors.lastname: He
authors.forename: S
authors.initials: S
authors.lastname: Yu
authors.forename: W
authors.initials: W
authors.lastname: Luo
mesh_terms: D004365:Drugs, Chinese Herbal; D004463:Ecology; D005308:Fertilizers; D006813:Humidity; D008027:Light; D005894:Panax / Q000254:growth & development*; D010935:Plant Diseases / Q000209:etiology*; D013696:Temperature
chemical_list: D004365:Drugs, Chinese Herbal; D005308:Fertilizers