Antagonistic mechanism of Pseudomonas fluorescens strains against Phytophthora nicotianae and biocontrol effect on tobacco black shank Control effectiveness and mechanism of chitinooligosaccharide on tobacco black shank Effects of the fermentation broth of Pythium oligandrum on the growth and black shank control of flue-cured tobacco Mapping of quantitative trait loci affecting resistance to black shank in tobacco line Beinhart1000-1 The role of salicylic acid and ethylene in resistance of tobacco to black shank Microbe quantity and functional diversity in rhizospheres of different cultivars of flue-cured tobacco Effect of nitrogen application rate on physiology of flue-cured tobacco plants with or without inoculation of Phytophthora parasitica var. nicotianae and the severity of black shank Effect of Increasing K Application Rate on Partial Physiological & Biochemical Parameters and Occurrence of Black Shank and Black Root Rot in Tobacco Variety Hongda