title: Conjunctively screening of biocontrol agents (BCAs) against fusarium root rot and fusarium head blight caused by Fusarium graminearum.
abstract: OBJECTIVE
  Fusarium root-rot and fusarium head blight are plant diseases caused by Fusarium sp. in different growth periods of wheat, bring heavy losses to crop production in China. This research is aiming to screen biocontrol agents conjunctively for controlling these two diseases at the same time, as well as evaluate our previous BCAs (Biological Control Agents) screening strategies in more complex situation, considering biocontrol is well concerned as an environmental-friendly plant disease controlling method.
  
  
  METHODS
  Totally 966 bacterial isolates were screened from different parts of wheat tissues, of which potential biocontrol values were detected according to their abilities in antagonism inhibition and secreting extracellular hydrolytic enzyme. Biocontrol tests against fusarium root rot and fusarium head blight were carried out on 37 bacterial isolates with potential biocontrol capacity after pre-selection through ARDRA- and BOX-PCR analysis on strains with high assessment points.
  
  
  RESULTS
  We acquired 10 BCAs with obvious biocontrol efficacy (more than 40%) in greenhouse and field tests. Pseudomonas fluorescens LY1-8 performed well in both two tests (biocontrol efficacy: 44.62% and 58.31%), respectively. Overall, correlation coefficient is 0.720 between assessment values of 37 tested BCA strains and their biocontrol efficacy in trails against fusarium root rot; correlation coefficient is 0.806 between their assessment values and biocontrol efficacy in trails against fusarium head blight.
  
  
  CONCLUSIONS
  We acquired 10 well-performed potential BCAs, especially P. fluorescens LY1-8 displayed good biocontrol capacity against two different diseases on wheat. Biocontrol efficacies results in both greenhouse and field tests showed high positive correlation with assessment values (0.720 and 0.806), suggesting that the BCAs screening and assessing strategy previously developed in our lab is also adaptable for conjunctively screening BCAs for controlling both root and shoot diseases on wheat caused by same fungal pathogen.
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Engineering Center of Bioresource Pesticide in Jiangsu Province, Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Agriculture, Nanjing 210095, China.
authors.forename: Lu-Yao
authors.initials: LY
authors.lastname: Wang
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Engineering Center of Bioresource Pesticide in Jiangsu Province, Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Agriculture, Nanjing 210095, China.
authors.forename: Yue-Shen
authors.initials: YS
authors.lastname: Xie
authors.affiliation: Plant Protection Institution, Xinjiang Agricultural Science Academy, No. 403 in Nanchang Road, Urumqi 830091, China.
authors.forename: Yuan-Yu
authors.initials: YY
authors.lastname: Cui
authors.affiliation: Plant Protection Institution, Xinjiang Agricultural Science Academy, No. 403 in Nanchang Road, Urumqi 830091, China.
authors.forename: Jianjun
authors.initials: J
authors.lastname: Xu
authors.affiliation: Plant Protection Institution, Xinjiang Agricultural Science Academy, No. 403 in Nanchang Road, Urumqi 830091, China.
authors.forename: Wei
authors.initials: W
authors.lastname: He
authors.affiliation: Institute of Plant Protection, Academy of Agricultural Sciences, Nanjing, Jiangsu Province, China.
authors.forename: Huai-Gu
authors.initials: HG
authors.lastname: Chen
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Engineering Center of Bioresource Pesticide in Jiangsu Province, Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Agriculture, Nanjing 210095, China. Electronic address: jhguo@njau.edu.cn.
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Guo
mesh_terms: D000898:Antibiosis; D001419:Bacteria / Q000254:growth & development* / Q000302:isolation & purification / Q000378:metabolism; D002681:China; D005670:Fusarium / Q000187:drug effects* / Q000254:growth & development; D008403:Mass Screening / Q000379:methods*; D010935:Plant Diseases / Q000517:prevention & control*; D018517:Plant Roots / Q000382:microbiology; D014908:Triticum / Q000382:microbiology*
keywords: Biocontrol agent; Biocontrol efficacy; Fusarium head blight; Fusarium root rot