01921nam a2200133 a 450000100080000000500110000800800410001910000220006024500860008226000160016850000640018452015190024865000200176719370452012-10-17       1997    bl uuuu  m   00u1 u    #d1 aDIANESE, A. de C.  aImportance of nutritional similarity in pre-emptive biocontrol of bacterial spot.  a1997.c1997  aThesi (Master of Science)- Auburn University, Auburn, 1997.  aIt was hypothesized that the effectiveness of a nonpathogenic epiphytic bacterium as a pre-emptive biocontrol agent of an epiphytic phytopathogenic bacterium should be related to the nutritional similarity between the nonpathogenic bacterium and the target pathogen. This was investigated using X. Axonopodis pv.vesicatoria  on tomato.Two parameters were used to quantify pre-emptive: biocontrol effectiveness:  disease severity (lesions/cm², and pathogen population size on the leaf ( CFU/leaf). Pre-emptive biocontrol effectiveness was quantified as mean percent disease and population reduction in greenhouse and growth chamber assays, respectively, in which 34 nonpathogenic epiphytes (10 CFU/ ml) were each inoculated individually 48 -H in advance of the pathogen X. ª pv. Vesicatoria strain AD17 rif3 (10 CFU/ml ? greenhouse; 10¨CFU/ml ? growth camber) onto tomato plants (cv. Agriset 761). Nutritional similarity between the nonpathogenic epiphytic bacteria and prototrophic X.  pv. Vesicatoria strain AD17rif3 was quantified using a niche overlap indices (NOI), and relatedness ( Euclidian Distance or Coefficient of similarity) in cluster analyses, based upon in vitro  carbon and nitrogen sources reported to be present in tomato, and Biolog GN nutritional profiles. There was no correlation between preemptive biocontrol effectiveness, quantified using reduction in disease severity and in pathogen population size, and nutritional similarity, based on carbon or nitrogen source utilization profiles.  aplant pathology