Effects of inoculum density, wetness duration, and temperature on control ofBotrytis cinereabyGliocladium roseumin raspberry

摘要

Control ofBotrytis cinereabyGliocladium roseumwas investigated in detached raspberry shoots maintained in high humidity. Sporulation incidence ofB. cinereain leaf disks, stem segments, stamens, and pistils respectively from shoots inoculated with 103, 104. 105, and 106conidia of the pathogen mL-1increased from 13 to 100, 7 to 100, 38 to 100, and 6 to 94. When shoots were challenge-inoculated after 24 h with 104to 108conidia ofG. roseummL-1, in all combinations, sporulation of the pathogen was suppressed completely in leaves, and by 97 in stems when density of the antagonist was 107conidia mL-1. Sporulation of the pathogen in stamens and pistils was suppressed more effectively when density of the antagonist was proportionately high.G. roseumdeveloped more extensively in leaves and stamens when postinoculation wetness lasted at least 12 to 24 h at 20 to 30#xB0;C, and controlled sporulation ofB. cinereamore effectively when conditions allowed the antagonist to establish endophytically. Polynomial regression models adequately described development ofG. roseumon raspberry as a function of wetness duration and temperature, and control ofB. cinereaas a function of wetness period and temperature, and of inoculum density ofG. roseumandB. cinerea. The observations have application in optimizing biological control ofB. cinereain raspberry.