Influence of air temperature and relative humidity on biological control of white mold of bean (Sclerotinia sclerotiorum)
1996
Hannusch, D.J. | Boland, G.J.
The interactions of Sclerotinia sclerotiorum and seven biological control agents (BCAs) were examined in controlled environments to determine the influence of selected relative humidities (RH) (90, 95, and 100%) and air temperatures (20, 24, and 28 degrees C) on biological control of white mold of bean. All main effects and interactions were significant (P less than or equal to 0.0001) among the 72 treatments. In the control treatment, lesions of white mold developed in all environmental treatments but were largest at 20 degrees C X 100% RH, 24 degrees C X 95 and 100% RH, and 28 degrees C X 95% RH. Interactions of environment, BCAs, and white mold were highly complex. Alternaria alternata, Drechslera sp., Myrothecium verrucaria, Trichoderma viride, Gliocladium roseum, and an unidentified pink yeast were all highly dependent on environment for efficacy. Changes of 4 degrees C or 5% RH were associated with variability in disease suppression that ranged from less than or equal to 25 to 100%. Epicoccum nigrum was comparatively independent of environment and suppressed disease by 100% in all environments. Suppression of disease by many of the BCAs was most effective under environmental conditions that were least conducive for disease. Assessments of biological control efficacy in various environments can be used to more accurately assess the potential of individual BCAs.
显示更多 [+] 显示较少 [-]