The efficacy of Tilletiopsis pallescens, formulated with natural oils on the inhibition of cucumber powdery mildew in greenhouses was investigated. Two foliar sprays of cotton, maize, sunflower or paraffin oil formulations (0.05 %) of T. pallescens were sprayed on cucumber plants, 30 and 75 days after planting. The oils formulated with T. pallescens improved the biocontrol potential. The most effective treatments were cotton, paraffin and maize oil formulations which enhanced the T. pallescens survival and the plant protection against the powdery mildew disease incidence. Where, the disease colonies, disease severity and infected leaf areas as well as Sphaerotheca fuliginea sporulation were greatly suppressed. Furthermore, cotton oil formulation of Tilletiopsis isolate exhibited high quantities of chitinase , β-1,3- glucanase, cellulase and protease isozyme bands of cucumber leaves surface after 10 extended to 40 days of application. On the contrast, unamended oil treatments showed moderate isozyme bands activity after 10 days of application and then began to decline after 40 days of application. Whereas no β-1,3- glucanase or cellulase were detected. At the same time, yield of cucumber plants treated with oil formulations of T. pallescens was significantly higher.
Wafaa M. Haggag and Nadia G. El-Gamal , 2001. Efficiency of the Antagonist Tilletiopsis pallescens Formulated with Some Natural Oils for Biocontrol of the Powdery Mildew in Greenhouse Cucumber . Pakistan Journal of Biological Sciences, 4: 1244-1250.