The Determination of the Efficacy of some Microbial Preparations against Apple Scab Disease (Venturia Inaequalis (cke) Wint.) in Isparta

Abstract

The effect of Trichoderma harzianum (T-22), Bacillus subtilis (BS), mycorrhizal preparations (Endo Roots Soluble) and combinations was investigated against apple scap disease [Venturia inaequalis (Cke.) Wint.]. Biological preparations were applied as foliar and soil application in different combinations. The experiment was established in gardens with a Scarlet-Spur apple variety of 3 years old in Eg􀇍irdir. Biological preparations were applied at 3 times in April-May 2017, taking into account the warnings of the early warning system at the recommended doses. Dictotom blue (Mancozeb) + Nimbus (Micobuthanil) was used as commercial fungicide. After 21 days of application, disease severity was assessed according to scale 0-4. The results obtained according to the scale values were calculated to the % disease severity by applying the Towsend-Heuberger formula and the% effects of the biological preparations according to the Abbott formula. Test results were evaluated by Tukey multiple comparison test using variance analysis with SPSS 21 statistical program. As a result, the difference between all the applications was found significant (p<0.05). Based on the results of the experiment, the lowest disease severity was obtained from T-22 (foliar application) (12.2%) against Venturia inaequalis. Disease severity was determined in the application of Dicotom blue + Nimbus (13.2%) and Mycorriza (14.8%) respectively. The percentage of disease severity in control plants was observed as 40.2%. In the experiment, it was determined that the highest % efficacy values of the biological preparations were for T-22 (foliar application) (69.65%), T-22 (foliar application) + B. subtilis (foliar application), (67.66%) Dikotom blue+Nimbus (67.19%) and mycorrhiza (soil application) + B. subtilis (foliar application), (64.18%) respectively. The lowest % efficacy values of the biological preparations were determined in the application of B. subtilis (foliar application) (48.76%), T. harzianum (soil application) (53.23%) and T-22 (soil application) + B. subtilis (foliar application) (58.71%). As a result, biological preparations could be used as an alternative to chemical control, because of its positive aspects in terms of environment and food safety.