The effects of some fertilizer and doses used in strawberry production on Macrophomina phaseolina colony development and microsclerotia formation

The aim of this study is to evaluate the effects of some nitrogenous, phosphorus and potassium fertilizers and their doses on charcoal rot disease caused by Macrophomina phaseolina in strawberry plants. Highly virulent M. phaseolina isolates (AMp2, AMp9, OMp1) isolated from strawberry fields were used in this study. Some of the recommended doses for nitrogenous, phosphorus and potassium fertilizers ammonium sulfate, ammonium nitrate, urea for 10,5 kg/da-21 kg/da-42 kg/da-63 kg/da-84 kg/da, phosphoric acid for 5,5 kg/da-11 kg/da-22 kg/da-33 kg/da-44 kg/da, potassium sulfate for 16 kg/da-32 kg/da-64 kg/da-96 kg/da-128 kg/da for strawberries were added for each character separately to the PDA medium and M. phaseolina colony growth, microsclerotia count and size were determined. The trials were conducted with 5 replications for each isolate and fertilizer doses. There was no positive or negative effect between isolates and fertilizer for M. phaseolina colony development. The lowest amounts of microsclerotia were found in OMp1 isolate at doses of K1 and K2 in potassium application. The effects of potassium sulphate and phosphoric acid fertilizers on amount of microsclerotia of were lower in all 3 isolates than nitrogenous fertilizers. Microsclerotia size of Omp1 isolate was found to be larger in both potassium sulphate and phosphoric acid fertilizers than other isolates and nitrogen fertilizers. Key Words: Ammonium sulfate, Ammonium nitrate, Urea, Potassium sulfate, Phosphoric Acid, charcoal rot, Strawberry