Potasyum Sülfat Gübresinin Loring Şeftali Çeşidinin Dona Dayanımına Etkisi Üzerine Araştırmalar

This study was carried out in central of Tokat province, in 1998 and 1999, to determine the effect of potassium sulphate application at different rates on the frost resistance of Loring peach variety. Fertilisers were applied in 20 or 25 cm deeps of soil as active doses 0, 100, 200, 300, 400 and 500 g K2O per tree on March 1998. One year old shoot samples were taken in December 1998 and in January, February and March 1999. After that shoots were exposured in frost tests at -20 °C for 8, 16 and 24 hours periods. The highest active bud ratios (respectively 58.19 %, 57.88 % and 57.77 %) were found by applications of 500 g, 200 g, and 300 g K2O /tree. The lowest average active bud ratio (50.01 %) was obtained from control (0 dose). The frost hardiness of shoots taken on February, January, December and March was 60.51 %, 56.77 %, 51.80 % and 51.34 % respectively.