استفاده از روش قلمه گيري براي برداشتن بيماريهاي باكتريايي ساق سياه و پژمردگي باكتريايي در سيب زميني

USING STEM CUTTING METHOD TO CONTROL BLACK LEG AND BACTERIAL WILT DISEASES IN POTATO

During two successive years, 2000 to 2001. the effect of propagating by stem cutting for eradication of bacterial agents of potato black leg and bacterial wilt diseases were evaluated. Rooting percentage and amount of minitubers production and the efficiency of this method to control bacterial disease were determind. Potato seeds from four cultivars; `Agriaʹ, `Dragaʹ, `Marfonaʹ and `Concordʹ were selected. In the first step, the health of tubers was certified by bacterial test. These tubers were inoculated with two bacterial suspension and then cultivated in factorial design containing 12 treatments, namely, four cultivars and bacterial agent in three levels (two bacterial inoculums and control). Terminal cuttings were prepared as plants attained 15 to 20 cm in length. Cuttings were cultured in perlite medium and rooting percentage was accounted. Production of minitubers from each cutting was determind. Samples of explants from stem cuttings and minitubers were taken in successive periods of growing period. The amount of contamination was determined by biochemical and physiological standard tests. Results showed that rooting percentage in different treatments did not significantly different at 5% level. Regarding minituber production, only cultivars had significant effects and `Agriaʹ produced highest minitubers. The data of bacterial tests did not show any bacterial agent in minitubers which means terminal stem cultings in potatoes elimianate these two bacterial diseases.