P. BOTYANSKI, V. ROYCHEV and D. BRAYKOV
Agricultural University, BG-4000 Plovdiv, Bulgaria
BOTYANSKI, P., V. ROYCHEV and D. BRAYKOV, 2001. Influence of direct current upon bud dormancy in grape vine (Vitis vinifera L.). Bulg. J. Agric. Sci., 7: 373-379
Investigated was the influence of direct current upon bud dormancy in grape vine. It was established that a 24-hour treatment with direct current with voltage of 60 V, anode (+) attached to the acropetal end of the vine cuttings and cathode (–) attached to the basipetal end of the vine cuttings causes break of bud dormancy in grape vine. This effect is most strongly expressed in Bolgar, followed by Cabernet Sauvignon and Mavrud, when applied on early dates (1 October and 1 November) at the time when the winter buds are in deep dormancy. The polarity of the vine plant determines an earlier initiation of the outermost buds – those from the 15th sector, and latest growth of the buds from the lower sector – the 5th sector of the shoots. Treatment with direct current on later dates (1 December) nullifies the effect of its application and causes a reverse (inhibiting) effect retaining the development of the lower situated buds from the 5th and 10th nod.