EFFECT OF CALLUSING CONDITIONS ON GRAFTING SUCCESS IN WALNUT (Juglans regia L.)

This experimental study was conducted at the Fruit Research Institute, Cacak, Serbia, to determine bud break and callus formation dates, the degree of callus formation, grafting success on day 20 after grafting and overall grafting success on day 28 after grafting in walnut (Juglans regia L.) under different treatments and bench grafting conditions in cultivar Seinovo (control) and the selections ‘Ovcar’, ‘G-286’, ‘Elit’ and ‘G-139’. Three treatments were applied: Treatment 1 – covering the graft with sawdust up to the top of the scion without dipping the scion and graft union in paraffin; Treatment 2 – covering the graft with sawdust up to the top of the scion and dipping the scion and graft union in paraffin; and Treatment 3 – covering the graft with both sawdust, up to the top of the scion, and polyethylene foil, and dipping the scion and graft union in paraffin. The best results of the parameters tested were obtained in the treatment involving dipping the graft in paraffin and covering it with both sawdust, up to the scion, and polyethylene foil. The treatment without the use of paraffin, involving only the covering with conifer sawdust up to the top of the scion yielded the