effects of iba and ga3 on increasing the efficiency of patch budding in some persian walnut cultivars

abstract persian walnut is one of the most important nut crops in iran. now the majority of orchards are seedling with a great diversity. for establishing uniform orchards and increasing the quantity and quality of yield, patch budding as the most suitable propagation methods, have still technical and practical problems in the country. in spite of high percent of primary success in patch budding but the final success is very low. in this study, the effects of indole-3- butryic acid (iba) and gibberellic acid (ga3) were evaluated on four cultivars and one genotype of walnut to increase bud growth and graft success. the results showed that there were significant differences among the different levels of both the hormone on increasing total success of budding, bud growth and decreasing dried and dormant buds. mean comparisons showed that iba 50 ppm with %56 in comparison with control with %26 had the highest effect on bud growth. meanwhile the other hormone treatments increased the bud growth at least %20 comparing with control. among the cultivars, the highest and lowest bud growth belonged to ‘chandler’ (%58) and ‘z63’ (26). the interaction between hormone treatments and cultivars on bud growth showed that ‘chandler’ had the highest response to ga3 100ppm and iba 50 ppm, ‘pedro’ to iba50, while for ‘z63’ iba 100 had the best effect. this study showed that suitable hormone treatment could overcome a part of problems relating to low level of graft success in walnut.