Relations Between Phenolic Compounds and Graft Success in Walnut (Juglans Regia L.)

State-of-the-art and Problems of Walnut Propagation Methods

“…They admitted that the high content of yuglon is the reason for poorer callus formation. In later studies, Karadeniz and Kazankaya (1997) confirmed those results and they established a reverse correlation between the callus formation process and the content of phenols in nine walnut cultivars. Lantos (1990) reported from 56% to 71% of survival rate after grafting of three cultivars; Stanisavljević and Mitrović (1997) -from 55% to 93% in a study with seven cultivars, while the results of Erdogan (2006) varied for the same cultivars, tested in two consecutive years.…”

Grafting-Take Success in Walnut (Juglans regia) under Different Environment Conditions

“…Grafting in walnuts is more difficult than in other fruit trees (Vahdati, 2005;Vahdati, 2006) and poor grafts take has always been considered a drawback in mass propagation of superior walnut selections . Temperature and humidity have major effects on the process of walnut graft uniting (Karadeniz, 2005;Sutyemez, 2007). Specially changing in temperature among the uniting period has direct effect on callus development and successful grafting (Rongting et al, 1993).…”

“…Also high environmental moisture is needed for winter grafting, because the parenchyma cells of callus have soft walls and they lose their moisture in dry places and poor grafts take has always been considered a drawback in mass propagation of superior walnut selections (Vahdati, 2003;Rongting et al, 1993). Accordingly, outdoor grafting is always restricted by the time of year when such favorable temperatures can be expected (Hartmann et al, 2001;Karadeniz, 2005).Various methods of vegetative propagation in walnut have been reported to give varying degree of success under different climatic conditions in India and abroad. The variations are dependent on different environmental conditions to which the plants are subjected before and after propagation (Ibrahim et al, 1978;Awasthi et al, 1982;Qureshi et al, 1985).…”

Preliminary Evaluation of the Impact of Antioxidants Polyvinylpyrrolidone and Ascorbic Acid on Patch Budding of Persian Walnut

“…The important reason for low budding success in walnuts is the high phenolic content in this plant. In the wound caused by budding, these compounds are oxidized by phenol oxidases and molecular oxygen and turned into complex of molecules that are brown or dark what results in necrosis of the tissues at the site of the budding (Karadeniz 2005). It should be noted that the percentage of budding success among different cultivars and genotypes is significantly different probably also because of differences in their phenolic materials content Vahdati & Zareie 2005;Karadeniz 2005).…”