Factors affecting the success potential of grafting related to persimmon cultivation in Nepal.

摘要

Local persimmon (Diospyros kaki) cultivars Kirtipur, Khopasi, Nuwakot, Khawa, Dhaula, Baluwatar, Teku, Dhading and some Japanese persimmon species were grown in Kathmandu, Nepal for rootstock selection and quality measurement. In addition, 2-year-old D. kaki and D. lotus trees grown in plastic containers at an orchard in Tsukuba, Japan were used in this experiment. Scions of Nepalese astringent and Japanese non-astringent types were budded and grafted onto local and selected cultivars to evaluate the effects of cultivar and grafting method on graft union development. The methods used in this experiment were T-budding, veneer and tongue grafting. Visual evaluation was done at 1, 3, 5, 7, 9 and 12 months, and 1.5 and 2.5 years after grafting. Top-worked plants had higher percentage success than others. In situ grafting yielded better results than grafting done on transplanted rootstocks. Initial response to grafting included the development of callus cells along the cut surfaces of the rootstock and scion. Necrosis of xylem elements near the cut surfaces was observed, and after 3-12 months, new generating and connective tissues were seen in the transverse sections across necrotic callus cells at the base of the scion. After 1 to 3 years of grafting, the graft union zone of D. lotus showed more necrotic points than D. kaki which resulted in tree weakening in Fuyu/D. lotus combination..