The production of japanese persimmon (Diospyros kaki) plants by grafting on seedling rootstocks results on vegetative variability problems. The goal of this work was to develop a protocol for bud regeneration using buds obtained by indirect root organogenesis. Explants were obtained by root segments of embryos germinated from mature seeds. The breeds were isolated in vitro on MS½NO3 medium. Seeds were sterilized by immersion in 70% ethanol for 1 min following immersion in 2.5% sodium hypochlorite for 20 min. They were then washed four times with autoclaved water. In the first experimento, root segments of 2cm were isolated in MS½NO3 culture medium supplemented with 0.01µM indoleacetic acid and four cytokinins (zeatin, 6-benzylaminopurine, 2-isopentenyladenine and thidiazuron) at concentrations of 1 and 10µM each. The second experiment evaluated four periods in media contaning 10µM indolebutyric acid (0, 5, 10 and 15 days) for shoot rooting. The highest bud regeneration (1.2 buds/explant) was observed when a combination of 1µM zeatin and 0.01µM indoleacetic acid was used. The juvenile buds obtained showed natural potential for rooting, but additional experiments are needed to confirm the auxin effects.
Diospyros kaki; tissue culture; growth regulators; micropropagation
