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Kiwifruit micropropagation was first described by Harada (1975) and has been reviewed by several authors (Revilla et al., 1992; Ferguson et al., 1996; Kumar and Sharma, 2002; Rugini and Gutiérrez-Pesce, 2003; Oliveira and Fraser, 2005; Wang and Gleave, 2012). Nodal segments or shoot apices are disinfested with sodium hypochlorite (up to 1.5%, w/v) with a few drops of detergent and then cultured on MS-based medium (Murashige and Skoog, 1962) with several phytohormone combinations (for details see Revilla et al., 1992). Other culture media used are B5 medium (Gamborg et al., 1968; Barbieri and Morini, 1987) or Quoirin medium (Quoirin and Lepoivre, 1977) as modified by Standardi (1981). Zeatin is widely used for shoot proliferation because benzyladenine (BA) causes hyperhydricity of leaves (Marino and Bertazza, 1990); however, another study of the effect of BA on kiwifruit apical shoot cultures did not show hyperhydricity (Moncaleán et al., 2001). Thidiazuron and m-topolin have also successfully been used for micropropagating two male cultivars (Prado et al., 2005). The best proliferation rates are five shoots per explant in several reports (Standardi, 1983; Standardi and Catalano, 1985). Inhibition of ethylene in apical segments using aminoethoxyvinylglycine (AVG), 1-methylcyclopropene (1-MCP) or its reduction in the culture atmosphere with ventilated flasks increases the number and length of shoots produced per explant (Arigita et al., 2003, 2004).

Rooting of microshoots has been achieved by a short (15–20 s) pulse with a high indole-3-butyric acid (IBA) concentration (up to 5 mM), followed by transfer to half-strength Cheng (1975) culture medium (González et al., 1995c) or to a sterile substrate mixture for ex vitro rooting (Monette, 1986, 1987). Kiwifruit microshoots have also been rooted with lower concentrations of IBA for a longer period and transfer to medium with activated charcoal (Harada, 1975; Revilla and Power, 1988). Acclimatization can be achieved by gradually reducing relative humidity (Marino and Bertazza, 1990; González et al., 1995c). Reduced light during acclimatization can improve survival (Shen et al., 1990; Pedroso et al., 1992). Carbon dioxide enrichment (up to 600 μmol/mol) of the culture atmosphere of kiwifruit explants also improves acclimatization (Arigita et al., 2002).

Conventional propagation of kiwifruit is being supplemented by micropropagation due to increasing demand for plant material (Oliveira and Fraser, 2005). Micropropagated plants show a 1-year delay in flowering and lower efficiency in energy uptake and partitioning of photoassimilates (Oliveira and Fraser, 2005) that has been ascribed to tissue culture-induced juvenility (Díaz Hernandez et al., 1997).