A hydroponic-based efficient hardening protocol for in vitro raised commercial kiwifruit ( Actinidia deliciosa )

Actinidia deliciosa is a commercially important plant receiving recognition because of its high nutritive value. This study presents an efficient protocol for the hardening of in vitro raised Actinidia deliciosa plants using a hydroponic method. Leaf explants inoculated on Murashige and Skoog (MS) medium supplemented with 5.00 μM 6-benzylaminopurine (BAP) and 1.00 μM α-naphthaleneacetic acid (NAA) resulted in 5.28 ± 0.14 shoots per explants and 8.33 ± 1.80 cm average shoot length. Rooting was achieved through half-strength MS medium supplemented with 1.5 μM indolebutyric acid (IBA) and 0.6 μM BAP. Maximum root number (12.76 ± 1.08) and 6.78 ± 0.25 cm average root length were recorded from plantlets using half-strength MS medium supplemented with 1.5 μM indolebutyric acid (IBA) and 0.6 μM BAP. In hydroponic system, an average root length of 22.40 ± 0.59 cm, average root number of 21.50 ± 1.24, average leaf number of 4.50 ± 0.40, and average shoot length of 9.71 ± 0.29 cm were observed in Hoagland & Arnon solution. The early development of shoots, roots, and leaves through hydroponics was advantageous in establishment of micropropagated plants in a greenhouse. Complete 100% plant survival was found by following proper acclimatization using hydroponic method. The study underlines the efficient hardening of micropropagated plants of A. deliciosa through hydroponic technique in Himalayan region.