Developing Micropropagation Protocols of Date Palm (Phoenix dactylifera L.) cv. Barhi Using Shoot Tip Explants

Present study described stepwise micropropagation protocols and field performance for elite exotic date palm cv. Barhi using juvenile shoot tip explants. Initially, the shoot tip was surface disinfected using 2 g L−1 mercuric chloride (HgCl2) and finally with 40% sodium hypochlorite (NaOCl) solution resulted in a highest explant survival. Results showed that significantly highest callus was induced in 86% of the shoot tip explants within two months under full dark on the medium containing 100 mg L−1 2,4-dichlorophenoxy acetic acid (2,4-D) and 3.0 mg L−1 2-isopentenyl adenine (2iP). The differentiation medium containing 50 mg L−1 2,4-D and 3.0 mg L−1 2iP induced 83% somatic embryos from callus under full dark conditions. Under light, the medium containing naphthalene acetic acid (NAA) 0.1 mg L−1 and kinetin (Kin) 0.1 mg L−1 resulted in the highest multiplication and germination (88%) of somatic embryos. Significantly highest leaf number, leaf length, root number and root length were obtained on MS medium containing 0.1 mg L−1 NAA. Root trimming at proper rooting stage helped in production of multiple roots in each plantlet. Plantlets ready to shift in the greenhouse were exposed to in vitro hardening for bringing physiological and anatomical changes. Healthy plantlets (avg. 15 cm) with 2–4 leaves and multiple roots were selected for acclimatization. Maximum survival rate (95%) of plantlets in the greenhouse after 1 month (1 M) was obtained on the soil medium containing peat moss, river sand, yellow sand (3:1:1). During field performance of micropropagated date palm trees of cv. Barhi produced normal fruits similar to the fruits of mother tree in size, shape, colour and taste. The obtained results will be useful to micropropagate other local and exotic cultivars of date palm in the area and worldwide. © 2023, The Author(s), under exclusive licence to The National Academy of Sciences, India.