Assessing the influence of Benzylaminopurine (Bap) on in vitro shoot proliferation of pomegranate (Punica Granatum L.)

Abstract

Pomegranate (Punica granatum L.) is an economically important crop, characterized for its nutritious and pharmaceutical applications. However, traditional propagation methods have limitations in producing large quantities of high quality plantlets. Hence, this research was aimed at developing an efficient tissue culture protocol for the successful establishment and determining the best hormone concentration of Benzyl Amino Purine (BAP) for shoot proliferation of the Sri Lankan pomegranate variety, Cv. Nimali. The explants (axillary nodal segments,1cm long) and shoot tips (1cm long)) were derived from mature healthy mother plants, surface sterilized and introduced into full-strength woody plant media. After two weeks, newly developed clean shoots were transferred into multiplication media in which five different concentration of BAP 0.0 mg/l (T1, control), 0.25mg/l (T2) 0.5mg/l (T3), 1.0mg/l (T4) and 1.5mg/l (T5) were introduced. The cultures were incubated at 26 ± 2ºc under16/8 h light/dark period in the incubation room. The results indicated that the highest shoot bud formation (6.0/plant), along with maximum shoot height of (22.4 mm), the average of leaves (11.4/plant), highest bud multiplication rate of (6.0%), were observed in shoot tip explants treated with 1.5 mg/L BAP (T5) after two-week period. In contrast, axillary nodal segments without BAP (T1) exhibited the lowest values, with shoot bud formation (1.4/plant), shoot height (1.0 mm), number of leaves (1.4/plant), and a bud multiplication rate of (1.4%). These findings demonstrate that the addition of 1.5 mg/L BAP to shoot tip explants significantly enhances shoot proliferation and growth in the Sri Lankan pomegranate variety, Cv. Nimali.