Konservasi In Vitro Tanaman Jeruk Besar (Citrus maxima (Burm.) Merr.) Kultivar Srinyonya Menggunakan Osmotikum dan Retardan

In Vitro Conservation of Pomelo (Citrus maxima (Burm.) Merr.) cv Srinyonya Using Osmoticum and Retardant. Iswari S. Dewi, Gani Jawak, Ika Roostika, M. Sabda, Bambang S. Purwoko, and Widiati H. Adil. Pomelo is an underutilized citrus fruit with a potential for commercialization. Only some cultivars have been conserved ex situ, such as in home yards or in botanical gardens. Such collections are vulnerable to biotic and abiotic hazards. The goal of the experiment was to study the effect of osmoticum (sorbitol) and retardant (ancymidol) on in vitro growth of pomelo. Four-leaf in vitro shoots of pomelo cultivar Srinyonya were used as plant materials. Murashige-Skoog (MS) medium was used as the basal medium for the culture. The trial was arranged in a completely randomized design with three replications. The treatments consisting of MS + sorbitol (0, 20, 40, and 60 g/l) and MS + ancymidol (0, 1, 3, and 5 mg/l). The results indicated that based on plant height, number of new leaves, and visual plant architecture, sorbitol treatments from 20-60 g/l retard the growth of the pomelo plant significantly. On the other hand, ancymidol did not inhibit the pomelo growth significantly, but it was a suitable osmoticum for improvement of in vitro plant vigor, increasing green color of leaf, and increasing root initiation. Leaf senescence of in vitro plants cultured on media containing sorbitol 40 and 60 g/l began 20 week after storage. The best medium for conservation of pomelo cv Srinyonya was MS + 20 g sorbitol/l.