Weerasekara, W.N.V.Bambaranda, B.V.A.S.M.Jayamanne, S.C.Krishnarajah, S.A.2021-12-142021-12-1420169789550481095http://www.erepo.lib.uwu.ac.lk/bitstream/handle/123456789/7986/6-2016-Development%20of.pdf?sequence=1&isAllowed=yThis research was focused on the development of successful propagation protocols for two different endangered and threaten aquatic plant species of A. rigidifolius and A. jacobsenii. Due to lack of effective propagation methods, Aponogeton species indiscriminately harvested from wild and leads to extinct. To overcome the problem of species loss and inadequate supply to the local and foreign market, in vitro and conventional propagation protocols were developed for both species. Rhizomes, seeds and leaf explants of both species were sterilized using NaOCI and 0.1 % HgC12 and established on full strength MS medium supplemented with combination of 6- benzylaminopurine (BAP) 2, 3, 5 mg/L with or without 0.1 mg/L indole acetic acid (IAA) for initiation. For shoot multiplication 2, 3, 5 mg/L BAP were used. Rhizome cuttings and seeds of both species were planted in pots, which contain sand, sand: top soil, top soil and boggy soil with water as conventional propagation method. Experiment was arranged in Complete Randomized Design method and data were analyzed using ANOVA and Tukey's Test. The presence of growth regulators had significant effect (p<0.05) on shoot initiation of A. rigidifolus rhizome. The highest shoots per replicate (2.4) were proliferated in 2 mg/L BAP medium. Application of hormones had a significant effect on number of leaves and seedling height of seed explants of both species. Maximum number of leaves (5) and seedling height (5.8cm) in A.rigidifolius obtained from the treatment which supplemented both 5 mg 1-' BAP and 0.1 mg IAA while the highest leaves (3.43) and height (1.92 cm) shown in 5 BAP alone medium in A. jacobsenii seedlings. The highest shoots per seedling (4.2) obtained from 2 mg BAP contain multiplication medium in A. rigidifolius seedling. Conventional growth media significantly influence on the shoot development from A. rigic4folius rhizome cuttings, seed germination, and in other seedling growth parameters of both species. Mean number of leaves, height of seedlings, and number of roots and length of roots were high in both plants which planted in boggy soil medium. The highest shoots ofA. rigidifolius obtained in sand medium. Keywords: Aponogeton rigidifolius, Aponogeton jacobsenii, in-vitroenAquatic ResourcesPlantBotanicOther