Browsing by Author "Chandrarathna, W.P.R."

Now showing 1 - 3 of 3
  • No Thumbnail Available
    Item
    Determination of a Suitable Hardening Medium for Micropropagated Anubias nana
    (Uva Wellassa University of Sri Lanka, 2016) Kumari, A.M.S.M.; Jayamanne, S.C.; Chandrarathna, W.P.R.
    Most of aquatic plant varieties are used in aquariums as ornamental plants due to their aesthetic and ecological value. The genus Anubias of the family Araceae is considered as one of the highly demanded plant types among other aquatic plant species. Among Anubias varieties, A. barteri var. nana is considered as a most cultivated and commercially important species. Micropropagation is currently applied to this plant as a tool for large scale multiplication of plants since the planting material has a very low multiplication rate. However, the high rate of mortality experienced by micro propagated plants during or following laboratory to outdoor transfer is still existing as a major limitation in large scale applications. Therefore, it is a requirement to develop an effective acclimatization procedure for a successful establishment and survival of plantlets. The present experiment was carried out in order to determine a suitable hardening medium for micropropagated Anubias nana using complete randomized design. The study was conducted at the Ornamental Fish Breeding and Training Centre, Rambadagalle. Four weeks old uniform sample of in vitro rooted Anubias nana plantlets were hardened by using five different potting media. Coir dust, coconut husks, clay brick shards, boggy soil and sand were used as different hardening media/treatments. Each treatment was replicated ten times. Every plantlet was provided with a constant amount (N: P: K-4:2: 1) of a commercial fertilizer in once a week. The performances of plantlets were measured by using survival rate and growth in each treatment. The measured growth parameters were number of roots and leaves, length of roots and leaves, fresh weight and dry weight of plantlets after 6 weeks of hardening period. Data were analyzed by using one way ANOVA and Tukey's test. The maximum survival percentage (100%) was obtained in coir dust, clay brick shards and sand. Out of five treatments of media, a significant difference (p<0.05) of root growth was shown by plantlets in coconut coir dust and sand. A significant difference (p<0.05) of leaf growth and weight was reported in plantlets in clay brick shards media. Keywords: Anubias nana, Micropropagation, Hardening
  • No Thumbnail Available
    Item
    Determination of Suitable Breeding Substrate for Redside Barb (Puntius bitnaculatus) in Captive Conditions
    (Uva Wellassa University of Sri Lanka, 2018) Wajiramala, G.K.Y.; Mahaliyana, A.S.; Chandrarathna, W.P.R.; Jayamanne, S.C.
    Redside barb (Puntius biniaculatus) is one of the most popular indigenous ornamental fish species, which commonly found in Sri Lanka. This species has been heavily collected from wild for aquarium trade and have a severe influence on the reduction of naturally available stocks. Development of captive breeding and larval rearing techniques are found as an effective strategy to increase commercially available stocks, which will also lead to ensure the sustainable utilization as a valuable resource. Hence, the objective of this study was to determine the suitable substrate for successful breeding of Redside barb in captivity. Three types of breeding conditions; gravels with aquatic plants, sand with aquatic plants, only aquatic plants were provided with stilled water in 60 cm x 30 cm x 30 cm size indoor glass tanks and three replicates for each treatment were used. Mature males with bright red colour stripe on their body and females which released yolked eggs, when slight pressure is applied on their abdominal region were selected as brooders for the experiment. Selected individuals were introduced into each tank at 2:1 male to female ratio. Completely Randomized Design was used as the experimental design and produced fry number was counted. Data were analyzed using one way ANOVA. Spawning was observed in all conditions and fry number varied significantly among three different substrates (p<0.05). The highest mean fry number was observed in the substrate of gravel with aquatic plants (195±20) compared to other 2 (fry number in the substrate which contain sand with aquatic plants: 77±39 and only aquatic plants: 33+33). Results of this study revealed that the most suitable breeding substrate for the Redside barb in indoor glass tanks was the substrate with a gravel bottom and aquatic plants.
  • No Thumbnail Available
    Item
    Study on Effects of Substrates for Captive Breeding of Dankolapethiya (Dawkinsia singhala)
    (Uva Wellassa University of Sri Lanka, 2018) Walisundara, W.M.N.K.; Mahaliyana, A.S.; Jayamanne, S.C.; Chandrarathna, W.P.R.
    Dankolapethiya (Dawkinsia singhala) is an endemic freshwater fish in Sri Lanka. This fish species has high ornamental value in export market and their natural stocks are diminishing day by day due to excessive collection by ornamental fish trade, and habitat degradation resulted by anthropogenic activities. Therefore, from the perspectives of the aquarium fish industry and conservation of the endemic fish species, captive breeding of this species is a good remedy. The objective of this study was to identify the ideal substrate under captive breeding environment. Four different substrate conditions created in cement tanks with size of 1.5 m x 0.75 m using coconut coir, sand, gravel and bare bottom and stocked fish at 2:1 male female ratio. Bottoms of the experimental tanks were fully covered with the selected substrates. Each treatment was triplicated. Height of the water column was maintained as 0.20 m. Breeding experiment was started, after 6 weeks of wild caught Dawkinsia singhala brooders' acclimatization period. Experimental tanks were observed closely for 7-14 days after commencement of the experiment and 63 individuals of fry were observed in the tanks with sand substrate condition. Out of four different substrates, captive breeding was only successful in experimental tanks with sandy bottom substrate, while spawning of Dawkinsia singhala was not successful (0%) in other experimental tanks. The study revealed that Dawkinsia singhala can be successfully bred under sand substrate condition in still water. This study will assist researchers to further develop captive breeding techniques for this species.