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1976_ Vidurava 01 (02) English
(Colombo : National Science Council of Sri Lanka ; Vidurava Issue, 1976) Jayaratne, O.; Subasinghe, T.B.; Djojohadikasumo, S.; Laurentius, S.F.; Gunathilake, S.; Dharmawardane, C.; Chidambarapillai, P.M.; Colombo Campus; Rubber Research Institute; National Science Council
Genetic control of fruit length, external colour and number of fruits per vine in bitter gourd studied using Charantia × Muricata crosses
(National Science Foundation: Colombo, 2024-01-02) Kumari, H.M.P.S.; Nisansala, P.U.; Wijewardhana, E.P.; Sumanasinghe, D.P.; Abeysiriwardena, D.S. De Z.; Kusalani, T.L.C.N.
The present study was undertaken to ascertain the genetic control of external fruit colour, fruit length, and the number of fruits per vine in bitter gourd using reciprocal crosses of Momordica charantia var. muricata and M. charantia var. charantia and to identify suitable lines of M. charantia var. muricata to be used in bitter gourd improvement programmes. Muricata accession collected from Girandurukotte (GK), Sri Lanka, was selected as a suitable accession for crop improvement based on higher gynoecy and consistency of characteristics. Crossing success between Charantia and Muricata varieties was 100 % indicating cross-compatibility between the two types. External fruit colour, fruit length and the number of fruits per vine of bitter gourd were found to be quantitative traits, potentially controlled by many genes, each with a small effect. The number of fruits per vine was found to show cytoplasmic inheritance, as the F1 generation recorded fruit numbers per vine similar to those of Charantia varieties, when Charantia varieties were used as the female parent of the reciprocal crosses made between Charantia and Muricata varieties. However, the suspected cytoplasmic effect was not useful, as it influenced to reduce the number of fruits per vine. In addition, the number of fruits per vine showed several transgressive segregants in both extremes of the F2 populations. In bitter gourd improvement programmes, GK Muricata accession may be used to improve cultivated Charantia varieties with respect to fruit characteristics such as external fruit colour, fruit length and the number of fruits per vine through a breeding program with the directional selection made towards obtaining the desired characters.
Risk assessment of heavy metals in the freshwater lake sediments around Eppawala phosphate deposit, Sri Lanka
(National Science Foundation: Colombo, 2024-01-02) Batapola, N. M.; Dushyantha, N. P.; Ratnayake, N. P.; Premasiri, H. M. R.; Panagoda, H.; Jayawardena, C. L.; Chandrajith, R.; Ilankoon, I. M. S. K.; Rohitha, L. P. S.; Ratnayake, A. S.; Koongolla, J. B.; Abeysinghe, A. M. B. K.; Dissanayake, D. M. D. O. K.; Ratnayake, R. M. P.
The Eppawala area in Sri Lanka has an agricultural-based economy. As a result, the recent agricultural intensification could increase the risk of heavy metal contamination in lakes in the area as the main water canal in the area, i.e., Jaya Ganga, flows across these lakes. Therefore, this study focuses on the risk assessment of heavy metals in the freshwater lake sediments in the Eppawala area and the identification of potential sources for heavy metal contamination in the lakes. Nine heavy metals (Cr, Mn, Co, Ni, Cu, Zn, As, Cd, and Pb) were investigated in surface sediments (n = 22) of the upstream and downstream lakes of the Eppawala Phosphate Deposit (EPD). The average heavy metal concentrations in the upstream lake sediments were higher than those downstream. Eppawala lake sediments were heavily polluted by As along with moderate to high Cr pollution. However, only As and Cd indicated considerable to moderate ecological risk levels to the local environment. The downstream lake sediments showed lower heavy metal contents compared to those upstream and had negative correlations between heavy metals and P2O5 contents. This reveals that the EPD does not contribute to the heavy metal contamination in the Eppawala lake sediments. However, the statistical analysis showed that heavy metals were mostly derived from similar pollution sources. Agrochemicals used in paddy cultivation in the vicinity might be a potential source of heavy metals. This study highlights the importance of implementing remediation to control the heavy metal pollution prevailing in the Eppawala lakes.
1976_ Vidurava 01 (01) English
(Colombo : National Science Council of Sri Lanka ; Vidurava Issue , 1976) Wijesekera, R.O.B.; Nayudamma, V.; Senanayake, U.M.; Vidanayagam, S.S.; Amarasiri, W.A.; Coconut Research Institute; Tea Research Institute; National Science Council of Sri Lanka
Evaluation of Taekwondo Poomsae movements using skeleton points
(National Science Foundation: Colombo, 2024-04-09) Fernando, W.M.U.; Sandaruwan, K.D.; Athapaththu, A.M.K.B.
Taekwondo is a widely practised martial art and an Olympic sport. In Taekwondo, Poomsae movements are essential, as they form the foundation of the sport and are fundamental for success in competitions. The evaluation of Poomsae movements in Taekwondo has been a subjective process, relying heavily on human judgments. This study addresses the above issue by developing a systematic approach to evaluate Poomsae movements using computer vision. A long short-term memory-based (LSTM-based) machine learning (ML) model was developed and evaluated for its effectiveness in Poomsae movement evaluation. The study also aimed to develop this model as an assistant for self-evaluation, that enables Taekwondo players to enhance their skills at their own pace. For this study, a dataset was created specially by recording Poomsae movements of Taekwondo players from the University of Colombo. The technical infrastructure used to capture skeleton point data was cost-effective and easily replicable in other settings. Small video clips containing Taekwondo movements were recorded using a mobile phone camera and the skeleton point data was extracted using the MediaPipe Python library. The model was able to achieve 61% of accuracy when compared with the domain experts’ results. Overall, the study successfully achieved its objectives of defining a self-paced approach to evaluate Poomsae while overcoming human subjectivity otherwise unavoidable in manual evaluation processes. The feedback of domain experts was also considered to finetune the model for better performance.