http://ir.lib.ruh.ac.lk/handle/iruor/20822 2026-10-07T23:48:01Z http://ir.lib.ruh.ac.lk/handle/iruor/21988 Effect of fertilizer schedules and media composition on growth and yield of capsicum chinense jacq. Under protected house conditions in a warm and humid climate Ekanayaka, R.I.; Adhikaram, K.K.L.B.; Fernando, K.M.C. Capsicum chinense Jacq. is an important vegetable crop cultivated widely in tropical and subtropical regions. The present study evaluated the effects of fertilizer schedules and growing-medium compositions on the growth and yield of C. chinense under protected conditions in the Low Country Wet Zone of Sri Lanka. Three fertilizer schedules (F1: existing fertilizer schedule), F2: fertilizer schedule 2, and F3: fertilizer schedule 3) and three growing-medium (M1: 50% coir dust + 30% partially burnt paddy husk + 20% coco chips (existing medium), M2: 70% coir dust + 30% partially burnt paddy husk, and M3: 70% coir dust + 30% coco chips) were evaluated in a two-factor factorial Completely Randomized Design with four replicates. The existing fertilizer schedule and growing medium served as the control treatment. The recorded parameters included the number of branches per plant and stem girth as growth parameters, and time to first flowering as a developmental (phenological) parameter. Pod circumference, number of pods per plant, fresh weight per pod, and pod weight per plant were recorded as yield-related parameters. Pod yield was graded according to market standards as a yield-quality parameter. In addition, the cost of production for each treatment was calculated. The interaction between fertilizer schedule and growing-medium composition did not significantly affect any measured parameters. However, fertilizer schedule significantly influenced the number of branches per plant, time to first flowering, pod circumference and pod weight per plant, pod grading, and benefit-to-cost ratio. Growing-medium composition significantly influenced stem girth. The results showed that 99% of the harvested pod yield met marketable standards for weight and colour. Based on the results, the existing fertilizer schedule can be recommended as the best fertilizer schedule among the tested schedules, and any of the three growing-medium compositions can be used to achieve satisfactory growth and yield of C. chinense under a warm, humid tropical environment. 2026-01-01T00:00:00Z http://ir.lib.ruh.ac.lk/handle/iruor/21987 Development and characterization of cassava starch-coated biodegradable packaging sheets from corn husk, corn silk, cassava peel, and banana peel waste Hettiarachchi, H. A. P. W.; Kaumadi, K. O.; Rathnayake, R. M. I. K.; Osemwota, I.O. The accumulation of petroleum-derived single-use plastic packaging has created a strong need for biodegradable materials from renewable, low-cost resources. This study developed biodegradable packaging sheets coated with cassava starch using corn husk, corn silk, cassava peel, and banana peel waste. The raw materials were washed, cut, alkaline-pulped with sodium carbonate, blended into a homogeneous pulp, and formulated into three treatments by varying corn husk content (T1: 100 g, T2: 200 g, and T3: 300 g), while cassava peel, banana peel, and corn silk were kept constant. Bentonite, rosin-alum, and over-matured okra mucilage were incorporated to improve sheet formation and bonding. The molded sheets were sun-dried and coated on both surfaces with a cassava starch-polyvinyl alcohol bioplastic coating plasticised with glycerol. The developed sheets were evaluated for moisture content, water absorption, thickness, grammage, tensile strength, solubility, and soil-burial biodegradability. Significant treatment effects (p < 0.05) were observed for the major physical and mechanical properties. T3 showed the highest thickness (1.926 ± 0.029 mm), grammage (617.7 ± 16.41 g/m²), moisture content (7.163 ± 0.150%), water absorption (385.5 ± 11.42%), and tensile strength (2.1067 ± 0.03 MPa). However, biodegradation was fastest in T1, which reached 63.33 ± 2.00% weight loss after 49 days, compared with 52.00 ± 2.00% for T2 and 37.33 ± 2.00% for T3. All treatments showed low solubility (<4%) in distilled water, acetic acid, sodium hydroxide, and ethanol after 24 h immersion. The results indicate that agricultural wastes can be converted into biodegradable single-use packaging sheets, with T3 offering better structural performance and T1 showing faster environmental degradation. Further hydrophobic coating optimization is recommended for wet food-contact applications. 2026-01-01T00:00:00Z http://ir.lib.ruh.ac.lk/handle/iruor/21679 Formulation and quality determination of herbal carbonated soda enriched with coriander, tamarind and green apple as natural base ingredients Bandara, R.G.N.B.; Somaratne, G.M.; Prasantha, B.D.R. Herbal-inspired beverages represent a promising avenue for developing functional, naturally flavored carbonated drinks. This study aimed to formulate and characterize three soda formulations based on coriander (Coriandrum sativum), tamarind (Tamarindus indica), and green apple (Malus domestica), enriched with commercially available ingredients such as dried barley seeds (Hordeum vulgare L.), dried ginger (Zingiber officinale), fresh beetroot (Beta vulgaris) (for coriander formulation), dried ashwagandha (Withania somnifera) roots (tamarind formulation) and dried tulsi (Ocimum tenuiflorum) leaves (for green apple formulation). Each formulation was evaluated under three sweetening systems: bee honey, stevia, and a sugar–stevia blend to identify the most acceptable sensory profile (9-point hedonic scale, n=35). Sensory analysis indicated that the sugar–stevia blend consistently achieved the highest overall acceptability across all formulations, with mean ranks of 2.23 (coriander), 2.93 (tamarind), and 2.43 (green apple). Physicochemical evaluation revealed that the formulated sodas exhibited higher pH values (4.76, 2.70, 3.01) compared with a commercial cola (2.63), lower total soluble solids (4.29 – 6.04 oBrix vs 10.08 °Brix), reduced total and reducing sugars (2.27 – 9.02 g/100 mL vs 10.51 g/100 mL), and markedly lower sodium content (1.50 – 8.31 mg/L vs 51.23 mg/L). Carbonation levels were lower (1.08 1.14 volumes CO₂) relative to cola (3.74 volumes CO₂). Functional analysis demonstrated enhanced bioactive properties, with ascorbic acid concentrations ranging from 6.28 to 20.99 mg/100 mL, total phenolic content of 192– 374 mg GAE/L, and DPPH radical-scavenging activity up to 58.58% in coriander soda. Total plate count analysis confirmed microbiological stability during 14 days of refrigerated storage, with no significant increase (p > 0.05) in microbial counts, which ranged from 730 – 1000 CFU/mL at baseline to 590 – 600 CFU/mL after storage. The pH of all soda formulations increased during storage (from 2.70 – 4.76 to 2.86 – 4.89), with greater increases observed at elevated storage temperatures (25 and 40°C) than under refrigerated conditions (4°C). These findings indicate that herbal carbonated sodas can deliver a nutritionally enriched, low-sugar (total and reducing sugar), and sensory-acceptable alternative to conventional soft drinks. 2026-01-01T00:00:00Z http://ir.lib.ruh.ac.lk/handle/iruor/21674 Analysis of extreme rainfall and flood events: a case study of the Nilwala river basin Rajawatta, K.M.W.; Ranahansi, H.K.N.; Jayaweera, W.M.C.S. The analysis of extreme hydrological events in river basins and rainfall trends is crucial for reducing vulnerability to flooding and developing flood mitigation strategies. Understanding the correlation between flooding and rainfall patterns helps identify flood-prone areas within the region, plan infrastructure, and improve early warning systems, ultimately mitigating the negative impacts of future flood events and protecting communities and resources. The objective of this study was to determine the relationship between rainfall and anomalous flood occurrence in the Nilwala River Basin (NRB) using statistical analyses. The study was conducted in the southern province of Sri Lanka.While NRB is characterised by monsoon-induced flooding, an unusual flood event was reported recently. Thalgahagoda, Panadugama, Pitabeddara and Urawa represent the four main gaging stations (GS) of NRB. Water level (m) and rainfall (mm) data were collected from each GS for September, October, November, and December over four consecutive years (2021, 2022, 2023, and 2024). The study investigated differences in water levels and rainfall among stations, and the correlation between rainfall and flooding patterns, by analysing the collected data using One-way analysis of variance (ANOVA) and Duncan's multiple range test (DMRT). All stations recorded a significant increment of their highest peak water levels in 2023, compared to previous years: Thalgahagoda (1.69 ± 0.47), Panadugama (5.35 ± 0.99), Pitabeddara (1.84 ± 0.68), and Urawa (1.17 ± 0.51) indicating a potential rise in flood intensity while rapid recovery of water levels was reported in every GSs (1.15 ± 0.39), (4.40 ± 1.07), (1.22 ± 0.55) and (0.63 ± 0.34) respectively in 2024. Results revealed no statistically significant differences in rainfall amounts across the years considered, with only slight variation in mean rainfall values. However, Pitabeddara consistently recorded the highest rainfall in all three years, peaking at 26.46 ± 33.15 mm in 2023. The findings indicate that although interannual rainfall was not significant over the period considered, the downstream section of the basin has been affected by the observed anomalous flood levels. However, the results show a weaker correlation between rising water levels during flood events and consistent rainfall patterns, indicating the potential influence of anthropogenic activities. Overall, the study emphasizes the urgency of enhancing flood management strategies and investigating potential anthropogenic factors, particularly in flood-prone areas such as Thalgahagoda and Panadugama. 2026-01-01T00:00:00Z