Scholarly Publications

Effect of iron (fe2+) toxicity on yield and yield components of selected high-yielding rice varieties under low country wet zone field conditions

2026-04-27T08:12:43Z

Effect of iron (fe2+) toxicity on yield and yield components of selected high-yielding rice varieties under low country wet zone field conditions De Silva, S.R.; Masakorala, K.; Withanawasam, D.M. Country Wet Zone. This study aimed to assess the effects of Fe2+ toxicity on grain yield and yield components of selected high-yielding rice varieties and analyse their sensitivity to iron toxicity by comparing yield and yield related parameters obtained under iron stress treatment with those recorded under control conditions. A field screening experiment was conducted during the 2023–2024 Maha season at the Regional Rice Research and Development Centre, Bombuwala, Sri Lanka using 15 rice varieties (BW272-6B, Bg359, BW372, BW302, At311, BW266-7, BW312, BW361, Bg300, BW367, BW364, BW267-3, BW363, Bg374, BW51). A site with high Fe2+ levels (294.45 to 317.10 mg kg−1) was selected to induce toxic effects, while a control site had low levels (78.90 to 112.63 mg kg−1). To evaluate the effect of iron toxicity on grain yield and yield components of 15 rice cultivars, a randomized complete block design (RCBD) with 3 replicates (n=3) was used. Grain yield per plant, along with plant height, tiller number, 1000 grain weight, and fertility (filled and unfilled grains per panicle), were recorded as yield components. A Generalized Linear Model was employed to assess the effects of treatment, variety and their interaction on yield and yield parameters. The results showed that BW267-3, BW367, BW363, BW372, BW302, and At311 had no significant differences in yield and yield components compared to the control, indicating high tolerance to Fe2+ toxicity. Conversely, BW272-6B and Bg359 showed significant reductions in yield (33%), 1000-grain weight (40%), fertility (25%), plant height (18%), and tillering (33%), thereby classifying them as susceptible. Other varieties were moderately affected and classified as moderately tolerant.

Effect of varieties and fertilizer practices on yield and quality of capsicum chinense jacq under protected culture

2026-04-21T08:42:30Z

Effect of varieties and fertilizer practices on yield and quality of capsicum chinense jacq under protected culture Dilshan, J.M.D.M.; De Silva, C.S.; Kodikara, K.M.S. Capsicum chinense Jacq, belongs to the family Solanaceae and is native to Central and South America. It has been widely cultivated in Sri Lanka as a commercial crop. This study was undertaken to identify the most suitable combination of fertilizer and C. chinense variety to enhance growth, yield, and fruit quality, aiming to optimize C. chinense production, reduce input wastage, and increase profitability for farmers. This experiment was conducted at the Regional Agriculture Research and Development Center, Bandarawela using a Completely Randomized Block Design with a two-factor factorial arrangement, four replications, each with six plants. Two factors were fertilizers: Albert’s solution and Kodimix® and five C. chinense varieties: Piquante, Hot dragon, Dark green, Light green, and M1HP1. Ten treatment combinations were tested, pairing each variety with one of the two fertilizers for growth yield and quality parameters. The results indicated that the treatment effect was statistically significant (P<0.05) for most measured parameters. The results of the present investigation indicated that, among the treatments, Piquante × Kodimix® yielded the highest per-plant yield (0.92 kg) and was therefore considered the best treatment.

Validation of scar markers for early sex determination in papaya (carica papaya l.) under Sri Lankan conditions

2026-04-21T07:56:15Z

Validation of scar markers for early sex determination in papaya (carica papaya l.) under Sri Lankan conditions Priyadarshani, A.G.W.; Mewan, K.M.; Wikramasinghe, W.T.S.S.; Perera, UI.P.; Pinthujan, P. Papaya (Carica papaya L.) is a commercially important tropical fruit crop exhibiting three sex types: male, female and hermaphrodite. Because sex expression cannot be identified morphologically at the seedling stage, excess plants are often maintained until flowering, resulting in inefficient use of land, labour and inputs. This study evaluated the transferability and diagnostic performance of widely used sequence-characterized amplified region (SCAR) markers for early sex identification in a Sri Lankan papaya population. Fifty randomly selected 40–45 day-old seedlings from a controlled hermaphrodite × hermaphrodite (H×H) population were screened using SCAR-W11 and SCAR-T12 markers, with SCAR-T1 used as a positive amplification control. SCAR-W11 and SCAR-T12 amplified a specific ~800 bp fragment in hermaphrodite plants, whereas no amplification was observed in female plants. Morphological assessment at flowering showed complete agreement between molecular marker-based identification and phenotypic sex classification within the evaluated dataset showing complete agreement between molecular and morphological sex identification. These findings indicate that SCAR-W11 and SCAR-T12 are reliable markers for distinguishing hermaphrodite and female papaya seedlings under Sri Lankan conditions and can facilitate more efficient nursery management and breeding programs.

Evaluation of the nutritional, functional, and glycemic properties of commercially available white, finger millet, and multigrain breads in sri lanka

2026-04-21T05:19:06Z

Evaluation of the nutritional, functional, and glycemic properties of commercially available white, finger millet, and multigrain breads in sri lanka Tennakoon, T.M.P.M.; Somaratne, G.M.; Jayawardhane, M.R.M.P.; Dilrukshi, S.A.D.A.; Prasantha, B.D.R. With the ongoing increase in metabolic syndrome cases worldwide and the importance of carbohydrate quality for glycemic control, assessing the nutritional and functional qualities of commonly consumed staple foods is of great importance. This study assessed the nutritional composition, glycemic index (GI), functional properties and overall loaf suitability of three commercially available bread types: white, finger millet and multigrain bread for managing metabolic syndrome. While the nutritional parameters were measured using standard AOAC methods, the Folin–Ciocalteu reagent method and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay were used to analyse the total phenolic content (TPC) and antioxidant activity of breads, respectively. Eighteen non diabetic, healthy participants with an average BMI of 21.2±1.7 kg/m2 underwent GI studies in accordance with ISO 26642:2010 protocols. The studies were conducted after a 10-12-hour fast, measuring the blood sugar response over 2 hours from the time of consumption of bread samples containing 50 g of available carbohydrates. The results indicated that the three breads differed significantly (P < 0.05) in specific nutritional properties, including fat, protein, and dietary fiber. White bread, prepared from refined wheat flour, showed the lowest fat (2.40±0.14%) and ash content (1.30±0.14%) along with the highest protein content (8.10±0.14%). Conversely, finger millet bread and multigrain bread contained 7.20±0.14% and 5.40±0.00% protein and 3.20±0.14% and 4.80±0.14% fat, respectively. No significant difference (P > 0.05) was observed in dietary fiber content between multigrain bread (3.40±0.14%) and finger millet bread (3.10±0.14%); however, both were significantly higher (P<0.05) than white bread (2.10±0.14%). The antioxidant activities were 0.13±0.04%, 10.09±0.10% and 7.76±0.46% for white, finger millet and multigrain bread, respectively. The TPC was 3.05±0.39 mg GAE/g for white bread, 3.53±0.05 mg GAE/g for finger millet bread and 4.41±0.00mg GAE/g for multigrain bread, indicating that it was significantly higher (P<0.05) in multigrain bread. Glycemic Index for white, finger millet and multigrain bread were 63.93±8.14 (medium-GI), 53.50±4.81 (low-GI) and 45.78±4.14 (low-GI), respectively. In conclusion, these findings suggest that finger millet and multigrain breads have the potential to serve as healthier bread options for glycemic control and metabolic health in the general population, owing to their lower glycemic impact and higher antioxidant and phenolic content.