http://www.digital.lib.esn.ac.lk//handle/123456789/3696 Tue, 21 Apr 2026 12:42:32 GMT 2026-04-21T12:42:32Z http://www.digital.lib.esn.ac.lk//handle/123456789/3781 COMBINING ABILITY FOR YIELD AND COMPONENT CHARACTERS IN RICE (Oryza sativa L.) Y. Anbuselvam, M. Venkatesan; R. Elangaimannan, P. Karthikeyan Combining ability for ten quantitative and physical characters in rice was studied through Line × Tester analysis involving eight lines and four testers. The mean squares of variance for Line × Tester interaction was significant for all the characters expect grain length and grain breadth. The combining ability analysis revealed non-additive gene action governing the characters viz., days to first flower, plant height, panicles plant-1, grain yield plant-1 and grain L/B ratio. GCA variance predominance over SCA was recorded for days to first flower, plant height, grains panicle-1 and grain yield plant-1. Among the parents, the lines L3 (AD 95137), L4 (AD 95157) and L8 (MDU 5) and testers T2 (ADT 36), T3 (ADT 43) and T4 (IR 50) were good combiners for grain yield and most of the yield component characters studied. Hence, crosses involving these parents were identified as suitable for recombination breeding. Thu, 01 Jan 2009 00:00:00 GMT http://www.digital.lib.esn.ac.lk//handle/123456789/3781 2009-01-01T00:00:00Z http://www.digital.lib.esn.ac.lk//handle/123456789/3780 STANDARDIZATION OF THRESHING AND DRYING METHODS IN HYBRID RICE (Oryza sativa L.) SEED PRODUCTION T. Ramanadane, A.S. Ponnuswamy Studies were conducted to standardize threshing and drying methods of two rice hybrids viz., ADTRH 1 and CORH 2 during 2001-2003. Three threshing methods viz., hand threshing (beaten against the wood), mechanical threshing (commercial multicrop thresher at 600 rpm speed) and tractor treading (tractor was moved over the thick layer of the harvested plants) and six drying methods sun, shade, alternate, intermittent, solar and heated air drying were experimented. Observations on threshing efficiency, seed germination, vigour index, field emergence, electrical conductivity of seed leachate and seed storability were recorded . The results revealed that the threshing efficiency was significantly higher in mechanical thresher followed by tractor treading. The vigour and viability of fresh and stored seeds also indicated that hand and mechanical threshing were better than tractor treading. However, hand threshing may not be economical since it is laborious, more time consuming and low in threshing. Hybrids also differed with quality and retention of filled seeds after threshing. Among the traditional drying methods, alternate, intermittent and shade drying performed better than sun drying whereas between artificial drying methods, heated air drier excelled the solar drier. Seeds dried in alternate and heated air drying methods recorded higher values for all the vigour parameters over other methods. It could be concluded that mechanical threshing is a feasible method to obtain good quality seeds with maximum threshing efficiency and heated air drying at 40 °C is more appropriate for large scale seed production hybrid rice. In the absence of artificial driers, alternate drying method may be adopted. Thu, 01 Jan 2009 00:00:00 GMT http://www.digital.lib.esn.ac.lk//handle/123456789/3780 2009-01-01T00:00:00Z http://www.digital.lib.esn.ac.lk//handle/123456789/3779 Development of Palmyrah Odial Based Breakfast Cereal Mixtures A research was conducted to develop nutritionally value added products using palmyrah odial flour to make the locally produced odial as more palatable and to increase its consumption. The total palmyrah population of Sri Lanka is about eleven million and the potential yield of the flour is around 5000 metric tones per year. As only a small quantity of odial is used for the production of value added products, it is advisable to diversify and make other starch based products. Twelve types of different mixtures, which can be used as a breakfast cereal food were produced using boiled dried palmyrah tuber, rice, maize, sorghum, soybean, green gram, black gram, and sugar as raw materials. By adding different proportions of odial flour, varieties of mixtures were produced and by changing the amount and the combination of the cereals, the differences were created among the treatments. In order to select the best mixture, the nutritional and sensory attributes of the products were evaluated. The findings of this study revealed that all of the products other than the products made by 20% of odial are well suited for the consumption in case of their nutritional attributes. In sensory attributes the product made by rice, maize cereal mixture with 15% odial can be considered as the best. The products made by rice, maize cereal mixture with 10% odial can also be concluded as good in case of consumer acceptance Thu, 01 Jan 2009 00:00:00 GMT http://www.digital.lib.esn.ac.lk//handle/123456789/3779 2009-01-01T00:00:00Z http://www.digital.lib.esn.ac.lk//handle/123456789/3778 PHYSICO-CHEMICAL CHARACTERISTICS OF THE BATTICALOA LAGOON P. Vinobaba The water quality parameters were measured to reveal the present condition of the Batticaloa lagoon. Among the water quality characteristics, physical parameters such as temperature, pH, conductivity, salinity, turbidity and chemical parameters such as dissolved oxygen, nitrate, nitrite, phosphate, sulphate, total iron, and free chlorine were measured. The higher degree of water quality parameter fluctuations were observed in Kattankudy, Urani, and along the agricultural area based lagoon sites, where more chemicals and effluents enter into the Batticaloa lagoon. This study elucidated that the Batticaloa lagoon water parameter change fall within the acceptable level for aquatic organisms living conditions. The water quality parameters of the study sites are given as follows; Temperature 28o C – 34o C; pH 6.64 - 8.06; Salinity 0.00 – 27 PSU; Turbidity 5-94 FAU;Dissolved oxygen 4.5 – 5.9 mg/l; Nitrates 0.01–4.0 mg/l; Nitrites 1 – 13 mg/l; Phosphates 0.11 – 1.68 mg/l; Sulphates 15 – 656 mg/l; Total iron 0.07 – 2.30 mg/l; Free chlorine 0.01 – 0.75 mg/l. The available literature does not fulfill the water quality measures in the Batticaloa lagoon. Only a few reports are available regarding the presence of pollutants in the Batticaloa lagoon. A complete water quality data base is urgently needed to advice the organizations, funding agents and individuals, who are interested in promoting the aquatic food production such as fish, shrimp, crab and oyster farming. At this juncture, it is essential to prevent further pollution and to preserve the uninterrupted ecosystem services for a long lasting future. Thu, 01 Jan 2009 00:00:00 GMT http://www.digital.lib.esn.ac.lk//handle/123456789/3778 2009-01-01T00:00:00Z