Ceylon Journal of Science (Biological Sciences)
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Item Trimen's taxonomy and a revised handbook to the flora of Ceylon(University of Peradeniya. Peradeniya, 1998) Cramer, L.H.Item Cell suspension cultures of Musa. cv embul (AAB), mondan (ABB) and kolikuttu (AAB)(University of Peradeniya. Peradeniya, 1998) Hirimburegama, K.Three explants (shoot tip, anthers and fruit pulp) of three cultivars of Musa were tested for callus production under different culture conditions and for the development of cell cultures from the callus. It was observed that callus is produced from all three explants of the tested cultivars, both in liquid and semi-solid, under different culture conditions. There was a variation in the morphology of callus and the type of cells in culture. It could be revealed that factors, namely, the explant, growth regulators and light affect the cell types in suspesion, irrespective of the cultivar. Shoot tip of all 3 cultivars produced an embryogenic callus an cell cultures while fruit pulp and anthers produced callus and cell cultures with predominantly parenchyma.Item Bioaccumulation of heavy metals in relation to body length of Oreochromis mossambicus(University of Peradeniya. Peradeniya, 1998) Wijesinghe, M.R.; Jayatunga, Y.N.A.; Hewamanne, R.The nature of the relationship between bioaccumulation of heavy metals and body size (length) in Oreochromis mossambicus from Beira Lake and Weras Ganga in the Colombo District of Sri Lanka was inverstigated. The work was carried out during March - July 1995. The organs; muscle, gills, gonad, kidney and liver were investigated. Analysis was done by the x-ray fluorescence method. There was a significant difference (p0.05) in the metal levels in a paricular organ between the different length classes. A positive ans statistically significant correlation with body length was seen for Cu concentration in the kidney in both the Beira Lake and Weras Ganga samples. A significant positive correlation with body length was observed for Zn in the gill and kidney, and for Fe in the muscle and liver, of the Beria LAke sample. For Cd in the muscle, a significant negative correlation with length was observed in the Beria Lake sample. This is noteworthy since the muscle is the tissue that is normally consumed. In the same site there was also accumulation of lead in one of the smaller size classes.Item Physico-chemical characteristics of mosquito breeding habitats in an irrigation development area in Sri Lanka(University of Peradeniya. Peradeniya, 1995) Amerasinghe, F.P.; Indrajith, N.G.; Ariyasena, T.G.Item Some studies on the trawl fishery in the Portugal Bay on the northwestern coastal waters of Sri Lanka(University of Peradeniya. Peradeniya, 1998) Jayawardena, P.A.A.T.; Dayaratne, P.Item A preliminary analysis of the flyingfish fishery off Kandakuliya in Sri Lanka(University of Peradeniya. Peradeniya, 1998) Jayawardane, P.A.A.T.; Dayaratne, P.A preliminary analysis of the flyingfish fishery in Kandakuliya of the Kalpitiya Peninsula is presented. The study is based on a survey carried out during the periods September 1991 to April, 1992 and September 1992 to April 1993. Fishing operations were mainly carried out by 5.0 - 5.5m FRM boats, using small meshed gillnets during the daytime. The mesh mesh size of the gillnets range from 29-48 mm. Fishing operations were limmited to to the region 20-30 km from the shore. Total catch, effort and catch per unit effort (CPUE) showed seasonal variations. Peak catches were observed from November to January. Mean CPUE varied from 110 to 155 kg/boat/day from 1991 to 1993. The total annual production from this fishery is about 1500 MT/year. This fishery is dependent on 9 species of flyingfish of which Hirundichthys oxycephalus contributes up to 46perc. of the catch. Species composition changes seasonallyItem Salinity tolerance at cellular level of some high yielding local cultivars of Oryza sativa (rice)(University of Peradeniya. Peradeniya, 1998) Hiriburegama, K.; Basnayake, R.Five cultivars of rice (Oryza sativa) were tested for salinity tolerance at cellular level. Seed callus of the cultivars (BW 351, AT 354, BG 94-1, AT 402) was developed on Murasinghe and SkooItem Spinal conformation of domesticated Sri Lankan elephants(Elephas maximus maximus)(University of Peradeniya. Peradeniya, 1998) Godagama, W.K.; Wemmer, C.; Ratnasooriya, W.D.The aim of this study was to investigate scientifically whether the five spinal conformations (Types 1 to 5) described for the Burmese elephant (Elephas maximus birmanicus) are also present in the Sri Lankan elephant (Elephas maximus). This was done using 140 domesticated elephants and the GAle's five-description system. The results showed thst the five spinal conformation types described for Burmese elephant are also present in the Sri Lankan elephant. Out of the 140 elephants, 23(16perc.) had type 1, 48 conformation. The five types p=0.001, d.f.=4). Further there was a significant difference (fisher's Exact test; p=0.001, d.f.=4) between the number of male elephantas and female elephants falling into the five different types of spinal conformationItem The body condition of Sri Lankan domesticaded elephants (Elephas maximus maximus)(University of Peradeniya. Peradeniya, 1998) Godagama, W.K.; Wemmer, C.; Ratnasooriya, W.D.The body condition of domesticated Sri Lankan elephants has not been scientifically evaluated although many believe that it is poor. The objective of this study was to evalute the body condition of domesticated elephants in Sri Lanka using an index developed by Wemmer and Krishnamurthy (1992). This method of assessing relies on visual assessment and numerical scoring of six criteria (temporal depression, scapula, thoracic region, flank area, lumbar vertibrae and pelvic bone) resulting in a scale of 0-11. The study was conducted between 1st April 1993 and 1st April 1994 in 13 administrative districts using 140 domesticated elephants. The results show that the mean body condition index of the present day domesticated elephants is 6.95+/- 0.26 points (mean +/- SEM). MAles had significantly lower body condition index (6.63+/-0.22 points) than that of females (7.3+/-0.21points) and there was no significant (r=0.398, p=1, n=140) correlation between the age and the body condition index of elephants. Further, the body condition index was not significantly different between the elephants which were owned by private individuals or temples and dewales (p=0.71) and maintained by the mahouts or the owners(p=0.21)Item Root nodulation and fungal associations of two common herbaceous leguminous weeds in the university of Peradeniya(University of peradeniya. Peradeniya, 1995) Abeyagoonasekera, R.M.K.; Balakrishnan, K.T.