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Reliable and reproducible protocols to get healthy and well formed plants from juvenile explants of the pomegranate (Punica granatum L.) cv. 'Kandhari Kabuli' have been developed. Calli were initiated from cotyledon, hypocotyl, leaf and internode sections excised from 30 days old in vitro germinated seedlings. The best media for callus induction from cotyledon, hypocotyl, internode and leaf explants were MS medium supplemented with 13.0 ^M NAA and 13.5 ^M BA, 13.0 ^M NAA and 18.0 ^M BA, 5.0 ^M IBA and 9.0 ^M BA, 8.0 ^M NAA and 9.0 ^M kinetin, respectively. The highest percentage of callus was obtained from cotyledon explants (85.50) followed by hypocotyl (79.67), internode (79.47) and leaf (75.48) explants. The calli thus obtained showed differentiation on MS medium supplemented with 9.0 ^M BA and 2.5 ^M NAA. Cotyledon derived callus showed the highest regeneration rate (81.97%, with mean number of 16.47 shoots per explant) followed by hypocotyl, internode and leaf derived calli. In vitro rooting was best on half strength MS medium containing 500 mg l-1 of activated charcoal. The plantlets with well formed root systems were transferred to plastic cups containing cocopeat followed by transfer to earthen pots containing soil and sand (1:1).
The genus Eulophia embraces over 230 species distributed through the tropical and subtropical Africa, Asia, Australia and the Americas. In Neotropics it is represented by a sole species – E. alta. The aim of the presented study was to evaluate the difference between ecological niches occupied by American and African populations of this species based on the ecological niche modeling. The similarity between the glacial and present niches occupied by E. alta was calculated and the factors limiting the species occurrence were identified. Areas of seasonal tropical forest, tropical savanna and woodland served as refugia for the studied species during last glacial maximum and they were more widespread in Neotropics than in Africa. No significant niche shift after last glacial maximum was observed. The distribution of E. alta in its whole range is restricted mainly by temperature seasonality. The differences in the niches occupied by African and Neotropical populations of E. alta suggest preglacial disjunction of the species range and independent adaptation of both groups. Despite the significant range disjunction of E. alta the species is characterized by relatively high degree of niche conservatism.
Malaria is wide spread in poor world and its burden has been assessed by the enumeration of malarial parasites in blood of patients. This study was designed to find a relationship between social structure, and spread of malaria in Khyber agency. The average parasite density was 2050 parasite/μl in Khyber Agency. Due to economic and social setup most of the people have habit of sleeping in open air thus playing role in high malaria prevalence and Plasmodium vivax remains the prevalent species. Genetic study performed on 110 Blood samples showed less genetic diversity for both Plasmodium vivax and Plasmodium falciparum. Eight alleles were distinguished both for Pvmsp 3α and Pvmsp 3β in total of 20 and 39 amplified samples of P. vivax respectively. Out of 17 samples amplified for P. falciparum 11 showed genotype K1 and 10 for MAD at Pfmsp-1 while 14 alleles were identified for 3D7/1C and two for FC27 of corresponding families of Pfmsp-2 gene. This shows that Plasmodium parasites are not genetically diverse in Khyber agency.
The present study describes a new species, Ligophorus uruguayense, parasitizing the gills of Mugil platanus Günther, 1880 from the coast of Uruguay. It differs from all other species of the genus mainly in the shape of the ventral bar, the thick process at the distal end of the inner root of ventral anchors, the J-shaped penis accessory piece and the vaginal tube showing transverse annulations at its distal end, the host species, and geographical distribution. This is the first description of a species of Ligophorus from a mullet in the South Atlantic Ocean.
The anthropogenic effect on faecal and chemical pollution at Bahir Dar Gulf of Lake Tana, Ethiopia was investigated in the period of October 2006 to February 2007. Faecal and physicochemical pollution levels were significantly increased and clearly discernible in the Bahir Dar Gulf locations as compared to presumptively anthropogenic uninfluenced reference locations near the outlet of the Blue Nile River of Lake Tana. One directly sewage influenced lake site at Bahir Dar Gulf was found to be excessively faecally polluted. The total pooled data set from the study for faecal coliforms, Escherichia coli and Clostridium perfringens spores ranged from not detectable (n.d.) to log 6.2 CFU, n.d. to log 6.1 CFU and n.d. to log 1.7 CFU per 100 ml, respectively. A high variation was also observable for the physicochemical parameters including the spectral absorption coefficient at 254 nm, ammonia, nitrite, nitrate, total dissolved solids, total suspended solids and pH values. Although the data have to be considered preliminary, it strongly points to the need for systematic water quality monitoring of Lake Tana and its potential impact sources. This is all the more important as the lake is the largest freshwater body in the country serving a multipurpose role and being identified as a growth corridor of the country.
The study of tree-hole breeding mosquitoes was carried out in the tropical rainforest of Imo State Nigeria (two rural areas and two forest reserves in some parts of Orlu Senatorial Zone) between May – October 2002. Using standard entomological procedures, two macrohabitats (natural tree-holes and bamboo traps) and two microhabitats (leaf axils of cocoyams/pineapples and leaf axils of plantain/banana) were sampled for various mosquito species. Mosquitoes were recovered from all the various biotypes sampled. Types of mosquitoes species encountered, their relative abundance, as well as genera varied signifi cantly during the study (p<0.05). Four genera of mosquitoes: Aedes, Culex, Anopheles and Toxorhynchites were recovered while 16 species of mosquitoes encountered include: Aedes aegypti, Ae. africanus, Ae. simpsoni, Ae. albopictus, Ae. stokesi, Ae. taylori, Ae. apicoargenteus, Culex quinquefasciatus, Cx. nebulosus, Cx. trigripes, Cx. decens, Anopheles gambiae, An. funiestus, An. coustani and Toxorhynchites viridibasis. Most of the mosquitoes showed oviposition preferences for one or more habitats. The presence of Ae. africanus, Ae. simpsoni and Ae. aegypti indicate that the study areas were at risk of yellow fever epidemic. The presence of Anopheles and Culex species ensured endemicity of malaria and fi lariasis, while the recovery of Ae. albopictus in this region suggests a possible outbreak of dengue fever in future if not properly controlled.
Reliable determination of hookworm nematode parasite species from dogs can be carried out post-mortem by microscopical examination of the buccal cavity of adult worms isolated from the host small intestine. In order to allow a proper diagnosis of the hookworm infection in a living host, we developed a polymerase chain reaction (PCR). Using DNA extracted from hookworm eggs and an oligonucleotide set designed on the basis of the DNA sequence of a cysteine proteinase AcCP1 gene, Ancylostoma caninum and Uncinaria stenocephala DNA can be discriminated from each other.
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