Open Access Short Research Article
Aims: The present study aimed to evaluate the role of natural abundance of the ectoparasitoid D. isaea as biological control agent.
Place and Duration: Alzawia region, Libya from March to June 2014.
Methodology: Fifty tomato leaflets infested with L. trifolii Burgess were taken from each greenhouse. Samples were kept in plastic bags and examined in the laboratory. Number of living L. trifolii Burgess larvae, immature stages of the D. isaea walker and number of killed larvae according to feeding (no ovipositon) were counted and recorded.
Results: D. isaea walker recorded two peaks of abundance in all studied greenhouses, the highest peaks recorded 23, 41, 32 and 33 individuals/ 50 infested leaflets in greenhouses 1,2,3 and 4, respectively. The highest average numbers occurred in April in all greenhouses recording 17.3±4.5, 26.4±11.5, 23.8±6.4 and 21.3±8.8 individuals/ 50 infested leaflets in greenhouses 1,2,3 and 4, respectively. On the other hand the percentage of parasitism ranged between 26.4±8.2 and 52.4±6.7% recording its highest numbers in June in greenhouses 1,2 and 3 recording (49.4±11.9%, 50.6±5.5, 52.4±6.7) respectively and 40.3±5.2% in green house 4 in May. The percentage of killed larvae according to host-feeding recorded its highest monthly average numbers in May in greenhouses 1 and 2 recording (44.6±18.9 and, 38.2±2.5), in April in greenhouse 3 recording (29.4±3.3) and in may in greenhouse 4 recording 26.6± 20.5%.
Conclusion: The parasitoid showed low populations in March then, developed good populations that kept the populations of the serpentine leaf miner L. trifolii Burgess at low densities till the end of the season in all studied greenhouses. So no chemical control measurements against L. trifolii Burgess should be applied at the high populations of this parasitoid.
Open Access Short communication
Aims: Diethyl phthalates an example of phthalates which are a group of multifunctional chemicals is one of the most frequently used phthalates for manufacturing numerous products. Its persistence in the waterways could cause metabolic changes in fishes. The present investigation was undertaken to evaluate the changes induced by DEP intoxication in fish antioxidant in fish system.
Study Design: Complete randomized design was used.
Place and Duration of Study: Department of Zoology and Environmental Biology, wet laboratory and the experiment lasted for 21 days.
Methodology: One hundred and twenty fish were randomly divided into four treatment groups (A-D) in 25litre glass aquarium filled to 20 litres mark with aerated deep well water. The fish were subjected to sub lethal concentrations of DEP (0.01 ug/L, 0.03 ug/L and 0.05 ug/L) in a renewal bioassay system. Superoxide dismutase (SOD), catalase (CAT), Glutathione peroxidase (GPx), Lipid peroxidation (LPO) and total protein activity of liver and kidney was assayed in DEP exposed C. gariepinus.
Results: It was observed that DEP significantly lowered (P<0.05) CAT, SOD and GPx activity in the entire organ except LPO and total protein that had significantly (P<0.05) increased activity in all the organs at different concentrations of DEP. It can be elucidated that at different concentration of DEP, oxidative stress, total protein and antioxidant enzyme system on C. gariepinus was significantly disturbed.
Conclusion: DEP has being seen to cause alterations in antioxidant, lipid peroxidation and total protein of C. gariepinus. Therefore, there is need for more studies in the oxidative stress, antioxidant status, and biochemical alterations by DEP to fish species.
Open Access Original Research Article
Aims: The degradation of phenothiazine with the filamentous fungus Beauveria bassiana was studied under different fermentation conditions. The objective was to demonstrate methods to increase substrate conversion in wild type B. bassiana using phenothiazine as a screening substrate. A bio catalytic system was optimized to increase the conversion of phenothiazine by resting cell reactions.
Methodology and Results: Reactions were carried out with cells grown in different concentrations of glucose, 5 - 40 g/L, and different resting cell densities, 0.78-6.2 mg cdw/mL. The conversion was monitored with gas chromatography and was characterized by mass spectroscopy, chiral HPLC, and NMR. The highest conversion, 74%±1, was achieved with 0.78 mg cdw/mL. Glucose didn’t have an effect over the conversion of phenothiazine. This fungus oxidized phenothiazine into its sulfoxide and hydroxyl metabolites.
Conclusion: B. bassiana degrades more phenothiazine at lower cell densities than higher densities. The success of this project helps us expand the oxidation capacity of B. bassiana as a fungal biocatalyst while improving its utility for industrial purposes.
Open Access Original Research Article
Lack of fingerlings is still hampering aquaculture development in Sub-Saharan Africa. African catfish Clarias gariepinus do not have developed stomach at onset of exogenous feeding. Absence of fully developed digestive system at onset of larval exogenous feeding makes catfish unable to utilize dry diets. Introduction of phytogenic feeds that possess naturally occurring hormone could be helpful in enhancing catfish ability to utilize dry feeds. Consequently we made six novel diets comprising entirely of phytogenic ingredients, labeled feed 1 (F1) to feed 6 (F6). The percentage compositions of the experimental feeds were; F1, 100% lettuce seed meal; F2, 100% pawpaw leave meal; F3 100% neem seed meal; F4, (50:50) Lettuce seed meal: pawpaw leaves meal; F5, (50:50) pawpaw leaves meal:neem seed meal and F6, (50:50) Lettuce seed meal: neem seed meal. The control diet F7, was decapsulated artemia. There were three replicates aquariums per treatment diet and first feeding larvae were fed with the diets for fifteen days to examine dietary effects through larval and post larval periods. Larval African catfish were produced through artificial fertilization and stocked at 100 larvae 10 liters-1 aquarium. The larvae fed with F1 had the F6 had the highest SGR of 10.12% day-1 followed by SGR of larvae fed with F5 8.27% day- and F2, 8.02% day-1. Larvae fed with F3 and F4 had similar SGR but higher than those fed with F1. The larvae fed with feed 7 and F6 had similar weight gain that was significantly better than others (P<0.05). The larvae fed with Feed F5 and F2 had similar weight gains but were better than those fed with F1, F3 and F4. Survival of larvae seems to be enhanced by inclusion of lettuce in diets of larvae Africa catfish. The survival the larvae fed with F1 was approximately 27% while survival of larvae fed with F6 was next with survival rate of 21%. The larvae fed with F3 had survival rate of 18%, which was different from F1 fed larvae. The least survival rate was noted for larvae fed with F4. Results indicate that phytogenic feeds exert significant effects on the survival, growth and weight gain of first feeding African catfish larvae. Catfish seem to benefit from natural phytogenic components of the plant diets. Feeds like lettuce seed and its combinations produced similar larval growth rate as using artemia alone.
Open Access Original Research Article
Aims: Investigate the genetic diversity and structure of 50 Sorghum accessions from 10 different regions in Sudan and one from the county of Central Equatoria in the Republic of South Sudan, by screening 40 RAPD and 10 ISSR (Inter-simple sequence repeat) markers.
Study Design: UPGMA method using STATISTCA- SPSS software Ver. 9 and PCA using GenAlEx ver. 6.5
Place and Duration of Study: Department of Molecular Biology, Commission for Biotechnology and Genetic Engineering, National Center for Research, Khartoum, Sudan (2010-2012).
Methodology: 47 sorghum accessions with important agronomic traits, representing 10 states in Sudan and three sorghum accessions from the county of Central Equatoria of Republic of South Sudan were assayed for polymorphism using Random Amplified Polymorphic DNA (RAPD) and Inter-simple sequence repeats (ISSRs).
Results: Ten polymorphic RAPD primers distinguished 163 bands. 156 bands were polymorphic among the 50 accessions with 96.6% polymorphism. The seven polymorphic ISSR primers distinguished 78 bands, of which 75 bands were polymorphic with 97% polymorphism. The RAPD distance matrix ranged between 0.07-0.43 which proved wide range of variation, ISSR distance matrix ranged between 0.04-0.47 showing higher genetic variability among the sorghum accessions than the RAPD, whereas, combined data distance matrix for both RAPD and ISSR markers ranged between 0.08-0.39 which reflected more trusted result among Sudanese sorghum accessions. The White Nile state accessions showed the highest percentage of polymorphic loci with 39.75%, whereas lowest was given by Red Sea accessions with 17.99%. The molecular variance within states was 70% and 30% among states.
Conclusion: In conclusion, Results based on combined analysis of both RAPD and ISSR data were most accurate for covering large area inside the genome. White Nile state accessions was the highest in number of bands; number of private bands; percentage of polymorphic loci and heterozygosity (He) mean compared to accessions of other states.