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Feb 2023 DOI 10.14302/issn.2639-3166.jar-22-4389
Haroun Mohamed Adam AbubakerCorresponding author
The greater wax moth (Galleria mellonella L.) is one of the most destructive insect pests that threaten apiculture. Laboratory experiments were conducted in the Research Laboratory, College of Agricultural Studies, Sudan University of Science and Technology during the period from the 2nd_ of April to 29th_ of October 2021 to evaluate the lethal effect of Bee glue (proplis) and Bacillus thuringiensis var. Kurstaki (Btk) on the G.mellonella. Five concentrations (5%, 7.5%, 10%, 12.5% and 15%) of proplis extract and (0.62,1.25,2.5,5 and 10 mg/ml) of Bt were used for each proplis extract and Bt in a Completely Randomized Design. Powder ethanol extract of proplis at 15% concentration caused 83.3% mortality after 96 hrs of application, where as 10mg//ml concentration of Bt gave 93.3% mortality after 72 hrs of exposure. The statistical analysis revealed significant differences between all treatments and control. Additionally, all treatments (proplis/ /Bt) increased the mortality %.
Jun 2021 DOI 10.14302/issn.2639-3166.jar-21-3816
Elamin Elhaj WaleedCorresponding author
Department of Plant Protection, College of Agricultural Studies, Sudan University of Science and Technology, Khartoum State, Sudan.
African bollwormis a worldwide-spread species that shows a high degree of polyphagia and it is considered as one of the main agricultural pests in the world. Laboratory experiments were conducted in the Research Laboratory, College of Agricultural Studies, Sudan University of Science and Technology to evaluate the lethal effect of C. rotundusand D. stramonium on the H. armigeraand to investigate the synergistic effect of sesame oil and tested extracts by dipping methods. Five concentrations (4%, 6%, 8%, 10% and 12%) were used for each plant extract in a Completely Randomized Design. Tubers ethanolic extract of C. rotundus at 12% concentration caused 90% mortality after 72 hrs of application, whereas 12% concentration of seeds ethanolic extract of D. stramonium generate only 70% mortality after 72 hrs of exposure. When sesame oil was added to each concentration of ethanolic extract of C. rotundus and D. stramonium it exhibited a synergistic effect. In fact, the 10% concentration scored 53.3% and 76.7% mortality, however, when mixed with sesame oil the mortality increased significantly to 83.3% and 100% for D. stramonium and C. rotundus respectively after 72 hrs of exposure. This study clearly demonstrates that both tested plants have a lethal effect on the larvae of the African bollworm. However, tubers ethanolic extract of C. rotundus seems to be significantly more toxic than the seeds ethanolic extract of D. stramonium. This study also revealed that sesame oil has a synergistic effect when added to these plant extracts.
Mar 2020 DOI 10.14302/issn.2637-6075.jpae-20-3198
C. Izah SylvesterCorresponding author
Department of Biology, Bayelsa Medical University, Yenagoa, Bayelsa State, Nigeria.
Aminoforce containing 720g/l of 2,4-dimethylamine salt induced changes on some enzymes and electrolytes in the male Oryclotagus cuniculus (New Zealand rabbit) were assayed. The organisms were exposed to varying sub-lethal concentrations of the toxicant (720g/l). The concentrations were prepared by pipetting 0.4mls, 0.8mls and 0.12mls making it up to 1.5L clean water in a metal container to make 2.0 mgl-1, 4.0 mgl-1 and 6.0 mgl-1. Aspartate amino transferase (AST), Alanine amino transferase (ALT) and Acid phosphatase (ACP) were assayed in the liver and blood. Results showed that aspartate amino transferase values in the liver and blood were significant (p<0.05) across the concentration of the toxicants. Aspartate amino transferase increased as the concentration of the toxicant increased in the liver, and decreased as the toxicant concentration increased in the blood. Alanine amino transferase in the blood and liver were akin to AST while ACP values increased in the blood and decreased in the liver as the concentration of the toxicant increased. Electrolytes (Sodium (Na+), potassium (K+) and magnesium (Mg2+) ions) showed statistical deviation across the various concentration of the toxicants. Chloride ion values stabilized in the experimental group being not significantly different (p>0.05) across the various concentration of the toxicants. From the study, AST, ALT and ACP are suitable biomarkers for showing sub-lethal effect of aminoforce on Oryclotagus cuniculus. The effects recorded clearly unveiled the potential effect of this xenobiotics on Oryclotagus cuniculus. Therefore, exposure of Oryclotagus cuniculus to this toxicant will affect the organism’s physiological responses and over prolong period of time it could lead to death. Additionally, via food chain man may be affected. The use of this toxicant close to rabbittory should be done with utmost caution.
Feb 2019 DOI 10.14302/issn.2689-4602.jes-18-2431
F Chadov BorisCorresponding author
Institute of Cytology and Genetics, Siberian Department of Russian Academy of Sciences, Novosibirsk 630090, Russian Federation.
The existing hypotheses on speciation rely on Mendelian genes and mutations in them. However, genome-wide sequencing demonstrates that the Mendelian genes account less than one-tenth of the entire genome DNA. This means that a greater part of the genome has not yet been subject to large-scale evolutionary consideration. This paper deals with the conditional mutations in drosophila, which are mutations of the genes belonging to a special category (ontogenes) controlling the program of individual development. The ontogenes presumably reside in the DNA of intergenic spaces and introns. Conditional mutations display a number of properties absent in the mutations of Mendelian genes. These specific properties allow three key problems in speciation to be solved: (1) the possibility of emergence of new traits as a result of sequential mutagenesis; (2) selection of mutants; and (3) establishment of isolation. We have shown that (1) the mutations in ontogenes are able to form new multigenic regulatory blocks that escape selection during their creation; (2) mutations in ontogenes allow for existence of constantly acting zygotic selection, which is by no means less important for speciation than Darwinian selection; and (3) owing to their conditionally lethal effect, the mutations in ontogenes are able to create biological isolation barrier. This gives the grounds for assuming that the emergence of mutations in ontogenes is a necessary condition for speciation.