Efficacy of plant extracts in the control of rodent infestations and their effects on the nutritional contents of sweet potato tuber

The use of plant extracts has been described as credible alternative to synthetic insecticides in the protection of field crops. This research work was conducted at Teaching and Research Farm, Ladoke Akintola University of Technology during the planting seasons of 2015 and 2016 to determine the efficacy of plant extracts – Tephrosia vogelii, Moringa oleiferia, Petiveria alliacea and Annona squamosa in the control of rodent infestation. The experiment was arranged in a randomized complete block design and each treatment was replicated three times. Synthetic insecticide (Lambdachyalothrin) and control were included in the experiment for comparison. Data were collected on plant stands attacked, vine length, yield and nutritional components of sweet potato tuber. The result showed that plant extracts treated sweet potato plants had significant lower rodent infestations when compared with unsprayed plant stands. Also, applied treatments had no negative effect on the vine length meanwhile yield obtained from botanical insecticides treated plants was two times higher than that of untreated plants which had the least tuber yield (0.90 t/ha). The tested plant extracts significantly improved the proximate contents of the harvested sweet potato tubers. Therefore, these plant extracts can be used in the field management of rodent infestation without any adverse effects on the nutritional components of the sweet potato tuber

Characterization of biofilm formation in clinical urinary isolates of Staphylococcus aureus from five hospitals in Lagos State, Nigeria

Background: Biofilm formation by pathogens is of great clinical importance as it mediates persistence and resistance to antibiotics, hence posing difficulty in treatment and management of diseases. The aim of this study was to evaluate the biofilm forming potential of Staphylococcus aureus isolated from urine samples of females with urinary tract infection and to detect the presence of clumping factor (clfA) and intracellular adhesion (icaA) encoding genes.Methodology: A total of 50 S. aureus were obtained from urine samples of women in five hospitals in Lagos State, Nigeria. Isolates were confirmed by standard biochemical and novobiocin susceptibility tests. The isolates were screened for biofilm formation using three methods; Congo-red agar (CRA), tube, and tissue culture plate (TCP) methods. Detection of clfA and icaA genes was done by PCR.Results: The Congo red agar method showed that 39 (78%) of the isolates were biofilm producers while 11 (22%) were non-biofilm producers. However, the tube method indicated that 12 (24%) were strong biofilm producers, 26 (52%) were moderate biofilm producers, and 12 (24%) were non-biofilm producers. The standard TCP assay showed that strong biofilm producers (OD > 0.240) were 13 (26%), moderate biofilm producers were 22 (44%), and weak or non-biofilm producers (OD < 0.120) were 15 (30%). The tube method showed a good correlation with the TCP method for strong biofilm production. Ten (20%) isolates possessed clfA gene and 31 (62%)possessed icaA gene.Conclusion: The ability of S. aureus to form biofilm is a key risk factor that can increase morbidity and mortality from infections they cause. Hence, rapid and sensitive phenotypic methods can be used in screening for biofilm formation thereby providing data that can guide therapy and control of the pathogen. Keywords: Staphylococcus aureus, Biofilm, Clumping factor, Intracellular adhesio

Efficacy of botanical insecticides on insect infestation and fruit yield of eggplants (Solanum melongena L.) in Ogbomoso, Oyo State, Nigeria

Field trials were conducted during 2016 and 2017 raining seasons at the Teaching and Research Farm, Ladoke Akintola University of Technology, Ogbomoso, to determine the effects of leaf extracts of Pawpaw, Tobacco and Cashew leaves on insect pests of three selected eggplant varieties (Solanum depressum; Solanum escullantum and Solanum serpentium). Synthetic insecticide (Lambda-cyhalothrin) and untreated plants were included in the experiment for comparison and each treatment was replicated three times at 20% v/v. The experiments were laid out in Randomized Complete Block Design. Data were collected on insect pests variations and fruit yield. Four major insect pests of eggplant – Zonocerus variegatus, Spodoptera litoralis, Leucinodes ornabalis and Epilachna species were observed. Among the tested varieties, S. depressum had the least significant (P< 0.05) infestation (6 - 13%). All the tested leaf plant extracts were effective in the control of the observed insect pests when compared with the level of insect pest attack on untreated plants. However, cashew extract had highest insecticidal efficacy (55%) compared with other tested plant extracts while insecticidal potential of pawpaw extract was comparable to tobacco extracts. Meanwhile, none of the tested plant leaf extracts was as effective as Lambda-cyhalothrin in the control of the observed insect pests. Among the tested varieties, Solanum depressum had highest fruit yield (3.45 - 3.88 t/ha) and least fruit damage