Genetic Diversity of Selected Upland Rice Genotypes (Oryza sativa L.) for Grain Yield and Related Traits

Seventy-seven upland rice genotypes including popular cultivars in Nigeria and introduced varieties selected from across rice-growing regions of the world were evaluated under optimal upland ecology. These genotypes were characterised for 10 traits and the quantitative data subjected to Pearson correlation matrix, Principal Component Analysis and cluster analysis to determine the level of diversity and degree of association existing between grain yield and its related component traits. Yield and most related component traits exhibited higher PCV compared to growth parameters. Yield had the highest PCV (41.72%) while all other parameters had low to moderate GCV. Genetic Advance (GA) ranged from 9.88% for plant height at maturity to 41.08% for yield. High heritability estimates were recorded for 1000 grain weight (88.71%), days to 50% flowering (86.67%) and days to 85% maturity (71.98%). Furthermore, grain yield showed significant positive correlation with days to 50% flowering and number of panicles m-2. Three cluster groups were obtained based on the UPGMA and the first three principal components explained about 64.55% of the total variation among the 10 characters. The PCA results suggests that characters such as grain yield, days to flowering, leaf area and plant height at maturity were the principal discriminatory traits for this rice germplasm indicating that selection in favour of these traits might be effective in this population and environment

Physiological responses of cowpea simultaneously exposed to water deficit stress and varying light intensities at vegetative and reproductive growth stages

A combination of stresses as it occurs on the field poses more challenges to crop production than individual stress. Crops’ response to single stress also differs from that of combined stresses. The morpho-physiological responses of two cowpea varieties (IT89KD-288 and IT99K573-1-1) to a combination of stresses (water deficit stress and high light intensity) were investigated at different growth stages. Three levels of light intensities (L3: 259 Lux- 36%, L2: 394 Lux-55% and L1: 710.2 Lux-100%) were imposed using one, two and zero layer(s) of the net, respectively, while, water deficit stress at four levels (W1: no water stress; 0-5 bars, W2: moderate water stress; 5-15 bars, W3: moderately-severe; 15-40 bars and W4: severe water stress; 40 -70 bars) was imposed differently at vegetative and reproductive growth stages. Data were collected on the cowpea yield, Leaf Temperature (LT), Chlorophyll (C), Photosynthesis (P), Stomatal Conductance (SC) and Canopy Transpiration Rate (CTR). Exposure to W4 under L1 considerably reduced cowpea yield by 80% compared to those grown under L3 and full watering. Reduced light intensity enhanced cowpea grain yield irrespective of water deficit stress and IT89KD-288 was superior to IT99K573-1-1. Reduction in light intensity also increased the SC from 55.18 in L1 to 76.88 in 36 % L3. Full light intensity without water stress (100% light intensity), increased C content, while severe water stress reduced the C content and CTR. Photosynthesis was, however, reduced under low light intensity compared to 100% light intensity. It was also observed that water deficit stress imposed at the reproductive stage did not affect P, CTR and SC unlike that of the vegetative stage. In conclusion, reduced light intensity enhanced cowpea tolerance to water deficit and increased yield. Cowpea response was dependent on growth stage, variety and severity of stress

Ophthalmic manifestations in patients with intracranial tumours

Introduction L’étude a pour but d’apprécier les manifestations ophtalmologiques des patients présentant des tumeurs cérébrales au Nigéria dans un hôpital tertiaire. Méthode Il s’agit d’une étude rétrospective avec une revue des tumeurs cérébrales dans le Neurosurgical Unit of Obafemi Awolowo University Teaching Hospitals Complex, Ile- Ife de janvier 2003 à décembre 2007. L’analyse des données, diagnostique, acuité visuelle, et prise en charge, ont été analysées selon la fréquence en utilisant avec la version 1 11 SPCS . L’acuité visuelle a été classifiée selon celle de l’OMS. Résultat Sur un total de 94 patients, 88 patients ont été revus. Il s’agissait de 53 patients de sexe masculin et 35 de sexe féminin. La moyenne d’âge était de 36.2 plus ou moins 20 ans. 14 patients ont été pris en charge par les ophtalmologistes. La répartition des tumeurs était la suivante: méningiomes, 36,4 %, craniopharyngiomes, 13,6 % et gliomes, 9,1 %. 67,9 % des patients se plaignaient de troubles visuels à l’admission dont 46,6 % avec une baisse importante et 12,5 % une vision double. Il a été objectivé une artrophie optique dans 23,9 % . 46 malades (52 %) étaient aveugles et 14 (16 %) avaient un trouble visuelimportant. Conclusion Les troubles visuels sont des manifestations cliniques fréquentes de présentation des tumeurs cérébrales. Une information médicale précoce est requise