Absent Left Main Coronary Artery with Variation in the Origin of its Branches in a South African Population          下载免费PDF全文

N. O. Ajayi  L. Lazarus  E. A. Vanker  K. S. Satyapal 《Anatomia, histologia, embryologia》2015,44(2):81-85

Coronary artery anomalies are traditionally classified into anomalies of origin, course and termination. One of the anomalies of origin is absence of the left main coronary artery (LMCA), where the left anterior descending (LAD), the circumflex (Cx) and the ramus medianus (RM) (when present) arteries originate directly from the left aortic sinus. The study aimed to document the prevalence of absent LMCA, discuss its possible embryogenesis and clinical relevance. A review of 407 coronary angiograms performed by cardiologists of three private hospitals in the eThekwini Municipality area of KwaZulu‐Natal, South Africa, was performed. The LMCA was absent in 9.6% (39/407) of the coronary angiograms. The LAD and Cx arteries originated directly from the left aortic sinus with a single ostium in 8.6% (35/407) and separate ostia in 1% (4/407) of the angiograms. In four of the angiograms with absent LMCA, a RM artery was recorded originating directly from the left aortic sinus in addition to the LAD and the Cx arteries. Angiographic detection of the anomalies of the coronary arteries is essential in the determination of the significance of such findings and their management.  相似文献   

Research-Extension-Farmer-Input Linkage System for Better Communication and Uptake of Research Results in Nigerian Rural Agriculture     

H. F. B. Faborode  A. O. Ajayi 《Journal Of Agricultural & Food Information》2013,14(1):80-96

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Jaundice syndrome in African sharp‐tooth catfish,Clarias gariepinus (Burchell), associated with haemolytic Staphylococcus aureus     

O O Oladele  O L Ajayi  O O Olude  O O Stephen  A A Adediji  I O Arasi  U G Ntiwunka 《Journal of fish diseases》2012,35(12):945-947

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Strength attributes and compaction susceptibility of Brazilian Latosols     

Ayodele Ebenezer Ajayi  Moacir de Souza Dias Junior  Nilton Curi  Cezar Francisco Araujo Junior  Thiago Tadeu Teixeira Souza  Alberto Vasconcellos Inda Junior 《Soil & Tillage Research》2009,105(1):122-127

In this study, strength attributes and compaction susceptibility of the main classes of Brazilian Latosols (Oxisols), under native vegetation, were studied using the load bearing capacity models relating precompression stress, compression index and water potential through statistical regression models. These models were developed based on the results of the analysis of undisturbed soil samples collected at the B horizon at the different sites. The results showed that the maximum value of the compression index was 0.53 for the Acric Red Latosol, indicating its higher susceptibility to soil compaction. The Dystrocohesive Yellow Latosol had the highest load bearing capacity, while the Acric Red Latosol had the lowest one. The Dystrocohesive Yellow Latosol due to its high load bearing capacity and bulk density (mechanical resistance) behave similarly to hardsetting soil, in which the plants root system has severe physical restrictions to explore deeper horizons during the dry periods. Differences in the load bearing capacity and compaction susceptibility were found to be influenced by soil structure which is associated with clay mineralogy in these very weathered-leached soils and water potential. The study also showed that soil compression index is influenced by water potential and clay mineralogy also. Our work has laid a foundation for estimation of compaction susceptibility of Latosols.  相似文献   

Rhizoctonia solani: taxonomy,population biology and management of rhizoctonia seedling disease of soybean          下载免费PDF全文

O. O. Ajayi‐Oyetunde  C. A. Bradley 《Plant pathology》2018,67(1):3-17

Rhizoctonia solani, the most important species within the genus Rhizoctonia, is a soilborne plant pathogen with considerable diversity in cultural morphology, host range and aggressiveness. Despite its history as a destructive pathogen of economically important crops worldwide, our understanding of its taxonomic relationship with other Rhizoctonia‐like fungi, incompatibility systems, and population biology is rather limited. Among the host of diseases it has been associated with, seedling diseases inflicted on soybean are of significant importance, especially in the soybean growing regions of North America. Due to the dearth of resistant soybean genotypes, as well as the paucity of information on the mechanisms of host–pathogen interactions and other molecular aspects of pathogenicity, effective management options have mostly relied upon a combination of cultural and chemical control options. The first section of this review summarizes what is currently known about the taxonomy and systematics, population biology and molecular genetics of R. solani. The second section provides an overview of the pathology and management of rhizoctonia root and hypocotyl rot of soybean, a seedling disease of importance in North America.  相似文献   

Effect of organic fertilizer on the growth and fruit yield of six paprika (<Emphasis Type="Italic">Capsicum annum</Emphasis> L.<Emphasis Type="Italic">)</Emphasis> cultivars in Malawi     

Gudeta W. Sileshi  Festus K. Akinnifesi  France M. Gondwe  Oluyede C. Ajayi  Simon Mng’omba  Konisaga Mwafongo 《Agroforestry Systems》2011,83(3):361-372

The production of paprika (Capsicum annum L.) under small-scale farm conditions in southern Africa is constrained by low soil fertility and lack of appropriate cultivars. The objective of this study was to determine the growth responses and fruit yields of six cultivars of paprika to organic and inorganic nutrient sources. The study was conducted in 2007 and 2008 at Chitedze Agricultural Research Station in Malawi. A combination of six paprika cultivars and four nutrient sources, namely (1) organic input from Gliricidia, (Gliricidia sepium) biomass, (2) inorganic fertilizer, (3) integrated nutrient input (Gliricidia biomass + inorganic fertilizer), and (4) control (no nutrient input) were compared. Each combination was replicated five times. A split-plot design was used where nutrient sources formed the main plot and cultivars the sub-plots. Plant height differed due to nutrient source in 2007 and 2008, while differences due to cultivar were minor. The control plots produced the shortest plants (height < 50 cm), while plots receiving the integrated nutrient input produced the tallest plants (height > 60 cm). Numbers of branches and fruits per plant differed due to nutrient source and cultivar during most of the study period. Plants receiving either organic inputs (Gliricidia biomass) alone or the integrated nutrient input alone had significantly higher stem, leaf and fruit weight compared with the control. Average fruit yield was lower in control plots than in plots receiving the organic input alone or the integrated nutrient input. Among cultivars, Papri-King, Papri-Supreme and Papri-Queen produced higher dry fruit yield. The ASTA and RAL colour rating was within the internationally accepted range for fruit from the treatments.  相似文献   

Certification of agroforestry tree germplasm in Southern Africa: opportunities and challenges     

B. I. Nyoka  O. C. Ajayi  F. K. Akinnifesi  T. Chanyenga  S. A. Mng’omba  G. Sileshi  R. Jamnadass  T. Madhibha 《Agroforestry Systems》2011,83(1):75-87

The lack of high quality agroforestry tree germplasm has long been recognized as one of the major challenges to widespread adoption of agroforestry in Southern Africa. Productivity levels realized in operational scale plantings are far less than those demonstrated in research and this has been partly blamed on the use of germplasm of unknown quality and low productivity potential. The lack of high quality germplasm is attributable to the absence of regulations to govern its production in the countries promoting agroforestry. Most of the agroforestry tree germplasm is sold or distributed without regard to its genetic, physiological and physical quality. Given these challenges, in this paper, we reviewed crop seed certification in general and tree germplasm certification in the USA, Europe, India, Southern Africa and the Organisation for Economic Cooperation and Development (OECD) with a view to find potential similarities with agroforestry tree germplasm. Only three countries in sub-Saharan Africa (Burkina Faso, Madagascar and Rwanda) were found to have tree germplasm certification: the OECD Forest Seed and Plant certification scheme. From the review, it is possible to establish agroforestry tree germplasm quality control systems, more so in countries that already have tree seed centres and tree seed regulations. A simple agroforestry tree germplasm certification scheme, based on the FAOs Quality Declared Seed (QDS) with truth-in-labelling is recommended. Three germplasm categories (audit, select and genetically improved) are recommended as a start. Furthermore, countries will need to develop new or amend existing agricultural seed policies and regulations to include agroforestry tree germplasm certification under QDS. Finally, germplasm quality standards for the selected agroforestry trees species in the respective countries will need to be developed.  相似文献   

Farmers’ choice of genotypes and trait preferences in tropically adapted chickens in five agro-ecological zones in Nigeria     

Yakubu  A.  Bamidele  O.  Hassan  W. A.  Ajayi  F. O.  Ogundu  U. E.  Alabi  O.  Sonaiya  E. B.  Adebambo  O. A. 《Tropical animal health and production》2020,52(1):95-107

This study aimed at determining chicken genotypes of choice and traits preference in chicken by smallholder farmers in Nigeria. Data were obtained from a total of 2063 farmers using structured questionnaires in five agro-ecological zones in Nigeria. Chi square (χ²) statistics was used to explore relationships between categorical variables. The mean ranks of the six genotypes and twelve traits of preference were compared using the non-parametric Kruskal–Wallis H (with Mann–Whitney U test for post hoc separation of mean ranks), Friedman, and Wilcoxon signed-rank (with Bonferroni’s adjustments) tests. Categorical principal component analysis (CATPCA) was used to assign farmers into groups. Gender distribution of farmers was found to be statistically significant (χ²?=?16.599; P?≤?0.002) across the zones. With the exception of Shika Brown, preferences for chicken genotypes were significantly (P?≤?0.01) influenced by agro-ecological zone. However, gender differentiated response was only significant (P?≤?0.01) in Sasso chicken with more preference by male farmers. Overall, FUNAAB Alpha, Sasso, and Noiler chicken were ranked 1st, followed by Kuroiler (4th), Shika Brown (5th), and Fulani birds (6th), respectively. Within genotypes, within and across zones and gender, preferences for traits varied significantly (P?≤?0.005 and P?≤?0.01). Traits of preference for selection of chicken breeding stock tended towards body size, egg number, egg size, and meat taste. Spearman’s rank order correlation coefficients of traits of preference were significant (P?≤?0.01) and ranged from 0.22 to 0.90. The two PCs extracted, which explained 65.3% of the variability in the dataset, were able to assign the farmers into two groups based on preference for body size of cock and hen and the other ten traits combined. The present findings may guide the choice of appropriate chicken genotypes while the traits of economic importance may be incorporated into future genetic improvement and conservation programs in Nigeria.

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Agroforestry Tree Seed Production and Supply Systems in Malawi   总被引：1，自引：1，他引：0  

Betserai I. Nyoka  Simon A. Mng��omba  Festus K. Akinnifesi  Oluyede C. Ajayi  Gudeta Sileshi  Ramni Jamnadass 《Small-Scale Forestry》2011,10(4):419-434

A sustainable agroforestry tree germplasm supply system is vital to resource-constrained smallholder farmers who depend on agroforestry to improve the productivity of their farm enterprises. Successful adoption of agroforestry hinges on the development of a sustainable agroforestry tree germplasm supply system. This paper reviews the agroforestry tree seed supply system in Malawi, with a view to determining its sustainability and quality. Currently, more than 90% of the documented agroforestry tree seed distributed to farmers is produced by smallholder farmers collected mainly from scattered farmland trees, the remainder being produced from seed orchards and seed stands owned or controlled by research organizations. Three organizations—namely the Land Resources Centre (LRC), National Tree Seed Centre (NTSC) of the Forestry Research Institute of Malawi (FRIM) and the World Agroforestry Centre (ICRAF)—were identified as major procurers of agroforestry tree seed produced by smallholder farmers. Agroforestry germplasm is distributed to farmers by non-governmental organizations (NGOs) and government agricultural and forestry extension departments. The procurement and distribution of germplasm to farmers is in general effective. The major challenge to sustainability of agroforestry tree germplasm distribution in Malawi is dependence on donor funding. The agroforestry tree seed system is, to some extent, sustainable with regards to production, although the genetic quality of the germplasm is low. Germplasm storage facilities at national level are available and possibly adequate, but knowledge and information on effective low-cost tree germplasm storage systems at household level are limited. Sustainability could be enhanced by strengthening of grass-root organizations involved in tree seed production to institutionalize the distribution through farmer–farmer exchange. There is also a need to support the development, promotion and adoption of low-cost tree germplasm storage facilities by smallholder farmers.  相似文献   

Effect of replacements of fishmeal and fish oil on growth and dioxin contents of rainbow trout     

Aung Naing OO  Shuichi Satoh  Nen Tsuchida 《Fisheries Science》2007,73(4):750-759

Eight experimental diets were prepared to determine the effect of replacements of fishmeal and fish oil with plant protein and palm oil on the growth and dioxin contents in rainbow trout. The first four diets (FP0, FP5, FP10, and FP15) included fishmeal (55%) with increasing replacement of fish oil by palm oil (0, 5, 10, and 15%). Four other diets (AP0, AP5, AP10, and AP15) were substituted with an alternative protein source and with increasing palm oil content (0, 5, 10, and 15%). Dietary dioxin contents increased as fish oil level increased. Thirty rainbow trout (mean weight 38 g) were fed the experimental diets for 12 weeks. No significant differences in growth performance and feed utilization were observed. Dietary dioxin contents influenced the dioxin contents in the whole body. These results suggest that palm oil could effectively replace fish oil in rainbow trout diets, and reduce the dioxin contents in fish.  相似文献