Full Text Available
Access Repository
Search Results - Genetic main
- Go to Previous Page
- Showing 21 - 21 results of 21
-
BIOSYSTEMATIC STUDIES IN SOME NIGERIAN SPECIES OF ANTHERICUM LIN. AND CHLOROPHYTUM KER-GAWL. (LILIACEAE)
Published 1981-03Call Number: Loading…
Located: Loading…Thesis Loading…
Search Tools:
Refine Results
Page will reload when a filter is selected or excluded.- Asejire Lake 2 results 2
- Combining ability 2 results 2
- Cowpea radio-sensitivity 2 results 2
- Gamma irradiated cowpea seed 2 results 2
- Grain yield 2 results 2
- Mutant phenotypes 2 results 2
- Pollen mutagenesis 2 results 2
- Ultra-violet irradiated pollen 2 results 2
- Amaranth is an underutilised crop with great potential as a source of essential nutrients. It also contains bioactive compounds with potential health benefits. However, its characterisation for agronomic and nutritional traits is limited. Likewise, information on its hepatoprotective potential is scarce. In this study Amaranthus accessions were characterised using phenotypic and molecular markers. The quality of its seed protein and hepatoprotective activity of its Ethanol Seed Extract (ESE) on sodium arsenite (NaAS)-induced toxicity in male rats were also investigated. Twenty-nine accessions (27 from the United States Agricultural Research Station and 2 from National Horticultural Research Institute, Ibadan) were characterised using 27 phenotypic traits and 16 Random Amplified Polymorphic DNA (RAPD) primers. Protein quality was assessed using Kjedahl method, amino acid analyzer and one-dimensional electrophoresis. The ESE of all accessions were analysed for phytochemical contents and antioxidant activities. Two out of the 29 accessions with the highest nutritional contents were used for hepatoprotective study. Experimental design consisted of two main groups (representing the two accessions), each consisting of eight treatment groups of 5 rats each. Treatment groups comprised of control, NaAS (2.5mg/kg body weight), amaranth seed extracts (100, 200, 300 mg/kg body weight) and NaAS plus amaranth seed extracts (100, 200, 300 mg/kg). After 14 days of treatment, serum Alanine Aminotransferase (ALT) and Gamma Glutamyl Transferase (GGT) activities were assayed spectrophotometrically. Hepatic Superoxide Dismutase (SOD), Catalase and Glutathione Peroxidase (GPx) activities were assayed likewise. Data were analysed using ANOVA and Cluster at p=0.05. For phenotypic traits, 57.5% variability was observed and accessions were grouped into five clusters. The RAPD analysis yielded 193 loci. Genetic similarity coefficient ranged from 0.6 to 0.9 while dendogram grouped accessions into nine clusters. Total protein contents ranged from 11.8 to 19.0%. Total essential amino acids ranged from 31.2 to 44.9% and were limited in tryptophan and leucine. Albumin, globulin and glutelin were the major protein fractions. Phytate, total flavonoid, total polyphenol, 2, 2-diphenyl-1-picrylhydrazyl (DPPH), total antioxidant and 2, 2-azino-bis-3-ethylbenz-thiazoline-6-sulfonate (ABTS) values ranged from 0.8-1.9%; 7.8-11.0mg/100g; 23.9-35.4mg/100g; 82.8-95.4%; 111.3-271.6%; 157.6-208.8mM Trolox Equivalent (TE), respectively. Accessions A23 (Amaranthus hypochondriacus, AHC) and A28 (Amaranthus hybridus, AHB) had higher protein and phytochemical contents than the other accessions. The activities of ALT (16.7±1.0U/L) and GGT (3.5±0.9U/L) in NaAS-treated group were significantly higher than control (ALT - 9.4±1.3U/L, GGT - 1.7±0.7U/L) and lower in groups treated with AHC plus NaAS (100mg/kg - 14.1±0.8U/L, 3.2±0.6U/L), (200mg/kg - 12.6±0.3U/L, 2.6±1.1U/L) and (300mg/kg - 9.2±0.2U/L, 1.7±0.7U/L). Activities of ALT and GGT were also lower in AHB plus NaAS treated groups (100mg/kg - 12.5±1.4U/L, 2.9±0.7U/L), (200mg/kg - 11.8±0.8U/L, 2.3±0.9U/L), and (300mg/kg - 8.6±2.7U/L, 1.8±0.6U/L) when compared with NaAS-treated group. Hepatic SOD, Catalase and GPx activities were significantly lower in NaAS-treated group when compared with control and groups administered different doses of the amaranth extracts. Amaranth accessions A23 (Amaranthus hypochondriacus) and A28 (Amaranthus hybridus) contained a good balance of essential amino acids and the ethanol extract showed dose-dependent hepatoprotective activity. The diverse clusters can be used as parents in hybridization programmes. 1 results 1
- Amaranthus 1 results 1
- Anaerobic germination 1 results 1
- Antiretroviral resistance 1 results 1
- Antiretroviral treatment 1 results 1
- Background: The use of genetically modified mosquitoes (GMMs) for the control of malaria and other mosquito-borne diseases has been proposed in malaria-endemic countries, such as Nigeria, which has the largest burden in Africa.Scientists are major stakeholders whose opinions and perceptions can adversely affect the success of the trials of GMMs if they are not involved early. Unfortunately, information on the awareness of Nigerians scientists and their overall perception of the GMMs is practically non-existent in the literature. Therefore, this study aimed at understanding how receptive Nigerian scientists are to a potential release of GMMs for the control of malaria. Methods: The sample consisted of 164 scientists selected from academic and research institutions in Nigeria. Data were collected from participants using a semi-structured, self-administered questionnaire. Questions were asked about the cause and prevention of malaria, genetic modification and biotechnology. Specific questions on perception and acceptable conditions for the potential release of GM mosquitoes in Nigeria were also covered. Results: All participants cited mosquitoes as one of several causes of malaria and used various methods for household control of mosquitoes. The main concerns expressed by the scientists were that GMMs can spread in an uncontrolled way beyond their release sites (89%) and will mate with other mosquito species to produce hybrids with unknown consequences (94.5%). Most participants (92.7%) agreed that it was important that before approving the release of GMMs in Nigeria, there had to be evidence of contingency measures available to remove the GMMs should a hazard become evident during the course of the release. In general, a majority (83.5%) of scientists who participated in this study were sceptical about a potential release in Nigeria, while 16.5% of the participants were in support. Conclusions: Although a majority of the participants are sceptical about GMMs generally, most encourage the use of genetic modification techniques to make mosquitoes incapable of spreading diseases provided that there are contingency measures to remove GMMs if a hazard becomes evident during the course of the release. 1 results 1
- Biotechnology 1 results 1
- Bornu Basin 1 results 1
- Carbonic anhydrase 1 results 1
- Cattle 1 results 1
- Cervical cancer is the fourth most common cancer in women, and the seventh of all human cancers. It is the most rampant cancer of the female genital tract in the developing world and manifests in two common histological subtypes: squamous cell carcinoma which is derived from squamous cells of the cervix and cervical adenocarcinoma which arose from the glandular cells. Most cases of deaths from cervical cancer occur in the less developed countries of the world where there are ineffective screening systems. Factors that increase the risk for developing cervical cancer include infection by Human Papilloma Virus (HPV) as the main direct factor and other indirect factors such as smoking, dietary habits, age, race, socioeconomic status, sexual history, use of oral contraceptives, high parity and the human immunodeficiency virus infection. Identifying the genetic alterations that predispose to or associate with cervical cancer will help in the screening of patients at risk of the cancer thereby allowing early diagnosis and prompt management with better outcomes. In this review we describe the role of HPV DNA integration into the host cellular genome, the effects of viral E6 and E7 proteins, and the loss of heterozygosity as genetic factors in cervical cancer. 1 results 1
- Children 1 results 1
- Clarias gariepinus 1 results 1
- Clariasgariepinus 1 results 1
- Cocoa pod husk 1 results 1
- Conservation genetics 1 results 1
- Correlation 1 results 1
- Cowpea, Vigna unguiculata, is an important human and livestock protein source in Nigeria, but its production is constrained by ravages of pests and climate change. Conventional breeding efforts used to fortify it against these constraints had resulted into its narrow genetic base. In order to overcome this challenge, other mutation procedures such as physical and chemical mutagens could be used. Nevertheless, information on gamma and ultra-violet (UV) irradiated cowpea seeds and pollen has not been adequately documented. Therefore, genetic analysis of cowpea mutants from gamma and UV irradiated seeds and pollen, respectively was investigated. Cowpea accessions seeds: IB, IB-Y1, IB-CR and IB-BPC from the University of Ibadan and IT86D-719, IT86D-1010, IT89KD-347-57 and IT90K-284-2 from International Institute of Tropical Agriculture were irradiated at 100, 200, 300, 400 and 500 Gy doses at the rate of 202 Gy/min using 60Co gamma. Pollen were irradiated for 60, 120, 180, 240, 300 and 360 minutes at 30,000µWs/cm2 UV prior to hand self-pollination using standard procedures. Radio-sensitivity of irradiated accessions were determined using seed germination (SG), seedling survival (SV), lethal dosage 50% (LD50) for SG and SV, primary leaf area (PLA) and seed set (SS) at M1 and M2 generations. The M1 of gamma irradiation (GI) and M2 of UV irradiation (UVI) treatments were advanced to M2GI and M3UV for phenotyping on field and their genetic stability confirmed at M3GI and M4UV, respectively. Genetic diversity of all mutants was determined using microsatellites. Ribulose-bisphosphate carboxylase primers were used for sequence analysis and classification of the mutants. Inheritance pattern was evaluated at M5 of gamma induced mutants (GIM) for erect-tall (ER), yellow flush (YF), four-primary leaf (FP), crinkled leaf, lettuce leaf (LL), twisted-pale leaf (TP) and burnt leaf (BL) traits. Data were analysed using descriptive statistics and Chi-square at α0.05. The M1 generation of IT90K-284-2 had 74.0% SG, while each of IB, IB-Y-1, IB-CR and IB-BPC had 20.0% SG at 500 Gy of GI. The IB, IB-Y-1, IB-CR and IB-BPC had 0.0% SV each, while 50.0% was observed in IT86D-1010 and IT90K-284-2 at 400 and 500 Gy, respectively. The LD50 for SG and SV were lowest (326 and 149 Gy, respectively) in IB-Y-1 and highest (1053 and 620 Gy, respectively) in IT90K-284-2. The PLA of M1 ranged from 2.17±0.26cm2 to 5.98±0.85cm2. Low GI (100 Gy) and UVI (60min) increased SS of M1 plants. Mutant phenotypes and frequencies varied across the cowpea accessions and did not correspond to GI treatments. Ten GIM were stable at M3, whereas all UV induced mutants reverted to normal at M4. Polymorphic information content (0.51) obtained from microsatellites showed wide genetic diversity among the mutants and parental lines. The main mutant classes were insertion-deletions and point mutations. Inheritance of ER, TP, YF, FP and BN followed monogenic recessive pattern. Genetic interaction of crinkled and TP in homozygous recessive (crl crl tp tp) conditioned LL phenotype. Radio-sensitivity of cowpea to gamma irradiation varied among the accessions. Ultra-violet radiation was less potent for cowpea pollen mutagenesis and might not be effective for mutation breeding. 1 results 1
- Cowpea, Vigna unguiculata, is an important human and livestock protein source in Nigeria, but its production is constrained by ravages of pests and climate change. Conventional breeding efforts used to fortify it against these constraints had resulted into its narrow genetic base. In order to overcome this challenge, other mutation procedures such as physical and chemical mutagens could be used. Nevertheless, information on gamma and ultra-violet (UV) irradiated cowpea seeds and pollen has not been adequately documented. Therefore, genetic analysis of cowpea mutants from gamma and UV irradiated seeds and pollen, respectively was investigated. Cowpea accessions seeds: IB, IB-Y1, IB-CR and IB-BPC from the University of Ibadan and IT86D-719, IT86D-1010, IT89KD-347-57 and IT90K-284-2 from International Institute of Tropical Agriculture were irradiated at 100, 200, 300, 400 and 500 Gy doses at the rate of 202 Gy/min using 60Co gamma. Pollen were irradiated for 60, 120, 180, 240, 300 and 360 minutes at 30,000μWs/cm2 UV prior to hand self-pollination using standard procedures. Radio-sensitivity of irradiated accessions were determined using seed germination (SG), seedling survival (SV), lethal dosage 50% (LD50) for SG and SV, primary leaf area (PLA) and seed set (SS) at M1 and M2 generations. The M1 of gamma irradiation (GI) and M2 of UV irradiation (UVI) treatments were advanced to M2GI and M3UV for phenotyping on field and their genetic stability confirmed at M3GI and M4UV, respectively. Genetic diversity of all mutants was determined using microsatellites. Ribulose-bisphosphate carboxylase primers were used for sequence analysis and classification of the mutants. Inheritance pattern was evaluated at M5 of gamma induced mutants (GIM) for erect-tall (ER), yellow flush (YF), four-primary leaf (FP), crinkled leaf, lettuce leaf (LL), twisted-pale leaf (TP) and burnt leaf (BL) traits. Data were analysed using descriptive statistics and Chi-square at α0.05. The M1 generation of IT90K-284-2 had 74.0% SG, while each of IB, IB-Y-1, IB-CR and IB-BPC had 20.0% SG at 500 Gy of GI. The IB, IB-Y-1, IB-CR and IB-BPC had UNIVERSITY OF IBADAN LIBRARY iii 0.0% SV each, while 50.0% was observed in IT86D-1010 and IT90K-284-2 at 400 and 500 Gy, respectively. The LD50 for SG and SV were lowest (326 and 149 Gy, respectively) in IB-Y-1 and highest (1053 and 620 Gy, respectively) in IT90K-284-2. The PLA of M1 ranged from 2.17±0.26cm2 to 5.98±0.85cm2. Low GI (100 Gy) and UVI (60min) increased SS of M1 plants. Mutant phenotypes and frequencies varied across the cowpea accessions and did not correspond to GI treatments. Ten GIM were stable at M3, whereas all UV induced mutants reverted to normal at M4. Polymorphic information content (0.51) obtained from microsatellites showed wide genetic diversity among the mutants and parental lines. The main mutant classes were insertion-deletions and point mutations. Inheritance of ER, TP, YF, FP and BN followed monogenic recessive pattern. Genetic interaction of crinkled and TP in homozygous recessive (crl crl tp tp) conditioned LL phenotype. Radio-sensitivity of cowpea to gamma irradiation varied among the accessions. Ultra-violet radiation was less potent for cowpea pollen mutagenesis and might not be effective for mutation breeding. Keywords: Cowpea radio-sensitivity, Gamma irradiated cowpea seed, Ultra-violet irradiated pollen, Mutant phenotypes, Pollen mutagenesis. Word count: 499 1 results 1
- Development of maize hybrids that possess tolerant genes to low soil nitrogen is critical for long-term maize production in areas with low soil fertility. In this study, estimates for combining ability effects for grain yield and secondary traits of selected inbred lines, identify potential parents for hybrid development and yield potential of the crosses under sub-optimal and optimal N environments. One hundred hybrids were evaluated under suboptimal and optimal N environments for two years. The experimental layout was a 10 X 10 alpha lattice design with two replications for two experiments. The results obtained showed that, the genotypes evaluated varied for grain yield and the characters measured under sub-optimal and optimal N conditions. Grain yield reduction due to N stress was 40.9%. General and specific combining ability (GCA) and (SCA) effects for mean squares varied for grain yield demonstrating the importance of additive and non-additive genetic effects for the hybrids evaluated under the study conditions. Even though significant variations were detected for GCA and SCA, GCA which is the additive gene action component mainly controlled the heritage of grain yield under both conditions. Inbred line 15 was identified as the superior parent with positive and significant GCA for grain yield under sub-optimal N. Genotypic correlation studies displayed that grain yield was positively correlated with ears per plant under sub-optimal N and was also positively associated with anthesis-silking interval under high N. The hybrids 52, 75, 81 and 37 were identified to be significantly superior in terms of grain yield, ASI and EPP under the two-contrasting conditions. The results suggest that, there is a need for development of low N tolerant inbred lines and hybrids for production under soils with low N status in the Guinea savanna of Ghana for high grain yield to be realised. 1 results 1
- Differentiation 1 results 1
- Direct-seeded rice 1 results 1
- see all…