DEPARTMENT OF AGRONOMY

Permanent URI for this communityhttps://repository.ui.edu.ng/handle/123456789/455

Browse

Now showing 1 - 15 of 15

CHARACTERIZATION AND EVALUATION OF SELECTED SOILS OF SOUTHERN NIGERIA FOR RUBBER (Hevea brasiliensis, Muell. Arg.) CULTIVATION
(2011-07) ORIMOLOYE, J.R.
Successful land management for tree crop production requires good knowledge of the soil variation and suitability for specific tree crops. Most of the traditional rubber growing areas in Nigeria have not been evaluated for their suitability and production potential. Characterisation and evaluation of the land for rubber production was therefore conducted. Soils of two rubber producing areas: Iyanomo, Edo State and Akwete, Abia State were characterised and evaluated using local, United States Department of Agriculture (USDA Soil Taxonomy) and FAO systems. Conventional parametric and non-parametric land suitability evaluation systems as well as Geographic Information System (GIS) methods were used to generate suitability ratings for rubber cultivation. Dry rubber yield from existing plantations on the two sites obtained in the 2005/2006 and 2006/2007 cropping seasons were used to validate the suitability ratings. Effects of soil and weather parameters on rubber yield were determined. Influence of the three stages of development of rubber plantations on soil properties were compared with forest and arable land use types. Data were analysed using descriptive statistics, correlation, concordance, path analysis and ANOVA at p = 0.05. The soils studied were classified as Alagba, Orlu, Kulfo and Ahiara series at Iyanomo and Uyo, Calabar and Etinan Series at Akwete. The soils were in the Ultisol and Inceptisol soil orders of the Soil Taxonomy. The Ultisols covered 73.1 % and 70.9 % of the study area at Iyanomo and Akwete respectively; while Inceptisol covered 26.9 % and 29.1 % at Iyanomo and Akwete respectively. Soil maps produced by GIS and conventional method were not significantly different. Parametric and non-parametric land suitability evaluation rated 73.1 % and 26.9 % of studied area at Iyanomo as moderately suitable (S2) and marginally suitable (S3) respectively but 70.9 % and 29.1 % of Akwete site as S3 and not suitable (NS) respectively. The GIS method however rated 88.0 % of the Iyanomo site as highly suitable (S1) and 12.0 % as S2 and 52.8 % and 47.2 % of Akwete site as S1 and S2 respectively. Correlation between soil classes and actual rubber yield were not significant in 2005/2006 and 2006/2007 cropping seasons but soil classes significantly correlated with yield index in 2006/2007 season for both sites. Observed yield index ranged between 79.9 – 124.0 in 2005/2006 and 71.4 – 195.1 in 2006/2007 and were higher than the expected indices from conventional evaluation systems. Correlation coefficients of rainfall (r = 0.340*), humidity (r = - 0.245**), and path analyses revealed that relative humidity, K, bulk density and porosity were factors that significantly affect rubber yield. Majority of the soils were Ultisols and Inceptisols and were suitable for rubber production. Suitability evaluation with Geographic Information System is better than conventional methods in predicting yield of rubber.
EFFECTS OF INTEGRATED USE OF VETIVER GRASS STRIPS AND MULCH ON SOIL EROSION AND MAIZE GRAIN YIELD IN IKENNE, NIGERIA
(2016-07) ARE, KAYODE
Soil erosion is a major threat to sustainable agriculture in the humid tropics. Management practices adopted to control soil erosion and improve soil quality include mulching and the use of Vetiver Grass Strips (VGS). Integrating VGS with mulch could be more effective in controlling soil erosion than VGS or mulching alone. However, information on the effectiveness of combined utilisation of VGS and Vetiver Mulch (VM) in controlling soil erosion and improving crop yield is scanty. Therefore, this study was carried out to quantify the effects of integrating VGS and VM on soil erosion, soil quality and maize Grain Yield (GY). Three soil erosion control experiments were conducted on a Rhodic Kandiudult soil with 7% slope, in Ikenne, using maize as test crop. Treatments in each experiment were laid out in a randomised complete block design with three replications. The potential of VGS spaced at 10 m intervals (10VGS) and 6 t/ha of VM (VM6) in reducing runoff, soil and nutrient losses was evaluated. Treatment with No Vetiver grass (NV) served as control. Runoff and soil loss were measured. Carbon, nitrogen and phosphorus contents of eroded sediment were determined using standard methods. In another experiment, 10VGS and VGS spaced at 20 m intervals (20VGS) were integrated with VM of 2 (VM2) and 4 (VM4) t/ha as: 10VGS+VM2, 10VGS+VM4, 20VGS+VM2 and 20VGS+VM4. The four integrated treatments and 10VGS, 20VGS, VM2, VM4, VM6 and NV were evaluated for their effectiveness in reducing erosion. Data were collected on soil loss and maize GY. Soil Physical Quality Index (SPQI) was estimated using the soil management assessment framework. Also, 10VGS+VM4, 10VGS, VM6 and NV were assessed for their effectiveness in reducing nitrate-N and phosphate-P in runoff. The nitrate-N and phosphate-P concentrations were determined using standard methods, and Eutrophic Quality Index (EQI) estimated. Data were analysed using descriptive statistics and ANOVA at α0.05. Runoff from 10VGS, VM6 and NV were 20.5±5.4, 16.9±6.7 and 30.9±2.3 mm while soil losses were 337.5±9.9, 402.5±40.0 and 1079.0±18.3 kg/ha, respectively. Carbon, nitrogen and phosphorus contents of eroded sediments for VM6 (12.65 g/kg, 1.25 g/kg and 7.60 mg/kg) and NV (16.90 g/kg, 1.70 g/kg and 8.30 mg/kg) were higher than for 10VGS (11.05 g/kg, 1.15 g/kg and 7.30 mg/kg). Soil loss was lowest under 10VGS+VM4 (1.48±0.06 t/ha/yr) and highest under NV (7.49±0.94 t/ha/yr). Soil loss increased in the order of 10VGS+VM4 <10VGS+VM2 <10VGS
EFFECTS OF POSTHARVEST HANDLING METHODS AND STORAGE CONDITIONS ON STORABILITY OF PEPPER (Capsicum frutescens L.) FRUITS IN SOUTHWEST NIGERIA
(2014-08) ADEWOYIN, OLUYINKA BENEDICTA,
Pepper a perishable seasonal fruit, requires storage to extend its shelf-life. Appropriate postharvest handling and storage prolong longevity and preserve quality of Pepper Fruit (PF). However, there is dearth of information on its handling and storage in Southwest Nigeria. Therefore, the effects of postharvest handling methods and storage conditions on storability of PF were investigated. Two hundred Pepper Fruit Marketers (PFM) were randomly selected from pepper markets in Ibadan, Oyo State (Sasa and Bodija), Iwo, Osun state (Erunmu, Odo-Ori, and Station) and Akure, Ondo State (viz: Isikan, Oja-Oba, Sasa, NEPA and Isolo). Structured questionnaire was used to determine the socioeconomic characteristics of PFM and postharvest handling methods. Capsicum frutescens grown on the Teaching and Research Farm, University of Ibadan was harvested with and without pedicels at 10 and 100% ripeness. Postharvest handling was evaluated by comparing packaging in perforated polyethylene, non-perforated polyethylene and aluminium-foil before storing in either Ambient Conditions (AC) of 21.9-33.5°C and 58-62% Relative Humidity (RH); Refrigerator (4.0°C and 40-45% RH) or Evaporative Coolant Structure (ECS) (18 - 20°C and 70-75% RH). Pepper fruits were heat-sterilised, parboiled and unparboiled before oven-drying or sun-drying in order to determine the effect of processing on proximate and Vitamin C Content (VCC). Percentage Weight Loss (WL) was calculated. Firmness (FM) and Decay Level (DL) were evaluated on a scale of 1 to 4 and General Appearance (GA) on scale of 1 to 5. Data were analysed using descriptive statistics, correlation coefficient and ANOVA at p < 0.05. The average age of PF marketers was 45 years with male predominance (56%). Majority (69.0%) spread PF on cemented floor to minimise deterioration; Sixty-six percent removed spoilt fruits to reduce infection. Seventy-four percent sourced PF from middlemen these were inappropriately transported in commuter vehicles with used grain sack. Fruits were marketed at 100% ripeness without pedicels. Evidence of deterioration due to presence of insect larvae and rottenness was observed from the 5th day after storage. The shelf-life of PF harvested with pedicels at 10% ripeness and stored in refrigerator, ECS and AC was 27, 20 and 6 days, respectively, while shelf life of PF harvested at 100% ripeness was 21, 14, and 3 days, UNIVERSITY OF IBADAN LIBRARY iii respectively. In contrast, the shelf-life of PF harvested without pedicel at 10% ripeness was 21, 18 and 5 days while for 100% ripeness, it was 18, 15 and 2 days respectively. The WL, DL, GA and firmness of fruits harvested at 10% with pedicels and stored in refrigerator was 14.3%, 3.2, 4.0 and 3.5. The PF packaged in the aluminium-foil had significantly longer shelf life (30 days) than those packaged in perforated polyethylene (21 days) and non-perforated polyethylene (15 days). Parboiled-sundried pepper was significantly higher in crude protein (15.2%), fat (11.3 %), capsaicin (27.8%), and VCC (9.6 mg/100 g) compared to oven-dried pepper. Heat-sterilised fruits had the lowest nutrient contents. Storability of PF was best at 10% ripeness with pedicel. Parboiled-sundried method conserved nutrients better than other techniques. Keywords: Pepper storability, Postharvest handling, Capsicum frutescens. Word count: 487
Effects of pre-storage treatments on sprouting and nutritional quality of ginger (zingiberofficinalerosc) rhizomes in different storage periods
(International Peer Reviewed Journal and book Publishing, 2016) Olaniyi, J. O.; Olusoga, S.; Babatola, L. A.; Atanda, T. T.
Purpose: Ginger rhizomes are highly susceptible to damage during postharvest storage due to soil borne pathogenic disorder. Experiments were conducted to evaluate the effects of prestorage treatments required for sprouting and maintaining the quality of ginger plant in different storage periods at the Teaching and Research Farm, Ladoke Akintola University of Technology, Ogbomoso. Method: The rhizomes were treated with four different pre-storage treatments viz.,control, hydrated lime, - Mancozeb, and 100ml of Trichodermaharzianum solution at different storage periods of one, two and three months. The experiment was arranged in a complete randomized designand laid out in a randomized complete block design with three replicates. Data were collected on percentage sprouting, plant height, number of leaves, leaf area and nutritional quality of ginger rhizomes. Data were subjected to analysis of variance using Statistical Analysis System Software (SAS, 2005). Differences among treatment means were compared using Least Significance Difference (LSD) at 5% probability level. Results: The storage periods significantly (P≤0.05) influenced the percentage sprouting andgrowth parametersof ginger at various sampling period. Highest growth of 9.05cm was recorded from ginger plant stored for three months while the least value of 6.94cm was obtained from rhizomes stored for one month. The pre-storage treatments significantly (P≤0.05) influenced the percentage sprouting, weight loss and growth parameters of ginger at various sampling period. Highest percentage sprouting (94.3%) was recorded from rhizomes treated with 100 ml Trichodermaharzianim solution followed by rhizomes treated with hydrated lime (88.3 %) while lowest percentage sprouting (61.5 %) were recorded from control. Highest percentage weight loss of 46.3% was recorded from control followed by hydrated lime (35.58 %) while the lowest percentage weight loss of 33.93 % was recorded from 100 ml Trichodermaharzianim solution. Conclusions: In conclusion, rhizomes treated with Trichodermaharzianim solution for a period of three months before planting produced better sprouting and enhanced the growth quality of ginger on the field
EFFECTS OF SOME FIELD PRACTICES ON THE YIELD AND QUALITY OF CASSAVA (Manihot esculenta Crantz) PLANTING MATERIAL
(2011) Yomeni, M. O.
The use of cassava stems as planting materials is limited by scarcity, poor quality, high cost and inappropriate field techniques (land preparation, planting spacing, and field maintenance). To enhance the supply of stem for planting cassava varieties, the existing production practices were evaluated and techniques for increasing the number and quality of cassava planting materials were investigated.Seventy-four cassava farms, purposively selected in 11 major cassava growing
EVALUATION OF MEHLICH - 3 AS A MULTIPURPOSE EXTRACTANT OF PHOSPHORUS AND POTASSIUM USING BELL PEPPER (Capsicum annuum L.) IN SOME NIGERIAN SOILS
(2016-09) OLUWAYOMBO, OLAWALE OLUFUNMI
Use of single soil specific extractants to determine plant available phosphorus and exchangeable potassium for crops such as bell pepper, are costly, laborious and time wasting. Bell pepper, rich in antioxidants, requires phosphorus and potassium for high quality fruit yield. Mehlich-3 (M3), a multi-purpose extractant could extract phosphorus and potassium simultaneously. However, M3 has not been evaluated and adapted for Nigerian soils. Therefore, M3 as a multi-purpose extractant of P and K from soil for bell pepper was evaluated. Phosphorus and potassium extractions were carried out on soil (0–15 cm) samples from 12 purposively selected sites belonging to eight soil series across three agro-ecological zones (derived savanna, humid forest and northern guinea savanna) of Nigeria. Bray 1 (B1), Bray 2 (B2) and Olsen were used to extract phosphorus; 1M Ammonium acetate pH 7.0 (AAc) was used to extract potassium, while M3, Ammonium hydrogen flouride+DTPA (ABD) and modified M3 (MM3) were used to extract phosphorus and potassium simultaneously. Concentrations of phosphorus and potassium extracted by different extractants were determined using standard procedures. In the screenhouse, pots were filled with 3 kg each of the 12 soil samples and laid in a completely randomised design (n=108). Bell pepper was grown at one plant per pot for four weeks. Phosphorus and potassium uptakes were determined. Field experiment was conducted on Egbeda, Apomu and Jago soil series for three cropping seasons to determine critical range of soil phosphorus and potassium and optimum fertiliser rates using M3. Phosphorus (0, 30, 45 and 60 kg/ha) and potassium (0, 15, 30 and 45 kg/ha) were applied in a split plot arrangement in a randomised complete block design, replicated thrice. Fruit yield of bell pepper was measured. Data were analysed using descriptive statistics, correlation and quadratic regression at α0.05. Phosphorus extracted by B1, B2, Olsen, ABD, MM3 and M3 were 8.34±1.22, 11.19±2.62, 5.11±1.68, 30.33±4.32, 15.68±3.48 and 14.41±4.32 mg/kg, respectively, while potassium extracted by AAc, ABD, MM3 and M3 were 0.47±0.02, 0.21±0.02, 0.36±0.05 and 0.59±0.09 cmol/kg, respectively. Phosphorus and potassium uptakes were 2.34±0.5 and 22.62±2.28 g/kg, respectively. Significant correlations exist between extracted phosphorus and potassium with their uptakes, except ABD for potassium. Correlations of phosphorus and potassium extracted by M3 with their uptakes were the highest (r=0.95), while the lowest was in B1 (0.78) for phosphorus UNIVERSITY OF IBADAN LIBRARY iii and MM3 (0.93) for potassium. The yields (t/ha) of bell pepper across seasons were 15.02±0.51 (Egbeda), 14.19±0.36 (Apomu) and 5.15±0.40 (Jago). Fruit yield was significantly influenced by applied fertilisers with phosphorus lowest in Apomu (r2=0.65) and highest in Jago (r2=0.99), for potassium, the least was in Jago (r2=0.52) and highest in Egbeda (r2=0.99). Critical ranges of phosphorus and potassium in the soils were 15 (Apomu) to 20 (Jago) mg/kg and 0.20 (Apomu) to 0.25 (Jago) cmol/kg, respectively. Optimum phosphorus and potassium concentrations for bell pepper were 45 kg/ha and 30 kg/ha, respectively. Mehlich-3 is a good simultaneous extractant of phosphorus and potassium across the agro-ecological zones. It is therefore recommended for evaluating soil phosphorus and potassium. Keywords: Multipurpose soil extractants; Mehlich-3 extractant; Phosphorus uptake; Bell pepper yield; Word count: 494
GENETIC VARIABILITY FOR STEM BORER RESISTANCE IN TWO ADAPTED EARLY-MATURING MAIZE (Zea mays L.) POPULATIONS
(2013-03) OLOYEDE-KAMIYO, Q. O.
Stem borers are among the major biotic stresses limiting the grain yield of maize, an important cereal crop in Africa. Breeding for multiple resistance to maize stem borers has been reported to be a promising method of control. Understanding the genetic variability of crop populations will help in improving them for pest resistance. Thus, genetic variability for dual resistance to two stem borer species were determined in a white (DMR ESR-W) and a yellow (DMR ESR-Y) maize populations to provide information required for improving their levels of resistance to the borers. Two experiments were conducted. In Experiment 1, a set of 100 S1 plants of DMR ESR-W were selected to produce 250 full-sib and half-sib progenies using the North Carolina Design II (NCD II) mating scheme. The progenies with six checks were evaluated under artificial infestation with two borer species (Sesamia calamistis and (Eldana saccharina) at Ibadan, and non-infested conditions at Ibadan and Ikenne in 2008 and 2009 using Randomized Incomplete Block Design with two replications. Experiment 2 was with DMR ESR-Y and the same methodology was used. In both experiments, days to 50% anthesis and silking, plant and ear height, plant and ear aspect, ear length and grain yield were measured. Resistance was measured according to levels of leaf feeding damage, dead heart, stalk breakage, cob damage and stem tunneling. Analyses of variance for NCD II were conducted to estimate genetic variances and Narrow-Sense Heritability (NSH). Correlation coefficients were determined and partitioned into direct and indirect effects. Predicted responses to selection were estimated to measure expected genetic gains. Correlated response was used to determine traits that could hasten selection progress. Tests of significance were conducted at p < 0.05. Infestation significantly reduced plant height (6.0 -11.1%), ear length (20.9 - 25.6%) and grain yield (23.9 - 30.4%) in both maize populations. Additive variance was significant for grain yield and stalk breakage in DMR ESR-W, and for stalk breakage, cob damage and stem tunneling in DMR ESR-Y. Narrow-sense heritability was low to moderate, but low for damage parameters except stalk breakage (40.6%) in DMR ESR-W, and cob damage (40.1%) in DMR ESR-Y. Negative correlations exist between grain yield and increasing levels of stem borer damage, with genotypic correlation between grain yield and stem tunneling being the highest (-0.52*) in DMR ESR-Y. Stem tunneling and cob damage had high positive direct effects on grain yield reduction. Estimated genetic gain per generation was 4.0 - 6.1% (= 210kg/ha) for grain yield under infestation in DMR ESR-W, but low for damage parameters in both maize populations. Direct selection for individual trait gave better response than indirect selection through other traits. The significant additive variances and moderate heritability estimates obtained for stalk breakage and cob damage indicate that the traits are heritable, therefore, improvement of the maize populations for stem borer resistance using these traits is feasible. Direct selection for grain yield is recommended in improving the maize populations. Stem tunneling and cob damage by the borers are major causes of grain yield reduction.
INFLUENCE OF STARTER NITROGEN APPLICATION ON YIELDS OF TWO SOYA BEAN VARIETIES GROWN ON FERRIC LUVISOL IN OYO STATE, NIGERIA
(2016) Oyatokun, O. S.
Nitrogen is a major soil nutrient for the growth and development of crops. Nitrogen deficiency in-between pre-nodulation and nodulation in soya bean is critical to enhancing its growth and yield. Decision Support Systems for Agro-technology Transfer (DSSAT) model like CROPGRO-soya bean could be a useful tool for predicting starter nitrogen requirement in soya bean. However, information on starter nitrogen application to overcome N-deficiency-induced-stress during early seedling growth and prediction using CROPGRO-soya bean is limited. This study was undertaken to investigate the effect of starter nitrogen on soya bean yield grown on ferric luvisol in Oyo State, Nigeria.Field experiment involving two soya bean varieties (TGx1485-1D and TGx1448-2E) and five starter nitrogen rates (0, 5, 15, 25 and 35 kg/ha) was carried out for two seasons at Ipapo and Gbonran in Itesiwaju Local Government Area of Oyo State. The experiment was laid out as split-plot in a randomised complete block design with three replications. Nitrogen rate and soya bean variety were main and sub-plot factors, respectively. Shoot Dry Weight (SDW, t/ha), Grain Yield (GY, t/ha), Harvest Index (HI) and Shoot Nitrogen Content (SNC, g/kg) were measured. In screenhouse, soil from each location was filled into pots (5 kg) and each variety was planted under optimum management practices in a completely randomised design with three replications. Data on days to seedling emergence, days to first pod appearance and days to physiological maturity were obtained, fitted and used to calibrate CROPGRO-soya bean model. Data on weather parameters, soil description and characterisation (pH, field capacity, permanent wilting point, bulk density and hydraulic conductivity) were used for predicting phenology and yield. Data were analysed using ANOVA at α0.05, and model outputs were evaluated with percentage error (PE).Nitrogen rate had no significant effect on SDW, while variety TGx1448-2E had significantly higher SDW (2.9±0.3) and GY (1.5±0.1) than TGx1485-1D (2.3±0.3 and 1.3±0.1, respectively) at both locations. Nitrogen rate had no significant effects on GY and HI at Gbonran. However, 15 kgN/ha produced a significantly highest GY (1.4±0.1) than the control (1.2±0.1), while HI at 5 kgN/ha (0.60±0.02) was highest at Ipapo. Variety TGx1485-1D had significantly higher HI (0.58±0.05) than TGx1448-2E (0.52±0.05) at both locations. Nitrogen rate had no significant effect on SNC at both locations. Variety TGx1485-1D had significantly higher SNC (33.0±1.5) than TGx1448-2E (26.0±1.5) at Ipapo. CROPGRO-Soya bean model predicted soya bean phenology across nitrogen rates within 0 – 1 day of the observed values at both locations. Predicted yield of TGx1485-1D was 1.5 t/ha across N rates with PE < 15%, while that of TGx1448-2E was 2.6 t/ha with PE > 30%. Application of starter nitrogen had no effect on yields of soya bean at Gbonran but 15 kgN/ha enhanced grain yield of soya bean at Ipapo. Variety TGx1448-2E had better biomass yield, while TGx1485-1D had better nitrogen content on ferric luvisol. Prediction of CROPGRO-soya bean model was reliable for phenology and yield of TGx1485-1D but not reliable for yield of TGx1448-2E
Nitrogen-Use Efficiency and Gene Expression Profiling of Tropical Maize Hybrids Selected for Contrasting Responses to Nitrogen Fertilizer
(2012) Abe, A.
Low soil Nitrogen (N) and sub-optimal N fertilizer application result in low Grain Yield (GY) in maize. Genotypes with improved N-Use Efficiency (NUE) are beneficial to low-input agriculture. To facilitate the genetic improvement of tropical maize for NUE, information is required on the relative importance of N-Uptake Efficiency (NUpE) and N-Utilization Efficiency (NUtE), both components of NUE, the relationships among the gene networks in the developing cob tissue and agronomic traits under limited N. This study was undertaken to evaluate genetic variation for NUE and investigate gene responses in the developing maize cob under sub-optimal N fertilizer application. Fourteen tropical maize hybrids differing in GY under low-N conditions were grown at no-N (0 kg N/ha), low-N (30 kg N/ha), and high-N (90 kg N/ha) in a randomized complete block design with four replications from 2006 to 2008. Data collected on GY and its components, NUE, NUpE, NUtE, and N-related traits were analysed using ANOVA at p=0.05. Path analysis was carried out to capture the intricate relationships among traits related to GY and NUE. Microarray technique using Maize Oligonucleotide array slides containing ~57000 probes were used to identify differentially expressed genes in developing cob tissues harvested from three N-use efficient hybrids compared to an N-use inefficient reference hybrid. Differentially expressed genes were validated by quantitative Real Time Polymerase Chain Reaction (qRT-PCR). Genotype and Genotype × Nitrogen interaction were significant for GY and NUE-related traits. Mean GY across years was reduced by 76.5% at no-N and 35.4% at low-N. It varied from 2.0 to 3.2 Mg/ha at low-N and 3.3 to 4.4 Mg/ha at high-N. Number of kernels (KN) was the GY component most severely reduced under nitrogen stress. Nitrogen use efficiency, NUtE and NUpE increased by 61.4, 42.1 and 21.0% respectively from high-N to low-N. Grain yield was positively and significantly correlated with NUE, NUtE and NUpE at both low-N and high-N. Stover nitrogen content at silking and NUE had strong positive direct effects on GY under low-N and high-N. Both NUtE and NUpE had significant positive direct effects on NUE. The relative importance of NUpE and NUtE varied depending on genotype and environment. Four hybrids (4001/4008, KU1409/9613, KU1409/4008 and 4008/1808) produced similar above average GY at low-N and high-N but differed in their NUpE and NUtE. Gene expression profiling of developing cob tissues revealed that at low-N, 163 of the probes on the array showed differential expression across the test hybrids. Under low-N, the probe MZ00019244 corresponding to the L-asparaginase gene showed the strongest relative mRNA expression in the highest yielding hybrid (KU1409/9613). L-asparaginase mRNA expression level was positively and significantly correlated with GY, KN and NUtE. Genetic variation for nitrogen use efficiency and its components was present among the tropical hybrids. L-asparaginase mRNA expression would be a valuable tool for selecting maize genotypes with high nitrogen utilization efficiency and superior grain yield under low soil nitrogen
Poverty and land access in Igbo land Nigeria: implications for policy and Agroenterpreneurship development
(2013-12) Azeez, I. O; Onyema, M.C
Household livelihood across Africa 50 years after independence have recorded lean improvements especially in terms of access to essential production inputs. Household rate of land access, means of access, Household rate of land access, means of access, welfare and investment capacities, land cost and the linkage between access to land and the above measured parameters were investigated using a set of questionnaires administered to urban and rural settlements. Descriptive results showed that poverty incidence was high (60%) especially in rural areas is distant from expectations of the MDGs. Lands were obtained majorly through land purchase indicative of growing land commercialization whose cost (per ha.) ranged from N500,000 to N1m. Access to land (in rural, urban settlements) had low positive correlations with age in both settlements (0.181, 0.163), with education (0.183, 0.25) and welfare capacity (0.25, 0.82). Similarly, regression line showed negative slopes, low but positive coefficients (R2) with welfare poverty (R2=0.041) and investment poverty (R2=0.017) indicating limiting influence of different poverty forms to livelihood and household productivity. Periodic review of land administration, unified land policy thrust along the lines of reviving interest especially among youths in agriculture through incentives (tuition-free agricultural disciplines), implementation synergy, capacity building and granting of loans as financial safety net are key achievable policy options.
RESPONSE OF KENAF (Hibiscus cannabinus Linn.) TO FERTILIZERS AND ARBUSCULAR MYCORRHIZA IN A NUTRIENT DEGRADED ALFISOL IN IBADAN, SOUTHWESTERN NIGERIA
(2011) Bada, B. S.
High and sustainable kenaf production in a fragile tropical soil requires the use of soil amendments. Arbuscular Mycorrhizae (AM) are important for nutrition of plants in nutrient depleted soils of the tropics. Due to insufficient information on kenaf production using fertilizers and AM, the effects of fertilizers and AM on soil chemical properties, growth and fibre yield of kenaf were investigated. Screenhouse and field experiments were conducted at the Institute of Agricultural Research and Training, Ibadan. The AM colonization of kenaf was assessed in the screenhouse experiment consisting of 2 x 12 x 2 factorial in a Randomized Complete Block Design (RCBD) with three replicates. The treatments were with mycorrhiza (M+) and without (M-), twelve levels of fertilizers: 0, NPK 20:10:10 (60 kgN/ha), organic (20, 40, 60, 80 and 100 kgN/ha), and organo-mineral (20, 40, 60, 80 and 100 kgN/ha) and two kenaf varieties (Cuba 108 and Tiannug 1). The higher yielding variety (Cuba 108) was used on the field to determine the optimum fertilizer rate for fibre production. The experimental design was split-plot in RCBD. Mycorrhizal inoculation was the main plot and twelve fertilizer levels as the sub-plot with three replicates. Residual effect of the treatments was also determined. Data on soil chemical properties, AM Root Colonization (RC), growth and yield parameters were collected and analysed using descriptive statistics and ANOVA. Screenhouse and field experimental soils were low in organic matter with 15.0 g/kg and 13.0 g/kg, respectively. Under screenhouse, AM colonization ranged from 14.4 to 78.1 % in the two varieties of kenaf. Inoculated Cuba 108 at 40 kgN/ha Organo-Mineral Fertilizer (OMF) had significantly (p<0.05) higher stem girth (1.8 cm), plant height (275.2 cm), RC (79.8 %), bast (9.6 g/pot) and core (19.9 g/pot) yields than other treatments. On the field, optimum bast and core yields of 3.8 and 9.4 t/ha respectively were obtained at M+ 40 kgN/ha OMF. Comparing 60 kgN/ha of fertilizers, M + OMF had significantly (p<0.05) highest bast and core yields followed by M+ NPK and M- OMF while M- Organic Fertilizer (OF) had the least. After harvesting, M- 100 kgN/ha OF had the highest organic matter, 25.9 g/kg; total N, 0.8 g/kg; available P, 6.8 mg/kg; exchangeable K, 0.4 cmol/kg and Ca, 9.6 cmol/kg. For the residual effect, M+ 100 kgN/ha OF had significantly (p<0.05) highest RC (69.0%), bast (2.7 t/ha) and core (5.8 t/ha) yields. Considering the 60 kgN/ha of fertilizers, organic had the highest bast and core yields followed by organo-mineral and inorganic. The highest organic matter was observed in M- 100 kgN/ha OF. Cuba 108 and Tiannug 1 roots were highly colonized by arbuscular mycorrhiza, while the optimum bast and core yields were observed in the inoculated Cuba 108 at 40 kgN/ha of organo-mineral fertilizer. Management of organo-mineral fertilizer along with indigenous mycorrhizae will reduce the application of chemical fertilizers and ensure optimum quantitative yield of kenaf under the assayed soil conditions
RESPONSE OF YAM (Dioscorea spp.) ACCESSIONS TO DROUGHT AND ARBUSCULAR MYCORRHIZAL FUNGI
(2016) Odoh, N. C.
Moisture deficit limits yam production. Availability of drought tolerant yam will improve yield and expand area of production. Soil inoculation with Arbuscular Mycorrhizae Fungi (AMF) improves tolerance of plants to drought. However, there is limited information on the response of yam to drought and AMF inoculum. This study was conducted to identify drought tolerant yam accessions and determine the effects of AMF.Two glasshouse and one field experiments were conducted, each in a randomized complete block design with three blocks. In the first glasshouse experiment, 32 accessions of Dioscorea alata and 49 of D. rotundata obtained from the International Institute of Tropical Agriculture, Ibadan were screened for drought tolerance. Pre-sprouted setts were planted in pots containing 5 kg soil, watered to Field Capacity (FC), wrapped with transparent polyethylene sheets and observed for 90 days. Twelve accessions of each species selected on the basis of their superior performance were further evaluated at three moisture levels: 75% FC at 11 Weeks After Planting (WAP) 25% FC at 15 WAP and 25% FC at 11 WAP,with and without AMF inoculation. Three promising drought tolerant accessions of each species were selected from the second experiment and evaluated in the field. Treatments were two irrigation intervals with 12 mm water (four-day and monthly), three planting dates (monthly: July, August, September) and AMF inoculations (with and without) laid out as split-split-split plot. Data were collected on Fresh and Dry Tuber Weight (FTW and DTW), Harvest Index (HI), mycorrhizal colonisation and number of AMF spores. Data were analysed using descriptive statistics, correlation and ANOVA at α 0.05.The accessions differed significantly in their response to water- and AMF- levels for most growth and yield parameters. The FTW per plant ranged from 24.0±7.7 g (TDa02/00012) to 54.0±10.0 g (TDa297) in D. alata and 13.0±1.8 g (TDr99/02789) to 57.0±9.2 g (TDrAbi) in D. rotundata. Drought stress at 25% FC, 11 WAP resulted in 83% reduction in FTW as compared to a decline of 67.8% at 25% FC, 15 WAP in D. alata. Mycorrhizal inoculation significantly increased the FTW by 58% and DTW by 112% for D. alata while increases of 33% and 38%, respectively were recorded for D. rotundata. The FTW (D. alata and D. rotundata) was significantly correlated with DTW (r= 0.89, 0.91), HI (r= 0.80, 0.78), number of AMF spores (r= 0.53, 0.55) and mycorrhizal colonisation (r= 0.32, 0.30) respectively. In the field, irrigation at four-day intervals improved tuber yield of D. rotundata by 50% relative to monthly irrigation. The highest FTW (10±0.7 t/ha) for D. alata was obtained with the July planting while the September planting had the least (3±0.7 t/ha). Across treatments, accessions TDa02/00012 of D. alata and TDrSaminaka of D. rotundata had the highest FTW of 7.0±1.0 t/ha and 5.0±1.0 t/ha, respectively.Variation for drought tolerance exists among D. alata and D. rotundata accessions studied. Mycorrhizal inoculation improved yam yield under moisture stress. Accessions TDa02/00012, TDa93-36, TDaKesofunfun of D. alata and TDrSaminaka, TDrAloshi, TDrAbi of D. rotundata were most drought tolerant
SEED PRODUCTION IN OKRA (ABELMOSCHUS ESCULENTUS (L.) MOENCH)
(1987-08) ADETUNJI, I. A.
Fifteen genotypes of okra were evaluated in eight environments for stability of seed yield, and also to identify the most suitable environments for producing high quality seed at the University of Ibadan, Nigeria from 1984 to 1986. There was significant genotype x environment interactions for all characters examined except for percent seed germination. On the average, highest seed yield and best seed quality as measured by percent seed germination were associated with environments with low total precipitation (460.4 mm), low average relative humidity (50.1%) and high number of sunshine hours (1153.7 hrs). Studies on agronomic requirements for okra seed production revealed that high plant population (111,110 plants/ha) produced about 39% higher seed yields/ha than low plant population of 55,555 plants/ha. Nitrogen levels of 65 kg/ha and 130 kg/ha raised seed yield by 35 and 39% over the control (no nitrogen) respectively. Seeds harvested 35-49 DAF, stored in polythene bags at 4°C with 50% RH retained most of their viability after 16 months of storage. Removing the first two to four edible pods on each plant raised okra seed yields by about three percent. Removal of the first 6 to 14 pods/plant reduced seed yields by 36-80%. Removal of up to four edible pods/ plant was compensated for by higher total pod dry matter yield reflected in a higher 1000-seed weight and larger size of seeds. Seeds in categories of 4.0 and 4.5 mm size grades were more vigorous as indicated by 1000-seed weight, percent seed germination and seedling emergence.
USE OF COVER CROPS AND PRE-EMERGENCE HERBICIDES AS WEED MANAGEMENT OPTION IN CONTINUOUS MAIZE (Zea mays L.) PRODUCTION IN IBADAN, NIGERIA
(2013) Olaniyi, O. W.
Crop Rotation (CR) and planting of Cover Crops (CC) are important methods of weed management for sustainable crop production.These and various other methods are usually integrated to enhance weed management in crop production. While reports abound on integrated weed management involving these and other practices, there is inadequate information on integrated use of Pre-emergence Herbicides (PH), CC, and CR in maize production. Therefore, effects of continuous use of CC with PH were evaluated in Ibadan for maize production. Hundred, 75, 50 and 25% of the recommended rates of maize-based PH (atrazine, atrazine+ metolaclor® and metolaclor®) were evaluated on the performance of Cowpea (α), Melon (β), Pumpkin (γ) and “Akidi” (Vigna unguiculata sub-sp sesquipedalis) (θ).The densities of 10,000 and 20,000 plants/ha for γ and α/β/θ respectively were integrated with the effective minimum dose of the PH and evaluated on weed control and maize performance. The appropriate sequence of the CC complemented with hoe-weeding at four Weeks After Sowing (WAS) for weed suppression in intensive maize cropping over four cropping cycles in two years was also evaluated in randomized complete block design. The CC sequences were combinations of any of γ/βand θ/α in early and late seasons (βθγα/βαγθ/γθβα/γαβθ) and continuous sole CC (ββββ/θθθθ/γγγγ/αααα) over four cropping cycles. The controls in each case were three hoe-weedings and unweeded maize plots. Data collected on emergence and Dry Matter Yields (DMY) of the CC, Ground Coverage (GC) of CC,Weed Density (WD), weed biomass at 8 WAS and Maize Grain Yield (MGY) were analysed using descriptive statistics and ANOVA at p=0.05.
USE OF REMOTE SENSING TECHNIQUE IN THE LANDUSE/LANDCOVER EVALUATION OF DRY RAIN FOREST OF SOUTHWESTERN NIGERIA
(2012-08) EDOSOMWAN, LAWRENCE NOSA
The dearth of up-to-date information on the Nigerian natural resources is a major hindrance to their optimal and sustainable use for national development. Remote sensing technique enables faster and more accurate acquisition of information than that of conventional approach to natural resources survey. However, their uses are yet to be fully exploited. This study was therefore designed to produce LandUse/LandCover (LULC) maps of Southwestern Nigeria using remote sensing technique and also evaluate soils of the same area for crop production. Multidate maps (1975, 1986 and 2002 of LULC covering 23,629.2 ha for Ife and 13,653 ha for Ilesha areas were derived from aerial photographs of 1975 using mirror stereoscopes and Landsat thematic mapper data for 1986 and 2002. The changes in the LULC were evaluated for built-up, hill/water, fallow/cropland and forest areas. Semi-detailed soil maps of the two areas were produced using aerial photographs and Systeme Probatoire Pour Observation de la Terre (SPOT) Imagery to evaluate the degree of concordance between them. The soil series identified using FAO guidelines were evaluated for potential crop suitability using Land Evaluation Computer (LEC) system. Data were analyzed using descriptive statistics. In LULC of Ife area, there was a general increase of 4.2% (1975 – 1986) and 5.6% (1986 – 2002) in built-up areas; 1.4% (1975 – 1986) and 4.2% (1986 – 2002) in the fallow/crop areas; 0.88% (1975 – 1986) and 3.7% (1986 – 2002) in Hill/Water areas; and a decrease of 3.7% (1975 – 1986) and 5.0% (1986 – 2002) in the forest areas. Concordance between the two soil maps of the area was 32.0%. Thirteen soil series were identified out of which four (Araromi, Itagunmodi, Owena and Egbeda) series were moderately suitable (S2) for maize; seven were moderately suitable (S2) for upland rice (Iregun, Araromi, Itagunmodi, Owena, Olorunda, Oba and Egbeda); eight were moderately suitable (S2) for yam (Okemessi, Erin-Oke, Etionni, Iregun, Araromi, Itagunmodi, Owena and Egbeda) and for cassava five (Iregun, Araromi, Itagunmodi, Owena and Egbeda) were moderately suitable (S2). Similarly in Ilesha area, there was a general increase of 4.0% (1975 – 1986) and 0.3% (1986 – 2002) in the built-up areas; 2.3% (1975 – 1986) and 8.8% (1986 – 2002) in the fallow/crop land areas, 2.1% (1975 – 1986) and 2.6% (1986 – 2002) for Hill/Water areas; and a decrease of 8.4% (1975 – 1986) and 6.5% (1986 – 2002) for forest areas. Concordance between the two soil maps of the area was 54.9%. Fourteen soil series were identified out of which ten were of the same suitability class as those of Ife area. Of the remaining four series (Omo, Jago, Ondo and Irapa), two (Ondo and Jago) were marginally UNIVERSITY OF IBADAN LIBRARY iii suitable (S3) for maize and upland rice. Ondo series was moderately suitable (S2) while Omo and Jago series were marginally suitable (S3) for yam. Three (Omo, Ondo and Jago) soil series were marginally suitable (S3) for cassava while Irapa series was not suitable for any of the crops. Massive forest depletion and conversion of good agricultural lands to urban built-up existed in the area. The soil series identified were of varying degree of suitability in both areas for crop production. Keyword: Landuse/Landcover, Land Evaluation, Fertility capability classification, Remote Sensing.