Northern Guinea Savannah Research Articles

PREDICTING THE DECOMPOSITION RATE, MASS LOSS, AND NUTRIENT RELEASE OF SINGLE AND MIXED LEAF LITTER TYPES USING DECOMPOSITION MODELS IN THE NORTHERN GUINEA SAVANNAH OF NIGERIA

<p><strong>Background</strong>: This study presented a non-linear model to biologically describe the decomposition pattern, mass loss and nutrient release of four leaf litter species: <em>Khaya senegalensis </em>(African mahogany), <em>Mangifera indica </em>(Mango)<em>, Gmelina arborea</em> (Beechwood), <em>Eucalyptus camaldulensis</em> (River red gum) and a mixture of the leaf litters using the standard litter bag technique. <strong>Objective</strong>: To explore different mathematical decomposition decay models in evaluating the decomposition rate and the relationship between mass loss and chemical parameters of some selected trees in Nigeria's northern Guinea savannah. <strong>Methodology</strong>: The experiment was a Completely Randomized Design with three replications. Fifteen litter bags were randomly placed in the field and retrieved at intervals of 0, 14, 28, 42, 56, 84, and 112 days (16 weeks). Three non-linear models were used to estimate the decomposition rate of the litter. Pearson correlation analysis was used to determine the relationship between mass loss and chemical composition. <strong>Results</strong>: Decomposition pattern gradually increased from 7 % up to 78.5 % by week 0 to 16 weeks. The leaf litter of <em>Mangifera indica </em>had<em> </em>the highest mass loss (62.9 %), followed by the litter mixture (44.0 %), <em>Eucalyptus camaldulensis </em>(43.6 %), <em>Gmelina arborea</em> (40.5 %) and <em>Khaya senegalensis </em>(39.3 %). Single exponential model (<em>Adj R<sup>2</sup></em>=93.25-98.59%), double exponential model (<em>Adj R<sup>2</sup></em>=87.93-98.98%), and three parameters asymptotic negative exponential model (<em>Adj R<sup>2</sup>=</em>93.82-98.84%)<em>,</em> described the decomposition process efficiently. Correlation analysis of mass loss and chemical composition was highly significant (p ≤ 0.05), among all the leaf litter chemical properties, organic carbon, phosphorus, and nitrogen were the restraining factors. <strong>Implication</strong>: The mass loss was closely linked to the chemical properties of all the litter types. Among these properties, organic carbon and phosphorus were the limiting factors. <strong>Conclusion</strong>: We conclude that the single-leaf litter of <em>Mangifera indica</em> and <em>Khaya senegalensis</em> were superior in chemical composition, and decomposition than the mixed-leaf litter therefore they have the potential to enhancing soil fertility in the study area.</p>

Effects of sheep manure, plant population and nitrogen levels on growth and fresh fruit yield of chilli pepper (<i>Capsicum frutescence</i> l.) at Samaru, Zaria, Nigeria

Field experiments were conducted between 2004 and 2006 at the Institute for Agricultural Research Farm, Samaru Zaria in the Northern guinea savannah ecological zone of Nigeria, to study the response of chilli pepper (Capsicum frutescence L.) to sheep manure, plant population and nitrogen levels. Treatments evaluated consisted of four levels of sheep manure rates (0 t, 5 t, 10 t, and15 t ha-1), three plant populations (22,222; 44,444; and 66,666 plants ha1) and four rates of Nitrogen (0kg,60kg 120kg and 180 kg N ha1). The treatments were laid out in a split plot design and replicated three times. Result showed that application of sheep manure produced about significant increase in number of branches by 80%, similarly number of fruits increased by more than 600% and fresh fruit yields (Kg ha-1) recorded 57% increase over the control. Plant population was observed to significantly increase in the number of fruits per plant with 22,222 and 44,444plant/ha recording similar values, but higher number of fruits produced per plant than 66,666 plants ha-1 However, fresh fruit yield of Chilli pepper was not significantly influenced by plant population. The use of 120kgN ha1 resulted in increased number of branches, fruit per plant and fresh fruit yields by 57 and 60% respectively over non fertilized plants. Application of sheep manure at 10 t ha1, +44,444plants ha and 120kgN ha could be recommended for the production of chilli pepper under rain fed condition in Northern Guinea savannah.

Influence of temperature regimes on drought stress tolerance of cowpea genotypes in Northern Guinea savannah, Nigeria

Drought is a major constraint that affects cowpea production in Zaria, Nigeria. It is unpredictable, and occurs at any growth stage of cowpea. Changes in global climatic trendsare consistently narrowing the cowpea growing season in Northern Nigeria by graduallypushing its cultivation towards drought-prone, colder temperatures. The study aimed to elucidate foresight data on the tolerance of cowpea landraces to drought at cold and hottemperatures in a bid to harness available germplasm towards mitigating climatic changes.Seedling drought tolerance of four hundred and twenty-two (422) cowpea genotypes obtainedfrom farmers’ collection (308) and the International Institute of Tropical Agriculture (IITA) (114) was evaluated by adopting the wooden box method. The parameters evaluated were number of plants, plant height, number of trifoliate, leaf senescence, stem greenness, and recovery. The mean square values for all evaluated traits were significant (p ≤ 0.05). Leaf senescence progressed rapidly in cooler temperatures (6 oC - 18 oC). Interestingly, the recovery rate upon reintroduction of water after drought stress was higher in cold temperatures. The percentage recovery and stem greenness of drought-tolerant plants were positively associated with hot temperatures (22 oC - 36 oC). As cowpea production is pushed into colder planting season, the resilience shown by cowpea landraces in northern Nigeria are positive.

Productivity of Finger Millet (Eleusine coracana (L) Geartn) as Influenced by Pre-emergence Herbicides in the Northern Guinea savanna of Nigeria

Two field trials were conducted during 2011 and 2012 wet seasons at the Research Farm of the Institute for Agricultural Research, Ahmadu Bello University, Samaru Zaria (Lat. 11 o 11 1 N, Long. 07 O 38E and 686m above sea level), in the northern Guinea savannah zone of Nigeria, to evaluate the efficacy of pre-emergence herbicides on weed in finger millet. The treatments were atrazine (80WP) at the rates of (0.4, 0.8, 1.2 and 1.6 kg a.i/ha), RafT ® (500SC ) (Atrazine 250 g/l + Terbuthylazine 250 g/l ) at the rates of (0.25, 0.5, 0.75, and 1.0 kg a.i/ha) and Bullet (R) (700SC) (Atrazine 225 g/l + Terbuthylazine 225 g/l + Acetochlor 250 g/l) at the rates of (0.35, 0.75, 1.05 and 1.4 kg a.i/ha), hoe weeded control at 3 and 6 WAS and a weedy check. The treatments were laid out in a Randomized Complete Block Design (RCBD), replicated 3 times. The result shows that all the herbicide treatments significantly reduced weed dry weight than the weedy check. Application of atrazine at 0.8 kg a.i/ha or Raft at 0.5 kg a.i/ha gave lower weed dry weight and weed cover score than the hoe weeded control at 3 and 6WAS.While all the rates of Bullet, Raft at 0.75 and 0.1 kg a.i./ha and atrazine at 1.2 and 1.6 kg a.i./ha resulted in lower weed dry matter production which were comparable to hoe weeded control at 3 and 6WAS. Based on the results obtained from this study, 0.8 kg a.i./ha atrazine or 0.5 kg a.i./ha Raft gave season long weed control over hoe weeded check in finger millet with yield increase of 94.2 and 99.5%, respectively. The weedy checks reduced yield of finger millet by 66.7%.

Check List, Status, Threat and Perception of Some Wildlife Species in the Three Ecological Zones of Adamawa State, Nigeria

The study was conducted to produce the status of some wildlife species and determine the threat factors and perceptions of wildlife species in the three (3) ecological zones of Adamawa state. The study tool consists of a structured questionnaire, multi-stage and simple random sampling techniques used for data collection. Descriptive statistics with Kiringe and Okello (2007) model were used for data analysis. Results indicated that 70, 72 and 75 species of wildlife belonging to 36, 38 and 39 families were listed in the Sudan, Northern guinea and Southern guinea savannah zones, respectively. Most of the species in the three zones were either rare, endangered or have gone into local extinction. Only nine (9) species were common in the Sudan savannah zone, eleven (11) in the Northern guinea savannah zone and twenty-two (22) in the Southern guinea savannah zone. There were no abundant species in the three (3) zones. The threat factors which consistently showed the highest prevalent threat index were farming (26.0 - 45.4), hunting (32.2 – 55.4), logging (12.5 - 80) and grazing (11.2 – 17.0). The wildlife habitat susceptibility index was highest in the Sudan savannah zone (100%) but least in the Southern guinea zone (83%). Hunting (0.32 – 0.55), farming (0.26 – 0.45), logging (0.13 – 0.18) and grazing (0.12 – 0.17) consistently showed the highest mean score threat factors in the three zones. Similarly, hunting (0.00033 – 0.00010), farming (0.0023 – 0.00028), logging (0.0009 – 0.00020) and grazing (0.0009 – 0.00013) consistently showed the highest relative threat factors severity index in the three zones. Wildlife species were perceived as something good by the majority of respondents in the three (3) ecological zones. The study recommended the acquisition of skills in areas such as craft making, tailoring, shoe and bag making, motor mechanic, carpentry, mason and modern agricultural practice to prevent the local dwellers from hunting, indiscriminate expansion of agricultural land areas, illegal logging, grazing and wildfires. Policy on population control should be formulated by the government in view of increasing pressure on natural resources, which include wildlife resources. Adequate policy and institutional framework should be put in place for the purpose of management and conservation of wildlife resources at the grass root level. The state government should strengthen its conservation education programmes on the intrinsic value of wildlife to society and stiffer penalties for illegal poachers and hunters to mitigate further illegal harvesting of wildlife.

Yield and Yield Components of Finger Millet (Eleusine coracana (L) Geartn) as Influenced by Pre-Emergence Herbicides in the Northern Guinea Savanna of Nigeria

Two field trials were conducted during the 2011 and 2012 wet seasons at the research farm of the Institute for Agricultural Research, Ahmadu Bello University, 2012 Zaria (Lat. 11o 111N, Long. 07O38E and 686m above sea level) in the northern Guinea savannah zone of Nigeria, to evaluate pre emergence herbicides for weed control in finger millet (Eleusine coracana (L) Geartn). The trial consisted of 14 treatments. Atrazine (80WP) at rates of (0.4, 0.8, 1.2 and 1.6 kg a.i/ha), RafT® (500SC) (Atrazine 250 g/l + Terbuthylazine 250 g/l) at rates of (0.25, 0.5, 0.75, and 1.0 kg a.i/ha) and Bullet(R) (700SC) (Atrazine 225 g/l + Terbuthylazine 225 g/l + Acetochlor 250 g/l) at rates of (0.35, 0.75, 1.05 and 1.4 kg a.i/ha), hoe weeded control at 3 and 6 WAS and a weedy check. The treatments were laid out in a Randomized Complete Block Design (RCBD), replicated 3 times. In both years, all herbicide treatments and hoe weeded control at 3 and 6 WAS significantly increased yield components and yield, consistently across the two years, weedy check gave lower yield characters and yield. Based on the results obtained from this study, 0.8 kg a.i/ha of atrazine or 0.5 kg a.i/ha of Raft gave season long weed control over hoe weeded check in finger millet which resulted into higher grain yield.

Morphological variations in Nigerian Apis mellifera Linnaeus, 1758 populations in Guinea savannah agro-ecological zone

Apis mellifera Linnaeus, 1758 is one of the most economically valuable insects which plays significant role in human medicine, nutrition and crop pollination. The morphometric variations of honeybee from different locations of the southern guinea and northern guinea savannah ecological zone of Nigeria were studied. Fifteen morphological traits were measured for variation on six hundred (600) worker honeybee samples purposively collected from ten different locations within the ecological zone. Data collected were subjected to one-way Analysis of Variance (ANOVA), SNK test (α=0.05) and Pearson correlation between morphometric characters were determined. At the same time a dendrogram of morphological proximity based on the fifteen morphological features was constructed. Results showed that morphometry variation (p<0.05) existed within the honeybee population in the guinea savannah agro-ecological zone of Nigeria, high morphological similarities were observed in the tibia length of the hind leg and the thorax length. The honeybee samples were classified into two distinct morphoclusters (A and B). Honeybee samples within morphocluster A were closely related in terms of the examined morphometric features and geographic distance (CV=1.65). In contrast, within cluster B, honeybee samples were closely related despite the vast geographical distance (CV=3.30, p<0.05). The body length was significantly positively correlated with the leg size, while hind wing length was positively associated with the proboscis, abdominal, thoracic, body length and hooks. Morphometric variations found in A. mellifera of guinea agro-ecological zone could significantly impact conservation and future bee breeding programmes of Nigeria.

Effects of botanical extracts and antibiotic on incidence and severity of bacterial blight of cotton incited by Xanthomonas axonopodis pv. Malvacearum

A multilocational field trial was conducted to investigate the effect of some plant extracts (Bolanite aegyptica, Eucalyptus camaldulensis and Citrus aurantium) and a synthetic antibiotic (Streptomycin) on the incidence and severity of angular leaf spot on five cotton geno-types namely SAMCOT-8, SAMCOT-9, SAMCOT-10, SAMCOT-11 and SAMCOT-12 in Yola and Jalingo, both located in the northern guinea savannah zone of Nigeria. The experiment was carried out on a split-plot design having three replications with cotton genotypes on the main plots and plant extracts on the sub-plots. Data collected on the incidence and severity of the disease were analysed using the Generalized Linear Model procedure and means separation at 5% level of probability by Duncan Multiple Range Test. Findings of the study revealed that Streptomycin and Bolanite aegyptiaca were able to reduce the disease incidence by 18.12% from 58.69% in Yola at 13 WAS. In Jalingo however, B. aegyptiaca was found to have re-duced the disease severity from 52.12% to 19.69% at 13 WAS. SAMCOT-8 consistently recorded lower incidence and severity means in Yola and Jalingo of 47.96%; 59.12% and 40.82%; 39.70% while SAMCOT-12 recorded higher means of 53.29%; 59.82% and 48.03%; 46.70% respectively.

Simulation of the Optimum Planting Windows for Early and Intermediate-Maturing Maize Varieties in the Nigerian Savannas Using the APSIM Model

The Agricultural Production Systems Simulator (APSIM) model was calibrated and validated and used to identify the optimum planting windows for two contrasting maize varieties for three agro-ecologies in the Nigeria savannas. The model was run for 11 planting windows starting from June 1 and repeated every 7 days until 16 August using long-term historical weather data from the 7 selected sites representing three agro-ecological zones (AEZs). The evaluation with the experimental data showed that the model performance was reasonable and accurately predict crop phenology, total dry matter (TDM) and grain yield for both maize varieties. The seasonal planting date analysis showed that optimum planting windows for 2009EVDT and IWDC2SynF2 depend on the variety, agro-ecozones and sites. Planting from June 15 to 28 simulated the highest mean grain yield for both varieties in all the agro-ecologies. In the Southern Guinea savanna (SGS) where the length of growing season is 180–210 days, the best planting window was June 8–July 19 for 2009EVDT and June 8–July 26 for IWDC2SynF2 in Abuja. The planting window that gives attainable yield at Yelwa, is June 15–July 5 for 2009EVDT and June 8–28 for IWDC2SynF2. In the Northern Guinea savannah (NGS) where the length of growing season is 150–180 days, the optimum planting window is June 15–July 19 for both varieties at Zaria and June 8–July 19 for 2009EVDT and June 8–August 2 for IWDC2SynF2 at Sabon Gari. In the Sudan savannah (SS) where the growing season is 90–120 days, planting of 2009EVDT can be delayed up to the third week of July. For the medium-maturing variety, IWDC2SynF2, planting should be done by the first week of July. Though Yelwa is in the SGS, lower yields and narrower sowing windows were simulated for both varieties than for those of the other locations. This is probably due to the poor soil fertility in this location.

Response and Economic Efficiency of Broiler Chickens fed graded levels of Baker's Yeast (Saccharomyces cerevisiae) supplement

Two hundred and fifty-five day-old Ross White strain broiler chicks were used to evaluate the Response and economic efficiency of broiler chickens fed graded levels of baker's yeast (saccharomyces cerevisiae) supplement during the harmattan season in the northern guinea savannah zone of Nigeria. There were five treatment groups for both starter and finisher phases. The experiment lasted for eight weeks. Each treatment group had three replicates with 17 birds per replicate and fifty-five birds per group in a completely randomized design (CRD). Treatments 1, 2, 3, 4 and 5 contained 0.0, 0.5, 1.0, 1.5 and 2.0% SC respectively. Results of the starter phase showed significant (P<0.05) differences in terms of final weight gain and feed conversion ratio (FCR). Treatment groups fed the control diet (0.0%), 0.5% and 1% SC had the best final body weight and body weight gain during the starter phase. The FCR was significantly (P<0.05) higher in the treatment group fed 0.5%SC during the starter phase. Mortality was higher (11.76%) in the control group compared to other treatment groups in the starter phase. During the finisher phase, treatment group fed 1.0% SC had significantly (P<0.05) higher final body weight, body weight gain and FCR. Apparent digestibility of crude protein, crude fibre, ether extract, ash, dry matter and nitrogen free extract were better in treatment groups containing SC. The economic efficiency results of this study indicated that the birds fed 1.0% SC were more profitable compared to those fed the control diet. The net profit of the treatment group fed 1.0% SC was N 650.01 compared to the control (N554.35). This study concluded that the optimum inclusion level of Baker's yeast (Saccharomyces cerevisiae) in the diet of broilers starter was 0.5% and 1.0% for finisher diet for improved performance in terms of weight gain and feed conversion ratio (FCR). It is suggested that broiler chicken farmers should be encouraged to include Baker's yeast in the diet of broiler chickens for improved weight productivity and better feed utilization.

Response and Economic Efficiency of Broiler Chickens fed graded levels of Baker's Yeast (Saccharomyces cerevisiae) supplement

Two hundred and fifty-five day-old Ross White strain broiler chicks were used to evaluate the Response and economic efficiency of broiler chickens fed graded levels of baker's yeast (saccharomyces cerevisiae) supplement during the harmattan season in the northern guinea savannah zone of Nigeria. There were five treatment groups for both starter and finisher phases. The experiment lasted for eight weeks. Each treatment group had three replicates with 17 birds per replicate and fifty-five birds per group in a completely randomized design (CRD). Treatments 1, 2, 3, 4 and 5 contained 0.0, 0.5, 1.0, 1.5 and 2.0% SC respectively. Results of the starter phase showed significant (P<0.05) differences in terms of final weight gain and feed conversion ratio (FCR). Treatment groups fed the control diet (0.0%), 0.5% and 1% SC had the best final body weight and body weight gain during the starter phase. The FCR was significantly (P<0.05) higher in the treatment group fed 0.5% SC during the starter phase. Mortality was higher (11.76%) in the control group compared to other treatment groups in the starter phase. During the finisher phase, treatment group fed 1.0% SC had significantly (P<0.05) higher final body weight, body weight gain and FCR. Apparent digestibility of crude protein, crude fibre, ether extract, ash, dry matter and nitrogen free extract were better in treatment groups containing SC. The economic efficiency results of this study indicated that the birds fed 1.0% SC were more profitable compared to those fed the control diet. The net profit of the treatment group fed 1.0% SC was N 650.01 compared to the control (N554.35). This study concluded that the optimum inclusion level of Baker's yeast (Saccharomyces cerevisiae) in the diet of broilers starter was 0.5% and 1.0% for finisher diet for improved performance in terms of weight gain and feed conversion ratio (FCR). It is suggested that broiler chicken farmers should be encouraged to include Baker's yeast in the diet of broiler chickens for improved weight productivity and better feed utilization.

Parkland Trees under Severe Drought: An Assessment of Species Diversity and Abundance across Three Agroecological Zones of Northern Nigeria

The appraisal of tree stand structure on parklands is crucial for sustainable agroforestry management decisions, particularly in the drylands of Nigeria. An assessment of tree species distribution in farm plots across the three driest Agroecological zones (AEZ) within Northern Nigeria was performed to determine diversity and abundance in a changing climate. The AEZ include Sudan savannah (SS), Northern Guinea savannah (NGS) and Southern Guinea savannah (SGS). In each AEZ, 3 transects were laid per village and a total of 4 sample plots were located along each transect. Tree bole diameter of all the sampled woody perennials with dbh ≥ 10 cm was measured and identified to species level. The measurement and computation include basal area, species relative density and dominance as well as the important value index (IVI). Results showed that across the AEZs, Parkia biglobosa trees had the highest IVI but reduces from the driest zone, SS (50.25%) through the transitional zone, NGS (38.45%) to the wettest AEZ, the SGS (35.43%). The lowest IVI recorded were in Gliricidia sepium (0.62%), Psidium guajava (2.89%) and Eucalyptus camaldulensis (1.83) in the SGS, NGS and SGS respectively. Parkia biglobosa and Mangifera indica dominated the landscapes and are classified as the landscapes’ habitat generalists. Despite the low organic matter content, Sudan savannah had more diverse species on its farm landscapes than the two other AEZ but with less tree popuplation density. The potential contribution of agroforestry parkland trees to agrobiodiversity in reducing drought and improving soil fertility is essential for sustainable agricultural productivity and landscape restoration.

Effect of seed rate and varieties on yield and yields components of cowpea (Vigna unguiculata (l.) Walp.) in northern guinea savannah region of Nigeria.

Introduction: The effect of seed rate on three cultivars were investigated in field trial in two successive seasons (2019/20 and 2020/21) at northern guinea savannah region of Nigeria, to determine the optimum seed rate for yield and yield components of cowpea. SAMPEA-11, SAMPEA-12 and Kanannado Varieties were sowed in four seed rates of 6, 12, 18 and 24 kg ha-1. Methods: The experiment was laid out in a randomized complete block design (RCBD) in four replications. Results: The results showed that, increased seed rate significantly increased seed yield per unit area, however the number of pods per plant, seed yield per plant and harvest index reduced with increased seed rate. Conclusion: Among the improved variety, SAMPEA-12 was outstanding for earliness especially in drought prone areas.

Effect of the Depth of Insertion of the Thermometer on the Rectal Temperature of Donkeys During the Hot-Dry Season in a Tropical Savannah

The objective of the present study was to evaluate the effect of the depth of insertion and environmental parameters on the rectal temperature (RT) in donkeys during the hot-dry season in a tropical savannah zone of Nigeria. The experimental subjects were comprised of thirty donkeys divided into three groups based on age: group I, 10 foals (40.67 ± 2.20 kg; 1.50 ± 0.02 months); group II, 10 yearlings (91.53 ± 0.54 kg; 1.51 ± 0.01 years); and group III, 10 adults (140 ± 0.71 kg; 8.03 ± 0.06 years). Each group was divided into 5 male and 5 female donkeys. Measurements of the RT were recorded with a digital thermometer probe (model HI935007, Hanna Instruments), which was inserted into the rectum at varying depths of 3.5, 7, 10.5, and 14 cm in the same animal in each group. There was a gradual increase in the RT in donkeys as the depth of insertion was increased from 3.5 cm (36.60°C) to 14 cm (38.40°C). Data obtained from the study were subjected to repeated-measures analysis of variance, followed by Tukey's post-hoc test to compare mean values between different depths of RT measurements. Overall, there was a variation in the RT by the depth of insertion with the shallow depth of 3.5 cm having a lower RT than the depths of 7, 10.5, and 14 cm. The variation of the RT observed in donkeys showed that there is need to standardize the probe-insertion depth in veterinary clinical practice for accurate measurement of the RT in donkeys in the Northern Guinea savannah zone of Nigeria.

Adoption of improved maize varieties in northern Guinea Savannah of Borno State, Nigeria

This study examined the adoption of improved maize varieties in northern Guinea Savanna of Borno State. Primary data were collected by using structured interview schedule. Two hundred maize farmers were systematically selected from. Percentage and logit were used for data analyses. Overall adoption rate was 89.0%. Coefficient of socio-economic and institutional factors such as extension contact (0.0360), farm size (0.2319), education level (0.0460), access to credit (0.6363) and age (0.7619) were found to be significant (P≤0.01) and positively influencing adoption of improved maize varieties. Household size (0.2708) and income level (0.3285) were also significant (P≤0.05) and positively related to likelihood of adoption of improved maize varieties. Non-availability of technology (99%), high cost of technology (92%) and high cost of labour (88%) were the major constraining factors to adoption of improved maize varieties. Community seed production should be encouraged and promoted to facilitate easy access to improved seeds by farmers. The extension system should be strengthened, a policy, which provides adequately trained and equipped extension workers for disseminating extension messages to farmers, re-strengthening of community based organizations and seed companies to introduce labour saving tools like planters and harvesters etc.Keywords: Adoption; improved maize; guinea savannah

Efficiency of Food-Based Attractants for Monitoring Tephritid Fruit Flies Diversity and Abundance in Mango Systems Across Three West African Agro-Ecological Zones.

Food baits are effective and widely used tools for monitoring diversity and abundance of tephritid fruit flies. Four food-baits-Nulure, BioLure, Mazoferm at 3 and 6%, and Torula yeast-were used in multi-lure traps over a 4-yr period in mango orchards in three Benin agro-ecological zones (AEZ) representing a large swath of environments in western Africa. Twelve tephritid fruit fly species were captured during the trials, with the highest richness in the Forest Savannah Mosaic (FSM), followed by the Southern Guinea Savannah (SGS), and the Northern Guinea Savannah (NGS) AEZ. Despite previous reports of displacement, the native species Ceratitis cosyra remained the dominant tephritid species in mango orchards in the NGS, with the invasive and exotic species Bactrocera dorsalis dominating the tephritid fauna in the SGS and FSM. Torula yeast captured the greatest number of fruit flies in each AEZ. Mazoferm-3% captures were similar to Torula yeast, except for lower captures in the NGS where it tended to harden. The rank order of relative efficiency indices (REI) of the food baits (relative to Torula yeast) is Mazoferm-3% > Nulure > Mazoferm-6% and BioLure. The latter captured more Ceratitis spp. than all the other baits, particularly at very low Ceratitis spp. abundance. To our knowledge, the study is the first to report relative efficiency indices for the selection of food baits in monitoring diversity and abundance of fruit flies. Ecological and practical implications for the use of food baits in comparison with male lures are discussed.

Detection and diversity of maize yellow mosaic virus infecting maize in Nigeria.

Maize yellow mosaic virus (MaYMV; genus Polerovirus; family Luteoviridae) was recently characterized from maize in China and subsequently detected in mixed infection with sugarcane mosaic virus (genus Potyvirus; family Potyviridae) in sugarcane and itch grass in Nigeria. This study was conducted to understand the status and genetic diversity of MaYMV in maize fields in the northern guinea savannah region of Nigeria. A survey was conducted in 2017 and maize (n = 90) and itch grass (n = 10) plants suspected of virus infection based on appearance of mosaic and/or yellowing symptoms were sampled in Kaduna (n = 65) and Katsina (n = 35) states. The samples were screened individually by reverse transcription polymerase chain reaction using the genus-specific primers targeting poleroviruses and potyviruses Pol-G-F and Pol-G-R primers encompassing the partial P1-P2 fusion protein and coat protein genes of poleroviruses and primer pair CI-For & CI-Rev encompassing the partial cylindrical inclusion proteins of most potyviruses. A subset of amplified DNA fragments was cloned, Sanger-sequenced, and the obtained sequences were bioinformatically analyzed along with corresponding sequences from GenBank. The ~ 1.1Kb polerovirus fragment was detected in 32.2% (29/90) of the maize samples while all 10 itch grass samples tested negative. BLASTN analysis of sequences derived from six polerovirus samples confirmed the virus identity as MaYMV. In pairwise comparisons, the MaYMV sequences derived in this study shared 97-99% nucleotide identity with sequences of other MaYMV isolates available in the NCBI GenBank. Phylogenetic analysis revealed the segregation of global MaYMV sequences into three host-independent clusters with pattern of geographic structuring.

Prevalence and Genome Characterization of Field Isolates of Sugarcane Mosaic Virus (SCMV) in Nigeria.

Maize and sugarcane are two economically important crops often grown in adjacent fields or co-cultivated in the northern guinea savannah agroecological zone, a major cereal production region of Nigeria. This study was conducted to determine the prevalence of mosaic disease in sugarcane and maize fields in the northern guinea savannah agroecological zone and to molecularly characterize the associated sugarcane mosaic virus (SCMV, genus Potyvirus) isolates. Surveys were conducted from June to July 2015, and sugarcane mosaic disease (SCMD) incidence was assessed across 21 farmer's fields. Mean SCMD incidence varied across states with ∼82% (308/376), ∼66% (143/218), and ∼67% (36/54) recorded in Kaduna, Kano, and Katsina states, respectively. RT-PCR analysis of 415 field-collected samples using genus-specific primers confirmed potyvirus infection in 63.7% (156/245) of sugarcane, 29.7% (42/141) of maize crops, and 45% (13/29) of itch grass samples. Cloning and sequencing of gene-specific DNA amplicons from a subset of 45 samples (sugarcane = 33, maize = 9, itch grass = 3) confirmed their specificities to SCMV. Phylogenetic analysis of the partial gene sequences showed that they all belong to a single monophyletic clade of SCMV. These results were supported by analysis of complete polyprotein sequences of representative maize and sugarcane isolates from Nigeria. Both isolates shared 94.9%/97.3% complete polyprotein nucleotide (nt)/amino acid (aa) identities with each other and 75.2%/97.6% nt/aa identities with corresponding sequences of global SCMV isolates. The detection of identical populations of SCMV isolates in both crop species and a weed host suggests possible vector mediated interspecies spread within cereal landscapes in the study area with implications for the integrated and sustainable management of SCMD in cereal cropping systems in Nigeria.

Yield and yield components of intercropped dual-purpose lablab and cowpea with maize of contrasting maturities

Intercropping is a way to intensify agricultural land use. Cowpea is an important crop in the traditional farming systems in northern Nigeria because it serves to provide food and feed. Although lablab has potential to function in these ways, it remains an underutilized crop because among other factors, there is dearth of information on its incorporation into the system by way of intercropping it with the major cereal crops. A field trial was conducted at Samaru (11o 11’N, 07o 38’E, 686 m asl) in northern Guinea savannah of Nigeria, to evaluate the relative yield and yield components of dual-purpose lablab and cowpea cultivars when gown sole and when intercropped with maize of contrasting maturities. The experiment was laid out in a split-plot design with four replications. The experiment consisted of early maize maturing cultivar (TZE COMP. 5 W) and a late maize maturing cultivar (TZL COMP. 1 SYN). Cropping system (intercropping and sole cropping) was assigned to the main plot and crop cultivar (lablab: ILRI 4612, NAPRI 2 and cowpea: IT89KD- 288, IT99K-241-2) was assigned to subplots. Results showed that intercropping cowpea or lablab into early maturing maize cultivar was more productive than intercropping into late maturing maize cultivar for number of pods (74.4 vs. 63.9), harvest index (0.22 vs. 0.20), grain yield (575.7 vs. 441.0) and fodder yield (2075.4 vs. 1758.2) for the legumes. Lablab cultivars had superior performance than cowpea for number of pods (113.5-114.2 vs. 81.1-81.5) and fodder yield (2968.9-3042.3 vs. 1725.4-1795.9 kg ha -1 ) whereas cowpea cultivars had superior performance than lablab for harvest index (0.29 vs. 0.17) and grain yield (802.3-833.9 vs. 587.8-632.4 kg ha -1 ), meaning that both legumes have potential in providing food and feed with lablab producing more fodder and cowpea more grain. Land equivalent ratio showed that intercropping advantage was higher when lablab and cowpea were intercropped with early maturing maize cultivar (1.34, 1.24) than with late maturing maize cultivar (1.10, 1.15). It is recommended that for higher lablab or cowpea/maize productivity in an intercrop, farmers should intercrop dual-purpose cultivars of these crops with maize of earlier maturities. Keywords: maize, lablab, cowpea, grain yield, fodder yield

Blood profile of growing dromedary camel fed varying levels of dried Gawo (Faidherbia albida) leaves in the Northern Guinea Savannah of Nigeria

This study was carried out to evaluate the effect of dried Faidherbia albida leaves on some haematological and biochemical parameters of growing dromedary camels. Four male camels weighing on average 228.51 kg were randomly allocated to 4 diets containing 0, 10, 20 and 30% dried F. Albida leaves in a 4 x 4 Latin Square Design. Normal haematological (whites blood cells, Red blood cells, Packed cells volume and haemoglobin concentration), different Leucocytes count (Neutrophils, Esinophils, Lymphocytes, Monocytes, Basophils) and Serum biochemical parameters have been determined. Statistical analysis showed there were significant differences in all the parameters. However, the values were within the normal reference values. Hence, dried F. albida leaves can be included in the diets of camels up to 30% without detrimental effect on their blood profile in the northern guinea savannah of Nigeria.