Acacia Sieberiana Research Articles

Variable intraspecific response to climate change in a medicinally important African tree species, Vachellia sieberiana (DC.) (paperbark thorn).

Climate change is predicted to disproportionately impact sub-Saharan Africa, with potential devastating consequences on plant populations. Climate change may, however, impact intraspecific taxa differently. The aim of the study was to determine the current distribution and impact of climate change on three varieties of Vachellia sieberiana, that is, var. sieberiana, var. villosa and var. woodii. Ensemble species distribution models (SDMs) were built in "biomod2" using 66, 45, and 137 occurrence records for var. sieberiana, var. villosa, and var. woodii, respectively. The ensemble SDMs were projected to 2041-2060 and 2081-2100 under three general circulation models (GCMs) and two shared socioeconomic pathways (SSPs). The three GCMs were the Canadian Earth System Model version 5, the Institut Pierre-Simon Laplace Climate Model version 6A Low Resolution, and the Model for Interdisciplinary Research on Climate version 6. The suitable habitat of var. sieberiana predominantly occurs in the Sudanian and Zambezian phytochoria while that of var. villosa largely occurs in the Sudanian phytochorion. The suitable habitat of var. woodii mainly occurs in the Zambezian phyotochorion. There is coexistence of var. villosa and var. sieberiana in the Sudanian phytochorion while var. sieberiana and var. woodii coexist in the Zambezian phytochorion. Under SSP2-4.5 in 2041-2060 and averaged across the three GCMs, the suitable habitat expanded by 33.8% and 119.7% for var. sieberiana and var. villosa, respectively. In contrast, the suitable habitat of var. woodii contracted by -8.4%. Similar trends were observed in 2041-2060 under SSP5-8.5 [var. sieberiana (38.6%), var. villosa (139.0%), and var. woodii (-10.4%)], in 2081-2100 under SSP2-4.5 [var. sieberiana (4.6%), var. villosa (153.4%), and var. woodii (-14.4%)], and in 2081-2100 under SSP5-8.5 [var. sieberiana (49.3%), var. villosa (233.4%), and var. woodii (-30.7%)]. Different responses to climate change call for unique management and conservation decisions for the varieties.

Impact of Human Activities on Woody Vegetation in Gallery Forests in the Mandara Mountains (Far North, Cameroon).

This study was conducted in the Mandara Mountains in Cameroon and aimed to assess the effects of human activities on woody vegetation in gallery forests, based on floristic inventories and observations made by the government. Firstly, the inventories were carried out in 150 plots of 1000 m2 each, installed on the banks of watercourses following the band of plant formations. In each plot, woody species were counted and those showing at least one sign of degradation were noted. Secondly, the survey was conducted in 18 administrative structures made up of delegations (MINFOF, MINADER, MINEPDED, and MINEPIA) and town halls. One hundred woody species, grouped into 63 genera and 30 families, have been inventoried, in which 45 species showed at least one sign of damage caused by human being. The species most affected are Anogeissus leiocarpus (67 stems), Azadirachta indica (46 stems), Diospyros mespiliformis (43 stems), Acacia albida (42 stems), Andira inermis (30 stems), Acacia sieberiana (23 stems), Khaya senegalensis (19 stems), Ficus sycomorus (13 stems), and Acacia polyacantha (10 stems). The most recurrent activity in the gallery forests is pruning (212 stems), followed by cutting (93 stumps), then picking (71 individuals). However, there are fewer debarked trees (11) and trees with fire trail (6). According to the responses provided, logging (77.78%), agriculture (72.22%), population growth (44.44%), grazing (33.33%), and bush fires (33.33%) are the main causes of the degradation of plant formations in the Mandara Mountains. These main factors could have a negative impact on biodiversity if appropriate integrated management measures are not taken. To maintain these vital ecosystems, an integrated management plan must be put in place, limiting human activities to a minimum.

Feeding Habits and Activity Patterns of Grivet Monkey (Chlorocebus aethiops L.) in Batiero Church Forest, Northern Ethiopia

Grivet monkeys (Chlorocebus aethiops) are restricted to fragmented forests where food and space are limiting factors. The study investigated the feeding and activity patterns of grivet monkeys in Batiero Church Forest, northern Ethiopia, using focal and scan sampling techniques. Both focal and scan animal sessions lasted 15 min, with 5 min rest intervals between sessions. During the early dry season, grivet monkeys mainly fed on Acacia sieberiana (26.5%) and Juniperus procera (17.5%). Dry season food selection was significantly different, J. procera (20.5%), Acacia mearnsii (15.6%), A. sieberiana (14.2%), and Cyperus bulbosus (12.7%). The predominant plant parts eaten were seeds (42.6% and 33.3% in early dry and dry seasons, respectively) followed by leaves (34.5% and 22.5% in early dry and dry seasons, respectively). The activity patterns showed no significant seasonal variation, and the most frequent activity was feeding (33.3% and 32.6%, in early dry and dry seasons, respectively). The preferred food source tree species are threatened, and the survival of the grivet monkeys depends on the conservation of indigenous plants and trees.

Chemical Composition and Evaluation of Anti-tyrosinase and Anti-Oxidative Effects of Topical Cream Formulation from Acacia sieberiana, Vitellaria paradoxa and Beeswax

Skin diseases can get natural therapies from medicinal plant-based products. In this study, a topical cream was formulated from ethanol extract of Acacia sieberiana, beeswax and Vitellaria paradoxa (shea) butter. GC-MS characterization with co-injection of the topical cream revealed Stearic acid (31.43%), Palmitic acid (23.15%), Oleic acid (21.44%) and Linoleic acid (16.20%) as the major components. Seven phenolic conpounds were identified and quantified by HPLC- DAD and Ferulic acid (12.81±0.26 mg/g) was the most abundant. The cream showed good antioxidant properties evaluated through ?-Carotene-linoleic acid assay, DPPH• radical scavenging, ABTS•+ assay, CUPRAC assay, and metal chelating assay. The cream had higher activity in the DPPH• assay (IC50 = 32.10±0.84 µg/mL), ABTS•+ assay (IC50 = 22.49±0.62 µg/mL) and CUPRAC assay (IC50 = 49.27±0.79 µg/mL) than ?-Tocopherol. The antioxidant effects are an indication that the cream can reduce oxidative stress on the skin including aging, carcinogenesis and inflammation. At 100 µg/mL, the topical cream showed tyrosinase inhibition of 48.23±0.87% regarded as relatively good compared to the standard tyrosinase inhibitor kojic acid, which showed 79.50±0.32% inhibition at the same concentration. The cosmetic cream was able to inhibit the melanin production rate-limiting enzyme, tyrosinase, indicating that it can control hyperpigmentation and skin spots.

Nodulation alleviates the stress of lower water availability in Vachellia sieberiana

The genus Vachellia (Fabaceae) has a pan-tropical distribution and numerous Vachellia species are currently observed to be expanding their indigenous ranges and/or are invasive. Most Vachellia species have the capacity to enhance nitrogen uptake via an N2-fixing rhizobial mutualism that manifests in specialized root nodule structures enabling the catalysis of atmospheric N2 into a plant useable form. Improved understanding of nodulation may provide new insight to the changing patterns of ecological success of Vachellia species. Here, we investigated how the seedling growth, allometry and nodulation of two common Vachellia species, the arid Vachellia erioloba and the mesic Vachellia sieberiana, responded to varied levels of water availability. Seedlings were grown at 4%, 8% and 16% soil moisture content (SMC) for four months. The seedling growth and allometry of V. erioloba was unresponsive to changing water availability, and no nodulation was observed. The allometry of V. sieberiana was responsive to changing water availability and nodulation was observed; with the highest nodule biomass and growth rate recorded at 4% SMC. These patterns suggest that V. erioloba does not require the rhizobial mutualism, possibly due to lower competitive interactions between woody plants and grass in the arid savanna. Whereas, due to the competitive vegetation interactions typical in the mesic savanna, N2- fixation via nodule development could provide V. sieberiana a competitive advantage over grass not only in limited N conditions, but also during periods of lower water availability.

Nutrient addition, fire and grass competition affects biological nitrogen fixation in Vachellia sieberiana, and associated soil respiration

Biological nitrogen fixation (BNF) by woody legumes is likely to vary due to factors such as nutrient availability, fire and grazing. BNF may also alter soil properties by increasing soil fertility, consequently affecting rates of soil respiration. Given the widespread increase in woody plant density in southern African savannas, we investigate the factors influencing BNF in a common encroaching woody legume, Vachellia sieberiana. We conducted a pot experiment using a matrix of grass and seedlings of V. sieberiana. We then assessed the effects of increased nutrient availability (nitrogen (N) and phosphorous (P)) through fertilizer addition, as well as simulated fire and grazing on the rate of BNF, the number and weight of root nodules, and soil respiration. We found a significant decrease in BNF with fertilizer addition, and increases in BNF after fire application. Soil respiration increased with fertilizer addition and decreased after fire application. Grazing had no independent effect on any of the response variables. However, decreased grass biomass, and therefore reduced competitive interactions between tree seedlings and grasses, resulted in increased BNF across all treatments. Furthermore, we found that larger woody seedlings achieved higher rates of BNF, with a positive correlation between the rate of BNF and both the number and weight of root nodules. We conclude that BNF in V. sieberiana is facultative and strongly influenced by grass competition, with differing responses to varying environmental factors. Fertilizer addition suppresses BNF because the presence of readily available N negates the costs of fixation. V. sieberiana seedlings compensated for N lost by fire application by increasing BNF. Soil respiration was found to increase with fertilizer addition, possibly due to higher carbon (C) inputs into the soil. Conversely, fire reduced soil respiration by removing biomass, and thus reduced C input into the soil.

Phenolic profiles, antioxidant, antiquorum sensing, antibiofilm and enzyme inhibitory activities of selected Acacia species collected from Benin

Gum arabica is a local commercial nutraceutical and food preservative collected mostly from acacia plants. HPLC-DAD analysis identified gallic acid, syringic acid, ferulic acid, coumarin, rutin and rosmarinic acid in hydroethanol extracts of all three acacia species with ferulic acid being the most abundant component in Acacia ataxacantha (45.25 ± 0.33 mg/g) Acacia sieberiana (130.3 ± 0.65 mg/g) and Acacia nilotica (125.50 ± 0.51 mg/g). Extracts displayed good antioxidant capacities in β-carotene-linoleic acid, DPPH•, ABTS•+, CUPRAC and metal chelating assays and extracts were more active than the standards used in the DPPH•, ABTS•+ and CUPRAC assays. Extracts inhibited violacein production in Chromobacterium violaceum CV12472 at MIC and sub-MIC concentrations as well as quorum sensing in C. violaceum CV026 under externally supplied acylhomoserine lactone. The extracts showed antimicrobial activity with MIC values ranging from 0.1562 mg/mL to 2.5 mg/mL on Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, Salmonella Typhi, Escherichia coli and Candida albicans with excellent biofilm inhibition at MIC and sub-MIC concentrations especially against E. coli. Extracts showed inhibitions on some enzymes with A. Sieberiana and A. Nilotica having very good anticholinesterase, antidiabetic (α-glucosidase and α-amylase) and antiurease activities. The results indicate the relevance of acacia in food applications.

The antiproliferative extract from the leaves of Acacia sieberiana var. woodii (Fabaceae) is harmless as evidenced by acute and subacute toxicity studies in rats

• Oral acute and sub-acute toxicities of Acacia sieberiana were evaluated in rats. • No major signs of toxicity were observed in the liver and kidneys. • Slight signs of toxicity were observed at a dose of 1000 mg/kg body weight/day. • Acacia sieberiana bark is harmless at lower dose. Acacia sieberiana DC. var. woodii or Vachellia sieberiana var. woodii (Burtt Davy) Kyal. & Boatwr. is a plant used in Cameroon to treat several diseases such as bilharzia, tapeworm, hemorrhage, rheumatism, gonorrhea, syphilis, ophthalmia, stomachache, urethral diseases, oedema, and diarrhea. The methanol extract of Acacia sieberiana leaves (ASL) has been reported previously for its antiproliferative activity towards several human cancer cell lines. This research aims to evaluate the acute toxicity and subacute toxicities of ASL. The acute toxicity was carried out according to established protocol. The crude extract (ASL) was administered orally to female rats at a single dose of 5000 mg/kg body weight (b.w.) and the animals were observed for any behavioral changes or mortality. In the subacute toxicity study, ASL was orally administered daily to male and female rats at different doses (250, 500, and 1000 mg/kg b.w.) for 28 days. During these treatment days, the animals were observed for any appearance of toxicity symptoms. Following the treatment period, animals were sacrificed for hematological, biochemical, and histopathology analysis. The acute toxicity study revealed neither behavioral disturbances nor death in rats. The lethal dose (LD 50 ) body weight was greater than 5000 mg/kg b.w. Subacute administration of ASL showed significant variations ( P > 0.05) of body weight, the relative weight of organs, some hematological and biochemical parameters. Histopathological examinations showed no remarkable pathological changes on the kidney and slight cell lysis in the liver. This study shows that ASL is non-toxic, but that caution should be taken in case of the prolonged consumption of the botanical at a high dose (1000 mg/kg b.w.).

What is in a name? Scientific name changes of potentially poisonous plants and fungi in South Africa

Changes over the past five decades in the scientific names of some potentially poisonous plants and toxigenic fungi in South Africa are briefly reviewed. Some of the reasons why taxonomists change names are highlighted. In recent years, DNA sequencing data have contributed considerably towards establishing phylogenetic relationships among plants, often resulting in changes in generic circumscription and, consequently, the names of species. Philosophical differences between the phylogenetic and the evolutionary schools of plant classification are briefly explained as these may manifest as different classifications for the same group of plants. Although choice of classification remains the prerogative of the end-user of plant names, in this review, the classifications for plants currently adopted by the South African National Biodiversity Institute (SANBI) in its online database, Plants of Southern Africa (POSA), were followed. Noteworthy generic changes include Pachystigma to Vangueria, Homeria to Moraea, and Urginia to Drimia. Following much controversy, the species native to southern Africa that were formerly treated as Acacia are now classified in either Vachellia or Senegalia, with the genus name Acacia being retained for the mainly Australian members of the group, the latter commonly known as wattles. Former southern African members of Acacia implicated in poisoning include Vachellia erioloba(camel thorn), Vachellia sieberiana var. woodii (paperbark thorn), and Senegalia caffra (common hook thorn).

Acacia sieberiana (Fabaceae) attenuates paracetamol and Bile Duct Ligation-Induced hepatotoxicity via modulation of biochemical and oxidative stress biomarkers.

Background: The plant Acacia sieberiana (Fabaceae) is traditionally used to manage hepatitis. This research work aims to investigate the hepatoprotective effectiveness of root bark extract of Acacia sieberiana (ASE) against paracetamol (PCM) and bile duct ligation (BDL)-induced hepatotoxicity. The phytochemical and median lethal dose (LD50) investigations were conducted. The rats were pre-treated with the ASE (250, 750, and 1,500 mg/kg) once daily via oral route for 7 consecutive days. On the 8th day, liver injury was initiated by PCM administration (2 g/kg). Similarly, in the BDL-induced liver injury, the animals were administered ASE (125, 250, and 380 mg/kg) intraperitoneally for 7 consecutive days. After 24 h, blood samples and hepatic tissues were obtained for biochemical and histopathological investigations. Results: Phytocomponents determination revealed glycosides, triterpenes, glycosides, saponins, tannins, flavonoids and alkaloids. The oral and intraperitoneal LD50 values of the ASE were >5,000 and 1,300 mg/kg, respectively. The ASE efficiently (p < 0.05) decreased the alanine transaminase (ALT) and aspartate transaminase (AST) levels and elevated the albumin and total protein (TP) levels. The direct bilirubin effectively (p < 0.05) decreased at 750 mg/kg. Besides, the extract efficiently elevated the glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT) in relation to the PCM hepatotoxic group. Also, the malondialdehyde (MDA) concentration was reduced by the ASE. Meanwhile, in the BDL–induced liver injury, the ASE remarkably (p < 0.05) declined the AST, ALP, bilirubin,and MDA. Besides, there was effective (p < 0.05) elevation in SOD, GPx and CAT in the ASE-treated groups. The morphology of liver tissue was preserved at 125 and 250 mg/kg ASE groups from BDL-induced necrosis and vascular congestion. Conclusion: The study shows that the ASE has hepatoprotective actions against liver damage by possible modulation of biochemical and oxidative stress biomarkers.

Rapid germination and development of Acacia sieberiana DC in vitro

Acacia sieberiana is an ecological and economical important forest tree. The plant has poor germination due to dormancy; therefore, in vitro culture can provide a fast supply of plantlets and can be a basis for further biotechnology research. The effect of sodium hypochlorite, Murashige and Skoog (MS) medium, sucrose and cytokinin were investigated. The results indicated that all the treatments induced significant (P &lt; 0.05) effects on germination and seedling development depending on their concentrations. Germinates free of contamination were established successfully with all the concentrations of sodium hypochlorite, however, the germination was reduced as the concentration increased. A higher germination rate of 98.3% was attained with full MS strength and 3% sucrose concentration. The highest germination percentage obtained was 100% with 2 mg/L thidiazuron. The maximum shoot length (13.5 cm) and seedling dry weight (0.49 g) were recorded on full MS medium while the maximum root length (13.4 cm) was obtained on ½ MS strength. However, when full MS medium augmented with 5% sucrose enhanced shoot length and dry weight to (14.2 cm) and (0.5 g), respectively. While the highest root length (10.2 cm) was obtained by 3% provided in full MS medium. Application of cytokinins improved the number of node and dry weight of seedlings to 6.9 nodes with 4 mg/L thidiazuron and 0.54 g by 2 mg/L benzyladenine. The present study describes the establishment of in vitro seed germination and seedling growth system for A. sieberiana for the first time.

Evaluation of soil physico-chemical properties as affected by canopies of scattered agroforestry trees on croplands

Agroforestry tree species play an important role in improving soil fertility. Though studies have confirmed that different species show different potentials to improve soil fertility, it is difficult to compare them as the studies were conducted in different areas. The potential for different tree species to improve soil fertility on croplands in northern Ethiopia is not known. The objectives of this paper are to determine the effects of presence or absence of agroforestry tree species on soil physico-chemical properties and the effect of distance from the tree trunk on the same soil physico-chemical properties. Sixty composite and undisturbed soil samples from beneath canopies and outside canopies and 90 composite and undisturbed soil samples from three different distances from tree trunks were collected. The results revealed that soil bulk density, soil moisture, soil organic carbon (SOC), total nitrogen (TN), available phosphorus (Av.P), exchangeable potassium (Exch.K) and soil organic carbon stock (SOCS) were significantly (p < 0.05) different between soils beneath canopies and outside canopies as well as at different distances from the tree trunk. Soils around these agroforestry tree species have increased SOC, TN, Av.P, Exch.K and SOCS by 11.9 to 91.5%, 22.2 to 125.0%, 31 to 71%, 32 to 151.6% and 15.2 to 90.9%, respectively, compared to soils outside tree canopies. Faidherbia albida (Delile) A.Chev. has the highest potential for soil fertility compared to Balanites aegyptiaca (L.) Delile, Cordia africana Lam., Ziziphus spina-christi (L.) Desf., Acacia sieberiana DC and Croton macrostachyus Hochst. ex Delile. This study could provide useful information for soil fertility management and farmers’ decision-making when selecting tree species. The findings of this study imply that scattered trees on croplands significantly improve soil fertility and reduce the need for external fertiliser inputs.

Experimental drought suppresses grass productivity and passive warming promotes tree sapling performance: Insights from African savanna species

Warming as well as increasingly frequent and severe droughts under climate change are expected to have global impacts on vegetation. We examined the independent and interactive effects of water availability and warming on the growth of savanna grasses and tree saplings. We used a widespread C4 grass species Eragrostis curvula, and a native woody encroacher, Vachellia sieberiana, in South Africa. We simulated a typical savanna microhabitat by planting tree species within a grass matrix, in 45 L containers. Watering treatments were applied weekly as drought (minus 40% of the long-term average), normal (same amount as the long-term average), and excess (addition of 40% of the long-term average). Passive warming was achieved using open-top chambers. We found that water availability was the main limiting factor for grass productivity, with low grass biomass attained under drought treatments. Warming had no significant effect on grass productivity, but had a large positive effect on tree sapling growth and performance when coupled with excess or normal water treatments. Tree sapling root: shoot ratios were highest in the drought treatment, possibly as an adaptation to low water-supply. Specific leaf area was higher with warming than ambient, further elucidating the positive effect of increased temperature for tree growth. Drought has important negative implications for grass productivity, and may reduce the competitive effects of grasses on trees, particularly during the early sapling stage, when competition for resources between tree saplings and grasses are maximised. Coupled with increased performance of trees under warmer conditions, future climate change may further promote tree establishment, especially in areas where rainfall is limiting.

The Extract of Acacia sieberiana (DC.) Leaf Prevents Blood REDOX Status, Oxidative Lipid and DNA Damage Complications in DMH-induced Pre-Malignant Colon Cancer in Male Rat

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ORPHOLOGICAL VARIATIONS FOR THE TAXONOMIC IDENTIFICATION OF SOME SPECIES OF ACACIA FROM ZARIA, KADUNA STATE NIGERIA

Acacia belongs to the family fabaceae among the largest legume genera consisting of eighteen species with the majority of the species distributed in tropical and sub-tropical Africa. Classification of Acacia have remained a daunting task due to it wide spread and also hampered by is large number of species ,prevalence of morphological convergence. Morphological variations in foliar, thorn, inflorescence of some Acacia species found in Zaria for their taxonomic identification at species level were evaluated were Seven species and one variety of Acacia were taxonomically classified using morphological characters. In almost the species leaves were compound bipinnate, alternate and pinnulesare oblong. However the pinnules of A. senegal are obovate. In A. auriculiformis the leaves are simple and sickle-like in shape. Leaves texture ranges from glabrous to pubescent and leaf margin were entire in all the species. The morphological measurement parameters were analyzed using ANOVA cooperation and the results indicate variations among the species. The variations observed in some of the characters could be of taxonomic importance in the identification of the species. Overall ranking indicated that Acacia sieberiana var sieberiana and Acacia sieberiana var villosa were the best with high values of morphological characters of pinna length (3.50±0.11 cm and 3.82±0.16 cm respectively) and number of pinna (18.80±1.32 and 41.70±1.52 respectively). The high values of pinna could be used in solving taxonomic problems associated with Acacia species and in mapping out breeding strategies for the production of cultivars with better foliar yield of Acacia species in Nigeria

A comparative study of physicochemical, proximate and minerals analysis of some underutilized wild edible seeds used as condiments in Nigerian traditional soups

The present study focused on Physicochemical, proximate and mineral analysis of some underutilized wild edible seeds (Parkia biglobosa, Prosopis africanum and Acacia sieberiana) used as condiments in Nigerian traditional soup and consumed by different tribal communities across the country. The seed samples were all pulverized and their properties determined appropriately. The physicochemical properties of the three seed samples were comparable with each other and the values obtained were similar and fell within the range observed for similar seeds and powdered samples used as condiments or for industrial purposes. Swelling and solubility profiles of the seed samples were quite high and reflected the high water absorption capacity of the pulverized seeds. Proximate analysis of the seed samples revealed a high protein content especially for P. africanum and A. siberiana while P. biglobosa had a high fat and carbohydrate content. Elemental analysis of the pulverized seeds was also carried out to determine the mineral contents and it was observed that the concentration of the essential elements were within safety limits while the heavy metals were very low with lead and chromium absent in two of the samples which was an indication of little or no toxicity of the seeds. The results of the various analysis carried out on the seed samples p\shows that all the three (3) study seeds are safe for consumption. These lend credence to their use as condiments and indicates that they can be further explored for other uses in the food industry.

EVALUATION OF COFFEE GROWTH, YIELD AND QUALITY UNDER COFFEE SHADE TREES AT MECHARA ON STATION, WEST HARARGHE ZONE, ETHIOPIA

Abstract: Coffee production with shade trees is important to improve growth and quality of coffee, sustain and restore agroecology and nature based agroforestry practices. The trial was conducted at Mechara Agricultural Research Center (on station) in DaroLebu District of West Hararghe Zone, Oromia, Ethiopia. The study was intended to evaluate the influence of coffee shade trees on growth performance, yield and quality of coffee (Coffea arabica L.) under the canopy of Erytherina absinica, Cordia africana and Acacia sieberiana. The design was Randomized complete block design with three replications. The outcome had been observed a significant value at (p&lt;0.05) probability level, non- significant value at (p&gt;0.05) probability level and highly significance value at (p&lt;0.01) probability level between treatments. Statistically significant and non- significant differences were observed between shaded and unshaded as well as within shaded effect based on the given parameters. Integration of shade in coffee farming system created creditable promising in producing organic coffee. Shade utility could be confirmed as to be ecologically sustainable, economically viable and socially acceptable practice. In so doing that, the effect of Erytherina absinica, Cordia africana shade trees illustrated the highest mean value in most parameters, while the least one is under the Acacia sieberiana shade tree. So the effect of Erytherina absinica mean observed with the highest value on total bearing plants 60%, thousand seed weight 59% and yield in Quintal per hectare 47.4% greater than the least treatments’ mean value based on growth parameters. On the other hand, the effect of Erytherina absinica mean observed with the higher value on aromatic intensity 46.4%, aromatic quality 87.2%, acidity 92.4%, body 93.5%, flavors 88.6% and overall quality 88.6% than the least treatments’ mean value, and also the effect of un-shade mean observed with the higher value on astringency 68.8% and bitterness 93.5% than the least treatments’ mean value based on organoleptic parameters. The highest mean value of Erytherina absinica observed on total bearing plants 12.1, thousand seed weight 130 gram and yield in Quintal per hectare 5.7 based on growth parameters, while based on organoleptic parameters, the highest mean value observed under the effect of Erytherina absinica shade tree on aromatic intensity 4.5, aromatic quality 3.9, acidity 7.9, body 7.7, flavors 7.9 and overall quality 7.9. Therefore, based on the most treatments’ parameters, to be the best shade tree was Erythrina abyssinica followed by cordia africana. Commonly, the dynamic indication of the treatment’s means difference were indicated between shaded and unshaded rather than within shaded means variation at most treatments’ parameters.

In vitro Antitrypanosomal Activity and Phytochemical Screening of Selected Acacia Plant Species Aqueous Methanol Extract

Trypanosomiasis has been recognized as a scourge in sub-Saharan Africa for centuries and chemotherapy of the disease still remains unsatisfactory. This study is to explore an alternative source of antitrypanosomal agents from the stem bark of four Acacia species; Acacia nilotica, Acacia sieberiana, Acacia geradii and Acacia hockii. Dried stem bark of each plant was pulverized and extracted with 98% methanol by maceration. Phytochemical screening was carried out followed by in vitro testing of extracts on the motility of Trypanosoma congolense maintained in Ringer solution. Motility assessment of trypanosome was carried out after exposure with varied concentrations of the extracts for 2 hours. Thereafter, infectivity test was carried out using albino mice. Seventy-two mice, divided into twenty-four (24) groups of three animals were each inoculated with 100µl of the mixture containing the varying extract concentrations intraperitoneally. Berenil was used as standard drug control. Establishment of infection and subsequent Parasitaemiawere monitored in the animals for 60 days. The Phytochemical assay revealed the presence of anthraquinones, tannins, glycosides, cardiac glycosides and terpenes in all the extracts. Saponin was only present in Acacia nilotica and Acacia geradii. Incubation of parasites with each of the four acacia species recorded cessation in parasite motility which was concentration dependent. The highest concentration 20 mg/ml showed the highest effect within fifteen (15) minutes of incubation which was similar to the Berenil incubated control. However, lower doses (0.005 and 0.00005) mg/ml did not show difference from the non extract incubated negative control. Incubation of T. congolense with Acacia nilotica, Acacia sieberiana, Acacia geradii and Acacia hockii at 20, 10 and 1 mg/ml inhibited the ability of the parasites to establish infection in the albino mice as compared the standard control drug. The results indicate that the methanolic stem extracts of the four acacia species possess antitrypanosomal activity with potentials for the treatment of trypanosomiasis.

PERFORMANCE OF BROILERS GIVEN DIFFERENT DIETARY LEVELS OF ACACIA SIEBERIANA DC. VAR. SIEBERIANA SEEDS

The study was aimed at evaluating the seeds of a leguminous plant, Acacia sieberiana DC as an alternative source of dietary plant protein for broilers. Five experimental diets containing 0 (control), 5, 10, 15 and 20% Acacia sieberiana seeds (ASS) were formulated and fed to 5 groups of birds during starter (0 - 4 weeks), grower (5 - 8 weeks) and finisher (9-12 weeks) periods respectively. There were 3 replicates per treatment, with 10 birds per replicate. At the end of the experiment, average weekly liveweight gains of 128.90 ±24.17, 122.68±25.09, 112.79 ± 22.83, 96.40 ± 21.53 and 99.56 + 21.53g were obtained for the birds on 0, 5, 10 and 20% ASS inclusion respectively. The average weekly feed consumption values were 413.47 ± 63.63, 408.59 ± 63.82, 304.60 ± 61.70, 347.96 ± 58.0 and 352.83 ± 59.76g for the birds on 0, 5, 10, 15 and 20% ASS respectively. The feed efficiencies were 0.289 ± 0.03, 0.272± 0.03, 0.264 + 0.03, 0.248 ± 0.03 and 0.253 ± 0.03 for the birds on 0. 5. 10. 15 and 20% ASS respectively. The data revealed that in general, the birds on 0, 5 and 10% ASS inclusion performed better (PÇ&lt;.05) than birds on 15 or 20% ASS. Results of carcass evaluation show that the gizzard, lungs and heads of the control birds had significantly (PÇ&lt;.05) higher weights than those of birds on 15 and 20% ASS. From these results it can be concluded that up to 10% ASS could be incorporated into poultry diet without deleterious effect on broilers.

Water uptake plasticity of savanna trees in encroached grassland: small trees match the mature trees

Processes linked to woody plant encroachment in grassland are still not well understood, especially the interactions between trees and soil water availability. Our aim was to study the depth of water uptake by trees in grassland and its controlling factors. We studied water uptake in Vachellia sieberiana trees (hereafter called ‘acacias’) in a humid grassland of South Africa. We especially studied the effect of size classes of acacias and their position in the catena on water potential (ψ) of acacia leaves and water uptake depth of acacias across seasons, as inferred from isotope δ18O values of soil and stem water samples. Acacias were more water stressed in February (wet season) with the most negative water potentials. Taller acacias (>3 m height) were more water-stressed (ψ ± SD = −1.62 ± 0.81 MPA) than smaller acacias (<1 m height) (ψ ± SD = −1.32 ± 0.80 MPA). In September (end of dry season), all tree size classes uptake water equally in A and B soil horizons. In February (middle of the wet season), tall, medium and even small trees favoured the B horizon. Small trees had similar plasticity in water uptake to taller trees and could modify depth of water uptake between seasons. This process could increase their probability of becoming adults, and may favour tree encroachment in grasslands.