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Volume 7 Number 1 2013
CONTENTS AND ABSTRACTS
Tajudeen Adebayo Adeniji (Nigeria) Review of Cassava and Wheat Flour Composite in Bread Making: Prospects for Industrial Application (pp 1-8)
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Review: Cassava is emerging as a dominant staple of primary importance in many developing countries of the humid and sub-humid tropics in Africa and elsewhere. Nigeria is the largest producer of cassava in the world, while production has also increased over the past two decades in many African countries. This formidable production potential demands for a strategy for the development of Africa through cassava industrialisation under the auspices of New Partnership for Africa’s Development (NEPAD). This can be achieved through the emergence of many strong cassava-based industries with opportunities in commercial flour production for baking and confectioneries. The habit of eating bread has spread from the Mediterranean Basin throughout the world, thus making bread available in many urban centres in developing countries. The demand for bread (the most popular yeast-leavened product) is increasing globally. It is one of the least expensive and yet most important staple foods in the world. Flour is an important raw material in bread making. Processing of fresh cassava roots into flour improves product palatability, reduces the cyanide content of the processed products and facilitates fortification with other food products. The International Institute of Tropical Agriculture has developed several varieties of disease-resistant and high-yielding cassava. The trend in cassava production in Africa cannot be sustained without corresponding improvements in the diversification of their processing technology. The utilisation of cassava flour in bakery and confectionery products therefore requires upgrading to exploit its industrial potentials. The application of cassava flour as a partial replacement for wheat flour in bread making, biscuits, pastries, and snack foods could constitute an intervention programme in support of NEPAD and Millennium Development Goals of the United Nations initiative in achieving food security.
Maria Mbatudde, Sylvester Nyakaana (Uganda), Stefanie Ploß, Helmut Dalitz (Germany) Genetic Structure of Prunus africana Rosaceae (Hook.f.) Kalkm. in East Africa, as Inferred from Nuclear and Chloroplast DNA (pp 9-14)
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Original Research Paper: Prunus africana (Hook.f.) Kalkml., the African cherry, is an evergreen climax vegetation tree species typically reaching 25–30 m in height and occurs primarily in montane and submontane forests. In this study, the genetic structure of P. africana was analyzed using a coding chloroplast DNA region; Megakaryocyte-Associated Tyrosine Kinase Gene (MATK) and nuclear ribosomal internal transcribed spacer (nrITS) with 63 individuals in East Africa. This study detected low levels of nucleotide diversity in nrDNA (π = 0.00529) and cpDNA (0.00448), high levels of haplotype diversity in nrDNA (hT = 0.811) and low levels of haplotype diversity in cpDNA (hT = 0.242). As revealed by the results of AMOVA analysis, genetic differentiation for cpDNA (FST = 0.0275) was obviously lower than for nrDNA data (FST = 0.237) in P. africana. Gene flow among populations based on nrDNA data (Nm = 2.641) was significantly higher than that based on cpDNA (Nm = 0.82). Mantel test revealed a significant correlation between genetic and geographic distances for cpDNA (r2= 3.0 × 10-5) and nrDNA (r2= 7.0 × 10-5). Demographic history analyses based on pair-wise nucleotide sequence mismatch distributions revealed that only the Kakamega population was in mutation-drift disequilibrium. Tajima’s D neutrality test, however, revealed significant signatures of recent population expansion in only the Kakamega population; (D = –1.85646; P < 0.05). This study therefore proposes that the P. africana population in Elgon and Mabira forests should be conserved both ex situ and in situ, while the other three; Budongo, Kakamega and Monduli should be conserved in situ.
Omena Bernard Ojuederie, David Okeh Igwe, Somiame Itseme Okuofu, Benjamin Faloye (Nigeria) Assessment of Genetic Diversity in some Moringa oleifera Lam. Landraces from Western Nigeria using RAPD Markers (pp 15-20)
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Original Research Paper: Genetic diversity in 10 Moringa oleifera Lam. landraces from Western Nigeria was assessed using 10 arbitrary random amplified polymorphic DNA (RAPD) markers. A total of 595 fragments were obtained, out of which 485 (81.5%) were polymorphic. Primer OPT-5 exhibited the least percentage of polymorphism (26.8%) compared to other primers used. Primers OPB-3, OPB-6, OPH-2, OPH-5, OPH-6, OPT-3, and OPT-4 gave 100% polymorphism. The number of amplified fragments per primer ranged from 44 (OPT-2) to 123 (OPT-5) with a polymorphic information content (PIC) ranging from 0.8301 to 0.9280. Unweighted Pair Group with Mean Average (UPGMA) clustering placed the genotypes into two major groups. ‘MO2’ and ‘MO4’ showed very close relatedness from the dendrogram obtained while ‘MO10’ was genetically isolated from the other genotypes. 87% dissimilarity was revealed by the dendrogram. The high degree of polymorphism obtained suggests that RAPD is very useful for genetic diversity studies in M. oleifera.
Kehinde A. Okeleye, Sylvester O. Oikeh (Nigeria), Christopher J. Okonji (Nigeria/Kenya), Sunday G. Aderibigbe, Francis Nwilene, Olupomi Ajayi, Akeem A. Oyekanmi (Nigeria) Influence of Legume/Rice Sequence and Nitrogen on NERICA® Rice in Rainfed Upland and Lowland Ecologies of West Africa (pp 21-26)
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Original Research Paper: One major limitation in tropical agriculture is the loss of productivity of soils due to continuous cultivation. This is often due to leaching losses of nutrients, erosion or crop removal. There is need to explore improving productivity of soils by using grain legumes complemented with low-use of applied nitrogen. Modern interspecific rice hybrids called New Rice for Africa (NERICA®) are low input cultivars developed to overcome environmental stresses including low soil fertility. The productivity of these NERICA®s under legume/rice rotation and low-nitrogen (0 vs. 30 kgN ha-1) was evaluated in farmers’ fields in 2007 and 2008 in rainfed upland in Kasuwa Mangani northern Guinea savanna (10° 24′ N, 7° 42′ E) and lowland at Edozhigi, southern Guinea savanna (09° 45′ N, 06° 7′ E) ecologies in West Africa. Preceding plots of incorporated soybean and mucuna (Mucuna utilis) after harvest, gave 33% increments in rice yield over the previous control-fallow plots in the upland ecology. While, in the lowland, plots with previously incorporated grain soybean (cv. ‘TG× 1485 – 1D’) and dual-purpose cowpea (cv. ‘IT 98K–131–2’) residues gave about 0.8 Mg ha-1 greater rice yield than plots with previous mucuna or dual-purpose soybean. Although NERICA L-42® produced over 25% more tillers and panicles than the farmers’ cultivar, both cultivars had similar yield of 3.6 Mg ha-1, possibly because of the severe effects of iron- toxicity that limited their potentials. Results showed that upland NERICA® rice would perform better after soybean or mucuna rotation, and the lowland NERICA® after soybean cultivation than traditional fallow. Also, the low N at 30 kg ha-1 applied was adequate to enhance the effect of incorporated legume on rice yield.
Christopher J. Okonji, Emmanuel O. Ajayi, Kehinde A. Okeleye, Akeem A. Oyekanmi, Suleiman O. Sakariyawo (Nigeria) Correlation Analysis of Rice (Oryza sativa L.) Growth, Yield and its Yield Attributes in an Intercrop with Cassava and Melon (pp 27-31)
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Original Research Paper: A two-year study was conducted on three rice varieties (ITA 321, ITA 150 and WAB 189-B-B-HB), (Oryza sativa L.) in a rice/cassava (Manihot esculenta) intercrop of two cassava varieties (TMS 30572 and TME 1) and a rice/melon (Citrullus lanatus) intercrop at the Teaching and Research Farm of the University of Agriculture, Alabata, Abeokuta, during two consecutive growing seasons. The objective of the trial was to investigate the correlation between agronomic parameters and grain yield of rice in an intercrop using cassava varieties (non–branching (TME 1) and branching types (TMS 30572)) and melon. Positive and significant correlations were found for leaf area index at vegetative stage and panicle weight with grain yield of rice in the rice/melon intercrop (r = 0.66 and 0.78). Also, a negative correlation was found for plant height at the three stages of growth with grain yield (plant height at vegetative stage r = -0.42, at flowering stage r = -0.49 and maturity r = -0.43), as number of panicles per hill (r = -0.28), panicle length (r = -0.41) and harvest index (r = -0.5) contributed negatively to grain yield of rice in the rice/melon intercrop. For rice in the rice/cassava intercrop, a positive and highly significant correlation was found for tiller number (r = 0.85), leaf area index (r = 0.68), days to 50% flowering (r = 0.85) and number of panicles per hill (r = 0.81) with grain yield in both years. Plant height was negatively correlated with grain yield (r = -0.59) in both years.
Jules Ntamwira (DR Congo), Pieter Pypers (Kenya), Piet Van Asten (Uganda), Bernard Vanlauwe (Kenya), Ndungo Vigheri (DR Congo), Ariane Badesire (Rwanda), Pascale Lepoint (Burundi), Guy Blomme (Uganda) Effect of Banana Leaf Pruning on Banana and Bean Yield in an Intercropping System in Eastern Democratic Republic of Congo (pp 32-35)
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Original Research Paper: Banana-bean intercropping systems are used by many small-scale farmers in eastern Democratic Republic of Congo to maximize land use and intensify crop production. A study was conducted at the INERA Mulungu research station to determine the effect of banana leaf pruning on banana (Musa spp.) and bean (Phaseolus vulgaris, Fabaceae) yield. The East African highland cooking banana ‘Barhabesha’ was established in April 2007 at a spacing of 2 by 3 meters. The treatments consisted of different levels of banana leaf canopy coverage (5 leaves [5L] and all leaves [ALL]) and leguminous crop varieties (the bush bean ‘Ngwaku Ngwaku’ and the climbing bean ‘AND10’) which were planted in the banana plot. Bean yields were assessed during 4 cropping seasons (2008B, 2009A, 2009B and 2010A). Banana leaf pruning did not have a significant effect on time from planting to bunch harvest in either legume intercropping treatment. Banana leaf pruning did not have a significant effect on banana yield (32.3 and 28.6 t/ha for ALL; 32.2 and 26.3 t/ha for 5L for climbing and bush bean intercropping respectively). The average banana bunch weight was higher in the climbing bean (ALL: 19.4 / 5L: 19.4 kg) than in the bush bean intercropped plots (ALL: 17.2 / 5L: 16.1 kg). A reduction in the number of banana leaves (i.e. from all leaves to 5 leaves) enhanced bean yield for both legume types. Under the all leaves treatment, climbing bean yield (358 kg/ha) was slightly but not significantly higher than bush bean yield (335 kg/ha). However, it was significantly higher for the 5L treatment (512 kg/ha against 362 kg/ha). Results from a gross margin analysis of banana-bean intercropping and cropping season effects are also presented.
Amel Kerkeni, Mejda Daami-Remadi, Mohamed Ben Khedher (Tunisia) In Vivo Evaluation of Compost Extracts for the Control of the Potato Fusarium Wilt Caused by Fusarium oxysporum f. sp. tuberosi (pp 36-41)
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Original Research Paper: Nine compost extracts (C1, C2, C3, C4, C5, C6, C7, C8 and C9) based on animal manures were evaluated for their inhibitory effect against Fusarium oxysporum f. sp. tuberosi the causal agent of the potato (Solanum tuberosum L.) Fusarium vascular wilt. They were compared to one healthy control (non-treated and non-inoculated plants) and to an inoculated control (plants inoculated and non-treated). Fusarium wilt severity was assessed based on the Leaf Damage Index (LDI) and on plant growth parameters 90 days post-planting. Potato plants grown in a mixture of perlite and peat treated with different compost extracts and inoculated with Fusarium oxysporum f. sp. tuberosi showed a highly significant decrease in the LDI as compared to those inoculated and non-treated. Moreover, the development of the pathogen was completely suppressed by C2, C3 and C9 extracts. The presence of compost extracts in the growing medium allowed for a significant improvement in plant-growth parameters as compared to inoculated control and even to those of healthy control (non-treated and non-inoculated plants). Despite the presence of inoculum in the substrate, increase of plant growth in comparison to the inoculated control, exceeded 43% for the tuber fresh weight, 75% for the shoot fresh weight and 78% for the root dry weight. The C8 extract was usually the most efficient in increasing the plant growth and yield parameters as compared to the other extracts. This study demonstrated the usefulness of compost extracts as an effective organic fertilizers and as an efficient biological tool for plant protection.
Ahlem Harbi, Mohamed Elimem, Brahim Chermiti (Tunisia) Use of a Synthetic Kairomone to Control Frankliniella occidentalis Pergande (Thysanoptera; Thripidae) in Protected Pepper Crops in Tunisia (pp 42-47)
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Original Research Paper: Frankliniella occidentalis Pergande (1895) (Thysanoptera; Thripidae) is a harmful thrips species that may cause serious damage in pepper crop greenhouses. The aim of this study was to monitor and control this pest using blue sticky traps with and without kairomone capsules. Traps with kairomone capsules caught much more than twice as many thrips as those without, with highly significant differences throughout the study period proving thus the effectiveness of these substances to attract this pest. Monitoring thrips populations in the control greenhouse showed a continuous population increase, with high average values of adults and larvae of about 23.89 and 16.27 individuals/flower, respectively. However, in the greenhouse with traps without kairomone capsules the thrips population was the lowest. In the greenhouse where traps with kairomone capsules where installed, the thrips population was marked by variations throughout the study period; increasing to a very high value (20.41 adults and 10.77 larvae/flower) compared with the other greenhouses. Kairomone capsules attracted thrips from the outside, because when the greenhouse entries were closed, F. occidentalis populationsbegan to decrease rapidly, on blue sticky traps and in flowers, to 3.43 adults/flower and 1865.8 adults/trap on June 25th. These results demonstrate that kairomone capsules have the potential to improve trap capture of F. occidentalis in covered pepper crop.
Gbenga Akinwumi, Vincent Umeh, Isaac Olabode, Semeton Amosu, Babashola Adelaja (Nigeria) The Performance of Two Guava (Psidium guajava L.) Varieties Supplied with Organic and Inorganic Fertilizer under Tropical Conditions (pp 48-51)
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Original Research Paper: Mineral nutrition is a factor that can easily be modified for plant growth, and consequently soil can be amended to alleviate limitations of nutrient availability and/or absorption in many horticultural practices. Generally, the amendments provide soil and biological factors necessary for improved plant growth by affecting changes in plant growth and development, and particularly soil chemical composition. A trial was conducted to evaluate the performances of two varieties of guava supplied with poultry manure and inorganic fertilizers applied alone or in combination for over a period of two years. Two varieties of guava seedlings namely ‘Allhabad’ and ‘White delicious’ were transplanted to the field. Cured poultry manure and NPK15:15:15 were used as organic and inorganic fertilizer respectively at the rates of 0.28 t/ha organic fertilizer + 75 kg/ha NPK inorganic fertilizer at four application per year (F1), inorganic fertilizer at 150 kg/ha NPK at four application per year (F2), 0.56 t/ha organic fertilizer only (F3) and control (no fertilizer) F0. Result showed that a combination of organic + inorganic fertilizers performed better in terms of growth parameters assessed among the treatments in both varieties than plants supplied with full organic fertilizer (0.56t/ha poultry manure). However, ‘Allahabad’ had the highest stem girth and canopy cover while ‘White delicious’ had the tallest plants. The combined application of poultry manure and NPK fertilizer gave the best growth performance.
Mohamed Nabil Abd El-Mageed Omar, Salwa Fahmy Badr (Egypt), Jaime A. Teixeira da Silva (Japan), Gamalat Abel-Aziz Hermas, Heba Mossa Hewait (Egypt) Characterization of Plant Growth-Promoting Rhizobacteria Associated with Wheat (Triticum aestivum L.) from Saline Soil (pp 52-63)
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Original Research Paper: Plant growth-promoting rhizobacteria (PGPR) have the potential to enhance plant growth by various direct or indirect mechanisms. Eleven bacterial isolates were isolated from different salinized rhizospheric soils in which wheat (Triticum aestivum L.) cv. ‘Giza-139’ was growing, in Sahl-El-Tina, South Sinai, Egypt. These isolates, whose morphological and biochemical characteristics were studied, were screened in vitro for the production of indole-3-acetic acid (IAA), hydrogen cyanide (HCN), siderophores and Catalase (CAT). Results were compared with three reference strains (Pseudomonas fluorescens, Bacillus polymyxa and Bacillus circulans). Most (i.e., 8) of the tested isolates and all the reference strains (i.e., 3) could produce siderophores. IAA was detected in all isolates except for one isolate (HM9) and B. circulans. In addition, CAT activity was pronounced in isolate HM4, P. fluorescens and B. circulans. No CAT activity was detected in HM5, HM8 and HM11 isolates. The tested isolates and reference strains showed higher antagonistic activity against Alternaria triticina than against Fusarium graminearum and Helminthosporium sativum. All the isolates and reference strains were able to produce HCN. The tolerance of bacterial isolates and reference strains were evaluated against NaCl (the response of bacteria to different salt concentrations varied from one isolate to another), temperature (the highest growth was recorded at 30°C after 72 h incubation for HM1 and HM2 isolates and reference strains) and pH (highest growth of the different isolates and reference strains was recorded at pH 7 after 48 h incubation). The bacterial isolates were also characterized at a molecular level (SDS-PAGE and RAPD) in which 5 isolates (HM1, HM2, HM4, HM9, HM10) could be successfully differentiated from two reference strains (P. fluorescens and B. polymyxa).
Hala Abdel Wahab, Nesreen Ahmed Sabry Helal (Egypt) Evaluation of Preharvest Bioagent Applications for both Production and Biological Control of Onion and Strawberry under Natural Botrytis Infections (pp 64-69)
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Original Research Paper: Botrytis spp. is one of the most important airborne diseases for many plant hosts resulting in poor fruit quality and serious yield loss. This study was performed using different bioagent treatments under natural Botrytis infection experiments. Different varieties of strawberry and onion were sensitive to natural Botrytis infection more than tolerant varieties. Botrytis infection values were significantly different among strawberry organs, being higher in leaves than in stamens. In addition, despite Botrytis infection values not differing among different treatments in both strawberry and onion, fungicide was the least efficient treatment under natural conditions. Moreover, treatment with the bioagent yeast, Pichia anomala, showed an increase in strawberry flowers and fruits as well as in onion leaves and bulbs in the majority of plants. This study suggests that plant foliar application of microbial antagonists may be not an effective measure for controlling natural Botrytis infections but has large impacts on plant production and quality.
Chehaibi Sayed, Elouaer Mohamed Aymen, Dridi Bouthaina, Sahbej Karim (Tunisia) Effect of Mechanical Planting Density on Agronomic Performance of Organic Potato (Solanum tuberosum L.) Culture (pp 70-74)
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Original Research Paper: The demand for organic and quality agricultural product has increased in recent years, as population is increasing. Urban society is becoming concerned about organic food quality product. However, crop management options are extremely limited in organic systems, often leading to reduced yields. The objective of this study was to evaluate the effect of mechanized planting density on crop yield of organic potato (Solanum tuberosum cv. ‘Spunta’) conducted on the experimental plot of the Higher Institute of Agronomy, Chott-Mariem, Sousse, Tunisia. The experimental field was characterized by a sandy loam texture. Planting potatoes tubers was performed mechanically by a double row planter. Four planting densities were tested (19, 14.3, 16.6 and 12.5 plants/m2). Results showed that d4 density (40 cm between plants and 80 cm between lines, which implies 12.5 plants/m2) give the best growth parameters (fresh and dry weight of aerial parts, number of stems/plants and leaf area) and yield parameters (fresh and dry weight of tubers, tuber yield). In fact, d4 density (12.5 plants/m2) gives more than 3 stems per plants than others densities and 3000 cm2 leaf area. Concerning fresh and dry yield of potato aerial parts, d4 density gives respectively 320 g/plant and 29.28 g/plant. Regarding to potato caliber, d2 density (40 cm between plants and 70 cm between lines, which means 14.3 plants/m2) gives the highest percentage of larger caliber (> 55 mm). Tubers yield was higher with d4 density (15 tonnes/ha).
Abrougui Khaoula, Chehaibi Sayed, Dridi Bouthaina, Ben Mbarek Kamel (Tunisia) Influence of Mechanical Planting Depth on the Agronomic Behavior of a Potato Crop Conducted on Two Soil Types (pp 75-78)
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Original Research Paper: The effect of planting depth of the potato variety ‘Safrane’ at 8 and 15 cm was studied on two types of soil, a sandy loam and a loam clayey soil tilled with deep plowing using a moldboard plow and two tillage resumptions with a disc harrow. Planting was carried out mechanically at a density of 4.46 plants/m2. Results showed that best yields in aerial and subterranean biomass and tubers were obtained for plants cultivated at 15 cm of depth in the sandy loam soil. The final yield of tubers increased 35.2% compared to plants cultivated 8 cm deep. However, for the loam clayey soil, plants cultivated 8 cm deep presented the best results for the different studied parameters. The increase in the final yield of tubers compared to plants cultivated at 15 cm of depth was 23%.
Dalila Haouas, Monia Ben Halima-Kamel, Fethia Harzallah-Skhiri, Mohamed Habib Ben Hamouda (Tunisia) Assessment of Insecticidal Effect of Chrysanthemum sp. Essential Oils against Tribolium confusum du Val (Coleoptera, Tenebrionidae) (pp 79-82)
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Original Research Paper: As part of our vegetable heritage value we studied the insecticidal activity of essential oils extracted from four Chrysanthemum species against Tribolium confusum du Val, a stored products pest. The study of repellent activity of essential oils extracted from leaves and flowers of Chrysanthemum species against T. confusum adults show a strong repulsive effect of all species. Topical application of essential oils from Chrysanthemum coronarium L. and Chrysanthemum grandiflorum (L.) Batt. flowers on T. confusum pupae caused a significant insect mortality that attend 67 and 61%, respectively after 7 days of treatment. The malformation assessment of newly emerged adults issued from treated pupae showed that C. coronarium leaves essential oils caused the highest rate of insect malformation (10%). These results demonstrate the insecticidal activity of essential oils by pupae toxicity, by hormonal balance disruption (appearance of adored malformed) or by insect repellency. These three activities can enhance the protection of stored products against T. confusum. Nevertheless, further studies on other stored product insects are highly recommended to ensure maximum protection of agricultural products.
Sofiane Abdelhamid, Naziha Grati-Kamoun (Tunisia), Francesco P. Marra, Tiziano Caruso (Italy) Genetic Diversity of Major Olive Varieties from Southern Tunisia (pp 83-85)
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Short Communication: Considering the importance of olive-growing in Tunisia, microsatellite (SSR) analysis was used to study the genetic variation among twenty olive accessions from southern Tunisia. This set of olive microsatellites showed potential utility for genetic studies and it could contribute to the development of strategies for Tunisian germplasm conservation and breeding. Unweighted pair group method cluster analysis was performed and cultivars separated in three main groups. Five polymorphic simple sequence repeats (SSR) loci were employed and they revealed 38 alleles with a mean number of 7.6 alleles per locus. Genetic variability was wide as indicated by high values of both observed heterozygosity (mean value = 0.79) and PIC values (average value = 0.60). Cultivars formed 3 distinct and clear groups. Var. ‘Chemlali’ was grouped with the others cultivars and showed low genetic diversity. We hypothesize that this variety is a population of cultivated varieties, with the presence of different clones of the same cultivar.
Moses S. Owolabi, Wasiu Kazeem (Nigeria), Noura S. Dosoky, William N. Setzer (USA) The Leaf Essential Oil Composition of Eugenia javanica from South West Nigeria and Insecticidal Activity against Sitophilus zeamais (pp 86-88)
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Research Note: Volatile oils play an important role as natural insecticides for protection of stored food products. Members of the Myrtaceae have been used traditionally as insecticides and insect repellents. In this work we have examined the chemical composition of Eugenia javanica leaf oil, which was obtained in 0.63% yield, and the activity of the oil as a contact insecticide against the maize weevil, Sitophilus zeamais. E. javanica leaf oil was composed largely of α-terpineol (14.1%), terpinen-4-ol (7.2%), (E)-caryophyllene (6.6%), α-cadinol (12.2%), caryophyllene oxide (9.6) and 1-epi-cubenol (6.0%). The oil showed notable contact toxicity to S. zeamais (100% mortality after 96 h). The insecticidal activity of E. javanica oil is likely due to relatively high concentrations of known insecticidal components α-terpineol, terpinen-4-ol, and caryophyllene oxide, and is consistent with the traditional use of this plant family as an insecticide and insect repellant.
Christian Okechukwu Anyaoha (Nigeria) Agro-Morphological Variability of Ocimum gratissimum L. and Three Other Accessions of Basil in South-western Nigeria (pp 89-92)
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Research Note: BasilOcimum basilicum is one of the highly valued medicinal and aromatic plants that is widely used in different parts of the globe. Field evaluation of 4 basil accessions (2 indigenous and 2 exotic types), was carried out at Ibadan, Nigeria. Considerable level of genetic variation for the various traits studied was recorded. Thirteen quantitative and six qualitative traits were evaluated. Relatively high variation was recorded for plant height, number of branches, leaf length, inflorescence length, petiole length and days to 50% flowering an indication that these traits can be further improved through selection. Least variability was recorded for 1000 seed weight, number of seeds per pod, canopy cover and leaf width. Leaf length and width varied from 3.9 to 20.0 cm and 1.7 to 10.95 cm, respectively. Also, a wide range of variation was recorded for qualitative traits such as seed, stem, flower, leaf and stem colour. Absence of hairiness on the entire plant parts was observed in all the accessions. The results of this study indicated that the two local accessions (Tree and Bush basil) could be used as good parents for basil improvement programmes geared towards enhancement of leaf size based on market demand, taller plants with durable stems, better stability and adaptability to west African environments.
Maud Muchuweti, Michael Bhebhe, Batsirai Chipurura, Abisha Kasiyamhuru, Kudakwashe Chitindingu (Zimbabwe) Determination of Profiles, Antioxidant Activity and Quantity of Phenolic Compounds in BambaraNut (Vigna subterranea) Varieties Found in Zimbabwe (pp 93-98)
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Research Note: Five (fresh and dried) varieties of Vigna subterranean nuts commonly known as bambara nuts were categorized according to their skin and helium color. The nuts were separated into groups namely maroon, brown, variegated, light and dark helium and were assayed for total phenolic content, free radical scavenging, reducing power, inhibition of phospholipids peroxidation and tannin content. The highest total phenolic content was found in brown nuts with (580 mg/100 g) for fresh and (347 mg/100 g) for the dried nuts. The least total phenolic content was in dark helium nut, with (185 mg/100 g) for the fresh ones and (120 mg/100 g) for the dried. The vanillin HCl assay was found to be more sensitive as it gave much higher tannin content than the butanol-HCl assay. In the vanillin HCl, highest tannin content was in the brown nut, with (1.7 g/100 g) for fresh and (1.12 g/100 g) for dry and the least in dark helium with (0.46 g/100 g) for fresh and (0.06 g/100 g) for dried nuts. Butanol-HCl values were much lower than those for vanillin-HCl, with brown nut recording the highest tannin content of (0.0058 g/100 g). Free radical scavenging activity was tested using DPPH assay. Fresh nuts exhibited a higher radical scavenging potential than the dried nuts with the brown and maroon being the most powerful scavengers. Only dried nuts were assayed for reducing power, inhibition of phospholipids peroxidation which the results were positive.
Jaime A. Teixeira da Silva (Japan), Bouzid Nasraoui (Tunisia) International Collaboration, Partnerships or Co-operation (CPC) in Science Writing: Case of Africa and the Middle East with a Focus on Tunisia (pp 99-105)
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Opinion Paper: Africa and the Middle East are currently the center of socio-political focus, due to unrest and instability, and whether we are from Beijing, or from Brasília, the events in these broad geographic locations affect us as citizens of the world, and, as a subset, as scientists. For most of the countries in the northern belt of Africa and the Middle-East, except where there has been an Anglo-Saxon vestigial linguistic influence, do not use English as a first language. This places scientists from countries in these regions in a clearly disadvantaged situation (through explicit or implicit bias) when attempting to publish in high level journals, mainly published by Western developed countries. Most of the scientists from these countries face serious difficulties related to language and scientific writing skills during the preparation of scientific manuscripts. This difficulty is now currently being severely compounded by a global economic recession and extreme, often violent, socio-political events that deeply disturb the effective (due to lack of resources, stability, psychological welfare) focus on science. Within this extremely complex setting, we bring you viewpoints that attempt to show the links between these socio-political events, and between current and past academic structures, that foment further instability in science, or to stabilize through the implementation of novel good means. Although the socio-political prospects of the mid-term future look probably uncertain, we are confident that there may be pockets of strengthening scientific ties that would allow for the betterment, not only of science, but of society, through a scientific-based understanding of cross-cultural differences encompassing race, gender, and religion.
Oyeboade Adebayo (Nigeria) Science Research and Publication in Africa: The Nigeria Perspective (pp 106-109)
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Opinion Paper: Africa is a continent of huge ethnic and cultural diversity. This often led to political instability, poverty and disease prevalence. Science and technology is crucial to the continent’s economic prosperity, food security, disease control and environmental sustainability. The wise use of this tool and its visible output in terms of scientific collaboration and publication is still lacking in Nigeria. In this opinion paper I wish to highlight factors affecting the development of science research and publication in Nigeria vis a vis the continent and global picture. This information could further sharpen the focus of policy makers to evolve strategies to access faster the gains and developmental impact of science and technology research on the country’s economy.
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