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Volume 2 Number 1 & 2 2008 
CONTENTS AND ABSTRACTS
Number 1
Oluwole O. G. Amusan (Swaziland) Ethical and Environmental Issues in Bioprospecting for Drugs through Traditional Medicine: The Case for Swaziland (pp 1-9)
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Invited Mini-Review: Traditional medicine is very popular in Swaziland as in many other developing countries. Plant materials constitute the main components of the medicine. There is a great pressure on the flora because of the unsustainable exploitation of the bioresources through herbal medicine. Many of the drugs used in orthodox medicine have their origin from plants and a large percentage of these phytomedicines were developed with lead from traditional medicine. The prospect of further development through this route is very high. However, there are some ethical issues inherent in traditional medicine and the search for drugs through the ethnomedical route. Apart from the destruction of bioresources, there are some pertinent ethical issues which should be addressed: Traditional Medical Practitioners (TMPs) have no empirical data to substantiate their claim for efficacy and safety of their products, therefore, the sanctity of life is compromised; in some countries, for example Swaziland, there is no regulating body controlling traditional medicine; in many instances a single traditional remedy is claimed to cure many unrelated diseases; morbidity arising from the use of herbal medicine is unknown; bioprospecting through soliciting information from the TMPs amounts to endorsing the use of humans as guinea pigs for experimentation which is unethical, to say the least; rituals and magical practices which may involve the use of human parts and the exploitation of custodians of indigenous knowledge by those employing indigenous knowledge for economic benefit. This review discusses how these pertinent issues could be addressed through legislation and collaborative efforts of all stakeholders.
Munang Tingem, Mike Rivington (UK), Gianni Bellocchi (Italy), Sayed Azam-Ali, Jeremy Colls (UK) Comparative Assessment of Crop Cultivar and Sowing Dates as Adaptation Choice for Crop Production in Response to Climate Change in Cameroon (pp 10-17)
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Original Research Paper: The Cameroon’s agricultural sector is potentially vulnerable to climate change and adaptation policies may be able to mitigate some of this vulnerability. This paper investigates some adaptation options within the context of Cameroon’s food production. A methodology is applied where two atmosphere-ocean general circulation models (GISS and HadCM3), are coupled to a cropping system simulation model to simulate current and future (2020, 2080) crop yields for selected key crops (bambara, groundnut, maize, sorghum, and soybean) in eight agricultural regions of Cameroon. For the future, substantial yield increases are estimated for bambara, soybean and groundnut, while little or no change or even decreases for maize and sorghum yields, varying according to the climate scenario and the agricultural region investigated. We explored the advantages of specific adaptation strategies specifically for three crops viz. maize, sorghum and bambara groundnut, using GISS scenarios only. Changing sowing dates may be ineffective in counteracting adverse climatic effects because of the narrow rainfall window that strictly determines the timing of farm operations. In contrast, later maturing new cultivars could be extremely effective in offsetting adverse impacts, giving the highest increases in productivity under different scenario projections without management changes. Under one climate change scenario a 14.6% reduction in maize yield was converted to a 32.1% increase; a 39.9% decrease in sorghum yield was converted to a 17.6% increase. For bambara groundnut, yields were almost trebled (37.1% increase above that for sowing date alone (12.9%)) due to increase length of growing period and the positive effects of higher CO2 concentrations. The results provide useful guidance and motivation to public authorities and development agencies interested in food security issues in Cameroon and elsewhere.
Dalila Haouas, Fethia Harzallah-Skhiri, Monia Ben Halima-Kamel, Mohamed Habib Ben Hamouda (Tunisia) Three Chrysanthemum Flowerhead Powders in Controlling Feeding and Behaviour of Spodoptera littoralis (Lepidoptera:Noctuidae)(Boisduval) (pp 18-22)
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Original Research Paper: Powders prepared from Chrysanthemum coronarium, C. myconis and C. segetum (Asteraceae) were tested for their effectiveness on Spodoptera littoralis larval feeding behaviour, development and survival under laboratory conditions. The powders were incorporated into an artificial diet at three concentrations (4, 8, 16% w/w), and tested in a no-choice bioassay. Third-instar larvae were individually fed on an artificial diet added with powders of the three Chrysanthemum species for 10 days. Each diet disc was weighed before presenting it to the larvae, and reweighed and replaced by a newly weighed disc every 2 days throughout the trial. Each larva was also weighed every 2 days. Consumption of control and treated discs was recorded and antifeedant indices and relative growth rates (RGR) were calculated. Duration of stages, mortality and deformities were also recorded until adult emergence. A 10-days feeding period promoted the prolongation of larval instars, a potent antifeedant activity, reduction in the RGR, a moulting disruption and mortality of S. littoralis in a dose-dependant manner. When higher concentrations of flowerhead powders were applied the effects appeared shortly and mortality was higher especially when larvae were fed 16% of C. myconis powder, and a less effect was observed with C. coronarium. Chrysanthemum powders may contain secondary compounds with insecticidal activities causing mortality and disrupting the development of larvae and thus preventing them from causing damage to the crop.
Naïma Boughalleb, Mounira Souli, Hamida Ouled Sghaier (Tunisia) Occurrence and Geographic Distribution of Wheat Fusarium Head Blight and Fusarium Root Rot in Jendouba’s Areas of Tunisia (pp 23-26)
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Short Communication: Mycological analysis of infested wheat plants (Triticum durum L.) collected from 68 fields in the low valley of Medjerda (Bousselem, Brahim, Bir lakhther, Souk essebet, Jendouba Northern, Oued Meliz and Ghardimaou) was performed in 2006. Eight hundred and fifty three isolates were obtained from the feet and root; 1580 isolates were identified from the head. On the collar, we identified Fusarium solani (52.5%), F. culmorum (27%), F. graminearum (11%) and F. oxysporum (9.5%). These species were present in all prospected areas except for F. graminearum which was not found in Bousselem. As for head blight, in addition of these four species which were isolated at a 28, 13, 16 and 30% frequency, respectively, we detected F. equiseti (9%) in Oued Mliz and F. poae (4%) with an important frequency in Souk Essebet area. The technique adopted to efficiently isolate Fusarium species was very satisfactory. Our study shows a frequent co-occurrence in single fields of several species of Fusarium.
Hajer Regaieg, Najet Horrigue-Raouani (Tunisia) Biological Characteristics of Two Populations of Meloidogyne spp. Virulent to the Mi Resistance Gene in Tomato Isolated from South Tunisia (pp 27-29)
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Original Research Paper: Two populations of the root knot nematode were analysed for their virulence against the single dominant gene Mi which controls resistance in commercially grown tomatoes. These populations were obtained from resistant tomato roots in a naturally infested plastics house at two locations in south Tunisia, Gabes and Kebilli. Identification of Meloidogyne species by morphological identification and izozyme electrophoresis showed the presence of two species, M. javanica and M. incognita at a 25%:75% ratio. Several resistant and susceptible tomato cultivars were used. The two populations were able to develop and to reproduce similarly on resistant and susceptible cultivars. The development rate (Pf/Pi) was generally greater on tomato genotypes heterozygous for the Mi gene than on homozygous genotypes.
Adamu Usman Izge, Dauda Philip Alimta (Nigeria) Comparative Performance of Masakwa Sorghum and other Sorghum Cultivars under Rainfall Conditions (pp 30-33)
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Original Research Paper: A field experiment was carried out in Maiduguri in the semi-arid region of North eastern Nigeria during the 2007 cropping season. The aim of the experiment was to compare the performance of some sorghum cultivars (‘Masakwa’, ‘BOSADP’, ‘Kilburi’, ‘Chakalare white’, ‘Chakalare brown’, ‘Jigari’ and ‘Kafimoro’) under rainfall conditions. Treatments were laid out in a randomized complete block design (RCBD) with three replications each. Significant difference existed among the cultivars with respect to most of their quantitative traits evaluated. ‘Chakalare white’ and ‘Chakalare brown’ resulted in the highest grain yield, although they matured late. ‘Masakwa’ yield the least and also matured late. However, cultivars ‘BOSADP’ and ‘Jigari’ matured early and resulted in relatively higher grain yields even though not as high as ‘Chakalare brown and Chakalare white’. Our study indicates that ‘Masakwa’ sorghum, which is predominantly grown only during dry periods under residual moisture on vertisols can in fact be grown on sandy soils under rainfall conditions. This is a preliminary study and a continuous and broader evaluation will be undertaken before a particular breeding strategy is undertaken.
Mejda Daami-Remadi, Samia Zammouri, Mohamed El Mahjoub (Tunisia) Effect of the Level of Seed Tuber Infection by Rhizoctonia solani at Planting on Potato Growth and Disease Severity (pp 34-38)
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Original Research Paper: The effect of different levels of seed tuber infection by Rhizoctonia solani sclerotia at planting was assessed on the severity of stem canker and black scurf and on the growth and yield of potato (Solanum tuberosum) plants cv. ‘Spunta’. Collar necrosis and tuber infection by R. solani, observed four weeks after planting, increased with the level of seed tuber infection by the pathogen. In fact, plants that developed from tubers with a 4 to 5 severity index at planting showed the presence of large stem cankers and a high incidence of black scurf. The vigour of the affected plants, estimated by the fresh and dry weights of the aerial and the subterranean plant parts, was negatively proportional to the level of tuber infection. Furthermore, the most important losses in the mean fresh tuber weights, depending of the level of seed tuber infection, reached 60% for plants forming from tuber with the highest level of infection. This study showed the role of initial seed tuber infection on disease development, severity and expected impact on yield.
Number 2
Alexander K. Anning, Nada T. Grant (Ghana) An Evaluation of Local Community Participation in Forest Resources Conservation in some Selected Districts of Ghana (pp 39-45)
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Original Research Paper: Participatory forestry management is essential for conservation, and various forestry sector reforms in Ghana have advocated for its adoption, yet conservation policies in the country have largely been formulated and implemented with profound disregard for the local communities. The effectiveness of the few reported cases of integration in some parts of the country have yet to be assessed. This study evaluated the strategy in some local communities within selected districts (Atwima, Offinso and Ejisu-Juaben) of the Ashanti region, Ghana by identifying, through a questionnaire survey, the areas and depth of involvement, capacity building and problems confronting the programme. A total of 300 locals, randomly selected, were involved in the survey. The impacts of the strategy on the health of forest reserves within the districts were assessed through field surveys. The study revealed that the local communities who were mostly farmers shallowly participated in forest management mainly by reporting illegalities (55.7%), preventing bushfires (20.3%), clearing forest boundaries (10.7%), planting seedlings (5.0%) and employment as forest guards (2.7%). In terms of capacity building, only 23% of the respondents had received training in bushfire prevention and 21% on the taungya agriculture system, demonstrating the lack of commitment on the part of the official forest managers towards deep integration. Major problems confronting the strategy included lack of logistics, interest, threats and incentives. The Asenanyo Reserve (H1 = 3.445; E = 0.881) in the Atwima district was healthier than the Asufo Reserve (H1 = 1.949; E = 0.491) in the Offinso district which was dominated by the highly ranked invader, Broussonetia papyrifera (62.7%), suggesting a much successful participatory conservation in the former than the latter. These findings generally indicate the existence of limited and ineffective collaboration between local communities and the Forest Service Division which must be deepened if sustainable conservation of the country’s forest resources are to be achieved.
Nancy M. Muthoka, Paul D. N. Kiuru, Jesca Mbaka, Antony N. Nyaga, Samuel J. N. Muriuki, Charles N. Waturu (Kenya) Macadamia Nut Production and Research in Kenya (pp 46-48)
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Original Research Paper: Invited Mini-Review: Macadamia nut is an important high value export market cash crop and is mostly produced in Central, Eastern, Rift Valley and Coast Provinces in Kenya. The national average yield is 28%, 16% exportable nut and 12% for local markets. In 2008 the area under macadamia was well above 2000 ha, producing 13,510 Mt with an estimated value of $4,887,194 (Ksh 351,878,000 (1 Ksh = 0.72 US$)). Macadamia tetraphylla (rough shelled macadamia) was first introduced from Australia in 1946 forming the nucleus mother tree material for Kenya’s macadamia industry; macadamia is produced as a complimentary cash crop to coffee. Promising clones of M. integrifolia and hybrids selected for observation and evaluation resulted in the development of macadamia clones that have improved nut yields from the original 5-10 kg/tree/year to up to between 50-80 kg/tree/year, depending on the clone. Studies have been done on various crop husbandry practices that provided recommendations on spacing, propagation techniques and pest and disease management. The productivity in the 1980s was 3.4 Mt/ha, in the 1990s 3.5 Mt/ha and from 2000 it has risen to 5.3 Mt/ha. Nut production in the country has showed growth that has been triggered by competition and provision of integrated services to the farmers. The government is putting in place an appropriate policy, institutional and legal framework to sustain this growth and provide the right environment for nut production and marketing by farmers.
George Ouma (Kenya) Challenges and Approaches to Sustainable Citrus Production in Kenya (pp 49-51)
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Original Research Paper: Research Note: Agriculture is the main stay of Kenya’s economy. It contributes immensely to employment creation, foreign exchange earnings and incomes for the local population. Horticulture is its fastest growing sub-sector in terms of area of production, export earnings and employment creation. Fruits and vegetables are the main enterprises produced by the horticultural industry. Land mass in Kenya is mainly arid and semi arid and only a small part of it is used for arable farming. Horticultural production in Kenya is mainly carried out by small-scale producers. Because of the scarcity of productive land for growing horticultural crops there is need for intensive production using inputs such as fertilizers, pesticides, irrigation, etc. Fruit production is becoming very important in Kenya for domestic consumption and export. There are many constraints which limit citrus production in Kenya, citrus being an important fruit for domestic consumption. This paper discusses the constraints limiting citrus production in Kenya and the approaches to be applied to ensure sustainable citrus production and increase the area under citrus trees.
Shawky Bekheet, Hussein Taha, Usama Aly, Mohamed Matter (Egypt) In Vitro Regeneration and Molecular Characterization of Sugar Beet (pp 52-56)
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Original Research Paper: Original Research Paper: A successful protocol for the in vitro regeneration of sugar beet was established. Leaf and shoot base explants excised from in vitro germinated seedlings of sugar beet (Beta vulgaris) were cultured on Murashige and Skoog (MS) medium supplemented with different concentrations and combinations of auxin and cytokinin. Shoot base explants showed higher percentage of direct organogenesis (93%) when cultured on MS medium supplemented with 0.5 mg/l of 6-benzyladenine (BA) and 0.5 mg/l of 1-naphtaleneacetic acid (NAA) than leaf explants cultured on MS medium containing 0.5 mg/l of 6-furfurylaminopurine (kin) and 0.5 mg/l of 2,4 dicholorophenoxyacetic acid) (2,4-D) , which showed more efficient indirect regeneration (80%). Although maximum shoot proliferation was observed with MS medium containing 1 mg/l BA and 50 mg/l adenine sulfate (AS), shoot length reached 4 cm with MS medium containing 1 mg/l kin and 50 mg/l AS. Regenerated shoots rooted on indole-3-butyric acid (IBA) at 2 mg/l that seemed more effective than indole-3-acetic acid (IAA) and NAA in root formation. Protein pattern (SDS-PAGE) evidenced no variations between sugar beet cultures proliferated directly and indirectly. RAPD analysis was carried out to identify the differences amongst in vitro regenerated plantlets. PCR analysis showed slight differences between in vitro and in vivo sugar beet plantlets. Acclimatization was achieved by transferring the obtained plantlets to a mixture of peat-moss and vermiculite (1:1) under high humidity conditions.
Mejda Daami-Remadi, Samia Zammouri, Mohamed El Mahjoub (Tunisia) Relative Susceptibility of Nine Potato (Solanum tuberosum L.) Cultivars to Artificial and Natural Infection by Rhizoctonia solani as Measured by Stem Canker Severity, Black Scurf and Plant Growth (pp 57-66)
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Original Research Paper: Original Research Paper: The relative susceptibility of nine potato cultivars against Rhizoctonia solani was tested via natural seed tuber infection and artificial culture substrate inoculation. The assessment was based on stem canker and black scurf severity and negative effect on plant growth and expected impact on yield. In both experiments, symptoms of Rhizoctonia stem canker were observed on all inoculated and naturally infested plants compared to non-infested controls. Furthermore, cultivars tested showed a variable reaction to R. solani, expressed by varying degrees of stem canker and black scurf severity and subsequent plant growth, but no totally immune cultivars were found. Under either artificial or natural infection by R. solani, cvs. ‘Spunta’, and to a lesser degree ‘Elodie’, were shown to be the most susceptible to this pathogen whereas cvs. ‘Alaska’ and ‘Daisy’ were the most tolerant. However, although its higher susceptibility to Rhizoctonia disease and reduced growth compared to other cultivars tested, cv. ‘Spunta’ showed the highest progeny tuber weight but with a pronounced incidence of black scurf.
Dridi Najla, Boughalleb Naïma, Mohamed Sghaier Romdhani (Tunisia) In Vitro and in Situ Evaluation of Bio-Fungicides and Compost Tea for Biocontrol of Potato Mildew (pp 67-71)
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Original Research Paper: Original Research Paper: Potato (Solanum tuberosum) is cultivated all over the world under different climatic conditions and is susceptible to several pathogenic fungi. The most prejudicial one is Phytophthora infestans, causal agent of mildew. In this study, we used three commercial (Pre-vam®, Bio-folarTM and Bordeaux mixtureTM) and a non-commercial (compost tea) bio-fungicides for biological control of this disease. Bordeaux mixtureTM was the most efficient with a percentage of foliar destruction in the field of 26% while in vitro this product inhibited P. infestans hyphal growth on culture Rey-medium (Secale cereale L.). Pre-vam® appeared also to be effective in the field (30% of the foliar destruction) and in vitro, the diameter of hyphal growth being only 1.49 cm. However, other products were moderately efficient with a percentage of foliar destruction varying from 55 (Bio-folarTM) to 57% (compost tea).
Hortense A. Diallo (Ivory Coast), Edwin J. Anderson, Rose C. Gergerich (USA) Mixed Infections with Stunt-Associated Isolates of Blackeye cowpea mosaic virus from Arkansas and Georgia and Non-Stunt-Associated Isolates of Cucumber mosaic virus Cause Cowpea Stunt Disease (pp 72-76)
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Original Research Paper: Original Research Paper: ‘Coronet’ cowpea (Vigna unguiculata (L.) Walp. subsp. unguiculata) plants mixedly infected with cowpea stunt-associated isolates of Blackeye cowpea mosaic virus (BlCMV) from Arkansas and Georgia (BlCMVAR and BlCMVGA, respectively), and Cucumber mosaic virus (CMV) isolates that have not previously been associated with the disease in the field, resulted in plants displaying symptoms similar to cowpea stunt disease. Fresh weight analysis showed that all four combinations of mixed infections had similar effects on infected plants. Whereas in the trifoliolate leaves there was no difference in BlCMVAR and BlCMVGA accumulations in single versus mixed infections, in the stem there was a difference and that difference was significant. Although CMV strain VE 111 (originally isolated from bean in Iran, provided by Dr. Palukaitis) and CMV strain LeJ (originally isolated from bean in Japan, provided by Dr. Palukaitis) accumulations increased in the mixed compared to the single infections in the stems, in the trifoliolate leaves, CMV strain VE 111 accumulation was higher in the mixed infection while CMV strain LeJ accumulation was not. All these results not only suggest a specific interaction between CMV and BlCMV isolates in the cowpea stunt disease which varies with the plant part tested, but also show that symptom severity in cowpea stunt disease is not always positively correlated with increased CMV accumulation.
Ibrahim Y. Dugje, Stephen Naye, Isaac Z. Natawa (Nigeria) Effects of Nitrogen Levels on Striga Infestation and Grain Yield of Extra-early Maize (Zea mays L.) in a Nigerian Northern Guinea Savanna (pp 77-80)
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Original Research Paper: Original Research Paper: Low soil N and Striga hermonthica parasitism limit maize production in the northern Guinea savanna Zone of Nigeria. Field experiments were conducted during 2005 and 2006 rainy seasons to determine the influence of N fertilization on Striga infestation and grain yield of an extra-early maize variety (95 TZEE-W). The site was naturally infested with S. hermonthica due to sorghum seed multiplication at the site over the years. A randomized complete block design (RCBD) was used with 4 nitrogen levels: 0, 30, 60 and 90 kg ha-1, replicated 4 times. The maize variety 95 TZEE-W was sown at 75 × 50 cm with two plants per stand. The N status of the soil was moderate, but organic matter content and basic cations ranged from moderate to very low. Increase in N levels increased plant height, number of leaves plant-1, leaf area, leaf area index, cob weight and grain yield ha-1, while Striga counts ha-1 were reduced by the application of 60 and 90kg N ha-1. Striga count ha-1 was higher in 2005, which recorded lower rainfall than in 2006, while the photosynthetic parameters and grain yield ha-1 were higher in 2006 than in 2005. Grain yield ha-1 was positively correlated with plant height, number of leaves, leaf area, leaf area index, and cob weight, and negatively correlated with Striga count ha-1. Striga count ha-1 was also negatively correlated with plant height and the leaf parameters. Although the N status of the soil was moderate, application of 60 and 90 kg N ha-1 suppressed Striga emergence, increased the photosynthetic parameters, and increased grain yield of maize. However, increasing the N level beyond 90 kg N ha-1 may further reduce Striga infestation and increase grain yield beyond the 5.4 tons ha-1 realized in the present study.
Samuel Adelani Babarinde, Olayinka Samuel Olabode, Mathew Oladejo Akanbi, Olubunmi Adeola Adeniran (Nigeria) Potential of Tithonia diversifolia with Pirimiphos-methyl in Control of Sitophilus zeamais (Coleoptera: Curculionidae) (pp 81-86)
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Original Research Paper: Original Research Paper: The toxicity of Tithonia diversifolia leaf powderapplied at 1.0 g and pirimiphos-methyl dust (PPD) at 0.025 g (recommended dose) separately and mixing 0.5 g T. diversifolia with half, a quarter or an eighth of the recommended dose of PPD per 50 g maize grains againstSitophilus zeamais (maize weevil) was studied in the laboratory. Test parameters included mortality of adults, weight loss of grains, F1 adult emergence and persistence of the treatments. All treatments caused significant mortality compared to the untreated control. At 7 days after treatment (DAT), 90.0% mortality observed in the recommended dose of PPD was not significantly different from 83.6% mortality observed in half the recommended dose + 0.5 g T. diversifolia leaf powder. Grain weight loss followed the same pattern as mortality at 7 DAT. Only the recommended dose of PPD retained absolute potential after 30 days storage of maize grains. The mixtures retained some activity but their efficacy in storage was reduced over time. Our study reveals the potential of mixing botanicals with reduced rates of synthetic insecticides in management of stored product pests.
Ahmed Mansour, Omayma M. Ismail, Solliman M. Mohei EL-Din (Egypt) Diversity Assessment among Mango (Mangifera indica L.) Cultivars in Egypt using ISSR and Three-Primer Based RAPD Fingerprints (pp 87-92)
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Original Research Paper: Original Research Paper: Mangoes are an important fruit crop in Egypt and all over the world. Statistics provided by the Egyptian Ministry of Agriculture and Land Reclamation indicate that a total of 151,000 Fadden (equiv. 63419.310.464 ha) are planted with mango trees, with a total production of 0.596 million t in Egypt alone. The average yield per Fadden is usually about 5.41 t. For improving the yield and yield attributes, varieties are often produced and evaluated under different conditions. Utilization of molecular marker analysis provided new insights to breeders for molecular assisted selection (MAS). Depending on the marker system used, the genetic similarity analyses varied dramatically. In this report, genomic variation within twelve mango cultivars, widely used in fresh market mango production in Egypt, were investigated using two different molecular marker systems; RAPD (random amplified polymorphic DNA) and ISSR (inter-simple sequence repeat). A new strategy was used to increase RAPD potential in genetic diversity by using three different primer combinations per reaction. Different dendrograms constructed for the RAPD and ISSR results individually and collectively revealed that similarity and clustering is very dependant on the marker system used.
Christian Ugwu Agbo, Ignatius Ugwudike Obi (Nigeria) Phenotypic Variation in Reproductive Traits of Forty Six Clones of Gongronema latifolia Benth. from Southeastern Nigeria (pp 93-102)
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Original Research Paper: Original Research Paper: This study was carried out to identify phenotypic variations in the reproductive traits of forty six clones of Gongronema latifolia obtained from different localities in southeastern Nigeria. Significant phenotypic variations were observed in the reproductive traits of the species. Clones obtained from close habitats showed distinct variation in the expression of their reproductive characters. For example, EBS 015 and EBS 016 were collected from Ebonyi State and they were directly opposite each other with respect to floral traits and seed fill capability of the follicles. Days to flowering in the species was observed as the most important discriminating trait as it influenced the quantity and quality of seeds produced by clones in a follicle. Clones ENS 001, ENS 008, EBS 015 and IMS 020, which initiated flowering earlier, had a higher number of filled seeds in their follicles and a higher seed weight. Clones IMS 025 and IMS 026 flowered early and also retained highest number of filled follicles for the two years of follicle harvest. On the contrary, clones ABS 043, ABS 042 and ABS 041 had longer days to flowering and retained only one or two filled follicle(s) per inflorescence for the same period. Three floret colors that have not been reported in literature including yellowish green, all yellow and purple were identified in the species. Our data clearly supports that G. latifolia could be differentiated into different genetic subspecies based on reproductive traits of flower color, flowering habit (early or late), seed filling and seed weight and that these are reproductive traits of interest to a breeder.
George Ouma (Kenya) Effects of Forcing Method and Root Pruning on the Growth of Budded ‘Rough Lemon’ Rootstock Seedlings (pp 103-106)
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Original Research Paper: Original Research Paper: Experiments were conducted in 2004 and 2005 at Maseno University, Kenya to investigate the effect of bud forcing method and root pruning on the growth of ‘rough lemon’ (Citrus sinensis L.) rootstocks budded on ‘Washington Navel’ citrus growing on polythene pots in a polythene-covered greenhouse. The treatments comprised three bud forcing methods: bending, looping, and cutting-off and root pruning on the growth of 8-month old seedlings. The cutting off method was superior to bending and lopping since it increased the dry weights of whole plants, stem, roots, scion leaves, shoot and scion length. Forcing method did not affect the root: shoot ratio or the interaction between forcing method and root pruning. Root pruning did not significantly (P ≤ 0.05) affect whole plant dry weight but reduced scion leaves, stem and root. Both forcing method and root pruning reduced the dry weights of stem, scion leaves, stem, shoot and root and scion length. Thus, it can be concluded that the cutting-off method is superior to bending and lopping and that the forcing method is influenced by root pruning in affecting budded citrus growth.
Olamide A. Falusi (Nigeria) Inheritance of Stem Pigmentation in Two Local Varieties of Hibiscus sabdariffa in Nigeria (pp 107-108)
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Original Research Paper: Research Note: Character difference was studied in intra-specific crosses involving two local varieties of Hibiscus sabdariffa L. One variety has green pigment on the stem and calyces while the other has red. Results showed that the inheritance of red pigmentation was controlled by one independently assorting gene with a dominant allele (R-) producing red pigment on the stem and calyces. Only the genotypes (rr) homozygous for the recessive allele produced a green stem and calyces. The implications of these findings on the species evolution are discussed.
Luke N. Ukiwe, Emeka Oguzie, Chukwuemeka Ajaero (Nigeria) Adsorptive Property, Ash Content Analysis of Activated Carbon Derived from Three Nigerian Plants: Water Hyacinth (Eichhornia crassipes), Iroko (Chloraphora excelsa) and Gmelina (Gmelina arborea) (pp 109-111)
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Original Research Paper: Original Research Paper: The adsorption property and ash content of activated carbon (AC; equivalent to activated charcoal) derived from water hyacinth (Eichhornia crassipes), iroko (Chloraphora excelsa), and gmelina (Gmelina arborea) were studied. AC prepared from water hyacinth resulted in the highest percentage of decolorisation (58%), gmelina (31%) while that prepared from iroko resulted in the lowest percentage (10%) at 360 nm using the UV/visible spectrophotometry. Overall, from 360 nm to 460 nm at 20 nm intervals, water hyacinth AC produced the highest percentage of decolorisation followed by gmelina AC, then iroko AC. Total ash content analysis indicated that water hyacinth AC was highly adulterated and impure (3.53 mg/L), followed by gmelina AC (2.68 mg/L) while that from iroko (1.82 mg/L) was the least adulterated with a lower degree of impurities.
Luke N. Ukiwe, Christopher I. A. Nwoko, Conrad K. Enenebeaku (Nigeria) Intrinsic Role of pH Variables on the Sorption of Heavy Metals by Water Hyacinth (Eicchornia crassipes) on The Niger Delta Rivers, Nigeria (pp 112-114)
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Original Research Paper: Original Research Paper: The uptake of heavy metals (Cu, Ni, Cr, Co, Cd and Pb) at various pH levels (2.0, 3.0, 4.0, 5.0, 6.0) was studied at sample locations (Onitsha, Atani, Aboh and Bomadi) on the Niger Delta waterways. Results of analysis of digested samples analyzed using Atomic Absorption Spectrophotometry showed that chromium was detected at the highest concentration for all locations (Onitsha 4.220 mg/l, Atani 4.410 mg/l, Aboh 4.144 mg/l, Bomadi 3.198 mg/l) with sorption at pH 6.0 while cobalt was found in lowest concentration for all locations (Onitsha 0.002 mg/l, Atani 0.002 mg/l, Aboh 0.001 mg/l and Bomadi 0.001 mg/l) sorption at pH 2.0. Sorption of heavy metals was highest at pH 6.0 while at pH 2.0 the concentrations of metals absorbed was lowest. The accumulation of lead, nickel, and cadmium in water hyacinth was poor for all pH levels tested. |
