Department of Horticulture
Permanent URI for this collectionhttps://dspace.njala.edu.sl/handle/20.500.144402/161
Browse
11 results
Filters
Advanced Search
Filter by
Settings
Search Results
Item Evaluation of Tomato (Solanum lycopersicum L.) Genotypes for Horticultural Characteristics on the Upland in Southern Sierra Leone(Canadian Center of Science and Education, 2017-05-15) Kanneh, Salia MiltonNotwithstanding the importance of tomato in human diet, the average yield of the crop in Africa hardily exceeds 7.5 tha-1. There is continuous unavailability of high yielding cultivars that are adapted to diverse environment and suitable for different purposes. Consequently, evaluation of introduced tomato genotypes for desired horticultural characteristics to identify superior genotypes for additional improvement in yield and yield related traits is indispensible. Hence eight tomato (Solanum lycopersicum L.) genotypes including parental were field planted in a randomized complete block design with three replications at the Department of Horticulture Nursery Unit, School of Natural resources Management, Njala University, Njala Campus, Moyamba District, Southern Sierra Leone to evaluate them for good horticultural traits. Data collected include plant height at 50% and 100% flowering, stem girth at 50% and 100% flowering, days to first, 50% and 100% flowering, days to maturity, number of fruits set per plant, number of fruits harvested per plant, average fruit weights, fruit length, fruit diameter, fruit flesh thickness, locule number, marketable and nonmarketable fruits per plant. Results from the study indicated that all genotypes studied are adaptable to the Sierra Leone climatic conditions. P1 (097) recorded the highest number of fruits set per plant, number of fruits harvested per plant and tallest and largest plant height and stem girth at 100% flowering. BC2F2 had the highest locule number while R3P9 had the heaviest fruit weight. P2 (213) had the thickest fruit flesh thickness and longest duration to fruit maturity respectively while P1 (097), BC1F2 and R3P9 had the same number of shortest days to maturity. Regarding fruit length and diameter, R3P8 and R6P6 had the longest and widest. With respects to marketable and nonmarketable fruit per plant, P1 (097) recorded the highest correspondingly.Item Fine Monitoring of Wetlands at Provincial Large-Scale Using Object-Based Technique and Medium-Resolution Image(Institute of Electrical and Electronics Engineers, 2019-06-12) Luo, KaishengDue to extreme similarity of wetland spectra, a significant uncertainty lies in the accuracy of the traditional pixel-based classification, which is a bottleneck in the extraction of wetland information. Object-based image analysis (OBIA) has brought opportunity for fine monitoring of wetland information. However, previous studies on monitoring wetlands have focused mainly on exploratory experiments involving high-resolution images for small areas. The application of OBIA in various medium-resolution images for large areas needs further verification. Here, Landsat and China's HJ-CCD images, a new OBIA mixed binary decision tree, tasseled cap transformation, and field samples were used to refine monitoring of changes in wetlands in Hubei Province. The results showed that while the overall accuracy and Kappa coefficient of the extracted wetland information for 2000 were, respectively, 88.98% and 0.87, the overall accuracy and Kappa coefficient of the detected change were 94.75% and 89.41. This indicated that OBIA performed well with medium-resolution HJ-CCD and Landsat images in monitoring changes in wetlands at provincial scale. The area of wetlands in Hubei increased by 171.03 km2during 2000-2010. Lakes and reservoirs/ponds increased the most in the province, with respective contributions to the total wetland area of 40.21% (108.97 km2) and 59.17% (160.37 km2). At administrative unit scale, Shiyan Prefecture (157.53 km2) and Fangxian County (317.33 km2) contributed the most to the increase of wetland area. The main reason for the increase in wetland area in Hubei in 2000-2010 was the implementation of major ecological projects during that decade.Item Fungicidal effect of three plants extracts in control of four phytopathogenic fungi of tomato (Lycopersicum esculentum L.) fruit rot.(Infogain Publication, 2018) Ngegba, Patrick MaadaFungicidal effect of leaf aqueous extracts of Azadirachta indica, Tithonia diversifolia and Chromolaena odorata were determined on rot causing fungi. In the study, the phytopathogenic fungi isolated from the infected tomato fruit parts and identified based on morphological and cultural characters were: Aspergillus niger Van Tiegh, Fusarium oxysporum Schlecht, Geotrichum candidium Link and Rhizopus stolonifer Ehrenb. ex. Fr. as confirmed by pathogenicity tests. Leaf aqueous extracts of different concentrations (20, 40, 80, 60 and 100 % w/v) of A. indica, T. diversifolia and C. odorata were added to growth media prior to inoculation. All aqueous extracts of the tested plants significantly (p < 0.05) reduced mycelial growth of the fungal pathogens and this effect gradually increased with increasing concentration. Fungicidal activity was strongly exhibited by A. indica extract at 100% w/v against all the pathogenic fungi. In the case of T. diversifolia extracts inhibitiory effects at 20, 40, 60, 80 and 100% w/v were greater than those of C. odorata on A. niger , F. oxysporum and G. candidium while for R. stolonifer inhibition, C. odorata produced the highest in the all five concentrations than T. diversifolia extracts. It could be emphatically concluded that the tested plant extracts can effectively control rot causing fungi disease of tomato. This makes them potential biocide in diseases management in that they are cheap and environmentally safe as they showed fungicidal and fungitoxic ability.Item Status and types of Chiuri (Diploknema butyracea (Roxb.) H.J.Lam) owned by Indigenous Chepang Communities in Makwanpur, Nepal(2021-12-31) Chikanbanjar, RoshanChiuri (Diploknema butyracea) is a medium-sized tree that inhabits in sub-Himalayan tracks of steep slopes and cliffs at an elevation of 400 to 1400 meters from west to east of Nepal. It belongs to Sapotaceae family of plant kingdom. This study was conducted to assess status of Chiuri tree in Raksirang Rural Municipality (RRM) with particular interest to location, khoria aspect, age and types. Primary data were collected through questionnaire survey, interviews, informal discussion, etc. whereas secondary data were collected through desk review. Biometric data such as seed size and seed count per kg of seeds were measured using measuring scale and weighing balance. Four types of Chiuri namely Wayo, Lanyo, Titiya and Tomyo were found in RRM depending on ripening time of fruit. Most of them have Chiuri older than 30 years of age and their khoria facing south direction. Chiuri takes 6-10 years to start fruiting from seedling. Based on survey, Wayo and Lanyo were found in lower elevation whereas Titiya and Tomyo were found in higher elevation. The timing of fruit ripening was different but followed a pattern of types located in lower elevation fruiting earlier. However, defoliation timing was different and was not influenced by elevation.Item Chiuri (Diploknema butyracea (Roxb.) H.J. Lam): A tree species for improving livelihood of Chepang in Makwanpur, Central Nepal(University of Hawaii Press, 2021-03-23) Chikanbanjar, Roshan**Background:** Chepang, a semi-nomadic minority group, is dependent on common and private forest resources, Chiuri (Diploknema butyracea (Roxb.) H.J. Lam) to be precise, for livelihood. This study was carried out to understand the household economy of Chepang and evaluate the benefit of Chiuri and its by-products such as Chiuri butter, honey or seeds in Raksirang Rural Municipality (RRM), Makwanpur, Nepal.Methods: Primary data were collected through questionnaire surveys, interviews, informal discussions, etc. whereas the secondary data were collected through desk review.Results: Many Chepangs (41 percent) who collect Chiuri earn an average of US\$ 41.43 annually by selling Chiuri seeds, which is very low in the present market value context. People of RRM are still living under poverty with annual income of less than US\$ 414.35 per household (78 percent) and food availability for < nine months (56 percent) in a year. Many of them (55 percent) extract more than 30 kg of butter and surplus butter are sold for US\$ 1.65-2.49 per kg. Normally they produce butter for domestic uses. Butter is applied for muscle spasm.Conclusions: Our result shows that Chiuri is a natural complement to the livelihood of Chepangs. Bee farming in Chiuri growing areas helps generate additional income. Beside local economy, bee and Chiuri products are folkloric for primary healthcare. Hence, Chiuri is a plant with various economic benefits. Proper management of Chepang, Chiuri and bee is an integrated approach of biodiversity conservation.Keywords: Chepangs, Chiuri, bee farming, livelihood, collection centerItem Growth and yield response of Okra to method and time of poultry manure application under rain-fed conditions(University of Ibadan, 2022-10-18) Mornya, Philip Maada PessimaMatching nutrient demand with supply is critical for plant growth, development and yield. This study investigated the growth and yield response of Okra (Abelmoscus esculentus) to the method and time of poultry manure application, in order to match the time of optimum nutrient release with nutrient uptake by the okra plants. A randomized complete block design with 6 treatments and 3 replicates was used for this study. The poultry manure was applied at three different times: During planting (0-DOP), 2 weeks after planting (2-WAP) and 4 weeks after planting (4-WAP) using two application methods: surface-broadcasting and plow-incorporation. Results showed significant differences in method and time of application of poultry manure. The application of poultry manure, using plow-incorporation method on the day of planting (0-DOPI), significantly improved growth and yield (5.88 t ha-1) of okra. Also, 0-DOPI treatment took fewer days to attain 50% flowering (55 days) and fruit setting (58 days). This indicated that the match between nutrient demand and supply was most evident under 0-DOPI treatment. However, the surface broadcasting method at 2-WAP and 4-WAP, could not match release and supply of nutrients with critical developmental stages of okra. Hence, poultry manure incorporation at time of planting could improve okra production in the study area.Item Impact of Different Sources of Organic Fertilizer on Growth and Yield Parameters of Tomato (Solanum lycopersicum L.)(2024) Jalloh, Osman Bashir SalamThis study investigates the impact of different organic fertilizer sources on the growth, phenology, and yield parameters of tomato (Solanum lycopersicum L.) in Njala, Moyamba District, Southern Sierra Leone. The treatments included NPK 15:15:15 fertilizer, goat dung, pig dung, and poultry manure in a Randomized Complete Block Design (RCBD) with three replications. Results revealed significant differences in morphological characteristics, with poultry manure enhancing plant height (63.29 cm), stem girth (0.88 cm), leaf number (69.23 leaves), and leaf area (352.94 cm²) compared to other treatments. In terms of phenology, poultry manure also resulted in the earliest flowering (30.14 days) and fruit set (33.05 days), indicating its superior role in promoting rapid reproductive development. Moreover, yield parameters showed that poultry manure produced the highest fresh fruit number (442.21 fruits) and weight (502.04 kg/ha), outperforming goat dung (309.06 fruits; 444.55 kg/ha) and significantly surpassing pig dung (203.13 fruits; 108.69 kg/ha). NPK fertilizer demonstrated moderate effects, producing 353 fruits and 360.13 kg/ha, but did not match the performance of organic fertilizers. These findings underscore the effectiveness of organic manure, particularly poultry manure, in enhancing the growth and yield of tomato plants, suggesting its potential as a sustainable alternative to synthetic fertilizers. This study highlights the importance of integrating organic fertilizers into local agricultural practices to improve food security and promote sustainable farming in Sierra Leone. Therefore, it is recommended that vegetable farmers within Njala Community should incorporate the use of poultry manure and Goat dung at 5t/ha rate into their activities to achieve high yield potential of tomato productionItem Potential impact of climate change on drought-tolerant maize varieties and nitrogen fertilization in Nigeria savannas: a decision support tool (DST) analysis(Emerald Publishing Limited, 2025-10-20) Beah, Aloysius AlysiusPurpose Nitrogen fertilization is a crucial factor in sustainable agriculture practices because it enhances the resilience of maize crops to climate change. This study aims to quantify location-specific adaptation measures to climate change using drought-tolerant maize varieties and N fertilization in the savannas of Nigeria using the Agricultural Production Systems Simulator (APSIM) model. Design/methodology/approach The calibrated APSIM-maize module was validated using an independent dataset from field experiments conducted under different N fertilization levels within savanna agroecological zones (AEZs). The impacts of climate change were assessed under low and high emissions representative concentration pathways (RCPs), 4.5 and 8.5 W m2 scenarios, for the near-term (2010–2039) and mid-century (2040–2069). Findings The study found that the yields of early and medium maturing maize varieties decreased under climate change scenarios. For the early variety (2009EVDT), yields decline by 1–4% under RCP 4.5 and 3–8% under RCP 8.5 in the near term, and 2–12% under RCP 4.5 and 1–12% under RCP 8.5 mid-century. For the medium variety (IWDC2SYNF2), grain yield decreases were 1–5% under RCP 4.5 and 2–11% under RCP 8.5 near-term, and 1–8% under RCP 4.5 and 3–14% under RCP 8.5 mid-century. Applying N-fertilizer at 90–120 kg ha−¹ can minimize these effects across the three AEZs. Practical implications This study supports strategic nitrogen fertilization and drought-resistant maize varieties to maximize yields and ensure food security under climate change. The government and relevant agencies should strengthen policies to help farmers adopt adaptive strategies to cope with projected high temperatures and droughts, to enhance sustainability. Originality/value The originality of this paper stems from the contributions of the various authors: Conceptualization, A.B., A.Y.K. and J.M.J.; methodology, A.B., A.Y.K. and J.M.J.; validation, A.B., A.Y.K. and A.I.T.; formal analysis, A.B. and F.M.A.; field experimentation, A.B. and A.I.T.; resources, A.Y.K. and J.M.J.; data curation, A.B., A.I.T. and F.M.A.; writing original draft preparation, A.B., A.Y.K. and F.M.A.; writing review and editing, A.B., A.Y.K., J.M.J, A.I.T. and F.M.A.; supervision, A.Y.K., J.M.J. and F.M.A.; funding acquisition, A.Y.K. and J.M.J. All authors have read and agreed to the published version of the manuscript.Item Development and Reproduction of Sweet Potato Whitefly Bemisia tabaci (Homoptera; Aleyroididae) on Four Vegetable Crops in Southern Sierra Leone(Scientific Research Publishing, 2025) Musa, Peter DennisBemisia tabaci is a polyphagous herbivore that feeds on a wide range of horticultural and ornamental crops cultivated under diverse ecological zones. In Sierra Leone, B. tabaci is found to infest a wide range of vegetable crops by directly feeding on phloem sap thereby inducing physiological disorders, and also serve as a vector to gemini viruses. Invariably the destructive feeding of B. tabaci affects the productivity and aesthetic values of vegetables and other horticultural crops and hence is considered a serious economic pest. A bioassay experiment was carried out by rearing B. tabaci populations on four vegetable crops under controlled laboratory conditions to determine its life table and demographic parameters. Results showed that the intrinsic rate of growth which measures the population size and growth pattern was highest for populations reared on tomato crops with the following values: rm 0.145 female female−1 day−1, the gross reproduction rate (Ro), and finite growth rate λ were highest for population reared on tomato, correspondingly the development period from egg-adult emergence was shortest with a value of 26 d. Conversely, the computed demographical parameters rm, λ and Ro for the population reared on sweet pepper were 0.106 female female−1 day−1 respectively, with a corresponding development period egg-adult emergence as 36d. The computed biological parameters for okra and garden egg varied with intermediary values between tomato and pepper host materials. The survivorship rates were quite significant for the smaller instars (Instars 1-III) with over 80% surviving to pre-pupa and pupa stage for the populations reared for all the test materials. High mortality was noticed for the pre-pupa and pupa stages as their survival rates were significantly low compared to the high survival rates of the smaller instars. Less than 50% of pupae failed to emerge to adults except for populations reared on tomato test materials where 52% emerged to adults. The study indicated tomato as the most suitable host among the four vegetable crops. Although life table and demographic parameters are invaluable information for forecasting pest populations and help in designing pest management efforts, further investigations such as the economic threshold and economic injury levels of B. tabaci population are requisite decision tools for sound pest management decisions of B. tabaci on these vegetable crops. The information obtained from this investigation would be quite relevant for extension service and pest management practitioners where mixed vegetable farming is a common practice.Item Evaluation of the Functional Response of Seven Spotted Lady Bird Beetle Coccinella septumpunctata (Coleoptera: Coccinellidae) on Five Varying Densities of Bemisia tabaci (Homoptera: Aleyrodidae) Population under Controlled Laboratory Conditions(2026-02-12) Musa, Peter DennisBemisia tabaci is a cosmopolitan polyphagous insect undermining the productivity of a wide range of crops including but not limited to horticulture, ornamental and vegetable crops. The management of B.tabaci has been dominated by the use of broad-spectrum insecticides, though having the unique feature of reducing pest population below action threshold and economic injury level, their usage is however characterized with side effects including but not limited to environmental degradation and development of resistant genes in insects. The use of natural enemies (biological control) is considered more sustainable and viable option, environmentally friendly and poses no risk to users. Among the numerous biological control opportunities, the use of coccinellid beetles potentially proves to be quite promising and are abundantly found in insect infested vegetable fields. The ability of natural enemies as effective biological control agents is highly vested in their respond to density of preys density-dependent which can be measured in terms of their functional responses focusing on instantaneous search rates (a) and handling time (Th) as distinct and invaluable parameters. A bioassay cage experiment under laboratory conditions was carried out to evaluate the functional response of seven spotted lady bird beetle C. septumpuntata late 4th instars, male and female adults respectively on varying densities of B. tabaci eggs, 2nd and 3rd instars. The results were normalized and nature of response curves of C. septempartite on these prey densities were characterized and determined as Type II functional response. The response curves monotonically declined with increased in pest density for the 4th instars , female and male adults when fed on 2nd instar larvae with female adults showing the highest instantaneous search rate 0.54 and lowest handling time 0.19 and maximum consumption of 10.95 prey-1hr-1 strongly indicating that the female beetles showed potential attributes as ideal biological control candidate compare to the male and late 4th instar counterparts when fed on the 2nd and 3rd instars. However, when beetles were offered with B. tabaci eggs , the 4th instars demonstrated least handling time 0.73 and higher attack rate 2.57 than the female and male counterpart correspondingly showing the highest satiation threshold 32.87 prey-1hr-1.Though the beetle demonstrated promising potential as an ideal candidate based on current laboratory findings providing insight on the possibility for mass rearing and subsequent utilization in biological control programs of agricultural pests , there is however need for further investigation under greenhouse and field scenarios. Meanwhile, the prospect of C. septumpunctata as an ideal biological control candidate on B. tabaci population is discussed.