Rev. Dr. Prince Emmanuel Norman

Coming Soon

RESEARCH AND PUBLICATION

​(a) Research article and review publications

(1) Saquee, F.S., Diakite, S., Pakina, E.N., Norman, P., Zargar, M., Okbagabir, S.G., Kalabashkina, E.V., & Tsymbalova, V.A. (2025). Fusarium head blight, growth, yield, and quality traits of spring wheat as influenced by variety and cultivation technologies. Journal of Agriculture and Environment, 1(53). https://doi.org/10.60797/JAE.2025.53.3.

(2) Saffa, M.D., Samura, A.E., Bah, M.A., Eni, A.O., Tibiri, E.B., Adama, S., Tiendrébéogo, F., Pita, J.S., Norman, P.E., & Johnson, R.A.B. Detection of Cassava Mosaic Disease and Assessment of Selected Agronomic Traits of Cassava (Manihot esculenta). Horticulturae, 2025, 11, 618. https://doi.org/10.3390/horticulturae11060618

(3) Diakite, S., Kavhiza, N.J., Saquee, F.S., Pakina, E.N., Zargar, M., Diarra, O., Norman, P.E., Traore, B., Samake, F., Daou, C., & Babana, A.H. (2025). Is precision agriculture a viable means of enhancing sustainable agricultural production? Food and Raw Materials Journals, (Accepted)

(4) Ngauja, P.K., & Norman, P.E. (2025). Influence of Staff Recruitment and Staff Retention Strategies on Job Performance in Selected Tertiary Education Institutions in Sierra Leone. European Modern Studies Journal, 9(1), 215–224. DOI:10.59573/emsj.9(1).2025.18

(5) Mabey, P.T., Becker, C., Norman, P.E., & Koroma, B.A. (2025). Environmental and socio-economic impacts of sand mining in selected coastal communities along the western rural-Freetown Peninsular in Sierra Leone. American Journal of Environmental Protection, 13(2, 31-38. DOI:10.12691/env-13-2-1  

(6) Diakite, S., Saquee, F.S., Kavhiza, N.J., Pakina, E.N., Norman, P.E., Chudinova, E.M., Tsindeliani, A.A., & Pototskaya, I.V. (2024). Plant growth and development responses to sulfur nutrition and disease attack under climate change: Role of sulfur and management strategies for wheat and barley. In Press Pedosphere, ….. https://doi.org/10.1016/j.pedsph.2024.12.004

(7) Norman, P.E., Vamboi, W.L., Norman, Y.S.G.E., & Kassoh, F.A. (2024). Assessment of early generation families of white yam (Dioscorea rotundata) for growth and yield parameters. Manuscript Accepted SABRAO Journal of Breeding and Genetics, 56(6), 2284-2294. http://doi.org/10.54910/sabrao2024.56.6.10.

(8) Samura, A.E., Beamah, J., Amara, V., & Norman, P.E. (2024). Efficacy of various diseases management options and evaluation of farmers′ fields for major diseases of rice in Sierra Leone. Annals of Plant Sciences, 13(3), DOI:http://dx.doi.org/10.21746/aps.2024.13.3.3

(9) Norman, P.E., Kamara, L., Beah, A., Gborie, K.S., Saquee, F.S., Kanu, S.A., Kassoh, F.A., Norman, Y.S.G.E., & Kargbo, A.S. (2024). Genetic and agronomic parameter estimates of growth, yield and related traits of maize (Zea mays L.) under different rates of nitrogen fertilization. American Journal of Plant Sciences, 15, 274-291. https://doi.org/10.4236/ajps.2024.154020

(10) Amara, V., Samura, A.E., Norman, P.E., Kanu, S.A., Karim, K.Y., Tiendrebeogo, F., Eni, A.O., & Pita, J.S. (2024). Characterization of the cassava (Manihot esculenta) germplasm in Sierra Leone based on agro-morphological and culinary traits. Horticulturae, 2024, 10, 640. https:// doi.org/10.3390/horticulturae 10060640

(11) Torto, S.J., Sundufu, A.J., Samura, A.E., Fomba, S.N., Musa, D.P., Kanu, S.A., & Norman, P.E. (2024). Oviposition site preference and its effects on subsequent development of variegated grasshopper (Zonocerus variegatus L.) under laboratory conditions. Advances in Entomology, 12(3), 143-154. https://doi.org/10.4236/ae.2024.123011

(12) Samura, A.E., Watson, P.N., Amara, V., Norman, P.E., & Saffa, M.D. (2024). Pests, diseases, growth and yield of tomato as influenced by variety and cultivation technology. Journal of Plant Sciences, 12(5), 122-137. https://doi.org/10.11648/j.jps.20241205.11

(13) Mansaray, S., Norman, P.E., Sherman-Kamara, J., Kamanda, I., & Serry, K.N. (2024). Variation in yellow root cassava (Manihot esculentus Crantz) genotypes and phenotypic relationship for selected postharvest and morphological traits. Agricultural Sciences, 15, 993-1008. https://doi.org/10.4236/as.2024.159053

(14) Torto, S.J., Norman, P.E., Samura, A.E., Fomba, S.N., Musa, D.P., Norman, J.E., & Kanu, S.A. (2024). Grasshopper incidence and severity of damage as influenced by cyanogenic potential in leaf tissue of cassava (Manihot esculenta Crantz). Advances in Molecular Imaging, 13(3), 23-38. doi:10.4236/ami.2024.133003.

(15) Saquee, F.S., Pakina, E., Zargar, M., Norman, P.E., Vladimirovna, K.E., & Alexandrovna, T.V. (2024). Economic parameter estimates of spring wheat varieties grown under different cultivation technologies. Biocatalysis and Agricultural Biotechnology, 62(2024), 103454. https://doi.org/10.1016/j.bcab.2024.103454

(16) Sesay, J.V., Lebbie, A., Wadsworth, R., Nuwamanya, E., Bado, S., & Norman, P.E. (2023). Genetic Structure and Diversity Study of Cassava (Manihot esculenta) Germplasm for African Cassava Mosaic Disease and Fresh Storage Root Yield. Open Journal of Genetics, 13(1), 23-47. https://doi.org/10.4236/ojgen.2023.131002

(17) Torto, S., Samura, A., Sundufu, A., Quee, D., Musa, D., Kanu, S., Fomba, S., & Norman, P. (2023). Grasshopper (Zonocerus variegatus L) Infestation and Root Dry Matter Content of Cassava as Influenced by Planting Date and Cassava Genotypes. Peruvian Journal of Agronomy, 7(1), 42-50. https://doi.org/10.21704/pja.v7i1.2001

(18) Karim, K.Y., & Norman, P.E. (2023). Perceived Knowledge of Cassava Value Chain Actors on Varietal Preferences for Various End Uses. Discoveries in Agriculture and Food Sciences, 11(3), 01-21. DOI:10.14738/dafs.113.14568

(19) Sumana, S.L, Tarawallie, S., & Norman, P.E. (2023). Challenges in Developing Aquaculture for Livelihood Enhancement in Bo City, Southern Sierra Leone. International Journal of Fisheries and Aquaculture Research, 9(1), 1-13. https://doi.org/10.37745/ijfar.15/vol9n1113

(20) Saquee, F.S., Norman, P.E., Saffa, M.D., Kavhiza, N.J., Pakina, E., Zargar, M., Diakite, S., Stybayev, G., Baitelenova, A., & Kipshakbayeva, G. (2023). Impact of different types of green manure on pests and disease incidence and severity as well as growth and yield parameters of maize. Heliyon, 9(6), e17294. https://doi.org/10.1016/j.heliyon.2023.e17294

(21) Torto, S.J., Samura, A.E., Norman, P.E., Sundufu, A.J., Musa, D.P., Kanu, S.A., Quee, D.D., & Fomba, S.N., (2023). Farmers’ perception on severity, crop loss and management practices of variegated grasshopper (Zonocerus variegatus L.) on cassava (Manihot esculenta Crantz) in Sierra Leone. Magna Scientia Advanced Research and Reviews, 2023, 09(01), 034–043. DOI: https://doi.org/10.30574/msarr.2023.9.1.0129

(22) Norman, P.E., Karim, K., Norman, S.G.E., & Vamboi, W.A. (2023). Estimation of genetic parameters for selected quantitative traits in introduced African Yam bean (Sphenosylis stenocarpa Hochst.ex. A. Rich Harms) genotypes. Journal of Tropical Crop Science, 10(3), 217–224.

(23) Saffa, M.D., Saquee, F.S., Norman, P.E., Kavhiza, N.J., Simbo, D., Zargar, M., Lyashko, M., Pakina, E., & Vvedenskey, V. (2023). Influence of field and storage diseases and pests on tuber yield and quality of exotic and local yam (Dioscorea spp.) genotypes. Horticulturae, 2023, 9, 1183. https://doi.org/10.3390/ horticulturae9111183

(24) Norman, P. E., Asfaw, A., Agre, P. A., Danquah, A., Tongoona, P. B., Danquah, E. Y., & Asiedu, R. (2023). Molecular and phenotypic profiling of white Guinea yam (Dioscorea rotundata) breeding lines. Frontiers in Horticulture, 2:1290521. doi: 10.3389/fhort.2023.1290521.

(25) Norman, P.E., Kawa, M.S., & Karim, K.Y. (2022). Effect of Pot Size and Transplanting Date on Tuber Production Using Micro-Tubers of White Yam. Journal of Modern Agriculture and Biotechnology, 1(1):3.DOI:https://www.doi.org/10.53964/jmab.2022003

(26) Barrie, A.U., Norman, P.E., & George, M. (2022). Genetic Parameter Estimates and Diversity Studies of Upland Rice (Oryza sativa L.) Genotypes Using Agro-morphological Markers. International Journal of Agronomy and Agricultural Research (IJAAR), 20(1): 11–23. http://www.innspub.net

(27) Norman, P.E., & Tongoona, P.B. (2022). Genetic parameter estimates and improvement of yam for tuber yield, quality and related attributes: A review. International Journal of Botany Studies, 7(4), 41–49. www.botanyjournals.com

(28) Kanu, M.S., Norman, P.E., & Boima, J.N.S. (2022). Investigating the effect of different rates of chicken manure on the growth, yield and profitability of cowpea (Vigna unguiculata L. Walp) under rain fed condition in the upland soils of Njala, southern Sierra Leone. International Journal of Science and Research, 11(5), 1486–1498. doi:10.21275/SR22101145148.

(29) Norman, P. E., Tongoona, P. B., Danquah, A., Danquah, E. Y., Agre, P. A., Agbona, A., Asiedu, R., & Asfaw, A. (2022). Genetic analysis of agronomic and quality traits from multi-location white yam trials using mixed model with genomic relationship matrix. Global Journal of Botanical Science, 10, 8–22.

(30) Norman, P.E., Agre, P.A., Asiedu, R., & Asfaw, A. (2022). Multiple-Traits Selection in White Guinea Yam (Dioscorea rotundata) Genotypes. Plants, 11, 3003. https://doi.org/10.3390/ plants11213003

(31) Bogba, C., Norman, P.E., Kassoh, F.A., & Kroma, S. (2022). Effect of Leaf Harvest Intensity and Frequency on Sweet Potato Weevil (Cylas puncticollis) Infestation, Yield and Quality Traits of Sweet Potatoes (Ipomoea batatas L.). Journal of Modern Agriculture and Biotechnology, 1(4), 19. DOI: 10.53964/jmab.2022019.

(32) Norman, P.E., Norman, Y.S.G.E., & Bebeley, J.F. (2022). Agronomic and Economic Parameter Estimates of Cocoyam as Influenced by Fertilizer and Environment. American Journal of Agricultural and Biological Sciences, 17(1), 79-89.DOI: 10.3844/ajabssp.2022.79.89

(33) Sesay, J.V., Lebbie, A., Wadsworth, R., Nuwamanya, E., Bado, S., & Norman, P.E. (2023). Genetic Structure and Diversity Study of Cassava (Manihot esculenta) Germplasm for African Cassava Mosaic Disease and Fresh Storage Root Yield. Open Journal of Genetics, 13(1), 23-47. https://doi.org/10.4236/ojgen.2023.131002

(34) Norman, P.E., Tongoona, P.B., Danquah, A., Danquah, E.Y., Asiedu, R., Agbona, A. & Asfaw, A. (2021). Genetic parameter estimation and selection in advanced breeding population of white Guinea yam. Journal of Crop Improvement, 35(6), 790-815. https:// doi.org/10.1080/15427528.2021.1881012

(35) Bebeley, H.A., Mabey, P.T., & Norman, P.E. (2021). Effects of Biochar, Plant Density and Spacing on Growth and Yield of Rice in a Tropical Inland Valley Swamp. International Journal of Applied Agricultural Sciences, 7(2), 77–83. https://doi.org/10.11648/j.ijaas.20210702.11

(36) Karim, K.Y. & Norman, P.E. (2021). Genotype × Environment Interaction and Stability Analysis for Selected Agronomic Traits in Cassava (Manihot esculenta). International Journal of Environmental & Agriculture Research (IJOEAR), 7(8), 17–28.DOI:https://dx.doi.org/10.5281/zenodo.5336002

(37) Samai, M.A., Kassoh, F.A., Kroma, S., Norman, P.E., & Bah, M.A. (2021). Effect of time and proportion of leaf harvest on pest, forage and root yields of sweetpotato (Ipomoea batatas L.) in the inland valley swamp and upland ecologies of Njala. International Journal of Environmental & Agriculture Research (IJOEAR), 7(9), 7–15.DOI:https://dx.doi.org/10.5281/zenodo.5536337

(38) Agre, P.A., Norman, P.E., Asiedu, R., & Asfaw, A. (2021). Identification of Quantitative Trait Nucleotides and Candidate Gene for Tuber Yield and Mosaic Virus Tolerance in an Elite Population of White Guinea Yam (Dioscorea rotundata) using Genome-wide Association Scan. BMC Plant Biology, 21:552. https://doi.org/10.1186/s12870-021-03314-w.

(39) Sesay, M.E., Kanu, E.M., Bagla, V.P., & Norman, P.E. (2021). Prevalence of Brucella abortus in Cattle in the Njala and Newton Ranches of Sierra Leone Using Serological Analysis. Animal and Veterinary Sciences, 9(6): 191–195. doi:10.11648/j.avs.20210906.15

(40) Karim, K.Y., Ifie, B., Dzidzienyo, D., Danquah, E.Y., Blay, E.T., Whyte, J.B.A., Kulakow, P., Rabbi, I., Parkes, E., Omoigui, L., Norman, P.E., & Iluebbey, P. (2020). Genetic characterization of cassava (Manihot esculenta Crantz) genotypes using agro-morphological and single nucleotide polymorphism markers. Physiology and Molecular Biology of Plants, 26(2), 317–330. https://doi.org/10.1007/s12298-019-00740-x

(41) Norman, P.E., Paterne, A.A., Danquah, A., Tongoona, P.B., Danquah, E.Y., De Koeyer, D., Ikeogu, U.N., Asiedu, R., & Asfaw, A. (2020). Paternity Assignment in White Guinea Yam (Dioscorea rotundata) Half-Sib Progenies from Polycross Mating Design Using SNP Markers. Plants, 2020, 9, 527; https://doi:10.3390/plants9040527.

​(42) Karim, K.Y., Norman, P.E., Dzidzienyo, D., Ifie, B., Kulakow, P., Rabbi, I., Omoigui, L., & Parkes, E. (2020). Gene action analysis studies for agronomic traits in cassava (Manihot esculenta Crantz) genotypes developed using line by tester mating design. African Journal of Agricultural Research, 16(10), 1471–1479. doi:10.5897/AJAR2020.14797

(43) Norman, P.E., Danquah, A., Asfaw, A., Tongoona, P.B., Danquah, E.Y., & Asiedu, R. (2020). Seed Viability, Seedling Growth and Yield in White Guinea Yam. Agronomy Journal, 11(2), 1–10. https://dx.doi.org/10.3390/agronomy11010002

(44) Asfaw, A., Aderonmu, S.D., Norman, P.E., Darkwa, K., De Koeyer, D., Paterne Agre, Kouaku, A., Chamber, E., Otoo, E., Obidiegwu, J., Nwanchukwu, E., Dossou-Aminon, I.N., Dansi, A., Oselebe, H., Adebola, P., & Asiedu, R. (2019). Application of predictive breeding in yam improvement for West Africa. Research for Tropical Agriculture, 12(2), 177–120. https://www.jstage.jst.go.jp/article/nettai/12/1/12_43/_article/-char/en

(45) Karim, K.Y., Ifie, B., Dzidzienyo, D., Danquah, E.Y., Blay, E.T., Whyte, J.B.A., Kulakow, P., Rabbi, I., Parkes, E., Omoigui, L., Norman, P.E., & Iluebbey, P. (2020). Genetic characterization of cassava (Manihot esculenta Crantz) genotypes using agro-morphological and single nucleotide polymorphism markers. Physiology and Molecular Biology of Plants, 26(2), 317–330. https://doi.org/10.1007/s12298-019-00740-x

(46) Norman, P.E., Paterne, A.A., Danquah, A., Tongoona, P.B., Danquah, E.Y., De Koeyer, D., Ikeogu, U.N., Asiedu, R., & Asfaw, A. (2020). Paternity Assignment in White Guinea Yam (Dioscorea rotundata) Half-Sib Progenies from Polycross Mating Design Using SNP Markers. Plants, 2020, 9, 527; https://doi:10.3390/plants9040527.

(47) Karim, K.Y., Norman, P.E., Dzidzienyo, D., Ifie, B., Kulakow, P., Rabbi, I., Omoigui, L., & Parkes, E. (2020). Gene action analysis studies for agronomic traits in cassava (Manihot esculenta Crantz) genotypes developed using line by tester mating design. African Journal of Agricultural Research, 16(10), 1471–1479. doi:10.5897/AJAR2020.14797

​(48) Norman, P.E., Asfaw, A., Tongoona, P.B., Danquah, A., Danquah, E.Y., Koeyer, D.D., & Asiedu, R. (2018). Can parentage analysis facilitate breeding activities in root and tuber crops? Agriculture Journal, 8(95), 1–24. https://dx.doi.org/10.3390/agriculture8070095

(49) Norman, P.E., Asfaw, A., Tongoona, P.B., Danquah, A., Danquah, E.Y., De Koeyer, D., & Asiedu, R. (2018). Pollination success in some white yam genotypes under polycross and nested mating designs. International Journal of Biological Sciences and Applications, 5(2), 19–28. https://www.aascit.org/journal/ijbsa

(50) Sesay, J.V., Ayeh, K.O., Norman, P.E., & Acheampong, E. (2016). Shoot nodal culture and virus indexing of selected local and improved genotypes of cassava (Manihot esculenta) from Sierra Leone. International Journal of Biotechnology and Molecular Biology Research, 7(2), 20–28. https://doi.org/10.5897/IJBMBR2015.0245

(51) Kroma, S., Norman, P.E., Barrie, A.U., & Norman, S.Y. (2016). Efficacy of chicken manure on the growth, yield and profitability of maize in the upland and inland valley swamp of Sierra Leone. International Journal of Sciences, 5(11), 7–13. DOI: 10.18483/ijSci.1116

(52) Beah, A.A., Norman, P.E., Scholberg, J.C., Lantinga, E.A., & Conteh, A.R. (2015). Effect of Organic Manure on Nitrogen Mineralization, Nitrogen Accumulation, Nitrogen Use Efficiency and Apparent Nitrogen Recovery of Cauliflower (Braccica oleracea L., var. Botrytis). International Journal of Plant and Soil Sciences, 4(3), 265–272.  http://www.sciencedomain.org/review-history/6552

(53) Norman P.E., Whyte, J.B.A., Samura, A.E., Massaquoi, A., Sesay, L., Dixon, A.G.O., Fomba, S.N., Benya, M.T., & Sowa, M.M. (2015). Effect of staking and non-staking systems on disease severity, yield and quality attributes of yams (Dioscorea alata). Journal of Agriculture and Ecology Research International, 2(4), 219–229.DOI:10.9734/JAERI/2015/14713

(54) Norman P.E., Bebeley, J.F., Beah, A.A., & Sellu, E.F. (2015). Assessment of agro-morphological diversity and affinities in cocoyam species from Sierra Leone. International Journal of Biodiversity and Conservation, 7(10), 408–419. DOI: 10.5897/IJBC2015.0883

(55) Beah, A.A., Norman, P.E., Scholberg, J.C., Lantinga, E.A., & Conteh, A.R. (2014). Effect of green manures on nitrogen uptake and yield of cauliflower (Brassica oleracea var. botrytis). International Journal of Applied Agricultural Research, 9(1), 73–84. http://www.ripublication.com

(56) Norman, P.E., Beah, A.A, Samba, J.A., Tucker, M.J., Lissa, J., Koroma, F., Benya, M.T., & Fomba, S.N. (2014). Agro-phenotypic characterization of sweet potato (Ipomoea batatas L.) genotypes using factor and cluster analyses. Agricultural Science Research Journals, 4(2), 30-38. Available online at http://www.resjournals.com/ARJ

(57) Beah, A.A., Norman, P.E., Scholberg, J.C., Lantinga, E.A., & Conteh, A.R. (2014). Effect of organic manures on soil bio-physical properties and dry matter partitioning in cauliflower, International Journal of Plant and Soil Sciences, 3(9), 1044–1054.DOI:10.9734/IJPSS/2014/11256

(58) Sesay, L., Norman, P.E., Massaquoi, A., Kobba, F., Allieu, A.P, Gboku, M.L., & Fomba, S.N. (2013). Assessment of farmers’ indigenous knowledge and selection criteria of yam in Sierra Leone. Sky Journal of Agricultural Research 2(1): 1–6. http://www.skyjournals.org/SJAR

(59) Norman, P.E., Tongoona, P., & Shanahan, P.E. (2011). Diversity of morphological traits of yam (Dioscorea spp.) genotypes from Sierra Leone. Journal of Applied Biosciences 45: 3045–3058.https://www.semanticscholar.org/paper/Diversity-of-the-morphological-traits-of-yam-spp.%29-Norman-Tongoona/f594a878196196eb30a1d4fc5d523cd65cbeba19

​(60) Norman, P.E., Tongoona, P., & Shanahan, P.E. (2011). Determination of interrelationships among agro-morphological traits of yams (Dioscorea spp.) using correlation and factor analyses. Journal of Applied Biosciences, 45, 3059–3070. at www.biosciences.elewa.org or https://www.semanticscholar.org/paper/Determination-of-interrelationships-among-agro-of-Norman-Tongoona/568f8f328506e97c8ced71fa61c9fc0456cb619e

(61) Lahai, M.T., Alpha, M.G., Boima, B., & Norman, P.E. (2006). Effect of time of Debudding and planting density on the growth and yield of okra during the wet and dry seasons. Journal of Pure and Applied Science, 10, 79-86.

(62) Norman, P.E., Tongoona, P., & Shanahan, P.E. (2012). Determination of associations between three morphological and two cytological traits of yams (Dioscorea spp.) using canonical correlation analysis, African Journal of Agricultural Research, 7(17), 2674–2678. DOI: 10.5897/AJAR11.1299

(63) Norman, P.E., Tongoona, P., & Shanahan, P.E. (2012). Diversity in chromosome number and raphide morphology of yam (Dioscorea spp.) genotypes from Sierra Leone. African Journal of Plant Science, 6(4), 157–160. DOI:10.5897/AJPS11.247

(64) Norman, P.E., Tongoona, P., Danson, J., & Shanahan, P.E. (2012). Molecular characterization of some cultivated yam (Dioscorea spp.) genotypes in Sierra Leone using simple sequence repeats. International Journal of Agronomy and Plant Production, 3(8), 265–273. http://ijappjournal.com/…/265-273.pdf

(b) Book chapter publications

(1) Norman, P.E., Bebeley, J.F., Sesay, J.V., & Norman, Y.S. (2019). Biodiversity in Sierra Leone. In: Global biodiversity Vol. 3: Selected Countries in Africa T. Pullaiah (ed.). Apple Academic Press, p. 213–244.https://www.appleacademicpress.com/global-biodiversity-volume-3-selected-countries-in-africa/9781771887229

(2) Norman, P.E., Johnny, J., Moiforay, S.K., & Norman, Y.S.G.E. (2021). Invasive Alien Species of Sierra Leone. In: Invasive Alien Species. Observations and issues from around the world Vol. 1: Issues and Invasions in Africa, T. Pullaiah and Michael R. Ielmini (eds.). John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, USA, p. 242–262. DOI:10.1002/9781119607045.ch8

​(3) Norman, P.E., Karim, K.Y., & Dzidzienyo, D. (2021). Assessing mating designs utilized in cassava population improvement (Chapter 5). In: Cassava, Biology, Production, and Use. Andri Frediansyah (ed.). IntechOpen Ltd. Janeza Trdine 9, 51000 Rijeka, Croatia. pp.91–111. http://dx.doi.org/10.5772/intechopen.96785.

(4) Norman, P.E., Dzidzienyo, D., Karim, K.Y., & Beah, A. (2021). Genetic Modification and Application in Cassava, Sweetpotato and Yams. In: Genetically Modified Plants and Beyond.  Idah Sithole-Niang (ed.). 24p. DOI:http://dx.doi.org/10.5772/intechopen.101037. IntechOpen Ltd. Janeza Trdine 9, 51000 Rijeka, Croatia.

(5) Norman, P.E., Okoni-Williams, A., James M.S., Norman, Y.S.G.E., & Luseni, M.M. (2023). The Role of Botanical Gardens in Plant Diversity Conservation of Sierra Leone (Chapter 8), pp. 129-139. In: Botanical Gardens and their Role in Plant Conservation Volume 1 General Topics, African and Australian Botanical Gardens. T. Pullaiah and David A. Galbraith (eds.). CRC Press, Routledge, Taylor and Francis Group, USA, 272 pp. https://www.nhbs.com/botanical-gardens-and-their-role-in-plant-conservation-volume-1-book

(c) Book abstract publications

(1) Norman, P. E., Asfaw, A., Tongoona, P. B., Danquah, A., Danquah, E. Y., De Koeyer, D.& Asiedu, R. (2017). Pollination success and seed set in some white yam (Dioscorea rotundata) genotypes assessed under different mating system. Presented at the 20th Annual IARSAF Symposium, IITA, Ibadan, Nigeria on 10th-14th July, 2017. p 15.

(2) Norman, P.E., Asfaw, A., Tongoona, P.B., Danquah, A., Danquah, E.Y., Agre, A.P., Agbona, A. & Asiedu, R. (2018). Estimates of Genetic Components for Growth, Reproductive, Yield and Quality Traits of Yam (Dioscorea rotundata). Poster Presentation at the International Conference on Food and Nutrition Security in Africa held at WACCI Auditorium, University of Ghana, on 3rd-5th October, 2018.p 70.

(3) Norman, P.E., Asfaw, A., Tongoona, P.B., Danquah, A., Danquah, E.Y., Agre, A.P., & Asiedu, R. (2019). Application of a Mixed Model with Genomic Relationship Matrix and the Multivariate Techniques for Analysis of Agronomic and Quality Traits in White Guinea Yam (Dioscorea rotundata Poir.) Breeding Trials. In: Maiden International Conference Proceedings of the African Plant Breeders Association titled “Advances in Classical Breeding and Application of Modern Breeding Tools for Food and Nutrition Security in Africa” held at the University of Ghana, Accra, Ghana on the 23rd – 25th, October, 2019. p 13.

(4) Norman, P.E., Agre, A.P., Danquah, A., Tongoona, P.B., Danquah, E.Y., De Koeyer, D., Ikeogu, U.N., Asiedu, R., & Asfaw, A. (2021). Pollination success, paternity test and seedling traits assessments in white yam (Dioscorea rotundata) progenies generated using nested and polycross mating designs. In: Book of Abstract Online Summit on Plant Science and Agriculture organized by Science Technology, Engineering and Mathematics (STEM) International Organization. 21 pp.

(5) Norman, P.E., Asfaw, A., Danquah, A., Agre, A.P., Tongoona, P.B., Danquah, E.Y., Agbona, A., Asiedu, R., & Matsumoto, R. (2021). Trait profiling of white Guinea yam (Dioscorea rotundata) breeding lines using breeding values and genomic estimated breeding values. Book of Abstract Online Summit on Plant Science and Genomics organized by Coalesce Research Group, 33 Market Point Dr, Greenville, SC 29607, USA. p 34. 2nd Webinar on Plant Science & Genomics, April 29 – 30, 2021.
(6) Agre, P.A., Norman, P.E., Asfaw, A., & Asiedu, R. (2021). Identification of Quantitative Trait Nucleotides and Candidate Gene for Tuber Yield and Mosaic Virus Tolerance in an Elite Population of White Guinea Yam (Dioscorea rotundata) using Genome-wide Association Scan. Genomics and Molecular Biology Summit (GMB-2021) September 28th, 2021. Hosed by STEM International Organization. www.stemio.org.p8.

(7) Norman, P.E., Kamara, L., Gborie, K., Kargbo, A.S., Saquee, F.S., Norman, Y.S.G.E., & Beah, A (2023). Influence of variety and rates of nitrogen fertilization on grain yield and agronomic parameter estimates of maize (Zea mays L.). In: Proceedings of the 10th International Conference on Agriculture 2023(AGRICO 2023) 21st – 22nd September 2023, Jakarta, Indonesia. p 30. Co-hosted by The South-South Aquaculture and Fisheries Cooperation, Bulacan Agricultural State University, Philippines and Universitas Andalas, Indonesia. The Conference is organized by The International Institute of Knowledge Management (TIIKM) in collaboration with; Maharana Pratap University of Agriculture and Technology, India, Poznań University of Life Sciences, Poland, Southern Leyte State University, Philippines, Georgian Technical University, Georgia, Sher-e-Bangla Agricultural University (SAU), Bangladesh, College of Agriculture, Don Mariano Marcos Memorial State University La Union, Philippines, Palestine Technical University Kadoorie, Palestine and Field Crops Research Institute, and Agricultural Research Center, Egypt.

(d) Publications in international conference proceedings

1. Fomba, S.N., Massaquoi, F.B., Norman, P.E., Samura, A.E., Mansaray, A., Jalloh, A., Dixon, A.G.O., Anthony, N.A., Benya, M.T., Fornah, D.S., Sawi, M.K., Sartie, A., Alenkhe, B., Onadipe, O., & Sanni, L.O. (2012). Current status of root and tuber crops improvement, production and utilization in Sierra Leone. In: Proceedings of the 11th Triennial Poster presentation at the 11th Symposium of ISTRC-AB, Memling Hotel, Kinshasa, DR Congo, 4th-8th October 2010. Pp 134-150.
2. Fomba, S.N., Whyte, J.B.A., Massaquoi, F.B., Norman, P.E., Samura, A.E., Mansaray, A., Anthony, N.M., Benya, M.T., Dixon, A.G.O., Gboku, M.L.S., Fornah, D.S., Sesay, L., Massaquoi, A., & Kobba, F. (2013). Advances in Cassava (Manihot esculenta Crantz) and Yam (Dioscorea spp.) Breeding and Development in Sierra Leone: 2008-2012. In: Proceedings of the 12th Triennial Symposium of ISTRC-AB, Alisa Hotel, Accra, Ghana, 3rd-6th October 2013.
3. Norman, P.E., Whyte, J.B.A., Samura, A.E., Massaquoi, A., Sesay, L., Dixon, A.G.O., Fomba, S.N., Benya, M.T., & Sowa, M.M. (2013). Evaluation of introduced yam genotypes in three agro-ecologies of Sierra Leone. In: Proceedings of the 12th Triennial Symposium of ISTRC-AB, Alisa Hotel, Accra, Ghana, 3-6 October 2013.
4. Norman, P. E., Asfaw, A., Tongoona, P. B., Danquah, A., Danquah, E. Y., De Koeyer, D.& Asiedu, R. (2017). Pollination success and seed set in some white yam (Dioscorea rotundata) genotypes assessed under different mating system. Presented at the 20th Annual IARSAF Symposium, IITA, Ibadan, Nigeria on 10th-14th July, 2017.
5. Norman, P. E., Asfaw, A., Tongoona, P. B., Danquah, A., Danquah, E. Y., Agre, A. P., Agbona, A. & Asiedu, R. (2018). Estimates of Genetic Components for Growth, Reproductive, Yield and Quality Traits of Yam (Dioscorea rotundata). Poster Presentation at the International Conference on Food and Nutrition Security in Africa held at WACCI Auditorium, University of Ghana, on 3rd-5th October, 2018.
6. Asfaw, A., Aderonmu, S. D., Norman, P. E., Darkwa, K., De Koeyer, D., Agre, A. P., Kouaku, A., Chamber, E., Otoo, E., Obidiegwu, J., Nwanchukwu, E., Dossou-Aminon, I. N., Dansi, A., Oselebe, H., Adebola, P. & Asiedu, R. (2018). Application of predictive breeding in yam improvement for West Africa. Oral Presentation at the 2nd International Yam Crop Science Workshop at Tokyo University of Agriculture (TUA), Setagaya, Tokyo, Japan, on 8th-12th March, 2018.
7. Norman, P. E., Asfaw, A., Tongoona, P. B., Danquah, A., Danquah, E. Y., Agre, A. P., Agbona, A. & Asiedu, R. (2019). Application of a mixed model with genomic relationship matrix and the multivariate techniques for analysis of agronomic and quality traits in white Guinea yam (Dioscorea rotundata Poir.) breeding trials. Oral Presentation at the African Plant Breeders Association (APBA) Maiden International Conference Held at Auditorium of the Department of Economics University of Ghana, Accra, Ghana. October 23-25, 2019; on the theme: Advances in Classical Breeding and Application of Modern Breeding Tools for Food and Nutrition Security in Africa.
8. Agre, P.A., Norman, P.E., Asfaw, A. and Asiedu, R. (2021). Identification of Quantitative Trait Nucleotides and Candidate Gene for Tuber Yield and Mosaic Virus Tolerance in an Elite Population of White Guinea Yam (Dioscorea rotundata) using Genome-wide Association Scan. Genomics and Molecular Biology Summit (GMB-2021) September 28th, 2021. Hosted by STEM International Organization. www.stemio.org.
9. Norman, P.E., Kamara, L., Gborie, K., Kargbo, A.S., Saquee, F.S., Norman, Y.S.G.E., & Beah, A (2023). Influence of variety and rates of nitrogen fertilization on grain yield and agronomic parameter estimates of maize (Zea mays L.). In: Proceedings of the 10th International Conference on Agriculture 2023(AGRICO 2023) 21st – 22nd September 2023, Jakarta, Indonesia. p 30. In: Global Food Security: Stopping Crop LossesCo-hosted by The South-South Aquaculture and Fisheries Cooperation, Bulacan Agricultural State University, Philippines and Universitas Andalas, Indonesia. The Conference is organized by The International Institute of Knowledge Management (TIIKM) in collaboration with; Maharana Pratap University of Agriculture and Technology, India, Poznań University of Life Sciences, Poland, Southern Leyte State University, Philippines, Georgian Technical University, Georgia, Sher-e-Bangla Agricultural University (SAU), Bangladesh, College of Agriculture, Don Mariano Marcos Memorial State University La Union, Philippines, Palestine Technical University Kadoorie, Palestine and Field Crops Research Institute, and Agricultural Research Center, Egypt.

(e) Publications in Annual Reports

Norman, P.E., and Conteh, A.R. (2022). Estimation of genetic parameters for selected quantitative traits in introduced African Yam bean (Sphenosylis stenocarpa Hochst.ex. A. Rich Harms) genotypes.

Norman, P.E., & Samura, A.E. (2004). Evaluation of Improved yam genotypes in Sierra Leone. Annual Report of the Institute of Agricultural Research (IAR), Sierra Leone.

Norman, P.E., & Samura, A.E. (2006). Evaluation of Introduced Yam Genotypes for Pest and Disease Resistance, Root and Food Quality Traits. Annual Report of the Institute of Agricultural Research (IAR), Sierra Leone.

Norman, P.E., Samura, A.E., & Mansaray, A. (2007). Screening sweet potato genotypes for its Genetic potential for breeding. Annual Report of the Institute of Agricultural Research (IAR), Sierra Leone.

Norman, P.E., Samura, A.E., & Mansaray, A. (2007). Multivariate analysis of phenotypic             diversity in yam (Dioscorea spp.) germplasm. Annual Report of the Institute of Agricultural Research (IAR), Sierra Leone.

Norman, P.E., Samura, A.E., & Mansaray, A. (2007). Assessment of sweet potato Advanced Yield Trials. Annual Report of the Institute of Agricultural Research (IAR), Sierra Leone.

Norman, P.E., Samura, A.E., & Mansaray, A. (2008). Participatory variety selection on yam in Moyamba. Annual Report of Njala Agricultural Research Centre (NARC), Sierra Leone. Pp 10-16.

Norman, P.E., Bebeley, J., Massaquoi, F.B., Samura, A.E., Mansaray, A., & Fomba, S.N. (2011). Preliminary investigation of introduced yam productivity and profitability in Sierra Leone. Annual Report of Njala Agricultural Research Centre (NARC), Sierra Leone. Pp 30-43.

Norman, P.E., Sowa, M., Samura, A.E., Mansaray, A., & Fomba, S.N. (2012). Screening of introduced yam genotypes for yield, pest and diseases resistance and food quality traits under staking and non-staking conditions.

Norman, P.E., Samura, A.E., Mansaray, A., Anthony, N., Benya, M.T., Fomba, S.N., & Sowa, M. (2013). Evaluation of introduced yam genotypes in three agro-ecologies of Sierra Leone. Annual Report of Njala Agricultural Research Centre (NARC), Sierra Leone.

Sesay, L., Norman, P.E., Massaquoi, A., Kobba, F., Allieu, A.P., Gboku, M.L., & Fomba, S.N. (2013). Assessment of farmers’ indigenous knowledge and selection criteria of yam in Sierra Leone. Annual Report of Njala Agricultural Research Centre (NARC), Sierra Leone.

Norman, P.E., Asfaw, A., Danquah, A., Agre, P.A., Tongoona, P.B., Danquah, E.Y., Agbona, A., Asiedu, R., and Matsumoto, R. (2020). Molecular and phenotypic profiling of white Guinea yam (Dioscorea rotundata) breeding lines.

Norman, P.E., Asfaw, A., Danquah, A., Agre, P.A., Tongoona, P.B., Danquah, E.Y., De Koeyer, D., Ikeogu, U.N., Asiedu, R., and Asfaw, A. (2020). Paternity Assignment in White Guinea Yam (Dioscorea Rotundata) Half-Sib Progenies from Polycross Mating Design Using SNP Markers.

Agre, P.A., Norman, P.E., Asfaw, A., Asiedu, R., and Agbona, A. (2020). Identification of Quantitative Trait Nucleotides and Candidate Gene for Tuber Yield and Mosaic Virus Tolerance in an Elite Population of White Guinea Yam (Dioscorea rotundata) using Genome-wide Association Scan.

Norman, P.E., Tongoona, P.B., Danquah, A., Danquah, E.Y., Agre, P., Agbona, A., Asiedu, R., and Asfaw, A. (2020). Genetic parameter estimation and selection in an advanced breeding population of white Guinea yam.

Norman, P.E., Kamanda, I., and Conteh, A.R. (2020). MAF/SLARI- COVID-19 Emergency Response Food Production and Multiplication Project: SAH yam micro-tubers and plantlets, and botanical seeds.

Norman, P.E. and Conteh, A.R. (2020). Evaluation of introduced white yam genotypes in Sierra Leone.

Norman, P.E., Vamboi, W.L., Kassoh, F.A., and Conteh, A.R. (2021). Assessment of Growth and Yield Parameters of Early Generation Families of White Yam (Dioscorea rotundata).

Norman, P.E., Kawa, M.S., Karim, K.Y., and Conteh, A.R. (2021). Effect of Pot Size and Transplanting Date on The Yield of Introduced SAH Derived Micro-Tubers of White Yam.

Norman, P.E., Turay, I.S., Kroma, S., and Conteh, A.R (2021). Phenotypic Variability Studies in Introduced Dioscorea rotundata (White Yam) Genotypes.

Norman, P.E., Kamara, F.I., Kroma, S., and Conteh, A.R. (2021). Genetic Parameter Estimates and Correlations in Introduced Dioscorea Rotundata (White Yam) Genotypes.

Norman, P.E., Yawulie, B., Karim, K.Y., and Conteh, A.R. (2021). Assessment of Growth and Reproductive Traits of Some Introduced Varieties of African Yam Bean (Sphenosylis stenocarpa Hochst.ex. A. Rich Harms).

Norman, P.E., Kamara, F.K., Karim, K.Y., and Conteh, A.R. (2021). Evaluation of Seedling Traits of Some Introduced Varieties of African Yam Bean (Sphenosylis stenocarpa Hochst.ex. A. Rich Harms).

Norman, P.E., Bah, M., Karim, K.Y., and Conteh, A.R. (2022). Effects of set size on sprouting, growth, yield and related traits of semi-autotrophic derived white yam (Dioscorea rotundata) genotype.

Norman, P.E., Karfo, C., Karim, K.Y., and Conteh, A.R. (2022). Sprouting, growth, yield and related traits as influenced by planting materials (bulbils, seed yams, head, middle and tail portions) of water yam (Dioscorea alata).

Norman, P.E., Alie, F.B., Kassoh, F.A., and Conteh, A.R. (2022). Assessment of growth and yield parameters of tuber families of white yam (Dioscorea rotundata).

Norman, P.E., and Conteh, A.R. (2022). Seedling vigour index and tuber yield traits as influenced by genotype and pre-sprouted sett and direct planted planting materials.