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Morphological characteristics of some African materials of Bambara peanut (Vigna subterranea (L.) verdc.)

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https://www.eduzhai.net International Journal of Plant Research 2017, 7(2): 29-35 DOI: 10.5923/j.plant.20170702.01 Morphological Characterisation of Selected African Accessions of Bambara Groundnut (Vigna subterranea (L.) Verdc.) John Olayinka Atoyebi1,2,*, Olaniyi Oyatomi3, Odutola Osilesi1, Olugbenga Adebawo4, Michael Abberton3 1Department of Biochemistry, Babcock University, Ilisan - Remo, Nigeria 2National Centre for Genetic Resources and Biotechnology (NACGRAB), Moor – Plantation, Ibadan, Nigeria 3Genetic Resources Centre, International Institute of Tropical Agriculture, (IITA), Ibadan, Nigeria 4Department of Biochemistry, Olabisi Onabanjo University, Ikenne - Remo, Nigeria Abstract Three hundred (300) accessions of Bambara groundnut (Vigna subterranea (L.) Verdc) among the 1973 maintained in the global repository at the International Institute of Tropical Agriculture (IITA), Ibadan, genebank were selected for this study. Two to three seeds of each accession were planted during the 2014 / 2015 planting season at IITA, Ibadan, Nigeria. Seedlings were thinned to a single plant prior to flowering. Thirty - seven (37) agro-morphological parameters, representing 28 quantitative and 9 qualitative traits were recorded on each plant (IPGRI, 2000). The data were subjected to analysis using the statistics application system (SAS) software, version 9.3, both to depict correlation among parameters and eigen values with principal component on scree plot and dendrogram construction. The results revealed lines (e.g TVSu – 293, TVSu – 395, TVSu – 1243) that had high yield potentials. Also, TVSu -397 and TVSu – 1168 had the highest number of leaves while TVSu – 520 and TVSu – 1022 had the least. The least number of seeds per plant was given by TVSu – 1, TVSu – 353 and TVSu – 454, while TVSu – 395, TVSu – 618 and TVSu – 1897 gave the highest number of seeds at harvest. The result provides information necessary for future nutrition and breeding studies on Bambara groundnut and its improvement. Keywords Bambara groundnut, Agro-morphology, Accessions, Quantitative Parameters, Dendrogram 1. Introduction There is need for the adaptation of agriculture to the changing climatic conditions which will enhance the utilisation and promotion of suitable crops and tree species. These includes the group of under-utilised and neglected species (NUS), as well as the wild relatives of crops (CWR), which all constitute an important tasks for future agricultural practices [12]. Research into NUS is especially important and necessary, due to the need to secure the basis of food production and thus help to provide a balanced nutritional diet for the rural population of many developing countries, like Nigeria, Bukina-faso and Mali in Africa [14]. Important components of agro-biodiversity are the neglected and under-utilised plants (NUS) as these have traits and properties that are important to provide varied and nutritionally balanced diets. These species are often traditionally used, or are wild species that already * Corresponding author: johnatoyebi@ymail.com (John Olayinka Atoyebi) Published online at https://www.eduzhai.net Copyright © 2017 Scientific & Academic Publishing. All Rights Reserved contribute to a balanced diet, especially for poor people. They also often possess other important properties including the potential to adapt farming to future climates, such as tolerance to biotic and abiotic constraints, medicinal properties, as well as resistance genes against certain pests and diseases, thereby helping to enhance increased food sufficiency through reduced losses, leading to increased production and consumption [14, 17]. Neglected and under-utilised species are comprised of a broad category of agricultural and wild crops in which they exists as either traditional crops that are still being cultivated by farmers or grow as wild vegetables or crops [1, 7, 8]. Here, farmers have an important role to play as custodians of these traditional crops and planting material, as well as for other NUS species and vegetables [12]. However, this responsibility should not only be saddled with farmers alone, but must be supported with other governmental intervention, that will enable profitable policies to benefit the entire value chain of these NUS. Another important stakeholder is the private sector, as they serve as possible ‘engine’ for delivery of these products, especially when it comes to product utilization; thus serving as a possible bridge between the farmers and the consumers. Studies of 30 John Olayinka Atoyebi et al.: Morphological Characterisation of Selected African Accessions of Bambara Groundnut (Vigna subterranea (L.) Verdc.) agro-morphological parameters have been an important approach in exploiting the genetic diversity of crops. This especially makes under-utilised crops more attractive to farmers through identifying appropriate morphotypes and farming practices that can help to determine the choice of germplasm to be used in specific climatic condition studies or in nutrition related research. The creation of options for farmers in the agricultural production system is essential, as it drives the ability of society to address diverse livelihood problems, through the farming system and genetic diversity created; thus enhancing the popularity of such crops for consumption [14]. The sustainable conservation and utilisation of plant genetic diversity and the characterisation of NUS are an important means of achieving food security. The global population grows by an estimated 80 million people a year and is expected to reach 9.2 billion by 2050 [13]. Thus, in preparing for global increases in population, NUS like Bambara groundnut (Vigna subterranea) can serve as a way to address certain deficiencies in the predominant consumption of major crops and diets focused on a limited number of species like rice, wheat and maize; as these NUS possesses the potential to solve numerous nutritional challenges and enhance food security in developing countries. Studies have shown that in West Africa, where most of the Bambara groundnut is being grown, the crop is prominent among the traditionally cultivated food species in rural communities. For example, the crop plays a key role in the traditional food and culture of the people in the western and northern parts of Cote d’Ivoire [17]. Three hundred accessions of Bambara groundnut from different African countries, were selected from the collections at the Genetic Resources Centre (GRC) in the International Institute of Tropical Agriculture, (IITA) in Ibadan, Nigeria. descriptive statistics, one way analysis of variance (ANOVA) and principal component analysis was done with subsequent correlation coefficients utilized to construct a dendrogram so as to view the groupings and relatedness among these collections of Bambara groundnut viz a viz the different yield parameters and their country of origin. Also Microsoft excel 2010 was used for data entry and simple charts. Figure 1. Phenotypic variations among African Bambara groundnut collections 2. Materials and Methods Three hundred (300) accessions of Bambara groundnut (Vigna subterranea), all representing the African accessions in the collection that were domiciled at the Genetic Resources Centre, IITA, Ibadan, Nigeria, (latitude 7° 30 ′ N and longitude 3° 54 ′E). (2-3) seeds of each of the accession were planted during the 2014 / 2015 planting season. Prior to flowering, each accession was thinned to single plants and watered twice a week for the first two months and then reduced to once a week until harvest. According to the Bambara groundnut descriptors, (Bioversity descriptor, 2000), thirty-seven (37) important agro-morphological parameters, representing twenty-eight (28) quantitative traits and nine (9) qualitative ones were taken from the date of planting until harvest. Fourteen (14) important ones out of these parameters were chosen for statistical analysis. 2.1. Statistical Analysis Data were analysed using the Statistical Analysis System (SAS) software package version 9.3 to determine the Figure 2. Bambara groundnut (at 7 weeks growth at IITA, field) 3. Results and Discussion Bambara groundnut is a crop that is widely grown in Nigeria [19]; and other African countries and has become an important NUS. This legume, predominant in sub – Saharan Africa still exhibits immense untapped potentials. The current paper presents research work on agro – morphological performance of 300 African accessions, with the aim of revealing the variability that exists for traits of agricultural importance in this crop with the aim of selection for nutrition parameters and analysis. This will also further aid selection of elite materials in breeding and agricultural improvement programs. From Table 1 shows the mean values of the parametric indices measured; while Table 2 depicts the linear relationship among the chosen parameters. The results of the morphological evaluation revealed mean values for the number of flowers (NFP) to be International Journal of Plant Research 2017, 7(2): 29-35 31 very few. The number of leaves (NL) had values of wide discrepancies as some were few, while others were numerous, well above 100. The terminal leaf length (TLL) and width (TLW) had scanty and small mean values. The petiole length (PETL) had slightly varied values while those for the plant height (PH) had greater deviations among its values. Also, days to maturity (DM) parameter had a mean value of 134 days for all the collections under evaluation. The results also showed that among all the parameters taken, the number of days to emergence (TDE) had the least variability among its values, while the number of leaves (NL) values exhibited the highest level of variability among its values for the 300 lines evaluated. With respect to inter-relationships among parameters, there was no relationship between the terminal leaf length (TLL) and petiole length (PETL), while the correlation matrix values obtained suggested a relationship between plant height (PH) and peduncle length (PL). There was a positive correlation between the nodulation capacity (NC) and the number of flowers per peduncle (NFP). Among all the yield parameters evaluated across countries of selections, accessions from Cameroon displayed a range in pod length and width from 9.70 mm to 21.0 mm and 8.34 mm to 10.95 mm respectively, while its total seed weight ranged from 0.21g to 5.14 g. Those collections from Nigeria had a range of pod length and width of 10.0 mm to 21.3 mm and 6.0 mm to 14.15mm respectively, while total seed weight ranged from 0.53 g to 3.28 g. The accessions from Zambia gave a range of pod length and width of 9.60 mm to 18.99 mm and 6.70 mm to 10.85 mm respectively, while its total seed weight ranged from 0.25g to 4.25g. Also Zimbabwean accessions gave a range of pod length and width from 9.05 mm to 15.5 mm and 7.09 mm to 12.28 mm respectively, while its total seed weight ranged from 0.20 g to 2.27 g. From the principal components (Fig. 3) and the cluster analysis presented as a dendrogram (Fig. 4) revealed numerous clusters depicting relationships among these collections. It shows that there are at least fifteen main clusters, without counting the numerous sub–clusters and the overlapping ones. Predominant among these were TVSu – 1290 with TVSu – 1284; also TVSu – 1850 showed a close relationship with TVSu – 1789. Furthermore the three clusters showing different groupings for TVSu – 1187, TVSu – 1180; TVSu – 1027, TVSu – 1026; and TVSu – 1262, TVSu – 1243 seemed to be exhibiting the greatest proximity with closest relationships among all the clusters observed, while TVSu – 156 formed its own cluster. The results of this work further indicated the importance of the crop as revealed by its genetic variabilities and performance in the study. The selected 300 accessions in this study could be of immense benefit for the crop in a developing country like Nigeria. The collected African accessions examined indicated qualitative potentials for some lines such as TVSu – 293 (Bukina – Faso); TVSu – 395 (Cameroon) and TVSu – 1243 (Nigeria). Also, TVSu – 397 (Cameroon) and TVSu – 1168 (Bukina – Faso) had the highest number of leaves, while TVSu – 520 (Cameroon) and TVSu – 1022 (Zimbabwe) gave the least. The least number of seeds were given by TVSu – 1 and TVSu – 353 (Nigeria) and TVSu – 454 (Cameroon); while TVSu – 395 (Cameroon), TVSu – 618 (Nigeria) and TVSu – 1897 (Botswana) had the highest number of pods and seeds. The results of this study revealed certain potentials in some of the Bambara groundnut lines evaluated as earlier enumerated, which forms the basis of selection for future nutrition analysis, as well as in breeding and other Bambara groundnut improvement research. Table 1. Summary of the mean values of the selected morphological parameters S/N Descriptors 1 Date of emergence 2 Peduncle length 3 No flowers/pedcle 4 No of leaves 5 Terminal leaf lnt 6 Terminal leaf wdth 7 Petiole length 8 Plant spread 9 Plant height 10 Nodulation capacity 11 Intemode length 12 No days to flower 13 No days to 50% flower 14 No days maturity Mean ± SEm 8.01 ± 0.046 12.23 ± 0.153 1.39 ± 0.031 82.91 ± 1.81 52.52 ± 0.814 18.89 ± 0.272 69.77 ± 1.529 22.58 ± 0.304 17.30 ± 0.147 3.13 ± 0.120 10.92 ± 0.114 37.08 ± 0.221 55.02 ± 0.232 134.45 ± 0.281 Maximum 9 22 2 156 81 35 140 40 34.5 7 20 50 71 141 Minimum 7 7 1 15 20 5 25 12 13 0 8 33 52 129 S.D 0.80 2.65 0.54 31.51 14.10 4.72 26.49 5.27 2.55 2.09 1.98 3.83 4.03 4.87 C.V% 9.9 21.6 38.8 38.0 26.9 24.9 37.9 23.3 14.7 66.7 18.1 10.3 7.3 3.6 Legend: Data = Mean ± SEm, n=3. Showing also the maximum and minimum values for each of the morphological indices measured. SEm = standard error of the mean; S.D = standard deviation; C.V = coefficient of variation. 32 John Olayinka Atoyebi et al.: Morphological Characterisation of Selected African Accessions of Bambara Groundnut (Vigna subterranea (L.) Verdc.) Correlation Matrix Table 2. Linear relationships among fourteen morrphological parameters by correlation values DTE PL NFP NL TLL TLW PETL PS PH NC In DTF DFPF DM DTE DTE 1.000 0.004 -.0953 0.024 -.0621 -.0866 -.0600 -.0893 -.0052 -.1085 -.0092 0.002 0.041 -.0179 0 7 1 1 1 PL PL 0.004 1.000 0.221 0.240 0.217 0.373 -.0027 0.261 0.620 0.135 0.512 0.295 0.199 -.0737 7 0 1 3 7 7 4 8 8 8 2 0 NFP NFP -.0953 0.221 1.000 0.227 0.241 0.225 0.151 0.188 0.196 0.601 0.113 0.058 0.067 -.1547 1 0 1 7 4 4 3 6 1 1 5 5 NL NL 0.024 0.240 0.227 1.000 -.0901 -.0566 -.1187 0.138 0.145 0.147 0.200 0.350 0.366 -.3145 1 3 1 0 2 7 5 9 2 4 TLL TLL -.0621 0.217 0.241 -.0901 1.000 0.688 0.575 0.138 0.165 0.111 0.098 -.1136 -.0729 -.0371 7 7 0 6 3 0 0 7 4 TLW TLW -.0866 0.373 0.225 -.0566 0.688 1.000 0.360 0.231 0.352 0.111 0.157 -.0692 -.0797 -.0293 7 4 6 0 9 5 8 9 4 PET PET L L 0.151 -.0600 -.0027 0.360 1.000 0.111 0.144 0.155 -.0814 -.1624 -.0570 0.151 4 9 0 7 3 0 3 PS PS -.0893 0.261 0.188 0.138 0.138 0.231 0.111 1.000 0.319 0.135 0.160 -.0737 -.1237 -.0899 4 3 2 0 5 7 0 7 1 4 PH PH -.0052 0.620 0.196 0.145 0.165 0.352 0.144 0.319 1.000 0.161 0.356 0.137 0.107 0.085 8 6 7 0 8 3 7 0 8 3 4 9 1 NC NC -.1085 0.135 0.601 0.147 0.111 0.111 0.155 0.135 0.161 1.000 0.064 0.086 0.113 0.007 8 1 5 7 9 0 1 8 0 5 6 1 0 In In -.0092 0.512 0.113 0.200 0.098 0.157 -.0814 0.160 0.356 0.064 1.000 0.253 0.268 -.1234 8 1 9 4 4 4 3 5 0 6 5 DTF DTF 0.002 0.295 0.058 0.350 -.1136 -.0692 -.1624 -.0737 0.137 0.086 0.253 1.000 0.587 -.1911 1 2 5 2 4 6 6 0 8 DFP F DFP F 0.041 0.199 0.067 0.366 -.0729 -.0797 -.0570 -.1237 0.107 0.113 0.268 0.587 1.000 -.2151 1 0 5 4 9 1 5 8 0 DM DM -.0179 -.0737 -.1547 -.3145 -.0371 -.0293 0.151 -.0899 0.085 0.007 -.1234 -.1911 -.2151 1.000 3 1 0 0 International Journal of Plant Research 2017, 7(2): 29-35 33 List of abbreviations of the fourteen selected morphological parameters DTE - Days to emergence PL - Peduncle length NFP - Number of flowers per peduncle NL - Number of leaves TLL - Terminal leaf length TLW - Terminal leaf width PETL - Petiole length PS - Plant spread PH - Plant height NC - Nodulation capacity IN - Internode length DTF - Number of days to flowering DFPF - Number of days to 50% flowering DM - Days to maturity Table 3. List of African countries of Bambara groundnut collection S/N Countries of origin 1 Nigeria 2 Burkina Faso 3 Cote d’Ivoire 4 Benin republic 5 Gambia 6 Cameroon 7 Zambia 8 Zimbabwe 9 Central Africa Republic (CAR) 10 Botswana 11 Congo, Democratic Republic 12 Burundi TOTAL = Total 65 27 3 8 4 71 70 36 12 1 1 2 300 Figure 3. Showing the Principal Component Plot for selected fourteen Figure 4. Cluster analysis revealed as dendrogram for 300 Bambara parametric indices groundnut accessions 34 John Olayinka Atoyebi et al.: Morphological Characterisation of Selected African Accessions of Bambara Groundnut (Vigna subterranea (L.) Verdc.) 4. Conclusions International Union of Nutrition Society (IUNS), congress at Granada, Spain, September, 15th – 20th, 2013. Bambara groundnut (Vigna subterranea (L.) Verdc.) has a large number of landraces throughout Africa where small-scale farmers have preserved its genetic diversity on-farm. To date, the full genetic diversity of the crop [3] O.J. Atoyebi, J.O Faluyi, and O.O. Oyedapo. Investigation of the Genetic Diversity of selected wild and cultivated sorghum germplasm using SDS – PAGE. (M.Sc thesis). Greeners journal of biological sciences; vol. 4(1) pp 001 – 008. Feb. remains largely unexploited [5, 21, 24]. Also there has 2014. being little work on its breeding for improved Bambara groundnut varieties at the moment, infact none presently in Nigeria. However, with the results of this work, which [4] O.J. Atoyebi, O.O. Adebawo, O. Osilesi and E.B. Esan. Towards Biofortification of Bambara groundnut (Vigna subterranea) in Nigeria to combat hidden hunger. further states the importance of the crop as revealed by genetic and agro – morphological descriptors in the study, it Presentation at the Biotechnology Society of Nigeria (BSN) conference, Abuja, Nigeria. August, 26 – 30, 2013. serves to form a basis for selection in agricultural [5] S.N. Azam – Ali, A. Sesay, S.K. Karikari, and F.J. Massawe. improvement programs and nutrition studies in Bambara Assessing the potential of an under-utilised crop – a case groundnut. The selected 300 African accessions in this study / research work showed immense benefit of the crop study using bambara groundnut. Experimental agriculture 37: 433 – 472, 2001. for a developing country like Nigeria specifically and [6] Badu – Apraku, A. Menkir, M.A.B. Fakorede, A. Fontem Africa at large. The collected accessions exploited indicated Lum and K. Obeng -Antwi. Multivariate analysis of the potentials in terms of seed yield for TVSu – 293 (Bukina – faso); TVSu – 395 (Cameroon) and TVSu – 1243 (Nigeria). Also, TVSu – 397 (Cameroon) and TVSu – 1168 (Bukina – Genetic Diversity of forty-seven striga resistant tropical early maturing maize inbredlines. Maydica 51: 553 – 559, 2006. faso) has the highest number of leaves, while TVSu – 520 [7] S.M. Basu, S. Mayes, M. Davey, J.A. Roberts, S.N. Azam – (Cameroon) and TVSu – 1022 (Zimbabwe) gave the least. The least number of seeds was given by TVSu – 1 (Nigeria), TVSu – 353 (Nigeria) and TVSu – 454 (Cameroon); while Ali, R. Mithe, and R.S. Pasquet. Inheritance of domestication traits in Bambara groundnut (Vigna subterranea) L. verdc. Euphytica 157: 59 – 68, 2007. TVSu – 395 (Cameroon), TVSu – 618 (Nigeria) and TVSu – 1897 (Botswana) has the highest number of pods and seeds. The results of this study agrees with the findings of [12] that despite the numerous potentials in the crop, there is however a need to improve upon its utilisation and [8] Bode Olukolu, Sean Mayes, Florian Stadler, N. Quat Ng, Ijiwole Fawole, Dumet Dominique, Sayed N. Azam – Ali, Albert G. Abbott, Chittaranjan Kole. Genetic diversity in Bambara groundnut (Vigna subterranea (l.) verdc.) as revealed by phenotypic descriptors and DArT marker analysis. Genet Resour Crop Evol, 59: 347 – 358, 2012. market potentials, especially in developing countries of Africa, like Nigeria. [9] Catherine Ross., Benjamin Caballero, Robert J. Cousins et. al., Modern Nutrition in Health and Disease (11th edition), 2013. ACKNOWLEDGEMENTS The authors like to express acknowledgements to the International Institute of Tropical Agriculture, IITA, Ibadan, for the Graduate fellowship to conduct my PhD research. Also to the entire Genetic Resources Centre (GRC) staff of IITA, Ibadan, Nigeria; and those of Crops for the Future Research Centre (CFFRC), Semenyil, Malaysia campus, especially Dr. Sean Mayes and Dr. Aryo Feldman, for the support of this aspect of my PhD research. [10] Descriptors for Bambara groundnut (Vigna subterranea) L. verdc. (IPGRI, BAMNET, publication, 2000). [11] Emendu, Nnamdi B. and Emendu, Ebele Rita. Proximate Analysis, Characterisation and Utilization of Bambara Nut Oil (Mmanu – Okpa). International Journal of Scientific and Research Publications, Vol. 4, Issue 9, September 2014. [12] R.J. Hillocks, C. Bennett, and O.M. Mponda. Bambara nut: A review of utilization, market potential and crop improvement. African Crop Science Journal, vol. 20, no 1 pp 1 – 16 2012. REFERENCES [1] K. Adeoti, A. Dansi, L., Ahoton, R. Vodouhe, B.C. Ahohuendo, A. Rival, and A. Sanni, Agro-morphological characterisation of Sesamum radiatum (Schum. and Thonn.), a neglected and underutilised species of traditional leafy vegetable of great importance in Benin. African journal of Agric Research, vol. 7(24), pp 3569 – 3578; June, 2012. [2] O.J. Atoyebi, and E.B. Esan. Bambara groundnut (Vigna subterranea) as a panacea for malnutrition in developing countries like Nigeria. Poster presentation at the 20th [13] Kakol Ghosh. Human Immunodeficiency virus therapeutics and pharmacogenomics. Indian Journal of human Genetics. Vol. 17, issue 4, pp 22 -26, 2011. [14] S.N. Padulosi, Bergamini and T. 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[17] Sobda Gonne, Wassouo Felix – Alain and Koubala Bargui Benoit. Assessment of twenty Bambara groundnut (Vigna subterranea) L. verdc. Landraces using quantitative morphological traits. International journal of plant research, vol. 3 (3): pp 39 – 45, (2013). [21] D.J. Wigglesworth. The potential for genetic improvement of Bambara groundnut (Vigna subterranea L. Verdc.) in Botswana. Proceedings of the International Symposium on Bambara groundnut. University of Nottingham, UK 23-25 July, 1996, pp 181-191. [18] Statistical analysis software (SAS) package, version 9.3 (1999). [19] B. Tanimu and L. Aliyu. Northern Nigeria. Proceedings of the Workshop on Conservation and Improvement of Bambara Groundnut (Vigna subterranea (L.) Verdc.), Harare, Zimbabwe. Institute of Plant Genetics and Crop Plant Research, Gatersleben, Department of Research & Specialist Services, Harare and International Plant Genetic Resources Institute, Rome, Italy, 14–16 November 1995. [22] Yao. Product release is rate limiting in the activation of the prodrug 5-fluorocytosine by the yeast cytosine deaminase. Biochemistry 44 (15): 5940 -5947, 2015. [23] A.C Zeven. Landraces: A review of definitions and classifications. Euphytica 104: 127-139. 1998. [24] E.D. Zulu (1989). Germination and early seedling growth of Bambara groundnut in response to temperature, sowing depth and soil water. MSc thesis, Nottingham University, UK.

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