Sphenostylis Stenocarpa (Ex

Article Sphenostylis stenocarpa (ex. A. Rich.) Harms., a Fading Genetic Resource in a Changing Climate: Prerequisite for Conservation and Sustainability

Catherine Veronica Nnamani 1,*, Sunday Adesola Ajayi 2, Happiness Ogba Oselebe 3, Christopher John Atkinson 4, Anastasia Ngozi Igboabuchi 5 and Eucharia Chizoba Ezigbo 1

1 Plant Taxonomy/Biosystematics and Conservation Biology Research Lab, Department of Applied Biology, Ebonyi State University, Abakaliki 840001, Nigeria; [email protected] 2 Department of Crop Production and Protection, Obafemi Awolowo University, Ile-Ife 220282, Nigeria; [email protected] 3 Department of Crop Production & Landscape Management, Ebonyi State University, Abakaliki 840001, Nigeria; [email protected] 4 Natural Resources Institute, University of Greenwich, Medway Campus, Central Avenue, Chatham Maritime, Kent ME4 4TB, UK; [email protected] 5 Department of Biology, Nwafor Orizu College of Education, Nsugbe 240001, Nigeria; [email protected] * Correspondence: [email protected] or [email protected]; Tel.: +234-803-778-6269

Received: 1 May 2017; Accepted: 7 July 2017; Published: 12 July 2017

Abstract: The southeastern part of Nigeria is one of the major hotspots of useful plant genetic resources. These endemic species are associated with a rich indigenous knowledge and cultural diversity in relation to their use and conservation. Sphenostylis stenocarpa (ex. A. Rich.) Harms., (African Yam Bean (AYB)), is one such crop within the family of Fabaceae. Its nutritional and eco-friendly characteristics have value in ameliorating malnutrition, hidden hunger and environmental degradation inherent in resource-poor rural and semi-rural communities throughout Africa. However, lack of information from the custodians of this crop is limiting its sustainable development. Therefore, ethnobotanical surveys on the diversity, uses, and constraints limiting the cultivation and use of the crop in southeastern Nigeria were carried out. Five-hundred respondents were randomly selected and data collected through oral interviews and focused group discussion (FGD). Semi-structured questionnaires (SSQ) were also used to elicit information from a spectrum of AYB users comprising community leaders, farmers, market women and consumers in five States. Results showed that the majority of the respondents lacked formal education and were of the age group of 40–50 years, while the female gender dominated with limited access to land and extension officers. Seed coat colour largely determined utilization. Long cooking time, requirement for staking materials, aging of farmers and low market demand were among the major constraints limiting further cultivation and utilization of AYB. In-situ conservation was by hanging dried fruits by the fireside, beside the house, storing in earthenware, calabash gourds, cans and bottles. It is concluded that there is urgent need to scale up conservation through robust linkages between contemporary scientific domains and indigenous peoples in order to harness and incorporate the rich indigenous knowledge in local communities for enhanced scientific knowledge, biodiversity conservation and its sustainable utilization for food security.

Keywords: African Yam Bean; indigenous knowledge; genetic erosion; conservation; food security; Nigeria

Plants 2017, 6, 30; doi:10.3390/plants6030030 www.mdpi.com/journal/plants Plants 2017, 6, 30 2 of 17

1. Introduction The dependence of humans on plants for their livelihood is connected to the development of specific knowledge on plant value, use, management, and conservation [1,2]. The Convention on Biological Diversity [3] stresses the need to respect, preserve and maintain the knowledge, innovation and practices of indigenous communities relevant for the conservation and sustainable use of biological diversity. The direct relationship between biological and cultural diversity shows that the maintenance of the former can help preserve the latter while increasing the capacity of human to adapt to change [4]. Just as biological diversity underpins the resilience of natural systems, so does cultural diversity [5] and this increases the resilience of social systems. Indigenous people are the major custodians of knowledge on endemic biodiversity because of the long and intertwined associations between their survival and the utilization of plant species for food, traditional medicine and a diversity of other uses. Harnessing this information can strengthen research in the contemporary scientific domain on AYB. Ethnobotanical information is essential for assessing both the diversity and the adaptation characteristics of useful plants and this helps in understanding a plants’ micro-niches and the stability of environmental conditions. It is also useful in the collection of the genetic resources of these cultivated and economically important species in order to capture variation within these species [6]. Ethnobotany serves as an untapped reservoir of knowledge, especially with respect to the interactions between plants, people, folk taxonomy, plant mythology, ethnomedicine, food security, environment restoration and germplasm conservation. Unfortunately, the indigenous knowledge systems are fast eroding due to several anthropogenic factors such as colonialism, commercialization, globalization, modernization, breakdown of the African traditional family structures, developmentally-induced human displacements and urban migration, all of which have induced a lack of interest from the younger generation [7]. Nigeria is one of the hotspots for plants genetic resources and cultural diversity [8,9]. Hence, the various geographical zones provide a platform for the study of perceptions of the custodians of indigenous knowledge about plant genetic resources. Sphenostylis stenocarpa (ex. A. Rich.) Harms, commonly known as African yam bean (AYB), is a neglected and underutilized leguminous plant genetic resource of the subfamily Faboideae, family Fabaceae and a small genus represented by only seven species [10]. It is a perennial climbing species whose morphotypes may also be prostrate, or erect and about 1–3 m in height. Its leaves are trifoliate, 2.7 to 13 cm long and 0.2 to 5.5 cm broad. The inflorescence is a raceme that exhibits an acropetal mode of floral maturation with pink flowers blended with purple, with the slightly twisted backward characteristic of the Fabaceae [11]. The center of diversity of AYB is the northeast tropical Africa (Chad and Ethiopia), east tropical Africa (Kenya, Tanzania and Uganda), west-central tropical Africa (Burundi, Central African Republic and Zaire), West Africa (Cote d’Ivoire, Ghana, Guinea, Mali, Niger, Nigeria and Togo) and south tropical Africa (Angola, Malawi, Zambia and Zimbabwe) [12,13]. African yam bean is cultivated for its edible tubers and for its seeds which have high nutritional values. The amino acid (lysine and methionine) has been reported to be higher than those of pigeon pea, cowpea, and bambara groundnut [14]. Omeire [15], noted that the amino acid (g/100 g) profile of African yam bean comprised lysine (6.12), histidine (3.10), arginine (6.47), aspartic acid (9.12), glycine (3.90), alanine (4.05), valine (4.96), and phenylalanine (5.05). Its lysine and methionine contents were equal to or better than those of soybean protein [16], while equally comparable with whole chicken eggs and can meet the daily human requirement for protein [17]. Its protein profile compares favourably with that of other African root crops such as yams, sweet potatoes and has almost ten times the protein value of cassava tubers, while the essential proteins in AYB are similar to those in soybeans [18]. In spite of the extensive information on the morphological characterization for yield [11,13,19,20], biochemical profiles [21–23], physiological seed quality [24], and genetic diversity [25–28] of AYB, there is dearth of information on ethnobotanical knowledge on this highly-promising plant genetic resource. Therefore, the aim of this study was to carry out an ethnobotanical survey to develop a hub of indigenous knowledge on AYB and to complement this with the existing wealth of scientific knowledge. Plants 2017, 6, 30 3 of 17

Therefore, the aim of this study was to carry out an ethnobotanical survey to develop a hub of indigenous knowledge on AYB and to complement this with the existing wealth of scientific Plants 2017, 6, 30 3 of 17 knowledge. This study sought to systematically bridge the knowledge gap by (a) identifying the socio-economic characteristics of respondents involved in AYB activities in five states of Thissoutheastern study sought Nigeria; to systematically (b) determine bridgethe uses the of knowledge AYB and phenotypic gap by (a) identifying variability thein seed socio-economic coat colour characteristicsand (c) identify of those respondents constraints involved limiting in the AYB use activities and production in five states systems of southeastern of AYB in southeastern Nigeria; (b) determineNigeria. the uses of AYB and phenotypic variability in seed coat colour and (c) identify those constraints limiting the use and production systems of AYB in southeastern Nigeria. 2. Results and Discussion 2. Results and Discussion 2.1. Social Background of Respondents 2.1. Social Background of Respondents Two-hundred-fifty-six (51.2%) of the 500 respondents were 50 years old and were involved eitherTwo-hundred-fifty-six in the cultivation and/or (51.2%) sales of of the AYB 500 respondentsproducts as a were source 50 yearsof food old and and income. were involved Two percent either in(2%), the 2.5% cultivation and 6.8% and/or of salesthe respondents of AYB products were as wi athin source the of age food limits and income.of <19, Two20–29 percent and 30–39, (2%), 2.5%respectively and 6.8% (Figure of the 1). respondents With respect were to withinthe level the of age education limits of 37.2% <19, 20–29 had andprimary 30–39, school-leaving respectively (Figurecertificates1). With while respect 34% tohad the no level formal of education education 37.2% (Figure had primary2). These school-leaving results are similar certificates to those while of 34%Mathibela had noet formalal. [29], education who reported (Figure that2). These64% of results traditiona are similarl healers, to thosewho ofwere Mathibela the custodians et al. [ 29 of], whoindigenous reported knowledge that 64% ofin traditional medicinal healers,plants in who the were Blouberg the custodians area of South of indigenous Africa, had knowledge no formal in medicinaleducation, plants while in 32% the Blouberghad primary area ofschool South certific Africa,ates, had nowith formal only education, 4% having while attended 32% had secondary primary schoolschool. certificates,The implications with only of these 4% having results attended are that secondarypotentially school.valuable The information implications on of these these plants results is arein the that hands potentially of the valuableolder generati informationon who on by these virtue plants of their is in theage hands have ofa diminishing the older generation involvement who byin virtueAYB cultivation. of their age Their have educational a diminishing levels involvement may not limit in AYB them cultivation. from documenting Their educational this knowledge levels may for notposterity limit themand for from the documenting benefit of people this knowledgeoutside the forlocal posterity community. and forWith the the benefit very oflow people involvement outside theof younger local community. people in farming With the in very general low and involvement specifically of in younger the cultivation people inof farmingAYB, it is in reasonable general and to specificallyassume that in there the cultivation will be a progressive of AYB, it is decline reasonable and toeventually assume that a substantial there will beloss a progressiveof indigenous decline AYB andcultural eventually knowledge a substantial and genetic loss diversity of indigenous over tempor AYB culturalal and knowledgespatial scales. and This genetic is in diversity line with over the temporalopinion of and Dania-Ogbe spatial scales. et Thisal. is[30], in linewho with suggested the opinion that of the Dania-Ogbe most significant et al. [30 ],global who suggestedthreat to thatbiodiversity the most significantis the erosion global of threat ethnobotanical to biodiversity knowledge is the erosion caused of ethnobotanical by the demise knowledge of the causedaging bycustodians the demise of this of theknowledge. aging custodians This situation of this is knowledge.worsened by This the situationweak linkages is worsened between by domain the weak of linkagesscience and between indigenous domain knowledge of science [31]. and indigenous knowledge [31].

300 256 250 186 200 150 100 34 50 10 14 0

Figure 1. Age range of respondents from the ﬁvefive states of southeastern, Nigeria.Nigeria. Plants 2017, 6, 30 4 of 17 Plants 2017, 6, 30 4 of 17

Plants 2017, 6, 30 4 of 17

34% 37% First Sch. Cert WAEC

34% BSc 0% 37% First Sch. Cert 9% MSC 4% 16% WAEC PhD BSc 0% 9% No Edu 4% 16% MSC PhD

Figure 2. Educational background status of respondents fromNo the Edu five states of South eastern, Nigeria. Figure 2. Educational background status of respondents from the ﬁve states of South eastern, Nigeria. 2.2. Gender and Marital Status of Respondents 2.2. Gender and Marital Status of Respondents FigureA gender 2. Educational disaggregation background of statusthe respondents of respondents in fr thisom thestudy five showedstates of Souththat theeastern, ratio Nigeria. of female to Amale gender involvement disaggregation in the cultivation of the respondents of and transactions in this study of AYB showed was approximately that the ratio of2:1, female 61.6% toto male 2.2. Gender and Marital Status of Respondents involvement34.8%. A inhigher the proportion cultivation (74.3%) of and of transactions the respondents of AYBinvolved was in approximately AYB cultivation 2:1, and 61.6% processing to 34.8%. A higherwereA genderproportionmarried disaggregation women (74.3%) while of of the the the proportions respondentsrespondents of in involvedsi thisngle studyindividuals, in showed AYB cultivationwidows that the and ratio and widowers of processingfemale were, to were marriedmalerespectively, involvement women while0.7%, in thethe19.2%, proportionscultivation and 5.8% of of and(Figure single transactions individuals,3). The ofdominance AYB widows was ofapproximately and the widowers female gender2:1, were, 61.6% in respectively, AYBto 0.7%,34.8%.cultivation 19.2%, A higher and and proportion 5.8%indigenous (Figure (74.3%) knowledge3). Theof the is dominance respon not uniquedents to ofinvolved Nigeria, the female in as AYB similar gender cultivation findings in AYB andwere processing cultivation reported for and werethe marriedBaka tribe women in Cameroon while the[32] proportionsand the Masai of insi ngleKenya individuals, [33] for knowledge widows associatedand widowers with thewere, sales indigenous knowledge is not unique to Nigeria, as similar ﬁndings were reported for the Baka tribe in respectively,of indigenous 0.7%, plants. 19.2%, The andresults 5.8% are (Figurealso in agreement3). The dominance with the report of the by femaleYahaya gender[34] who in reported AYB Cameroon [32] and the Masai in Kenya [33] for knowledge associated with the sales of indigenous cultivationthat 77.9% and of indigenousmarried smallholder knowledge farmers is not unique compared to Nigeria, to 22.1% as singlesimilar women findings were were involved reported in for rice plants.thefarming Baka The tribe resultsin inAwe Cameroonare Local also Government [32] inagreement and the AreaMasai with of in NasarawaKenya the report [33] Statefor by knowledge Yahayain Nigeria.[ associated34 The] who high reported with proportion the sales that of 77.9% of marriedof femaleindigenous smallholdergender plants. was viewedThe farmers results by one comparedare ofalso the in respondents agreement to 22.1% singlewith as follows: the women report “Africa by were YahayaYam involved Bean [34] is regardedwho in ricereported as farming minor in Awethatand Local 77.9% women’s Government of married crop; not smallholder worthy Area ofto engage Nasarawa farmers the energycompared State and in laboursto Nigeria. 22.1% of thesingle The men. highwomen They proportion have were the involved patience/endurance of female in rice gender wasfarming viewedof its rigorous inby Awe one attentions Local of the Government an respondentsd hard-to-maintain Area as follows:of practices Nasarawa “”.Africa AYB State also Yam in servesNigeria. Bean isas regardedaThe supplementary high as proportion minor source and of women’s of crop;female notincome worthy gender for female to was engage viewed farmers. the by energy Theone culturalof and the labours respondents characterist of the as men.ics follows: of Theythe study “ haveAfrica area, the Yam patience/endurance where Bean isthere regarded is often as ofminor a its wide rigorous attentionsandage women’s gap and between hard-to-maintaincrop; not partners, worthy to isengage practices exacerbated the”. energy AYB by and the also labours fact serves that of thethe as men. amajority supplementary They haveof the the respondents patience/endurance source of lived income in for femaleof itsrural farmers.rigorous areas. attentions This The provides cultural and hard-to-maintain some characteristics reasoning practices for of the the”. dominance AYB study also area, serves of wherewomen as a theresupplementaryupon whose is often shoulders asource wide of agethe gap incomeresponsibility for female of farmers. meeting The household cultural characterist food requicsirements of the study usually area, fallswhere after there their is often older a wide male between partners, is exacerbated by the fact that the majority of the respondents lived in rural areas. agecounterparts gap between are partners, no longer is ableexacerbated to undertake by the manual fact that labour. the majority of the respondents lived in Thisrural provides areas. This some provides reasoning some for reasoning the dominance for the dominance of women of upon women whose upon shoulders whose shoulders the responsibility the of meetingresponsibility household of meeting food requirementshousehold food usually requ fallsirements after theirusually older falls male after counterparts their older aremale no longer Widower , Gender, 0 ablecounterparts to undertake are manualno longer labour. able to undertake5.8 manual labour.

Widow , Widower , 19.2 Gender,Male 0 , 38.4 5.8 , 0 Widow , 19.2 Male , 38.4 Married , , 0 74.3 Female , 61.6

Married , 74.3 Female , 61.6 Marital Single , 0.7 , 0 status, 0

Figure 3. Gender and marital status of respondents. Marital Single , 0.7 , 0 status, 0

Figure 3. Gender and marital status of respondents. Figure 3. Gender and marital status of respondents. Plants 2017, 6, 30 5 of 17 Plants 2017, 6, 30 5 of 17

2.3. Visit of Extension Ofﬁcers,Officers, SizeSize ofof FarmFarm LandLand andand SourcesSources ofof IncomeIncome The majority (68%) of thethe respondentsrespondents did notnot receivereceive informationinformation or adviceadvice fromfrom extensionextension ofﬁcersofficers whilewhile 32%32% claimedclaimed to have hadhad contact with them. Similarly, 11%, 43%, 34% and 12% of thethe respondents normally receive social grantsgrants fromfrom aa farmers’farmers’ council,council, aa ChristianChristian organization,organization, ageage grade or a cooperativecooperative society, respectivelyrespectively (Figure(Figure4 4).). AremuAremu etet al.al. [ [35],35], notednoted thatthat thethe knowledgeknowledge and application of extension education principles helped extension workers to determine farmers’ needs, constraints, priorities andand opportunities connectedconnected toto theirtheir farmingfarming activities.activities. They concluded thatthat itit alsoalso gavegave themthem thethe opportunityopportunity to teach farmersfarmers the value of improved agricultural practices; recommending suitable crops for differentdifferent agro-ecologicalagro-ecological zones andand encouragingencouraging the adoptionadoption ofof appropriate technologies.technologies. The The low low level level of farmer-extension of farmer-extension contacts contacts in this studyin this could study be implicatedcould be asimplicated a majorcontributory as a major contributory factor to AYB fact beingor to anAYB underutilized being an underutilized crop. crop.

70 60 50 40 30 20 10 0

Figure 4.4. Extension officer’s ofﬁcer’s visits, size size of farmland and source of help for farming activities for respondentsrespondents inin thethe ﬁvefive statesstates ofof southeastern,southeastern, Nigeria.Nigeria.

The result also indicated that 41.6% of the respondents had a farm size of less than 0.25–1.50 The result also indicated that 41.6% of the respondents had a farm size of less than hectares, 35.9% had between 1.51–2.43 hectares while 18.3% had about 2.2–3.22 hectares (Figure 4). 0.25–1.50 hectares, 35.9% had between 1.51–2.43 hectares while 18.3% had about 2.2–3.22 hectares Only 1.9% had a farm size that was more than four hectares. These observations are in agreement (Figure4). Only 1.9% had a farm size that was more than four hectares. These observations are with the findings of Nze and Eboh [36] who reported that 70% of respondents in the three in agreement with the ﬁndings of Nze and Eboh [36] who reported that 70% of respondents in the agricultural zones of Enugu State had access to ≤3 ha farm land. This could also be attributed to the three agricultural zones of Enugu State had access to ≤3 ha farm land. This could also be attributed land tenure system of ownership where women do not have access to land ownership in to the land tenure system of ownership where women do not have access to land ownership in southeastern Nigeria. southeastern Nigeria. Famoriyo [37] noted that under the customary rules of land tenure, each individual member of Famoriyo [37] noted that under the customary rules of land tenure, each individual member a landholding family was entitled to a portion of land, enough to feed himself and the members of of a landholding family was entitled to a portion of land, enough to feed himself and the members ‘his family’, suggesting that men owned land and they apportion it as deemed fit to women. On the of ‘his family’, suggesting that men owned land and they apportion it as deemed ﬁt to women. contrary, in the study with the Amawbia community in Awka South L.G.A. of Anambra State, On the contrary, in the study with the Amawbia community in Awka South L.G.A. of Anambra State, Osita [38] noted that farmland allocated to women for cultivation was to keep them busy and to Osita [38] noted that farmland allocated to women for cultivation was to keep them busy and to enable enable them to feed their households from their farm products, and to enable them to cushion the them to feed their households from their farm products, and to enable them to cushion the effects of effects of poverty and food insecurity. poverty and food insecurity. 2.4. Local Nomenclature of African Yam Bean In southeastern Nigeria, AYB goes by a multiplicity of names based on locality and dialect. At Ngwu Uzuakoli community in Bende LGA of Abia State, AYB is called “Odudu” while in Umuahia Plants 2017, 6, 30 6 of 17

Plants 2017, 6, 30 6 of 17 2.4. Local Nomenclature of African Yam Bean NorthIn Local southeastern Government Nigeria, Area AYBin Abia goes State by it a is multiplicity known as “Akidi”. of names However, based on in locality Anambra and and dialect. Imo AtStates, Ngwu it is Uzuakoli known communityas “Okpodudu” in Bende while LGA in Enugu of Abia State, State, there AYB isare called an array “Odudu” of local while names in Umuahia among Northmany towns. Local Government It is known Areaas “Uzoaki” in Abia in State Awgu, it is knownAninri, asNkanu “Akidi”. North However, and East in Local Anambra Government and Imo States,Areas while it is known in Nsukka, as “Okpodudu” Udeni, Igboeze while South in Enugu Igbo State,eze North, there and are anIgbo-Etiti array of South local namesAYB is among called many“Ijiriji”. towns. Extending It is knowntowards as the “Uzoaki” southern in Awgu,part of Aninri,southeast, Nkanu Nigeria, North to and Ebonyi East State, Local GovernmentAfrican yam Areasbean is while called in “Uzoaki” Nsukka, in Udeni, Afikpo Igboeze and Ohaozara South Igboeze areas while North, in Izzi, and Ikwo Igbo-Etiti and Ohaukwu South AYB LGAs is called it is “Ijiriji”.known as Extending “Azama”. towards These themultiplicities southern part of names of southeast, were based Nigeria, on tothe Ebonyi status State, and or African position yam of bean this iscrop called in the “Uzoaki” trado-cultural in Aﬁkpo settings and Ohaozara of some areas of the while local in communities. Izzi, Ikwo and It Ohaukwu is a food LGAsprepared it is knownfor the aslabourers “Azama”. when These they multiplicities are hired toof work names on werefarm. based They oneat the the status food andin the or morning position ofand this will crop keep in theon trado-culturaldrinking water settings without of getting some of famished the local for communities. a very long Ittime. is a foodIn an preparedidiomatic for way, the they labourers refer to when the theycrop areas ‘6 hired to 6’, to meaning work on that farm. when They you eat eat the AYB food by in 6 the am, morning while working, and will you keep will on drinkingnot need waterto eat withoutagain till getting 6 pm. famishedAYB is also for a a crop very that long sustains time. In the an idiomaticpeople when way, other they refercrops to are the scarce crop asor ‘6are to all 6’, meaningcultivated that on whenthe farm. you eat AYB by 6 am, while working, you will not need to eat again till 6 pm. AYB is also a crop that sustains the people when other crops are scarce or are all cultivated on the farm. 2.5. Diversity in Seed Coat Colour and Pattern of the AYB Accessions Collected from Southeastern Nigeria 2.5. DiversityA wide invariation Seed Coat in Colourseed coat and Patterncolours of and the AYBpatterns Accessions in AYB Collected accessions from Southeasternwas observed Nigeria in this study.A wideThe existence variation inof seedthis coatnatural colours variation and patterns across in these AYB accessionsaccessions wasis very observed obvious. in this Colour study. Thevariation existence ranges of thisfrom natural very light variation brown across to completely these accessions black, variegated is very obvious. brown Colour with black variation shading ranges to fromblack veryvariegated. light brown Others to completelywere milky black, with variegatedblack eye; brownmilky with blackbrown shading eye and to black variegated.(Figure 5). OthersThese variations were milky could with prove black eye;to be milky useful with to both brown farmers eye and and black conservation (Figure5). biologists These variations in providing could provesimple to identification be useful to bothof genetic farmers variation, and conservation its storage biologists and future in providing development simple within identiﬁcation potential of geneticbreeding variation, programmes. its storage and future development within potential breeding programmes.

Figure 5. Diversity in seed coat colours and patternspatterns inin SphenostylisSphenostylis stenocarpa (ex. A. Rich.) Harms. Harms. (African yam bean)bean) accessionsaccessions fromfrom ﬁvefive statesstates inin southeast,southeast, Nigeria.Nigeria. PhotoPhoto byby Nnamani.Nnamani.

FAO [[39]39] noted that traditional varieties have higher stability to adapt to to climate climate variability, variability, change and low-input agriculture under marginal environmentsenvironments thereby facilitating a higher level of resilience forfor farmers farmers in in facing facing food food production production risks. risks. This diversityThis diversity is paramount is paramount for varietal for breedingvarietal asbreeding noted byas noted [40]. Theyby [40]. concluded They concluded that when that breeders when needbreeders to develop need to newdevelop crops new with crops desirable with characteristicsdesirable characteristics such as yield such potential, as yield greaterpotential, seed greater quality, seed pest quality, and disease pest and resistance, disease preferenceresistance, ispreference given the is species given withthe species diverse’ with genetic diverse’ traits, ge whichnetic traits, are of which immense are importanceof immense toimportance farmers and to conservationfarmers and conservation biologists. Seed biologists coat patterning. Seed coat also patterning appears also todetermine appears to the determine choice of the selection choice of seedsselection for of cultivation seeds for andcultivation cooking. and Although cooking. thereAlthough were there diverse were and diverse mixed and views mixed about views the about seed coatthe seed pattern, coat a pattern, higher percentagea higher percentage of the respondents of the respondents preferred the preferred variegated the blackvariegated and brown black seedand colourbrown toseed the colour milk andto the white milk seedsand white (Figure seeds5). This(Figure was 5). based This onwas their based assumption on their assumption that the black that andthe black brown and variegated brown variegated seeds were, seeds in their were, opinion, in their more opinion, proteinous more and proteinous yielded moreand yielded when grown. more Thiswhen is grown. in line withThis is the in report line with of Ikhajiagbe the report andof Ikhajiagbe Mensah [and41] Mensah who noted [41] thatwho the noted yield that of blackthe yield seeds of black seeds of AYB per hectare was significantly greater (1542 kg ha−1) compared to either the brown variant (1304 kg ha−1), or the milky variant (1259 kg ha−1). The wide range of diversity inherent in Plants 2017, 6, 30 7 of 17 of AYB per hectare was signiﬁcantly greater (1542 kg ha−1) compared to either the brown variant (1304Plants kg2017 ha, 6−, 301), or the milky variant (1259 kg ha−1). The wide range of diversity inherent in AYB7 of could 17 have contributed to the continuous availability of the crop despite a general level of neglect and limited AYB could have contributed to the continuous availability of the crop despite a general level of exploitation in Africa [13]. neglect and limited exploitation in Africa [13]. 2.6. Food Utilization of African Yam Bean 2.6. Food Utilization of African Yam Bean The corresponding multiple uses of AYB recorded in most of communities is a feature of the culturalThe diversity corresponding in these multiple agro-ecological uses of AYB zones. recorded The array in most of menus of communities for which AYB is a isfeature used forof the food cultural diversity in these agro-ecological zones. The array of menus for which AYB is used for food in southeastern Nigeria was wide for a homogenous, linguistically and culturally-knitted group of in southeastern Nigeria was wide for a homogenous, linguistically and culturally-knitted group of respondents. The majority of the respondents have good knowledge of this species as part of their respondents. The majority of the respondents have good knowledge of this species as part of their diet. However, the older informants (64.3%) were more knowledgeable in this than the younger ones diet. However, the older informants (64.3%) were more knowledgeable in this than the younger ones (23%) while 12.7% had no knowledge of other uses of AYB except as snack. This could be attributed to (23%) while 12.7% had no knowledge of other uses of AYB except as snack. This could be attributed preference of exotic foods to indigenous foods and lack of interest by younger generation. to preference of exotic foods to indigenous foods and lack of interest by younger generation. In Abia State, it is roasted and eaten as snack (Figure6a) or cooked as pottage, or mixed with In Abia State, it is roasted and eaten as snack (Figure 6a) or cooked as pottage, or mixed with “Ugba” (Pentaclethra macrophylla), “Okporoko” (stock ﬁsh) and served as delicacy at festive events such “Ugba” (Pentaclethra macrophylla), “Okporoko” (stock fish) and served as delicacy at festive events assuch traditional as traditional marriage, marriage, the new the yam new festival yam festival and burial and ceremoniesburial ceremonies (Figure (Figure6b). This 6b). is oneThis of isthe one most of cherishedthe most cherished foods given foods to a given visitor to ina visito somer communitiesin some communities of Abia State.of Abia State.

(a) (b) (c)(d)

(e) (f) (g)(h)

Figure 6. Diversity of foods prepared from Sphenostylis stenocarpa accessions in the five states of Figure 6. Diversity of foods prepared from Sphenostylis stenocarpa accessions in the ﬁve states of southeast Nigeria. (a–h): AYB in association with other crops eaten in southeast Nigeria. southeast Nigeria. (a–h): AYB in association with other crops eaten in southeast Nigeria. (a) Fried (a) Fried AYB and eating with palm kneel as a snack. (b) Food prepared from AYB with dried AYB and eating with palm kneel as a snack; (b) Food prepared from AYB with dried cock-yam and cock-yam and “Akpaka—oil-bean seed (Pentaclethra macrophylla). (c) AYB with Yam. (d) AYB cooked “Akpaka—oil-bean seed (Pentaclethra macrophylla); (c) AYB with Yam; (d) AYB cooked as pottage; as pottage. (e–f) AYB prepared as mio-mio cake called Ugbagidi in Agwu LGA in Enugu State. (e–f) AYB prepared as mio-mio cake called Ugbagidi in Agwu LGA in Enugu State; (g) AYB prepared (g) AYB prepared with ground maize (Ayaraya Oka) and Akpaka. (h) Researcher enjoying herself with ground maize (Ayaraya Oka) and Akpaka; (h) Researcher enjoying herself with the delicacy of with the delicacy of AYB at Ubani market in Abia State. Source: 2016 Field Survey. AYB at Ubani market in Abia State. Source: 2016 Field Survey. Photo © Nnamani. Photo © Nnamani.

AmongAmong thethe communitiescommunities in Anambra State State it it is is cooked cooked with with yam yam (Figure (Figure 6c–d)6c–d) and and served served as as pottagepottage or or made made intointo flourflour andand fried as balls. In In Ebonyi Ebonyi State State it it is is roasted roasted or or eaten eaten as as snack snack with with palm palm kernelkernel or or cooked cooked with with yam yam or asor thickener/condiment as thickener/condiment for soup.for soup. Respondents Respondents in Enugu in Enugu State reported State thatreported AYB isthat made AYB into is flourmade and into used flour to and prepare used moin-moin to prepare (Figuremoin-moin6e–f) (Figure or cooked 6e–f) as pottageor cooked mixed as withpottage vegetables, mixed withPentaclethra vegetables, macrophylla Pentaclethra, dried macrophylla fish (Figure, dried6d–h) fish and (Figure served 6d–h) as delicacy and served on festive as eventsdelicacy such on asfestive traditional events marriagesuch as traditional and naming marriage ceremonies. and naming It is also ceremonies. roasted and It is eaten also roasted as snack and with eaten as snack with soft palm kernel. It could be cooked with yam and served as pottage or made into flour and mixed with maize flour to prepare foo-foo, and served with “okra” (lady’s finger) soup. Plants 2017, 6, 30 8 of 17

Plants 2017, 6, 30 8 of 17 soft palm kernel. It could be cooked with yam and served as pottage or made into flour and mixed withThese maize flourobservations to prepare corroborate foo-foo, and with served the withreport “okra” by Naskashima (lady’s finger) et soup.al. [42] who noted that indigenousThese observationscommunities, corroborate in China, Bolivia with the and report Kenya, by favoured Naskashima the etcultivation al. [42] who of varieties noted that of traditionalindigenous crops communities, over a single in China, high-yielding Bolivia and but Kenya,also high-risk, favoured mono-cropping the cultivation system of varieties in rural of settings.traditional The crops discovery over a singleof these high-yielding diverse menus but in also wh high-risk,ich AYB is mono-cropping prominent in southeastern system in rural Nigeria settings. is Theconsistent discovery with of thesethe report diverse by menus [43] that in which AYB AYB in Ghana, is prominent is used in southeastern extensively Nigeriain various is consistent dietary withpreparations the report and by [this43] thathas AYBpotentially in Ghana, supplemente is used extensivelyd the protein in various requirements dietary preparations of many andfamilies this throughouthas potentially the supplementedyear. They observed the protein that the requirements maintenance of manyof diverse families traditional throughout crop the varieties year. They and accessobserved to thatseeds the were maintenance essential oftools diverse for traditionalthe adapta croption varietiesand survival and accessof poor to seedsrural werefarmers. essential This enablestools for thethem adaptation to conserve and survivalgermplasm of poor and rural provide farmers. a Thiscontingency enables themwhen to conserveconditions germplasm are not favourable.and provide a contingency when conditions are not favourable. However, it was observed from the respondents in these zones that they were not aware aware of of AYB AYB having tubers underground which they could equallyequally use.use.

2.7. Income Extractable from the Sales of AYB in the Five States of Southeastern Nigeria 2.7. Income Extractable from the Sales of AYB in the Five States of Southeastern Nigeria Figure 77 showsshows aa summarysummary ofof thethe averageaverage incomeincome generatedgenerated fromfrom thethe salessales ofof products,products, seedsseeds and thethe diversitydiversity of of menus menus derivable derivable from from AYB. AYB. The studyThe study showed showed that the that highest the highest income ofincome N16,000 of ($180N16,000 USD) ($180 was USD) generated, was generated, particularly particularly in Abia State,in Abia from State, the from sales the of sales prepared of prepared food of diversefood of diversemenus frommenus AYB, from sold AYB, in thesold open in the markets, open market and froms, and road from hawkers road hawkers (Figure7 ).(Figure The least 7). The income least wasincome recorded was recorded from Ebonyi from onEbonyi the sales on the of AYBsalesseeds of AYB and seeds other and food other menus. food Thus, menus. AYB Thus, provides AYB providesa good complementary a good complementary source of incomesource of for inco theme resource-poor for the resource-poor rural and semi–rural rural and dwellerssemi–rural in dwellerssoutheastern in southeastern Nigeria. This Nigeria. conﬁrms This the confirms opinion ofthe Legwaila opinion of et al.Legwaila [44] that et foodal. [44] security that food and security poverty andalleviation poverty in alleviation rural communities in rural cancommunities be improved can bybe diversifyingimproved by the diversifying existing few the staple existing crops few to stapleinclude crops underutilized to include plants. underutilized They concluded plants. They that concluded the few staple that cropsthe few exploited staple crops in dry exploited conditions in dryof Botswana conditions could of Botswana not improve could the not lives improve of resource-poor the lives of ruralresource-poor households rural without households incorporating without incorporatingalternatives such alternatives as indigenous such as food indigenous plants. food plants.

200 Seeds sold during planting 180 Seeds sold during harvest 160 Verity of cooked menu Seeds sold by traders 140

120

100

0 Abia Anambra Ebonyi Enugu Imo

Figure 7. Income extractable from the sales of AYB in the five states of southeastern Nigeria (USD). Figure 7. Income extractable from the sales of AYB in the ﬁve states of southeastern Nigeria (USD).

Furthermore, experience has shown that many African rural communities actually rely on indigenousFurthermore, plants for experience food security has shownand as thatsource many of cash African income rural between communities cropping actually seasons. rely It has on beenindigenous established plants that for food neglected security and and underutilized as source of cash species income in betweensoutheastern cropping Nigeria seasons. were It potential has been sourcesestablished of thathigh neglected levels of and essential underutilized nutrients species which in southeasterncontributed Nigeriato the weredaily potential requirement sources and of maintenance of good health of the resource-poor rural households. It has a direct impact on alleviating poverty, building a sustainable future for these people who are dependent on it as source of livelihood [45]. Plants 2017, 6, 30 9 of 17 high levels of essential nutrients which contributed to the daily requirement and maintenance of good health of the resource-poor rural households. It has a direct impact on alleviating poverty, building a sustainable future for these people who are dependent on it as source of livelihood [45].

2.8. Other Uses of African Yam Bean in the Five States of Southeastern Nigeria In all the states, AYB was utilized for many other livelihood services. Respondents enumerated situations where the integration of AYB was crucial for the wellbeing of the people as summarized in Table1. The ability of the indigenous communities to integrate and interact with their natural surroundings has been a positive approach in their resilience, survival and sustainable development. The utilitarian value of AYB in the communities examined spanned the ﬁve states studied. Such utilitarian value includes the use of dried AYB snacks by diabetic patients, extract of mashed cooked AYB to induce lactation after childbirth and the use of the fried ground seed coat to treat strokes (Table1). This conforms with the expectation implied in the ‘Convention on the Protection and Promotion of the Diversity of Cultural Expressions’ that the recognition of the links between biological and cultural diversity is often embedded with acknowledging the importance of indigenous knowledge and local peoples’ participatory roles in protecting and conserving biodiversity. This is because cultural diversity is a rich asset for safeguarding the vitality of societies; preserving cultural customs and practices and know-how that should be conserved [46]. Plants 2017, 6, 30 10 of 17

Table 1. Other uses of African Yam Bean in the ﬁve states of southeastern Nigeria.

Abia Anambra Ebonyi Enugu Imo Yes (dried plant after Fodder and part used - - Yes (dried plant after harvesting seed) - harvesting seed) Dried YAB snacks are Dried YAB snacks are Dried YAB snacks are Dried YAB snacks are Dried YAB snacks are recommended recommended for diabetic recommended for diabetic recommended for diabetic recommended for diabetic for diabetic patients. It makes them patients. It makes them patients. It makes them patients. It makes them patients. It makes them feel full. feel full. feel full. feel full. feel full. Eating AYB induces sleep Eating AYB induces sleep - as a result of its relaxing as a result of its relaxing ability (Insomnia) ability (Insomnia) Fried and ground seed is Fried and grinded seed is used to Medicine -- - used to treat stroke. treat stroke. Extract of mashed AYB after cocking is used to induce lactation in mothers Extract of mashed AYB Extract of mashed AYB after birth. after cooking is used to after cocking is used to The seed coat of roasted AYB is used in induce lactation in induce lactation in the treatment of stroke by a traditional mothers after birth. mothers after birth healer in Ehandiagu found in Nsukka LGA (Clem Uroko). Used as special food Used as special food Used as special food Used as special food Used as special food during festivals Cultural during festivals during festivals during festivals during festivals Women crop Women crop Women crop Women’s crop Women crop Poorer people crop Poorer people crop Poorer people crop Poorer people crop Poorer people crop Source: Field survey 2016. Plants 2017, 6, 30 11 of 17 Plants 2017, 6, 30 11 of 17

2.9. Constraints to Cultivation and Utilization of AYB AYB utilizationutilization and production in southeastern Nigeria is beset with a plethora of of problems. problems. Speciﬁcally,Specifically, the challenges confronting its use andand cultivation, determined for this study, are summarized in in Figure Figure 88.. Many of of the the respondents respondents can can be be classed classed as as aging aging farmers farmers (77.3%), (77.3%), and and it itwas was suggested suggested that that the the long long cooking cooking time time (76.6%) (76.6%) and and low low product product market market demand demand (71.6%) (71.6%) were the most intractableintractable problemsproblems confronting confronting AYB AYB cultivation cultivation and and utilization utilization in southeastern in southeastern Nigeria. Nigeria. Other constraintsOther constraints identiﬁed identified were the were lack the of stakinglack of materialsstaking materials (61.3%), postharvest(61.3%), postharvest diseases (59.9%)diseases and (59.9%) poor awarenessand poor awareness on the nutritional on the nutritional values of AYBvalues (57.1%), of AYB an (57.1%), important an important staple as wellstaple as as a cropwell ofas immensea crop of culturalimmense value cultural in southeastern value in southeastern Nigeria. Among Nigeria. the strategies Among forthe shortening strategies thefor long shortening cooking timethe long was soakingcooking seedstime was overnight soaking before seeds cooking overnight and/or before adding cooking the petioles and/or of adding paw-paw the (petiolesCarica papaya of paw-paw) to AYB seeds(Carica while papaya cooking) to AYB to reduce seeds thewhile challenge cooking of longto reduce cooking the time. challenge These challengesof long cooking could betime. attributed These tochallenges weak linkage could between be attributed research to weak and indigenouslinkage between knowledge. research and indigenous knowledge.

Poor availability of AYB seeds Long cooking time of AYB seed Lack of staking materials Poor seed quality Low yield of AYB Low awareness on nutritional values High cost of labour Lack of finance Aging of farmers Postharvest diseases

Constraints on utilization & cultivation of AYB & cultivation on utilization Constraints Low demand and market for AYB

0 102030405060708090 % Response

Figure 8. Constraints on the utilization and cultivation of AYB in southeastern Nigeria as determined by data from the 2016 ﬁeldfield survey.

2.10. Conservation and Management Indigenous communities in in the study area depend on plant genetic resources for livelihood sustenance. They have developed selective conserva conservationtion methods to protect these plants including AYB. ConservationConservation of AYB isis accomplishedaccomplished throughthrough thethe collectioncollection of dried fruits at maturity when the green fruits become brownish within the months of December to February. This is usually after harvesting thethe yamsyams (Dioscorea (Dioscoreaspp.) spp.) with with which which AYB AYB was stakedwas staked within with the farm.in the The farm. most The common most incommon situ conservation in situ conservation techniques techniqu used werees used restrictions were restrictions on use (eating on use just (eating a fraction just of a the fraction entire of seeds the harvested),entire seeds hanging harvested), the driedhanging fruits the beside dried thefruits cooking beside ﬁre the ether cooking inside fire the ether kitchen inside or outside,the kitchen beside or theoutside, house beside and or the storing house the and seeds or storing in calabash the seeds gourds, in calabash earthenware, gourds, plastic earthenware, cans and plastic bottles. cans Some and of thebottles. respondents Some of justthe tierespondents up the dried just fruits tie up in bundlesthe dried and fruits place in thembundles on anyand dry place platform them on outside any dry the houseplatform (Figure outside9). the house (Figure 9).

Plants 2017, 6, 30 12 of 17 Plants 2017, 6, 30 12 of 17

a b c

Figure 9.9. SphenostylisSphenostylis stenocarpa.stenocarpa.( a()a) Mature Mature but but not not ready ready to harvestto harvest the fruitsthe fruits of the of African the African yam bean;yam (bean.b) dried (b) fruits;dried fruits, (c) dried (c) harvesteddried harvested fruits stored fruits besidestored thebeside house the by house one ofby the one respondents. of the respondents. Photo © AdewalePhoto © Adewale and Nnamani. and Nnamani.

All these conservation methods often expose the seeds to pathogens thereby making them All these conservation methods often expose the seeds to pathogens thereby making them vulnerable to spoilage. This is in line with the reports by the UNESCO [46] that seeds of AYB were vulnerable to spoilage. This is in line with the reports by the UNESCO [46] that seeds of AYB were usually heavily infected with quite a number of pathogens. With respect to this, considerable efforts, usually heavily infected with quite a number of pathogens. With respect to this, considerable efforts, programs and policies should be made to aid the conservation of AYB seeds in the study zones. This programs and policies should be made to aid the conservation of AYB seeds in the study zones. This is is in line with the report of [47] that, to conserve underutilized species effectively, holistic in line with the report of [47] that, to conserve underutilized species effectively, holistic approaches approaches which include both the ex-situ and in-situ techniques must be planned to complement which include both the ex-situ and in-situ techniques must be planned to complement the local the local conservation strategies. conservation strategies. The remaining seeds of the 34 accessions of AYB used in this project were conserved ex-situ in The remaining seeds of the 34 accessions of AYB used in this project were conserved ex-situ in the the germplasm conservation unit of the Biotechnology Research and Development Centre, Ebonyi germplasm conservation unit of the Biotechnology Research and Development Centre, Ebonyi State State University Abakaliki, Nigeria and germplasm screening laboratory, Department of Crop University Abakaliki, Nigeria and germplasm screening laboratory, Department of Crop Production Production and Protection, Faculty of Agriculture, Obafemi Awolowo University, Ile-Ife, Nigeria. and Protection, Faculty of Agriculture, Obafemi Awolowo University, Ile-Ife, Nigeria.

3. Conclusions and Recommendations Globally it is recognized that indigenous knowledgeknowledge and its institutional systems provide the foundation for participatory strategies for eco-friendlyeco-friendly and societally sustainable development. This survey on the voice of the custodians of AYB in thisthis zonezone hashas actuallyactually contributed to the wealth of knowledge about AYB andand itsits sustainingsustaining potentialpotential inin foodfood securitysecurity resilienceresilience andand development.development. The social characteristics of respondents involved in AYB activities indicated that the preponderance of the elderly, whowho areare fastfast agingaging withwith littlelittle oror nono formalformal education,education, was high. While these traditional custodians of AYB areare passingpassing awayaway duedue toto oldold age, the younger generation has not shown enough interest in this crop. Furthermore, there was high variability in seed coat colours and patterns and this has a direct relationship with choice of selection of AYBAYB seedsseeds forfor cultivationcultivation andand use.use. However, inadequateinadequate information from extension officers,officers, a lack ofof stakingstaking materials,materials, long cooking time, low market demand, lack of appropriate conservation measures and unstable sources of income were among the factors against the cultivationcultivation and use of AYB. Apparently, thethe results results from from this this study study showed showed that thisthat rich this indigenous rich indigenous knowledge knowledge could provide could provide a guiding light for informed scientific inquiry to address current challenges. Protection of a guiding light for informed scientific inquiry to address current challenges. Protection of indigenous indigenous knowledge and its promotion among the scientific domain is urgently needed to knowledge and its promotion among the scientific domain is urgently needed to conserve and develop conserve and develop this crop [48]. As an integral component of the menu of the majority of the this crop [48]. As an integral component of the menu of the majority of the agrarian communities in agrarian communities in this zone, it could play a significant role on food security and economic this zone, it could play a significant role on food security and economic development. development. This study has unveiled some baseline data on the extensive dietary preparations and other latent This study has unveiled some baseline data on the extensive dietary preparations and other uses of AYB in addressing food security and sustainable development of these resource-poor rural latent uses of AYB in addressing food security and sustainable development of these resource-poor communities. Urgent local and national in-situ and ex-situ conservation approaches are highly needed rural communities. Urgent local and national in-situ and ex-situ conservation approaches are highly to ensure the continuous existence of this highly promising fading plant genetic resource in the face of needed to ensure the continuous existence of this highly promising fading plant genetic resource in change. The National Research Council [49] stressed the need for preliminary surveys, which could the face of change. The National Research Council [49] stressed the need for preliminary surveys, quickly be converted into advisory services to farmers who are the keepers of Africa’s age-old yam which could quickly be converted into advisory services to farmers who are the keepers of Africa’s bean heritage. This, they noted, could be done throughout the AYB zones with the aim of creating age-old yam bean heritage. This, they noted, could be done throughout the AYB zones with the aim of creating more awareness of its multipurpose assets, conserving the germplasm and improving the potentials of this crop.

Plants 2017, 6, 30 13 of 17 more awareness of its multipurpose assets, conserving the germplasm and improving the potentials of Plantsthis crop. 2017, 6, 30 13 of 17

4. Materials and Methods

4.1. Study Area The studystudy area area was was the the southeastern southeastern geo-political geo-politic zoneal ofzone Nigeria, of Nigeria, comprising comprising of Abia, Anambra,of Abia, Anambra,Ebonyi, Enugu Ebonyi, and Enugu Imo states and Imo regarded states asregarded the Igbo as land. the Igbo It is locatedland. It withinis located longitudes within longitudes 5◦300 and 5°309◦30′0 Eand and 9°30 latitudes′ E and 4◦ 30latitudes0 and 7 ◦4°30000 N,′ and occupying 7°00′ N, a landoccupying area of a about land 75,488area of km about2 (Figure 75,488 10) km and2 (Figurebordered 10) by and the bordered Cross River by the State Cross tothe River east, State Akwa to the Ibom east, to Akwa the south, Ibom Edoto the and south, Delta Edo States and toDelta the west,States andto the Kogi west, and and Benue Kogi States and toBenue the northStates [50to ].the Temperature north [50]. inTemperature the study areain the is characterizedstudy area is characterizedby two distinct by alternating two distinct seasons alternating of uniformly seasons of high uniformly temperature high temperature of 37 ◦C. The of aridity37 °C. The of thearidity dry ofseason the dry is accentuated season is accentuated by the dust-laden by the dust-laden harmattan harmattan winds (Northeast winds (Northea (NE) Tradesst (NE) Winds). Trades The Winds). mean Themonthly mean temperatures monthly temperatures oscillate between oscillate 23.3 between◦C and 27.7 23.3◦C °C with and a seasonal27.7 °C bimodalwith a seasonal annual rainfallbimodal of 1500–2500annual rainfall mm. of With 1500–2500 respect mm. to vegetation, With respect the age-longto vegetation, anthropogenic the age-long activities anthropogenic have given activities rise to havea derived given mosaic rise to ofa derived lowland mosaic rainforest of lowland vegetation rainforest type that vegetation houses a type relic that of the houses tropical a relic rainforest of the tropicalvegetation rainforest belt [50 ].vegetation belt [50].

Figure 10. DataData collection sites for Sphenostylis stenocarpa in southeast Nigeria.

4.2. Sample Size Representative samples of 10 respondents were selected randomly from 10 Local Government Areas (LGA) in a state, giving a total number of of 5 50000 respondents across across the the five ﬁve states states (Figure (Figure 10).10). The respondents included community heads, fa farmers,rmers, drivers drivers and and vendors vendors of of AYB AYB in these communities. The The selected selected 500 500 respondents respondents were were restricted restricted to those to those were were above above 18 years 18 years of age of and age older.and older. The The34 accessions 34 accessions collected collected from from the thestudy study areas areas after after the theresearch research were were conserved conserved ex-situ ex-situ in the germplasm conservation unit of the Biotechnology Research and Development Centre, Ebonyi State University Abakaliki, Nigeria and the germplasm screening laboratory of the Department of Crop Production and Protection, Faculty of Agriculture, Obafemi Awolowo University, Ile-Ife, Nigeria. Plants 2017, 6, 30 14 of 17 in the germplasm conservation unit of the Biotechnology Research and Development Centre, Ebonyi State University Abakaliki, Nigeria and the germplasm screening laboratory of the Department of Crop Production and Protection, Faculty of Agriculture, Obafemi Awolowo University, Ile-Ife, Nigeria.

4.3. Seed/Plant Collection Verbal pre-informed consent was obtained from the participants before they were interviewed. Interviews were conducted in the local language using guided semi-structured questionnaires and research assistants who were conversant with the local languages. These questionnaires were structured in line with the specific objectives of the study and were administered in the form of an oral interview scheduled in order to ensure that responses to the questions are correctly filled. The interviews were structured and covered questions pertaining to the uses of AYB, production and utilization constraints. The research questions were focused on (i) identifying the socio-economic status of the respondents; (ii) determining the uses, variability in seed coat colour and patterns; (iii) identifying the effects of climate change including those constraints limiting the use and production system of AYB; (iv) also requested was their knowledge of climate change effect on crops (with particular emphasis on AYB); (v) other uses such as its nutritional, medicinal, and cultural values including income extractable from AYB; and (vi) the demand profile of AYB in these communities. Rapid rural appraisal (RRA) and focal group discussion (FGD) were used to elicit farmers and stakeholders’ awareness and knowledge about climate change, its impact on their major staples; status of AYB and the challenges of cultivating it, while semi-structured interview schedules were used to collect quantitative information from the selected respondents. Farmers of AYB responded to a five-point scale survey employed to determine the magnitude of their responses: to a very great extent, five points; to a great extent, four points; to some extent, three points; to a little extent, two points; and to a very little extent, one point.

4.4. Income Extraction Validation The nutritional, medicinal, and cultural values, including income and demand proﬁle of AYB in these communities were accessed. Various vendors and different actors on AYB within the local markets participated in this study. The prices for this crop in the various zones as accruing from various transactions were sourced and recorded. Economic evaluation of the plant and its multipurpose uses were inventoried, rating these, and then converting these prices from the local currency to its USA dollar equivalent.

4.5. Data Analysis Data obtained from the questionnaires were processed into a data matrix, percentages and analysed. Data were analysed using simple averages, mean scores and standard deviations with Statistical Analysis System (SAS) to realize the objectives.

Acknowledgments: We appreciate African Academy of Science (AAS) and Association of Commonwealth Universities (ACU) for the award of a “Climate Impact Research Capacity and Leadership Enhancement (CIRCLE) to the first author for this project”. We are indebted to the Department for International Development (DfID) for funding CIRCLE and to the custodians of African yam bean, and Dept. of Crop Production and Protection, OAU, Nigeria for hosting this project. However, neither the findings nor the views expressed, however, necessarily reflect the policies of the UK Government. Author Contributions: Catherine Veronica Nnamani and Happiness Ogba Oselebe conceived and wrote the proposal. Catherine Veronica Nnamani designed the experiment, performed the experiments, analysed the data, and wrote up the manuscript, Sunday Adesola Ajayi supervised, designed the experiment and interpreted the data. Christopher John Atkinson restructured the proposal and corrected the manuscript while Anastasia Ngozi Igboabuchi and Eucharia Chizoba Ezigbo were involved in sample collections and the field survey together with Catherine Veronica Nnamani. Conflicts of Interest: The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data and in the writing of the manuscript, however, the funders’ have provided grant to publish this research work in an Open Access Journal. Plants 2017, 6, 30 15 of 17

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