Evolution de la diversité des cultivars de fonio pratiqués dans la commune de Boukoumbé au Nord-Ouest du Bénin

Abstract

REMERCIEMENTS Ce travail a été sponsorisé par le Conseil Scientifique de l'Université de Parakou à qui nous adressons nos sincères remerciements. RESUMEAfin de comparer la diversité actuelle des écotypes de fonio à celle cultivée dix (10) ans plus tôt au Bénin, une enquête a été menée en 2013 dans la commune de Boukoumbé. Dans chacun des vingt (20) villages prospectés, un focus groupe d'une douzaine de producteurs a été à chaque fois enquêté. Cinq (5) à dix (10) producteurs sont ensuite entretenus individuellement à l'aide d'un questionnaire semi-structuré pour recueillir des informations sur les cultivars, leurs noms locaux, leurs principales caractéristiques, et la gestion des semences. Les résultats ont confirmé la diversité des appellations et ont permis de recenser cinq (5) cultivars différenciés par la précocité, la couleur des racèmes, les tailles de graines et de plantes. Les semences, transmises surtout de génération en génération, sont prélevées à 99% sur les récoltes précédentes. Près de 95% des enquêtés cultivent une seule variété à la fois. La plus forte diversité a été rencontrée chez les "Ditamaris" des villages de Boukoumbé-centre et Natta. "Iporapia" et "Takotapuaka" sont cultivés par toutes les ethnies. La diversité décrite dix (10) ans plus tôt dans la zone a été maintenue. Toutefois, les variétés de précocités extrêmes sont de moins en moins cultivées, et donc menacées de disparition. © 2015 International Formulae Group. All rights reserved.Mots clés : Espèce négligée, accession de fonio, Digitaliaspp., conservation in situ, amélioration variétale, Bénin.E. SEKLOKA et al. / Int. J. Biol. Chem. Sci. 9(5): 2446-2458, 2015 2447 Evolution of the diversity of fonio cultivars practiced in the commune of Boukoumbe in North-West of Benin ABSTRACTTo compare the current diversity of landraces of millet fonio to that cultivated ten (10) years ago in Benin, a survey was conducted in 2013 in the district of Boukoumbé. In each of the twenty (20) villages surveyed a focus group of a dozen producers was investigated every time. Then, five (5) to ten (10) producers are individually interviewed using a semi-structured questionnaire to collect information on cultivars, their local names, their main characteristics and seed management. The results confirmed the diversity of names and allowed to identify five cultivars differentiated by the earliness, color of racemes, sizes of seeds and plant height. Seeds, especially transmitted from generation to generation, are taken at 99% on the previous harvest. Nearly 95% of respondents grow only one variety at a time. The greatest diversity was encountered among the "Ditamaris" of villages in Boukoumbé center and Natta. "Iporapia" and "Takotapuaka" are cultivated by all ethnic groups. The diversity described ten (10) years earlier in the area has been maintained. However, the extreme precocity varieties are lesser and lesser grown, and therefore at risk of extinction.

Effects of Planting Density and Manure on Maize (Zea mays L.) Agronomic Parameters in Bouaké, Côte d’ivoire

“…These types of crop density are therefore not favorable. [25] made similar observations on cotton. These authors noted that seeds sown at very high densities produced plants whose stems were shorter with fewer nodes.…”

Agromorphological Characterization Revealed Three Phenotypic Groups in a Region-Wide Germplasm of Fonio (Digitaria exilis (Kippist) Stapf) from West Africa

“…In traditional fonio farming systems of West Africa, all cultivated varieties are landraces [8]. Their productivity is limited due to the lack of improved varieties and good agronomic practices, lack of institutional support, lack of knowledge about some biotic and abiotic stresses, and tedious post-harvest activities [9].…”

Mass selection of fonio landraces (Digitaria exilis) grown in Benin: Pathway, homogeneity assessment and genotypes screening

“…Indeed, many authors have emphasized that farmers’ seed management practices, particularly exchanges of varieties between farmers, promote gene flow which helps to broaden the genetic diversity between populations of grown plants (Delaunay et al., 2008; Mckeye et al., 2001; Missihoun et al., 2012; Sawadogo et al., 2014). As described in Nigeria (Kwon‐Ndung & Dachi, 2007), the main access mode to fonio seeds in Benin regions is the collection of seeds from the previous year's harvest and the varieties exchanged between farmers (Adoukonou‐Sagbadja et al., 2006; Dansi et al., 2010; Sekloka et al., 2015).…”

“…This also partly highlights the effectiveness of homogenization selection achieved by accessions purification from grains colour on the racemes at maturity. The grains colour has been widely considered as a key criterion for the varietal distinction of fonio (Adoukonou‐Sagbadja et al., 2006; Dansi et al., 2010; Sekloka et al., 2015). This shows once again the fact that mass selection is more effective on major visual traits (Abreu et al., 2010; Ngandu‐Nyindu, 1981), as they are generally known as more heritable traits (Acquaah, 2007).…”

“…Consequently, the grown varieties so far are traditional cultivars (landraces) evolving from farmer selection during many centuries of cultivation (Adoukonou‐Sagbadja et al., 2007, 2010; Portères, 1976). Access to seeds is essentially traditional, mainly based on the collection from the previous harvest, on exchanges between farmers and sometimes on the seeds purchase at the market (Adoukonou‐Sagbadja et al., 2006; Dansi et al., 2010; Sekloka et al., 2015). From the artificial selection of varieties, farming practices and traditional mode of seed management, it results that grown landraces of fonio are often in polyvarietal mixture, and therefore presents intra‐varietal heterogeneity (Adoukonou‐Sagbadja et al., 2010; Kwon‐Ndung & Dachi, 2007; Sekloka et al., 2015).…”