Krasova-Wade Tatiana, Ndoye Ibrahima, Braconnier Serge, Sarr Benoit, De Lajudie Philippe, Neyra Marc. 2003. Diversity of indigeneous bradyrhizobia associated with three cowpea cultivars (Vigna unguiculata (L.) Walp.) grown under limited and favorable water conditions in Senegal (West Africa). African Journal of Biotechnology, 2 (1) : 13-22.
Autre titre : Diversité de bradyrhizobia indigènes associés avec trois cultivars de niébé (Vigna unguiculata (L.) Walp.) cultivés en conditions hydriques limitatives ou favorables au Sénégal (Afrique de l'ouest)
Résumé : The diversity of #Bradyrhizobium# strains nodulating three cowpea (#Vigna unguiculata# L. Walp.) cultivars in favorable and water-limited conditions occuring at flowering was analysed. PCR-Restriction Fragment Length Polymorphism (PCR-RFLP) analysis of 16S-23S rDNA intergenic spacer region (IGS) directly applied on 85 crushed nodules distinguished four genetic profiles, IGS types l, ll, lll and IV. The distribution of these IGS types according to water conditions and cowpea cultivars (B-21, TN 88-63 and Mouride) showed that nodulating strains appeared more diverse in water-limited condition. More than three quarters of prospected nodules presented the IGS type l. They were formed on all three cultivars and in both water conditions. Only a small part of nodules was distributed between the IGS type ll, lll and IV. Nodules showing the IGS types ll and III were found mainly in limited conditions on TN 88-63 and Mouride cultivars, whereas nodules presenting the IGS type IV were collected only from cultivars B-21 and Mouride, in both water conditions. Strains corresponding to the different profiles were isolated. The phylogenetic analysis of 16S rRNA gene sequences showed that they belong to the genus #Bradyrhizobium#. The sequence analysis of 16S-23S rDNA IGS revealed that the strains exhibiting IGS types ll, lll and IV were closely related to some #Faidherbia albida# isolates from Senegal. IGS type ll can be assigned with at least 98% similarity to #Bradyrhizobium# genospecies IV. IGS types III and IV showed more than 96% similarity with genospecies Vll and could belong to the same genospecies. IGS type l, the most frequent, exhibits low IGS similarity with reported sequences in the databases, and could represent a new genospecies.
Mots-clés Agrovoc : Vigna unguiculata, Bradyrhizobium, variation génétique, RFLP, empreinte ADN, privation d'eau, variété
Mots-clés géographiques Agrovoc : Sénégal
Classification Agris : P34 - Biologie du sol
F30 - Génétique et amélioration des plantes
Auteurs et affiliations
- Krasova-Wade Tatiana, IRD (SEN)
- Ndoye Ibrahima, IRD (SEN)
- Braconnier Serge, CIRAD-AMIS-AGRONOMIE (SEN)
- Sarr Benoit, CERAAS (SEN)
- De Lajudie Philippe, IRD (FRA)
- Neyra Marc, IRD (SEN)
Autres liens de la publication
- Document en bibliothèque
- Localisation du document : CD_BR11504 [(Bibliothèque de Lavalette)]
Source : Cirad - Agritrop (https://agritrop.cirad.fr/513529/)
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