%0 Journal Article
%T AFLP/SSR mapping of resistance genes to Alectra vogelii in cowpea (Vigna unguiculata l. Walp)
%A C Kouakou
%A M Timko
%A R Akanvou
%A C Botanga
%A N Skizim
%A H Roy-Macauley
%J Sciences & Nature
%D 2009
%I 
%X The parasite weed Alectra vogelii (Benth) causes significant yield reduction of cowpea in Africa. To find and map the resistance gene to A. vogelii in cowpea, a F2 population from a cross involving a resistant parent IT81D-994 and a susceptible TVX3236 was screened. Amplified fragment length polymorphism (AFLP) in combination with Single Sequence Repeat (SSR) analysis was used to identify markers that may be linked to the gene Rav3 conferring resistance to A. vogelii in the cowpea cultivar IT81D-994. The analysis of F2 individuals scored for resistance showed that a single dominant gene conditioned A. vogelii resistance in IT81D-994 with a probability of 30 to 50%. Sixty-six AFLP/SSR markers were identified. Using MAPMAKER, four linkage groups were found. The first group showed 33 markers linked to the susceptible gene. The closest identified marker was 21.4 centimorgans away from the susceptible gene. The primer combination that showed the closest linkage was 809ACG8 (E-ACG 8 + UBC-809). The second group indicated 4 markers linked together while the third and the fourth groups showed 2 markers linked together respectively. No markers were found linked to the resistance gene Rav3 conferring the resistance in the cultivated cowpea cultivar IT81D-994. La plante parasite Alectra vogelii (Benth) provoque une r¨¦duction significative du rendement de ni¨¦b¨¦ en Afrique. Pour rep¨¦rer et cartographier le g¨¨ne de r¨¦sistance ¨¤ A. vogelii, une population F2 issue d¡¯un croisement impliquant le cultivar r¨¦sistant IT81D-994 et le cultivar sensible TVX3236 a ¨¦t¨¦ cribl¨¦e. La technique Amplified fragment length polymorphism (AFLP) en combinaison avec des S¨¦quences Simples R¨¦p¨¦t¨¦s (SSR) a ¨¦t¨¦ utilis¨¦e pour identifier les marqueurs qui seraient li¨¦s au g¨¨ne Rav3 qui conf¨¨re la r¨¦sistance ¨¤ A. vogelii chez le cultivar de ni¨¦b¨¦ IT81D- 994. L¡¯analyse des individus F2 montrant une r¨¦sistance indique qu¡¯un seul g¨¨ne dominant conditionne la r¨¦sistance ¨¤ A. vogelii chez IT81D-994 avec une probabilit¨¦ de 30 ¨¤ 50 %. Soixante six marqueurs AFLP/SSR ont ¨¦t¨¦ identifi¨¦s. A l¡¯aide de MAPMAKER, 4 groupes de liaison ont ¨¦t¨¦ trouv¨¦s. Le premier groupe montre 33 marqueurs li¨¦s au g¨¨ne sensible. Le marqueur le plus proche identifi¨¦ est ¨¤ 21.4 centimorgans du g¨¨ne sensible. La combinaison d¡¯amorces ayant des liaisons les plus proches ¨¦tait 809ACG8 (E-ACG 8 + UBC-809). Le second groupe montre 4 marqueurs li¨¦s ensemble tandis que le troisi¨¨me et le quatri¨¨me groupe montrent 2 marqueurs li¨¦s entre eux respectivement. Aucun marqueur n¡¯a ¨¦t¨¦ trouv¨¦ li¨¦ au g¨¨ne Rav3 qui conf¨¨re la r¨¦sistance au cultivar de ni¨¦b¨¦ cultiv¨¦ IT81D-994.
%U http://www.ajol.info/index.php/scinat/article/view/48580