title: Combining Drought Survival via Summer Dormancy and Annual Biomass Productivity in Dactylis glomerata L.
abstract: Under Mediterranean climates, the best strategy to produce rain-fed fodder crops is to develop perennial drought resistant varieties. Summer dormancy present in native germplasm has been shown to confer a high level of survival under severe drought. Nevertheless it has also been shown to be negatively correlated with annual biomass productivity. The aim of this study was to analyze the correlations between summer dormancy and annual biomass productivity related traits and to identify quantitative trait loci (QTL) for these traits in a progeny of a summer dormant cocksfoot parent (Kasbah) and a summer active parent (Medly). A total of 283 offspring and the parents were phenotyped for summer dormancy, plant growth rate (PGR) and heading date in Morocco and for maximum leaf elongation rate (LERm) in France. The individuals were genotyped with a total of 325 markers including 59 AFLP, 64 SSR, and 202 DArT markers. The offspring exhibited a large quantitative variation for all measured traits. Summer dormancy showed a negative correlation with both PGR (-0.34 p < 0.005) and LERm (-0.27 p < 0.005). However, genotypes with both a high level of summer dormancy and a high level of PGR were detected in the progeny. One genetic map per parent was built with a total length of 377 and 423 cM for Kasbah and Medly, respectively. Both different and co-localized QTL for summer dormancy and PGR were identified. These results demonstrate that it should be possible to create summer dormant cocksfoot varieties with a high annual biomass productivity.
authors.affiliation: Unité de Recherche de Production Animales et Fourrage, INRA Maroc, Centre Régional de la Recherche Agronomique de Rabat Rabat, Morocco.
authors.forename: Rajae
authors.initials: R
authors.lastname: Kallida
authors.affiliation: Unité de Recherche de Production Animales et Fourrage, INRA Maroc, Centre Régional de la Recherche Agronomique de RabatRabat, Morocco; Laboratoire d'agroalimentaire et santé, Faculté des Sciences Techniques de Settat, Université Hassan 1erSettat, Morocco.
authors.forename: Latifa
authors.initials: L
authors.lastname: Zhouri
authors.affiliation: USC 1338, Centre d'Ecologie Fonctionnelle et Evolutive, UMR 5175, Institut National de la Recherche Agronomique Montpellier, France.
authors.forename: Florence
authors.initials: F
authors.lastname: Volaire
authors.affiliation: UR4 Unité de Recherche Pluridisciplinaire Prairies et Plantes Fourragères, Institut National de la Recherche Agronomique Lusignan, France.
authors.forename: Adrien
authors.initials: A
authors.lastname: Guerin
authors.affiliation: UR4 Unité de Recherche Pluridisciplinaire Prairies et Plantes Fourragères, Institut National de la Recherche Agronomique Lusignan, France.
authors.forename: Bernadette
authors.initials: B
authors.lastname: Julier
authors.affiliation: Unité de Recherche d'Amélioration des Plantes Valorisation et Conservation des Ressources Phytogénétiques, INRA Maroc, Centre Régional de la Recherche Agronomique de Rabat Rabat, Morocco.
authors.forename: Naima
authors.initials: N
authors.lastname: Shaimi
authors.affiliation: Laboratoire d'agroalimentaire et santé, Faculté des Sciences Techniques de Settat, Université Hassan 1er Settat, Morocco.
authors.forename: Malika
authors.initials: M
authors.lastname: Fakiri
authors.affiliation: UR4 Unité de Recherche Pluridisciplinaire Prairies et Plantes Fourragères, Institut National de la Recherche Agronomique Lusignan, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Barre
keywords: QTL; auto-tetraploid; cocksfoot; drought stress; forage; orchard grass