Agronomic and molecular evaluation of cocksfoot and tall fescue cultivars for adaptation to an Algerian drought-prone environment
Résumé
A prime objective for improving perennial grasses for Mediterranean environments is the identification and selection of genotypes well adapted to semi-arid conditions. This study was conducted at an experimental site in Algeria over three consecutive seasons, with the aim of evaluating the agronomic performance and genetic diversity of 13 cultivars of two species of perennial grasses: six cocksfoot (Dactylis glomerata L.) and seven tall fescue (Festuca arundinacea Schreb. = syn.Lolium arundinaceum (Schreb.) Darbysh.) cultivars. Variation was found in both species for dry-matter yield, sward recovery, heading date, water-use efficiency (WUE), and summer senescence. Tall fescue cultivars gave greater yield in spring, with earlier heading date and higher WUE than cocksfoot, with no differences for the other traits. Among the genotypes, 'Flecha' was the most promising, together with 'E-542', 'Fraydo' and 'Centurion', all of which are tall fescue cultivars. Principal component analysis indicated that persistence of grass cover is relatively independent from dry-matter yield and water-use efficiency. The level of genetic diversity within each species was assessed using AFLP markers, and the molecular variation was analysed together with agronomic trait variation, with identification of molecular markers potentially associated with the relevant traits.