Showing papers by "Congrès International d'Architecture Moderne published in 2000"

Breeding Potential of European Flint and U.S. Corn Belt Dent Maize Populations for Forage Use

Abstract: Information about appropriate breeding populations and the type of forage maize (Zea mays L.) hybrids that should be developed for cooler regions of Europe is scarce. Our objectives were to determine the potential, performance, and heterosis of flint (F) and dent (D) populations as base germplasm for developing silage maize hybrids. Four U.S. Corn Belt dent populations which had been selected for early maturity and four European flint populations were included in our study. The eight populations, the 28 possible crosses among them, and topcrosses to inbreds A632 and EC18 were evaluated for stover, ear, and whole plant dry matter yield (DMY), as well as stover and whole plant dry matter content (DMC), digestible organic matter (DOM), and add detergent fiber (ADF) content in northwest Spain. Means of F x D population crosses for stover and ear DMY (6.98 and 8.71 Mg ha -1 , respectively) were greater than those of D x D crosses (6.12 and 8.05 Mg ha -1 , respectively) and F × F crosses (6.03 and 7.64 Mg ha -1 , respectively). Average heterosis of whole plant DMY was greater for the F × D crosses (2.16 Mg ha -1 ) than for the D × D and F x F crosses (0.23 and 0.56 Mg ha -1 , respectively). No significant heterosis was found for DOM and ADF of the stover and whole plant fractions. The only exception was a negative average heterosis of population BSSS-M for stover DOM. Results suggest that forage maize hybrids should be developed from the F x D heterotic pattern. Breeding strategies should include selection for stover DOM for both parent lines and hybrids because favorable recessive genes may be involved in this trait.

Agromorphological and grain quality characterisations of northern Spanish wheats under low-nitrogen conditions

Abstract: Quinze varietes de pays de ble ont ete evaluees sous une fertilisation azotee faible (50 kg N.ha -1 .an -1 ) au Centre de Recherche Agronomique de Mabegondo pendant deux ans dans un dispositif en deux blocs complets randomises ou la parcelle elementaire etait un rang de 2 m. Deux cultivars commerciaux de ble (Marius et Soissons) ont ete aussi evalues. Sept caracteres qualitatifs et 15 caracteres quantitatifs ont ete consideres. Cet ensemble de donnees a ete reduit a quatre composantes principales qui expliquent 80 % de la variance totale. La classification ascendante hierarchique a permis l'identification de trois groupes differencies de varietes de pays. En general, les varietes locales de ble ont eu des performances agronomiques similaires aux cultivars commerciaux a l'exception de faibles valeurs du test Zeleny pour la plupart des varietes locales. La conservation, si possible in situ, de telles ressources nous parait un objectif prioritaire.