Dry-matter content at cutting and its relationships with morphological stage, N fertilization and weather data in the first growing cycle of Italian ryegrass for silage

abonos abonos nitrogenados application date chemical composition chromosome number composition chimique contenido de humedad contenido de materia seca contenido proteico crude protein cultivars date d'application developmental stages dry matter content engrais etapas de desarrollo fertilizers growth stages harvesting date lolium multiflorum madurez maturity moisture content nitrogen fertilizers nombre chromosomique nutritive value ploidy protein content proteina bruta teneur en eau valeur nutritive valor nutritivo variedades varieties water content