The influence of weeds on cereal crops - competition, plant diseases, harvesting problems, and product quality

avena biological competition calidad cultivos de invierno cultivos de primavera culture d'hiver culture de printemps facteur de rendement factores de rendimiento hordeum light regimes population density quality regimenes de luz rendement rendimiento secale cereale seed semence semillas soil types spring crops triticum type de sol variedades varieties winter crops yield factors yields