Effect of nitrogen supply on frost resistance, nitrogen metabolism and carbohydrate content in white clover (Trifolium repens)

adaptation amino acids carbohydrate content cold contenido de carbohidratos contenido proteico durcissement endurecimiento fertilisation fertilizer application frio froid frost gel hardening helada nitrogen content nitrogen metabolism protein content resistencia a la temperatura rhizobium leguminosarum root nodulation temperature resistance teneur en azote teneur en glucides trifolium repens