Non-overwintering cover crops: a significant source of N

摘要: In field experiments in 1982-89 at 2 sites the Netherlands, potatoes cv. Bintje and sugarbeet Monohil or Ovatio a wheat/potatoes/wheat/sugarbeet rotation were preceded during winter by fallow green manure crop of Lolium multiflorum Tetila with 0 (G0), 100 (G100) 200 kg N/ha (G200) Trifolium pratense Rotra no N (RC). Green crops undersown to wheat Durin ploughed first half November. On average, G0, G100, G200 RC had then accumulated 22, 93, 125 57 N/ha, respectively, above-ground plant parts. G0 tended immobilize soil mineral spring generally non-significant effects on yields sugarbeet, whereas increased marketable significantly. Effects mainly attributable release manures. The fertilizer value manures was evaluated their effect economic optimum rates, yield when supplied. last two methods appeared be most appropriate for present experiments. Fertilizer values ranged from -21 108 depending type calculation method. About parts available G100 its yields. From this even greater, although may partly have resulted transfer that not been taken up crop. Due high content roots stubble, provided, almost double amount also minor positive grain following sugarbeet. At least 35% L. utilized within 18 months after incorporation.