The effect of nitrogen on the root and shoot development of Lolium multiflorum var. westerwoldicum.

Westerwolds ryegrass was grown in tubes on artificial soil profiles at N rates equivalent to 25, 50 or 100 kg/ha with a water table maintained 70 cm below the soil surface. Average results/plant after 13 weeks at low and high N were: DM yield of tops 5.0 and 14.6 g, water consumption 2660 and 4850 cm2, DM yield of roots 1.4 and 3.4 g, total length of all primary roots 2589 and 3374 cm, number of primary roots 103 and 161, number of secondary roots in topsoil 63 and 83 and in subsoil 71 and 83, and total root surface area 1084 and 1736 cm2. ADDITIONAL ABSTRACT: L. multiflorum plants were grown on sandy soil in asbestos tubes with an inner diameter of 15 cm, and 75 cm high, and supplied with 25, 50 or 100 kg N/ha. The soil water level was maintained at 70 cm below soil level. Top growth 8 and 13 weeks after sowing was progressively enhanced by the 2 higher rates, weight increments amounting to at least 72 and 188 %, respectively. These growth increases were accompanied by augmented water consumption, as well as root growth and numbers. (Abstract retrieved from CAB Abstracts by CABI’s permission