The compatibility of Trifolium resupinatum cv. Shaftal Maral and Lolium multiflorum (type Westerwolds) cv. Energa in mixtures as affected by nitrogen application and different seeding rates

Abstract

Nitrogen fertilizer was applied at four different rates to pure and mixed stands of irrigated Trifolium resupinatum and Lolium multiflorum to study their compatibility. Dry matter production, crude protein content, crude protein production and the Land Equivalent Ratio were determined for each treatment. Results showed that pure stands of grass and clover did not outyield any of the mixtures, planted at three different grass seeding rates. The botanical composition of the mixtures shifted from a grass dominant to a clover dominant sward during the growing season, notably with no or little nitrogen application. The crude protein content of the grass in mixtures benefitted from the presence of the clover at low nitrogen levels, probably either by transference of clover fixed nitrogen or by less competition between grass and clover plants for applied nitrogen. In terms of the Land Equivalent Ratio the pure grass, fertilized with 540 kg N ha⁻¹ had no yield advantage over any of the mixtures. Also, the mixtures showed no response to either increased nitrogen application or grass seeding rates.

Keywords:

• Annual pastures
• competition
• crude protein content
• dry matter production