Auteur: Grygierzec B., Szewczyk W. and Musiał K.
Jaar van uitgifte: 2015
The aim of this study was to determine the effect of sulphur fertilization on the rate of photosynthesis and yield of hybrid ryegrass (Lolium × boucheanum) grown in monoculture and mixture with white clover (Trifolium repens). The study was conducted in a split-plot design with four replications. Soil conditions were degraded chernozem formed from loess. The fertilization scheme was 50 and 100 kg N ha‑1, 35 kg P ha‑1, 83 kg K ha‑1, and sulphur at 5, 10 and 15 kg S ha‑1. The intensity of photosynthesis was measured in each regrowth at weekly intervals using a portable gas analyser (Li-Cor 6400). Plants were mown 3 times during the growing season. Both nitrogen and nitrogen-with-sulphur fertilization positively influenced the rate of photosynthesis in each regrowth. Sulphur fertilization compared to nitrogen fertilization increased the rate of photosynthesis in hybrid ryegrass grown in monoculture. Total dry matter yields of hybrid ryegrass grown in monoculture were lower than in mixture with white clover, irrespective of the amount of nitrogen or nitrogen-and-sulphur fertilization. The biggest difference in yields between the monoculture and the mixture was found with 100 kg N and 15 kg S ha‑1. The smallest difference was shown in treatments fertilized with 50 kg N and 5 kg S ha‑1.