Seed productivity of Festulolium and Lolium x boucheanum varieties under climatic conditions of Latvia

摘要

The aim of this research was to study the winter hardiness and seed yield of seven foreign varieties of Festulolium and Lolium x boucheanum under the agro-ecological conditions of Latvia. The intergeneric hybrid variety 'Saikava' (L. perenne x F. pratensis), developed at the Skriveri Research Center of the Latvia University of Agriculture, was used as control. Field trials were carried out on sod - podzolic soil during 2002-2004. The mineral fertilizer rates used were: N-90, N-120, and P-104, K-150. The productivity of DM and seeds depended on the variety, mineral fertilizer rates and meteorological conditions prevailing in each investigation year. Some parameters were influenced by the genetic characteristics of particular cultivars. The average seed yield of Festulolium amounted to 944 kg ha~(-1) at the N fertilizer rate of 90 kg ha~(-1). At the N fertilizer rate of 120 kg ha~(-1) the seed yield increased by 76 kg ha~(-1). The average seed yield of hybrid ryegrass amounted to 598 kg ha~(-1) at the N fertilizer dose of 90 kg ha~(-1). The increase of N fertilizer to 120 kg ha~(-1) raised the seed yield by 57 kg ha~(-1). Lodging was greater with high fertilization rates. The correlations between the seed yield and the seed weight, number of generative tiller and stem length were significant.