The influence of different ways of alfalfa (Medicago sativa L.) stands cultivation on its yield capacity

The influence of different terms (spring, after the 1(st), 2(nd) or 3(rd) c uts) and ways of cultivation (spike harrow, vibration harrow) on yield capa city of alfalfa (Medicago sativa L.) cv. Zuzana was studied in a plot polyf actorial trial in Cerveny Ujezd 405 m above the sea level, on clay loam ort hic luvisol in the years 1997-1999. Alfalfa was sown in the spring without a companion crop to rows of a space 125 mm, sowing rate 16 kg(.)ha(-1) germ ination seeds. The trial had 10 replications and it was cut 3 times per yea r. The total yield of dry above-ground mass in the 2(nd) year of vegetation was not significantly influenced by harrow cultivation. The efficient cult ivation of the stands by vibration harrow to the depth 70 mm after the 2(nd ) or 3(rd) cuts resulted in significant decrease of dry mass yield in the 3 (rd) year of vegetation by 7.2-21.1%, tin average by 11%) in comparison wit h the control variant. The amount of stems per 1 m(2) in the cultivated plo ts was mostly lower than in the control in average by 1.2-8.8% in the 2(nd) year of vegetation. Sporadic higher amount of stems in the cultivated plot s in individual cuts did not result in their higher total amount in the 3(r d) year. The amount of plants per 1 m(2) was not significantly influenced b y cultivation during 3 years.