INFLUENCE OF SOWING TIMES ON THE PRODUCTIVITY AND CHEMICAL COMPOSITION OF A HERBACEOUS MIXTURE UNDER THE CONDITIONS OF THE TROYAN REGION

摘要

During the period 1991 - 1998 a field trial was carried out in the Troyan region on light grey pseudopodzolic soil with pH 4,0 in KCI. The trial was laid out by the block method with a herbaceous mixture of birdsfoot trefoil, red clover, cocksfoot andred fescue in order to determine the influence of the following sowing times: 1. 1-10 Sept.; 2. 1-10 Oct.; 3. 1-10 Nov.; 4. 1-10 Dec.; 5. 1-10 Jan.; 6: 1-10 Feb.; 7. 1-10 March; 8. 1-10 April (control); 9. 1-10 May. The highest dry mass yield was foundfor the sowing time 1-10 Oct. when the yield reached 969,0 kg/da and exceeded the control by 15,4%. The most favourable sowing time for crude protein content was the period 1-10 May (96,0 g.kg~(-1)) and for crude fibre content the period 1-10 April (275,9 g.kg~(-1)). Calcium reached its maximum when sowing in spring 1-10 March (10,1 g.kg~(-1)) and phosphorus when sowing in the period 1-10 April (3,8 g.kg~(-1)).