THE EFFECTS OF LIVING MULCHES ON YIELD, OVERWINTERING AND BIOLOGICAL VALUE OF LEEK

In field study conducted in 1998-2001 leek cv. Arkansas was grown from seedlings planted on 10 June. Perennial ryegrass, white clover and hairy vetch used as the living mulches were sown between plant rows after 3, 5, 7, 9 and 11 weeks from the date of transplanting. Harvest of leek was conducted in October or in early April, after overwintering the plants in the field. In both terms samples of edible parts were collected for chemical analysis.
During autumn harvest the first two sowings of living mulches considerably reduced the leek biomass and marketable yield by 59.7 % and 31.0 %, respectively. Sowings delayed to 7, 9 and 11 weeks after transplanting did not adversely affect plant growth and yield of leek. The most competitive species for leek growth appeared to be hairy vetch, which sown 3 or 5 weeks after planting overtopped leek plants and caused heavy reduction of the yield. White clover and hairy vetch in treatments with first two sowings were the most preferable for leek overwintering.
Living mulches did not influence the content of dry matter, vitamin C, total and reducing sugars in edible parts of leeks. Plants harvested in spring season contained lower amounts of dry matter and total sugars, while higher level of reducing sugars.