Effect of depth and width of cultivation and sowing date on establishment of red clover (Trifolium pratense L.) by rotary slot-seeding into grassland

摘要

The effect of different combinations of time of sowing and depth and width of soil cultivation using a rotary slot-seeding machine to introduce red clover (Trifolium pratense) was determined for some characteristics of newly established red clover plants in a lowland Dactylis glomerata-dominated grassland in the Czech Republic. Sowing was carried out on four sowing dates in one growing season: 11 May; 21 June (after the first cut); 9 August (after the second cut); and 19 September. The experimental treatments consisted of all combinations of four depths (5, 10, 15 and 20 cm) and four widths (5, 10, 15 and 20 cm) of soil cultivation. Measurements were made of number of plants, weight and height of plants, weight and height of roots. Measurements at 2 months after sowing showed fewer seedlings for the 11 May sowing than for later sowing dates. The number of red clover plants increased as the row width was increased up to 15 cm, regardless of the depth of slot. Positive effects of slot width on weight and height of plants and weight and length of roots were recorded. A highly positive correlation was found between weight of plants and weight of roots. Width of row was the key factor for the successful establishment of seedlings into the existing sward by slot-seeding. A row width of 10 cm and depth of slot of 5 cm was considered a satisfactory combination.