Sod production and the effects of liquid organo-mineral fertilizers and thickness of sod

ABSTRACT: Nitrogen fertilization and an appropriate cutting thickness can result in firmer sod that can be handled in less time with greater turfgrass regrowth during the subsequent cycle. This experiment was conducted on a sod production farm located in Capela do Alto, in the state of Sao Paulo, Brazil. The soil was a dystrophic Rhodic Hapludox (Oxisol) with a medium texture. The experiment had two statistical designs; the initial design was randomized blocks with seven treatments and four replicates. Treatments were five doses of liquid organo-mineral fertilizer (OMF) corresponding to 0, 100, 200, 300 and 400 kg ha−1 of nitrogen (N) with supplementation of phosphorous (P) and potassium (K) as well as two control treatments - one with 300 kg ha–1 of N as OMF and the other with 300 kg ha−1 of N-urea + P and K. At harvest, the adopted design was a split-plot type with four replicates in a 7 × 3 factorial arrangement with seven treatments as the main plot and three sod cutting heights (9, 16 and 22 mm) as subplots. Nitrogen doses in the form of OMF influenced the percentage of ground cover (PGC) by turfgrass in both cycles. The N dose of 300 kg ha−1 formed the sod more quickly and provided the largest mass of roots and stolons and the highest sod tensile strength. The thinnest sod samples had faster regrowth and provided higher PGCs.

摘要：施加氮肥并搭配适宜的草皮修剪厚度，可获得紧实度更佳的草皮，在后续生长周期中能缩短采收耗时并提升草坪草的恢复生长能力。本试验于巴西圣保罗州卡佩拉杜阿尔图的草皮生产农场开展，供试土壤为中质地贫养质红化简育湿润铁铝土（Oxisol）。试验采用两套统计设计：初始设计为随机区组设计，包含7个处理、4次重复。处理组为5个液态有机-矿质肥料（OMF）施用量梯度，分别对应0、100、200、300及400千克每公顷（kg ha⁻¹）的氮（N）施用量，同时补充磷（P）与钾（K）；另设2个对照组，其一为施用OMF型氮肥300 kg ha⁻¹，其二为施用尿素型氮肥300 kg ha⁻¹并搭配P、K。采收阶段采用裂区设计，以7×3因子排列设置4次重复，主区为前述7个处理，副区为3个草皮修剪高度（9、16及22 mm）。研究表明，以OMF形式施加的氮肥施用量会影响两个生长周期内草坪草的盖度百分比（PGC）。当施氮量为300 kg ha⁻¹时，草皮形成速度最快，根系与匍匐茎生物量最大，且草皮抗拉强度最高。修剪厚度最小的草皮样品恢复生长速度更快，盖度百分比也更高。