Biostimulant effect on the initial growth and yield of sweet potato

ABSTRACTThe use of biostimulants in agriculture has shown positive effects on the yield of some crops. However, there are few studies on the use of these products in crops which commercialized parts are the roots. This study aimed to evaluate the influence of different concentrations of the biostimulant Stimulate(r)on the sweet potato initial growth and tuberous root yield. Two experiments were carried out using stem segments partially immersed in solutions containing biostimulant. In a greenhouse experiment, the experiment was arranged in a completely randomized 6 x 6 factorial design, with six biostimulant concentrations (0, 3, 6, 9, 12 and 15 mL L-1)and six collection times (10, 19, 28, 37, 46 and 55 days after planting) of roots and leaves. In the field, the experiment was arranged in a randomized block design, and the treatments consisted of six biostimulant concentrations (0, 3, 6, 9, 12 and 15 mL L-1). The percentage of rooted segments was not affected by the treatments. The biostimulant influenced the number of roots and leaves, but their dry mass was not affected. The tuberous root yield was not different among treatments, with mean values of total and commercial yields equal to 25.5 and 22.3 t ha-1, respectively. Therefore, the biostimulant interferes in the number of roots and leaves, but it does not increase yield of tuberous root up to the concentration of 15 mL L-1.

摘要 农业生产中，生物刺激素（biostimulant）的应用已被证实对部分作物的产量具有积极促进作用。然而，针对商业化收获部分为根系的作物开展的此类产品应用研究仍较为稀缺。本研究旨在评估不同浓度的生物刺激素Stimulate(r)对甘薯初期生长及块根产量的影响。本研究通过将茎段部分浸没于含生物刺激素的溶液中开展两组试验：温室试验采用完全随机6×6析因设计，设置6个生物刺激素浓度梯度（0、3、6、9、12和15 mL·L⁻¹）与6个采样时间点（移栽后10、19、28、37、46及55天），采集根与叶样本；田间试验采用随机区组设计，处理组同样设置6个生物刺激素浓度梯度（0、3、6、9、12和15 mL·L⁻¹）。试验结果表明，各处理组对茎段生根率无显著影响；生物刺激素可显著影响根系与叶片的数量，但对其干物质重量无明显调控作用；各处理组的块根产量无显著差异，总产与商品产均值分别为25.5 t·ha⁻¹与22.3 t·ha⁻¹。综上，生物刺激素仅对甘薯的根系与叶片数量存在干预效果，在浓度不超过15 mL·L⁻¹的范围内，未能提升块根产量。