Combination of irrigation and fertilizer increases yield and economic profit in carrot production

ABSTRACT This study aimed to carry out an economical and productive analysis of carrot production using different irrigation depths and doses of fertilizer. A randomized block design was used arranged in a 6 × 4 factorial scheme, with three replicates. The treatments were constituted by six irrigation depths: (L1: 210.5, L2: 315.7, L3: 421.0, L4: 526.2, L5: 631.5, and L6: 736.7 mm) and four doses of fertilizer: (F1: 226.9, F2: 340.3, F3: 453.8 and F4: 567.2 kg ha-1) applied via fertigation. At the end of the cycle, four carrot roots were collected per plot to estimate yield. The maximum estimated yield of the carrot was 95.4 t ha-1, obtained using 478.1 mm of water and 538.8 kg ha-1 of fertilizer. The best economic return was achieved with 482.0 mm of water and 460.0 kg ha-1 of fertilizer, giving 95.0 t ha-1. The combination of irrigation and fertilizer allows lesser amount of both to be used, giving greater response than when applied separately.摘要 本研究旨在针对不同灌溉定额与肥料用量下的胡萝卜生产开展经济性与生产性能分析。本试验采用随机区组设计，设置6×4析因试验方案，共设3次重复。试验处理包含6个灌溉定额水平：（L1：210.5、L2：315.7、L3：421.0、L4：526.2、L5：631.5、L6：736.7 mm），以及4个肥料用量水平：（F1：226.9、F2：340.3、F3：453.8、F4：567.2 kg·ha⁻¹），所有肥料均通过水肥一体化方式施用。在生育周期结束后，每个小区采集4根胡萝卜块根以估算产量。经估算，胡萝卜最高产量可达95.4 t·ha⁻¹，对应的灌溉定额为478.1 mm、肥料用量为538.8 kg·ha⁻¹。最佳经济收益对应的灌溉定额为482.0 mm、肥料用量为460.0 kg·ha⁻¹，此时的胡萝卜产量为95.0 t·ha⁻¹。相较于单独施用灌溉水或肥料，水肥耦合组合可通过降低两者的使用量获得更优的生产响应效果。