CONSERVATION OF HELICONIA INFLORESCENCES PREVIOUSLY FERTILIZED WITH INCREASING DOSES OF NITROGEN AND POTASSIUM

ABSTRACT: The post-harvest of floral stems is one of the main features observed in the production of flowers for cutting, becoming a prerequisite for product quality and successful marketing. In this sense, the objective was to evaluate the conservation of heliconias inflorescences with or without renewal of the water maintenance, previously fertilized with increasing doses of nitrogen and potassium. Inflorescences of Heliconia psittacorum x H. spathocircinata cultivar Golden Torch were used and grown in open conditions in the Floriculture area at UFPI, city of Bom Jesus, Piauí State under increasing doses of fertilization with N and K. The stems were harvested in the morning, standardized and placed in containers with 500 mL of water. The design was a randomized block in factorial 4 x 4 x 2, corresponding to: i) N doses (0, 120, 180, and 240 g N hole-1), ii) K doses (0, 120, 180, and 240 g K2O hole-1), and iii) renewing the water maintenance in vase (with and without renewal) with three replicates of three stems each. Some evaluations were observed during the Study, such as: the water uptake by the flower stems; loss of fresh weight of the flower stems, dry weight of the flower stems and post-harvest longevity. The dose of 180 g hole-1 both as N and K provided the longevity of the flower stems with quality maintenance. The absorption of water by the flower stems and its dry mass after harvesting are influenced by previous fertilizer N and K. The renewal of the water maintenance also positively influence the longevity of flower stems and its a management indicated to maintain quality post-harvest.

摘要：花茎采后处理是切花生产的核心环节之一，亦是保障产品品质与成功市场化的前提条件。据此，本研究旨在评估经不同梯度氮、钾基肥施用后的蝎尾蕉（Heliconia）花序，在不同换水条件下的保鲜效果。试验以鹦鹉蝎尾蕉（Heliconia psittacorum）×spathocircinata蝎尾蕉杂交品种‘金火炬’（Golden Torch）为材料，于巴西皮奥伊州邦热苏斯市的皮奥伊联邦大学（UFPI）花卉栽培试验区露地种植，施以递增梯度的氮、钾肥料。花茎于清晨采收，经标准化处理后置于盛有500mL清水的容器中。试验采用4×4×2因子组合的随机区组设计，具体处理如下：①氮素施用量（每穴0、120、180、240g氮）；②钾素施用量（每穴0、120、180、240g氧化钾（K₂O））；③瓶插水养护方式（换水与不换水），每个处理设置3次重复，每次重复包含3支花茎。本研究测定的指标包括花茎吸水量、鲜重损失率、干重及采后瓶插寿命。结果表明，当氮、钾施用量均为180g穴⁻¹时，可有效维持花茎品质并延长瓶插寿命。花茎的水分吸收量与采后干重均受前期氮、钾施肥处理的显著影响。定期换水亦可显著提升花茎瓶插寿命，是保障采后品质的有效养护措施。