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：切花茎秆采后管理是切花生产的关键环节之一，是保障产品品质与实现商业化销售的先决条件。本试验旨在评估预先施加递增剂量氮钾肥的蝎尾蕉（Heliconia）花序，在瓶插补水与不补水条件下的保鲜效果。供试材料为鹦鹉蝎尾蕉×蝎尾蕉‘金火炬’（Heliconia psittacorum x H. spathocircinata cv. Golden Torch）的花序，于巴西皮奥伊州邦热苏斯市皮奥伊联邦大学（UFPI）切花栽培区露地种植，施加递增梯度的氮、钾肥。试验于清晨采收茎秆，经标准化预处理后置于盛有500 mL清水的容器中。试验采用4×4×2因子设计的随机区组方案，具体处理组合为：i) 氮肥施用量（每穴0、120、180、240 g纯氮）；ii) 钾肥施用量（每穴0、120、180、240 g氧化钾）；iii) 瓶插补水操作（补水与不补水），每处理设置3次重复，每次重复包含3个茎秆。本试验测定的指标包括：切花茎秆吸水量、鲜重损失率、采后干重及采后保鲜期。结果表明，每穴施180 g的氮、钾肥用量可在维持切花品质的前提下延长茎秆保鲜期；切花茎秆的吸水量及采后干重均受前期施加的氮钾肥用量影响；瓶插补水同样可显著延长切花茎秆保鲜期，是维持切花采后品质的推荐管理措施。