ABSTRACT
This work had the goal to evaluate the influence of temperature and dry storage on the postharvest longevity of Epidendrum ibaguense flowers previously treated with silver thiosulfate (STS). The flowers were harvested and pulsed for 30 minutes with 2 mM STS. Then both, the STS treated and untreated flowers were packed in perforated low density polyethylene bags, packed in cardboard boxes and stored at 5 and 10°C, where they remained for four and eight days. After this period, the flowers were kept in vase with distilled water at 25ºC, and analyzed at every 24 h. The experiment was arranged in a complete random design 2 x 2 x 2 factorial scheme, with four replicates, containing four inflorescences each, except for the determination of transpiration and water rates uptake, composed by sixteen replicates of one stem. The vase life of the flowers of the E. ibaguense was increased to 6.5 days when pulsed with 2 mM STS for 30 minutes, followed by storage at 10ºC for a maximum period of four days. The STS applied before the cold storage reduced the rate of flower abscission and improved the ratio between the transpiration and water uptake.
ABSTRACT
O objetivo deste trabalho foi avaliar o efeito de diferentes soluções sobre a reidratação e longevidade de inflorescências de boca-de-leão após armazenamento refrigerado a seco. As hastes foram colhidas com seis a sete flores abertas e, após 24 horas em água, foram embaladas em papel-craft, acondicionadas em sacos plásticos perfurados e armazenadas a 5°C por dois, quatro ou seis dias. Após o período de armazenamento a frio, as hastes foram colocadas em recipientes contendo 400mL de (1) água desionizada (controle), (2) solução de Flower® (Ecoplanet, SC) ou (3) solução preparada com 20g L-1 sacarose + 150mg L-1 ácido cítrico + 200mg L-1 de 8-HQC. As soluções foram trocadas a cada 48 horas, quando foi realizado o corte a 2cm na base da haste. Foi estabelecido o fim da vida de vaso quando as inflorescências apresentavam 50 por cento de abscisão ou murcha das flores. A longevidade das inflorescências diferiu com o tempo de armazenamento e com a solução de vaso utilizada. A maior vida de vaso foi obtida quando as hastes foram armazenadas por dois dias e, posteriormente mantidas em solução de sacarose+ácido cítrico+8-HQC. A solução de Flower® propiciou ganho de massa fresca e aumento do teor relativo de água das pétalas durante a reidratação. O uso apenas de água desionizada não foi eficiente em manter a qualidade das inflorescências de boca-de-leão, possivelmente pelo bloqueio dos vasos xilemáticos.
The goal of this research was to evaluate the effect of different solutions on rehydration and longevity of snapdragon inflorescences after dry cold storage. The stems were harvested with 6 to 7 open flowers and after 24 hours in water, they were wrapped in kraft paper, placed in perforated plastic bags and stored at 5oC for 2, 4 or 6 days. After the cold storage period, the stems were placed in jars containing 400mL of (1) deionized water, (2) Flower® (Ecoplanet, SC) or (3) 20g L-1 sucrose+150mg L-1 citric acid+200g L-1 8-HQC. The solutions were replaced every 48 hours when the base of the stem was cut (2cm). The end of the vase life was determined when the inflorescences presented 50 percent of abscission or flower wilting. The longevity of the inflorescences differed with the storage time and vase solution used. The longest vase life was obtained when the stems were stored for 2 days and placed in a solution of sucrose+citric acid+8-HQC afterwards. The solution of Flower® allowed gain of fresh mass and increase of relative water content of the petals during the rehydration. The use of deionized water was inefficient in maintaining the inflorescences quality, possible due to the occurrence of vascular occlusion.