Boric acid as a potential substitute for conventional ethylene antagonists in mitigating postharvest flower senescence of Digitalis purpurea

• Published in: Ornamental Horticulture (Campinas) 2021-12, Vol.27 (4), p.516-525
• Main Authors: Farooq, Sumira, Haq, Aehsan ul, Lone, Mohammad Lateef, Altaf, Foziya, Parveen, Shazia, Tahir, Inayatullah
• Format: Article
• Language: English
• Subjects: AGRONOMY; Flower longevity; lipoxygenase; senescence; sugars
• ISSN: 2447-536X; 2447-536X
• DOI: 10.1590/2447-536x.v27i4.2374

Abstract In the floriculture industry, postharvest senescence is one of the glaring challenges restricting the marketability of cut flowers. Hence, maintaining good quality of cut flowers and extending flower longevity are considered to be the most crucial factors in the cut flower trade. Therefore, to gain better understanding of the specific physiological and biochemical aspects of petal senescence we conducted an experiment to evaluate the efficacy of Boric acid (BA) on flower longevity in excised flowers of Digitalis purpurea L. Isolated buds were harvested at stage IV i.e, 1 day before anthesis and divided into 5 sets, with one set of buds held in distilled water (DW) designated as control. The other 4 sets were supplemented with 24h pulse treatment of different concentrations of BA viz., 50, 100, 150 and 200 µM. The application of BA at 150 µM concentration was found to be most effective in increasing flower longevity by about 4 days as compared to control. The enhanced longevity coincided with higher values of floral diameter, fresh mass, dry mass and solution uptake. Flowers with delayed senescence also retained higher soluble proteins, sugars and phenols in addition to lower bacterial density compared to control. Moreover, this ameliorated flower longevity has also been shown to be positively associated with increased activities of various antioxidant enzymes viz., superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) and reduced activity of lipoxygenase (LOX). Resumo Na indústria da floricultura, a senescência pós-colheita é um dos desafios que restringe a comercialização das flores de corte. Portanto, manter a boa qualidade das flores de corte e prolongar a longevidade das flores são considerados os fatores mais importantes no comércio de flores de corte. Portanto, para obter uma melhor compreensão dos aspectos fisiológicos e bioquímicos específicos da senescência das pétalas, conduzimos experimento para avaliar a eficácia do ácido bórico (BA) na longevidade das flores em flores cortadas de Digitalis purpurea L. Botões isolados foram colhidos no estágio IV, ou seja, 1 dia antes da antese e dividido em 5 conjuntos, sendo um conjunto de gemas mantido em água destilada (DW) designado como controle. Os outros 4 conjuntos foram suplementados com tratamento de pulsing de 24 horas de diferentes concentrações de BA (50, 100, 150 e 200 µM). A aplicação de BA na concentração de 150 µM foi considerada mais eficaz no aumento da longevida