Resumen Introducción: ‘Perla’ y ‘Mexicano’ son variedades de nardo cultivadas de México que presentan potencial para su comercialización y exportación; sin embargo, no se han evaluado soluciones conservadoras que incrementen su vida útil. Objetivo: Determinar los cambios físicos, fisiológicos y químicos que ocurren en nardo en poscosecha cuando se aplican diferentes soluciones conservadoras. Metodología: Espigas de nardo ‘Mexicano’ y ‘Perla’, con dos flores basales abiertas, se colocaron en soluciones conservadoras (Crystal®, sacarosa [Sac] + ácido cítrico [AC] + hidroxiquinoleína citrato [HQC] y ácido ascórbico [AAsc]). Se mantuvo un grupo de espigas como testigo, y en todos los casos se evaluaron variables destructivas y no destructivas en poscosecha. Resultados: El peso fresco relativo y el consumo de agua aumentaron con las soluciones conservadoras en ambos cultivares. La apariencia en ‘Perla’ fue excelente por 5 días con Crystal®. En ‘Mexicano’ abrieron más flores con Crystal® y Sac + AC + HQC, mientras que en ‘Perla’ fue con AAsc y Crystal®. La respiración en ‘Mexicano’ fue alta con Sac + AC + HQC, y en ‘Perla’ fue baja con AAsc. En ‘Perla’, la mayor actividad específica de superóxido dismutasa se detectó con AAsc y Crystal®. Limitaciones del estudio: Los resultados son válidos sin realizar aplicaciones previas de soluciones pulso o hidratantes en las variedades de nardo evaluadas. Originalidad: Es el primer estudio donde se evalúa el comportamiento poscosecha de dos variedades de nardo mexicanas en soluciones conservadoras. Conclusiones: En ‘Mexicano’ y ‘Perla’ se pueden utilizar las soluciones Crystal® y AAsc para mantener la calidad por mayor tiempo en florero.

Abstract Introduction: ‘Perla’ and ‘Mexicano’ are varieties of tuberose grown in Mexico that have potential for commercialization and export; however, no preservative solutions have been evaluated to increase their shelf life. Objective: To determine physical, physiological, and chemical changes that occur in postharvest tuberose when different preservative solutions are applied. Methodology: Tuberose flower spikes of varieties ‘Mexicano’ and Perla, with two open basal flowers, were placed in preservative solutions (Crystal®, sucrose [Sac] + citric acid [CA] + hydroxyquinoline citrate [HQC] and ascorbic acid [AAsc]). A group of tuberose flower spikes was kept as control, and in all cases destructive and non-destructive variables were evaluated during postharvest. Results: Relative fresh weight and water consumption increased with preservative solutions in both varieties. The appearance of the ‘Perla’ variety was excellent for 5 days with Crystal®. The ‘Mexicano’ variety had more open flowers with Crystal® and Sac + AC + HQC, while the ‘Perla’ variety had the same result with AAsc and Crystal®. Respiration in the ‘Mexicano’ variety was high with Sac + AC + HQC, and in the case of ‘Perla’ variety, respiration was low with AAsc. The highest specific superoxide dismutase activity was detected with AAsc and Crystal® for ‘Perla’ variety. Study limitations: The results are valid without previous applications of pulse or hydrating solutions in tuberose varieties evaluated. Originality: This is the first study where the postharvest behavior of two Mexican tuberose varieties is evaluated in preservative solutions. Conclusions: ‘Mexicano’ and ‘Perla’ varieties can use Crystal® and AAsc solutions to maintain the quality for longer time in vase.

Resumo O efeito do pulsing no comportamento pós-colheita de angélica foi avaliado para as cultivares ‘Mexican Single’ e ‘The Pearl’. As inflorescências de ambas foram colhidas com 1 ou 2 de seus botões basais abertos e tratadas com 20% de sacarose e 200 mg de citrato de hidroxiquinolina (sacarose + HQC). O pulsing aumentou o peso relativo fresco das inflorescências, embora a captação de água na ‘The Pearl’ tenha sido maior. Após 5 dias, a qualidade visual foi classificada como ‘excelente’ e ‘boa’ em ‘Mexican Single’ e ‘The Pearl’, respectivamente, e o maior número de flores abertas e senescentes ocorreu no último pulsing. Os valores de CIE L*C*h e açúcares totais aumentaram entre as flores tratadas de ‹The Pearl›, enquanto taxas mais altas de respiração ocorreram na testemunha de ‹Mexican Single›. A atividade da catalase foi constante em ‹The Pearl›, embora as atividades de superóxido dismutase e peroxidase tenham sido mais altas e semelhantes, respectivamente, às da ‹Mexican Single›. Essas diferenças no comportamento físico, fisiológico e enzimático são importantes a serem consideradas ao desenvolver estratégias de conservação e manejo pós-colheita, específicas para cada variedade.

Abstract The effect of pulsing on the postharvest behavior of cut tuberose was evaluated in the cultivars ‘Mexican Single’ and ‘The Pearl’. Spikes of both were harvested with 1 or 2 of their basal buds open and treated with 20% sucrose and 200 mg of hydroxyquinoline citrate (sucrose + HQC). Pulsing increased the relative fresh weight of spikes, although water uptake in ‘The Pearl’ was greater regardless. After 5 days, visual quality was scored as ‘excellent’ and ‘good’ in ‘Mexican Single’ and ‘The Pearl’, respectively, and the greatest number of open and of senescent flowers occurred in the latter independent of pulsing. CIE L*C*h values and total sugars increased more noticeably among pulsed florets in ‘The Pearl’, whereas higher rates of respiration occurred in the unpulsed spikes of ‘Mexican Single’. Catalase activity was constant in ‘The Pearl’, although superoxide dismutase and peroxidase activities were higher and similar to, respectively, those of ‘Mexican Single’. These differences in physical, physiological and enzymatic behavior are important to consider when developing postharvest conservation and management strategies that are specific for each variety.

Abstract Tuberose (Polianthes tuberosa) ‘Mexicano’ and ‘Perla’ spikes, were harvested with 5 or 1 open basal flowers, and then treated with hydrating solutions containing gibberellic acid, benzyladenine, amino oxyacetic acid, citric acid, sucrose or hydroxyquinoline citrate, to evaluate postharvest physical, chemical and physiological changes, for a later technological development to increase the useful life of this ornamental plant. We used a radomentized experimental design, with a spike as the experimental unit and six or eight repetitions. Our results indicate that in both varieties, the relative fresh weight and water consumption and the number of open flowers increased, while respiration and total sugars decreased, when treated with HS containing AC or BA. The appearance was good for five days in ‘Mexicano’ spikes hydrated with AC or BA + Sac, while in ‘Perla’, for seven days in all HS-applied treatments. Peroxidase, catalase and superoxide dismutase enzymatic activities were high in control spikes and low when hydrated with AC or BA. In conclusion, hydration with AC or BA improves the metabolism and quality of ‘Mexicano’ and ‘Perla’ spikes.

Resumen Espigas de nardo (Polianthes tuberosa) ‘Mexicano’ y ‘Perla’ con 5 ó 1 flores basales abiertas, se trataron con soluciones hidratantes (SH) conteniendo ácido gibérelico (AG3), benciladenina (BA), ácido amino-oxiácetico (AOA), ácido cítrico (AC), sacarosa (Sac) o hidroxiquínoleina citrato (HQC) con el objetivo de evaluar los cambios físicos, químicos y fisiológicos durante poscosecha, para posteriormente desarrollar tecnologías que incrementen la vida útil de esta especie ornamental. Se utilizó un experimento completamente al azar, la unidad experimental fue una espiga con seis a ocho repeticiones. Los resultados indican que el peso fresco relativo, consumo de agua y número de flores abiertas se incrementó; la respiración y azúcares totales disminuyeron en ambas variedades, cuando se aplicaron SH con AC o BA. La apariencia fue buena por cinco días en ‘Mexicano’ en las espigas hidratadas con AC o BA+ Sac y en ‘Perla’ por siete días en todos los tratamientos donde se aplicó SH. La actividad de peroxidasa, catalasa y superóxido dismutasa fue mayor en las espigas testigo y menor cuando se aplicaron las SH con BA + Sac o AC. En conclusión, la hidratación con AC ó BA mejoran el metabolismo y calidad de las espigas de nardo ‘Mexicano’ y ‘Perla’ en poscosecha.