?Bartlett? pear ethylene production post storage depends on storage time and 1-MCP concentration

Repeated low-dose 1-MCP-applications were evaluated during cold storage of ?Bartlett? pear fruit to overcome long-term ripening inhibition of a high dose 1-MCP treatment at harvest. Fruit were exposed to 1-MCP at 0, 0.42, 4.2 or 42 ?mol m?3 at harvest in year one, and to 0, 0.42 or 42 ?mol m?3 in year two, and then stored in air at 0.5 ?C. In year two, fruit exposed to 1-MCP at 0.42 ?mol m?3 at harvest were retreated during cold storage once (after 38 days) or twice (after 38 and 68 days), when ethylene production in samples removed from cold storage exceeded 0.014 ?mol kg?1 s?1 within 7 days at 20 ?C. 1-MCP was re-applied once at 0.42 or 4.2 ?mol m?3 or twice at 0.42 or 4.2 then 42 ?mol m?3. In year one, fruit treatment at harvest with 4.2 or 42 ?mol m?3 1-MCP provided similar ripening delay during 120 days in storage followed by 7 days at 20 ?C, while fruit treated with 0.42 ?mol m?3 1-MCP was not different from the control. In year two, fruit treated at harvest with 0.42 ?mol m?3 1-MCP and retreated with 0.42 ?mol m?3 (when ethylene production was already high) did not delay subsequent fruit ripening. Fruit treated at harvest with 42 ?mol m?3 1-MCP or with 0.42 ?mol m?3 at harvest and then +4.2 + 42, had similar peel yellow color, TA and SSC, but higher firmness after 180 days storage, compared to control fruit after 60 days storage. After 180 days storage, the severity of superficial scald, senescent scald and core browning on fruit treated only at harvest with 42 ?mol m?3 were lower than on control fruit and similar to on fruit treated with 0.42 ?mol m?3 at harvest and then retreated with +4.2 + 42. Therefore, a low dose application of 1-MCP at harvest followed by reapplication with higher doses based on fruit ethylene production capacity after removal from cold storage can extend ?Bartlett? pear storage life while allowing ripening to occur after mid-term storage. The efficiency of this procedure will depend on timing and 1-MCP reapplication concentration. SourcesManaging ?Bartlett? pear fruit ripening with 1-methylcyclopropene reapplication during cold storageLuiz C. Argenta (a), James P. Mattheis (b), Xuetong Fan (c), Cassandro V.T. Amarante (d)Postharvest a EPAGRI, Esta??o Experimental, 89500-000 Ca?ador, SC, Brazilb USDA, ARS Tree Fruit Research Laboratory, 1104 N. Western Avenue, Wenatchee, WA 98801, USAc USDA, ARS ERRC, 600 E. Mermaid Lane, Wyndmoor, PA 19038, USAd UDESC, Centro de Ci?ncias Agroveterin?rias, Avenida Luiz de Cam?es, 2090, CEP 88520-000 Lages, SC, BrazilPostharvest Biology and Technology, Volume 113, March 2016, Pages 125?130Picture by www.lilsnappers.com