New technology of protecting apple fruits from bitter pit and other physiological diseases during storage

Abstract

The work was performed in the I. V. Michurin Federal Scientifi c Center (Tambov region, Russia) in 2015-2018. The fruits of Sinap Orlovsky variety with high susceptibility to bitter pit, medium – to superfi cial scald and CO2 -skin injuries were used. The main post-harvest strategy of protecting fruits from bitter pit (BP) is storage in a controlled atmosphere (CA), short-term low oxygen storage (10 days, O2<1 %) reduces losses from scald and BP, but does not provide protection from diseases of varieties with high susceptibility; post-harvest treatment with ethylene biosynthesis inhibitor (1-MCP) provides protection from scald, but has an ambiguous effect on the development of BP, and may increase the degree of disease appearance. The purpose of the research is the development of innovative technology of managing of bitter pit and other post-harvest pathological diseases. In the experiment, the control and 1-MCP-treated fruits were stored at 0 + 1 °C under regular (RA) and controlled atmosphere (CA) conditions: CA-1 (CO2 – 1.2-1.5 %, O2 – 1.2-1.5 %), CA-2 (СО2<0.1 %, О2 – 1.2-1.5 %), under conditions of short (10 days) post-harvest impact of controlled factors: temperature 18-20 °С, О2 – 1.2-1.5 %, CO2<0.1 % and further storage in regular atmosphere (LO2 ). Ethylene, α-farnesen and its oxidation products (CТ281), phenolic compounds were determined in fruits, losses from bitter pit, scald, CO2 -skin injuries, quality (fi rmness) were estimated. 1-MCP-treatment ensured a low level of ethylene and CT281 accumulation in fruits, protection from scald, preservation of fi rmness in all variants of fruit storage, with maximum effi ciency of variants CA-2, CA-1 and LO2 . Fruit protection from bitter pit was provided by CA-2 technology, a signifi cant reduction of losses – LO2 . When using the technology of CA-2, losses from CO2 -skin injuries, noted in the conditions of CA-1, were excluded. The maximum efficiency of protection of fruits from BP, scald, CO2 -injuries is provided by the developed technology CA-2 (CO2<0.1 %, O2 — 1.2-1.5 %).