|DONG, YU - Qinghai University|
|ZHI, HUANHUAN - Qinghai University|
Submitted to: Scientia Horticulturae
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/11/2023
Publication Date: 4/20/2023
Citation: Dong, Y., Zhi, H., Leisso, R.S. 2023. Physiological disorders, textural property, and cell wall metabolism of ‘Gem’ pears (Pyrus communis L.) affected by oxygen regimes and harvest maturity under controlled atmosphere storage. Scientia Horticulturae. 317:112067. https://doi.org/10.1016/j.scienta.2023.112067.
Interpretive Summary: Experiments examining the influence of harvest maturity and controlled atmosphere (CA) on storage longevity for 'Gem' pear indicated that less mature fruit and a low oxygen CA condition (1.0% oxygen with <0.5% carbon dioxide) enhance fruit quality and prolonged storage longevity relative to fruit stored in air or fruit stored under 2.2% oxygen and <0.5% carbon dioxide CA conditions.
Technical Abstract: The influences of harvest date and two controlled atmosphere (CA) regimes (1.0 % O2 with <0.5 % CO2 and 2.2 % O2 with <0.5 % CO2) on decay, abiotic disorders (including black speckles, superficial scald, and internal breakdown), storage and eating quality attributes, and cell wall metabolism were evaluated for ‘Gem’ pears stored at –1.1 °C for 6, 8, and 10 months. Earlier harvested pears (H1; 48.01 N flesh firmness (FF)) had lower rates of superficial scald and internal breakdown, and generally had superior storage quality relative to later harvested pears (H2; 42.19 N FF), especially in extended storage periods (8-10 months). Storage quality for air-stored fruit was marginal at and deteriorated after 6 months. Air-stored H1 fruit had high incidence of superficial scald, which affected 66.67 % of fruit at 6 months, and internal breakdown, which affected an 18.89 % of fruit at 6 months; incidence increased with storage duration for both disorders. CA regimes extended ‘Gem’ storage longevity to 8 to 10 months, with 1.0 % O2 resulting in lower incidence of both superficial scald and internal breakdown disorders relative to 2.2 % O2. For internal breakdown, greater susceptibility in later harvested fruit and increasing incidence with storage duration suggest fruit maturity and senescence influence development. Ethylene production rate (EPR) and respiration rate (RR) corroborated storage quality outcomes, with EPR and RR suppressed or delayed for CA-stored fruit relative to air-stored fruit. EPR and RR were generally higher in H2 relative to H1 for CA stored fruit. In principal components analysis, sensory evaluations were more closely associated with pectic polyuronides (including water-soluble polyuronides (WSP) and CDTA-soluble polyuronides (CSP)) and cell wall-modifying enzymes (including pectin methylesterase (PME), ß-galactosidase (ß-GAL), and a-arabinofuranosidase (a-ARF)) than FF before and after ripening, suggesting that the pectic polyuronides and cell wall-modifying enzymes better capture fruit textural qualities than FF in terms of eating quality.