removal from CA before 1-MCP treatment. This same study found little effect of 1-MCP on ‘Empire’ and ‘Delicious’ apples when the treatment followed air storage instead of CA. DeLong et al. (2004) found no effect of an additional 1-MCP application after 4
Jennifer DeEll and Behrouz Ehsani-Moghaddam
Elena de Castro, William V. Biasi, and Elizabeth J. Mitcham
had been treated with 1-MCP at harvest, very low concentrations of ethylene were detected in both 1 and 3 KPa CO 2 ( Fig. 5B ). Fruit softened during air storage, and flesh firmness was statistically lower after only 2 months for fruit harvested at
Don C. Elfving, Stephen R. Drake, A. Nathan Reed, and Dwayne B. Visser
20 °C in a sealed chamber with a circulation fan while the other fruit samples were maintained in cold storage. After exposure to 1-MCP, all stored fruit were placed in either air storage at 1 °C for 50 to 60 d or controlled-atmosphere (CA) storage [1
Jennifer R. DeEll and Behrouz Ehsani-Moghaddam
incidence of soft scald in ‘Honeycrisp’ apples after 6 months of air storage at 0 or 3 °C in 2008 ( Table 3 ). The highest incidences of soft scald were observed in fruit from the second harvest that were stored at 0 °C, with an average of 46% incidence in
William C. Kazokas and Jacqueline K. Burns
Mature and immature `Valencia' orange [Citrus sinensis (L.) Osbeck] and immature `Valencia' orange and `Tahiti' lime (Citrus latifolia Tan.) fruit with attached pedicels were treated with 8 μL·L-1 ethylene for periods up to 24 hours. Endo-β-1,4-glucanase (cellulase) activity and gene expression were determined in fruit abscission zones during and after ethylene exposure. Cellulase activities were not detected in mature `Valencia' orange and immature `Tahiti' lime fruit abscission zones immediately following harvest and after 6 hours of ethylene treatment. After 12 hours of ethylene treatment, cellulase activity increased and was highest after 24 hours. Cellulase gene expression preceded the rise in cellulase activity and was detectable after 6 hours of ethylene treatment, but then declined after 12 hours. Following transfer to air storage, abscission zone cellulase activity in mature `Valencia' fruit remained high, whereas activity in immature `Tahiti' fruit declined. After 168 hours air storage, activity in abscission zones of mature `Valencia' fruit decreased slightly, but activity in abscission zones of immature `Tahiti' lime fruit increased to the highest level. Expression of abscission zone cellulase gene Cel-a1 in abscission zones of mature `Valencia' fruit markedly increased after transfer to air and was highest after 48 hours air storage. Cel-a1 expression returned to low levels after 168 hours of air storage, but expression of cellulase gene Cel-b1 remained at low levels throughout the air storage period. Expression of Cel-a1 and Cel-b1 declined in fruit abscission zones of immature `Valencia' and `Tahiti' lime fruit upon transfer to air. After 168 hours of air storage, expression of Cel-a1 again rose to high levels but Cel-b1 remained low. The results suggest that differences in cellulase activity and gene expression measured in mature and immature fruit abscission zones during ethylene treatment and subsequent air storage may, in part, explain the differential response of mature and immature fruit to abscission agents.
Carolina Contreras, Nihad Alsmairat, and Randy Beaudry
low O 2 and/or elevated CO 2 and to evaluate the influence of prestorage conditioning and DPA treatment on the severity of CA injury of ‘Honeycrisp’. A secondary objective was to evaluate whether the use of 1-MCP in air storage, as an alternative to
Valeria Sigal Escalada and Douglas D. Archbold
Amsterdam, The Netherlands Plotto, A. McDaniel, M.R. Mattheis, J.P. 1999 Characterization of ‘Gala’ apple aroma and flavor: Differences between controlled atmosphere and air storage J. Amer. Soc. Hort. Sci. 124
Ahmed F. El-Shiekh and David H. Picha
Peaches stored in air for 40 days at OC developed severe internal breakdown and poor quality after transferring them to 20C to ripen. Comparable fruit stored under controlled atmosphere (1% O2 + 5% CO2) and then ripened at 20C had no breakdown and retained good quality. Fruit stored under CA had less reducing sugars but more sucrose than air stored fruit. Fruit pH increased and titratable acidity decreased over a 40 day storage period. Citric acid increased slightly while malic acid decreased during storage. Little or no differences in overall acidity and individual organic acids existed between CA and air storage. Little or no change in individual phenolic acid content occurred during storage or between CA and air storage. Internal color darkened and became redder with storage. CA stored fruit was significantly firmer than air stored fruit. Sensory evaluation indicated CA stored fruit was more acidic, sweeter, and had better overall flavor than air stored fruit.
D.C. Elfving and E.C. Lougheed
In three trials over 3 years, foliar BA applications for fruitlet thinning of `Empire' apple (Malus domestica Borkh.) trees produced small and inconsistent effects on flesh firmness at harvest and after air storage. Soluble solids concentrations at harvest and after air storage were consistently increased by BA alone or together with GA4+7 [Promalin (PR)], and were also increased by CB in one trial. Starch hydrolysis was slightly delayed by BA applications in 1990. Ethylene evolution at harvest was increased by NAA in 1988 and slightly increased by PR applied 29 days after full bloom (DAFB) in 1990, while poststorage ethylene evolution was stimulated by BA and PR treatments in 1990 except BA at 29 DAFB. Incidence of poststorage disorders was low and largely uninfluenced by thinning treatments. Chemical names used: N-(phenylmethyl)-1H-purine-6-amine [benzyladenine (BA)]; BA plus gibberellins A4 and A7 (GA 4+7) [Promalin (PR)]; 1-naphthaleneacetic acid (NAA); 1-naphthalenyl methylcarbamate [carbaryl (CB)].
Sylvia M. Blankenship, Michael Parker, and C. Richard Unrath
`Fuji' apples (Malus domestica Borkh.) were harvested at three maturities for three consecutive seasons. Fruit firmness, soluble solids concentration, starch—iodine index (SI), and internal ethylene concentration were measured at harvest. Fruit were stored in 0 °C air storage for 8 months. Fruit firmness and other maturity indices were measured monthly during storage. Using a stepwise regression procedure, harvest maturity indices were used to predict firmness after air storage. When all maturity indices measured were represented in the model, R 2 = 0.29, 0.34, and 0.26 at 4, 6, and 8 months, respectively. Use of only SI and fruit firmness in the model gave R 2 values of 0.25, 0.29, and 0.24 for 4, 6, and 8 months, respectively. Although R 2 values were low, they were highly significant. The model using fruit firmness and SI resulted in the best fit. Thus, an equation was developed using months of air storage, firmness, and SI at harvest. Actual firmness values correlated fairly well with predicted firmness values, usually within ≈5 N. On Washington apples, predicted values were 4.3 and 3.7 N too low compared to actual firmness values after 3 or 5 months' storage. In 1993, when predicted and actual firmness values were compared for Pennsylvania apples, predicted values ranged from 2.6 to 8.3 N too high after 3 months' storage, depending on harvest date. In 1994, Pennsylvania fruit stored 4 months had predicted values 0.5 N too high to 6.3 N too low, depending on harvest date. It may be possible to develop and refine models for an apple variety that would be applicable to several regions.