scholarly journals Prestorage Conditioning and Diphenylamine Improve Resistance to Controlled-atmosphere-related Injury in ‘Honeycrisp’ Apples

HortScience ◽  
2014 ◽  
Vol 49 (1) ◽  
pp. 76-81 ◽  
Author(s):  
Carolina Contreras ◽  
Nihad Alsmairat ◽  
Randy Beaudry

‘Honeycrisp’ apples were found to be sensitive to injury from O2 and CO2 partial pressures typical of those in controlled-atmosphere (CA) storage. A preliminary study was conducted in 2008 to investigate the effect of the following O2/CO2 partial pressure (kPa) combinations: 1/0, 3/0, 1/3, 3/3, 21/3, 21/0 (air), and 21/0 with 1-methylcyclopropene (1-MCP; 1 μL·L−1) on CA-related injuries of 'Honeycrisp' during storage for 6 months at 3 °C. ‘Honeycrisp’ apples were found to be sensitive to an injury comprised of irregular-edged brown lesions in the cortex occasionally accompanied by the formation of lens-shaped voids. The symptoms are similar to CA-related injuries described for other apple cultivars and often characterized as a “CO2 injury.” Injury severity increased as O2 declined and as CO2 increased and was evident within the first month of storage. During 2009, 2010, and 2011, a study was conducted to evaluate options for avoiding injury during CA storage for this cultivar. Fruit were conditioned at 3, 10, and 20 °C for 5 days and then exposed to the following O2/CO2 partial pressure combinations: 3/0, 3/3, 21/0 (regular air); 3/3 with diphenylamine (DPA) drench (1 g·L−1); and 21/0 with 1-MCP (1 μL·L−1). Injury severity declined as the temperature of the prestorage conditioning period increased; holding fruit for 5 days at 20 °C almost completely eliminated the disorder. The antioxidant DPA also provided nearly complete control of CA injury. 1-MCP, although not studied in conjunction with a modified atmosphere, was found to cause no injury in air storage and may provide an alternative to CA storage and avoid the risk of CA injury for ’Honeycrisp’. The relationship between disorder development and growing degree-days, rainfall, and maturity indexes was studied. Ethylene was the only factor with a significant linkage to the development of CA injury (R2 = 0.35; P = 0.0043). Suggestions for handling of ‘Honeycrisp’ for extended storage are presented.

1991 ◽  
Vol 6 (1) ◽  
pp. 92-96 ◽  
Author(s):  
Katsumi Murase

The deposition process at 500 °C with SiH4–GeH4–B2H6–He mixtures, which yields the amorphous Si–Ge–B alloy, was studied. Although in crystalline Si and Ge the maximum B content is limited to the solid solubility, any amount of B can uniformly be contained in amorphous Si–Ge–B. Thus, films with a B content up to 64 at.% have been prepared. The deposition rate of atoms, defined as the number of atoms deposited in a unit time interval, is obtained for each element by analyzing the growth rate together with the composition and the mass density of the film. When the SiH4 and the B2H6 partial pressures are constant, the Si and the B deposition rates are almost independent of the GeH4 partial pressure. In contrast, the Si deposition rate increases remarkably as the B2H6 partial pressure increases, even when the SiH4 partial pressure is maintained constant. A simple model is proposed for explaining the relationship between the Si and the B deposition rates.


HortScience ◽  
1998 ◽  
Vol 33 (4) ◽  
pp. 719-722 ◽  
Author(s):  
H. John Elgar ◽  
Douglas M. Burmeister ◽  
Christopher B. Watkins

`Braeburn' apple (Malus ×domestica Borkh.) fruit can be susceptible to the development of an internal disorder called “`Braeburn' browning disorder” (BBD). Factors associated with development of this disorder were investigated. Susceptibility to injury was greater in fruit exposed to 2 or 5 kPa CO2 than to 0 kPa CO2 during storage. Susceptibility also increased with decreasing O2 partial pressure in the range of 5 to 1 kPa in the storage atmosphere. However, fruit stored in 1 kPa O2 remained firmer than those stored at higher partial pressures, regardless of CO2 level. BBD appeared to develop during the first 2 weeks of storage, and delays in air at 0 °C prior to controlled-atmosphere (CA) storage decreased incidence and severity of the disorder. The incidence of BBD was also reduced when the time to establish CA conditions was prolonged. We recommend that `Braeburn' apples be stored under CA conditions of ≤1.0 kPa CO2 and 3.0 kPa O2. Delayed application of CA for 2 weeks after fruit enter the coldstorage may also reduce development of BBD.


HortScience ◽  
2012 ◽  
Vol 47 (7) ◽  
pp. 886-892 ◽  
Author(s):  
Christopher B. Watkins ◽  
Jacqueline F. Nock

‘Honeycrisp’ is an apple [Malus xsylvestris (L.) Mill. var. domestica (Borkh.) Mansf.] that can be stored in air for several months, but the flavor becomes bland with prolonged storage. Controlled-atmosphere (CA) storage recommendations have not been made in some growing regions, however, because of the susceptibility of fruit to physiological disorders. In the first year of this study, we stored fruit from six orchards in O2 partial pressures (pO2) of 1.5, 3.0, and 4.5 kPa with 1.5 and 3.0 kPa pCO2. In the second year, we stored fruit from three orchards in three storage regimes (2.0/2.0, 3.0/1.5, 3.0/0.5 kPa O2/kPa CO2) with and without treatment of fruit with 1-methylcyclopropene (1-MCP) at the beginning and end of the conditioning regime (10 °C for 7 days) that is commercially used for ‘Honeycrisp’. CA storage had little effect on flesh firmness, soluble solids concentration (SSC), and titratable acidity (TA) over the range of pO2 and pCO2 tested. Greasiness was generally lower in fruit stored in lower pO2 and higher pCO2. Susceptibility of fruit to core browning and senescent breakdown varied between years, but a high incidence of internal CO2 injury in fruit from some orchards occurred in both years. 1-MCP treatment decreased internal ethylene concentration (IEC) and sometimes maintained TA but had little effect on firmness and SSC. Senescent breakdown and core browning incidence were reduced by 1-MCP treatment where orchard susceptibility to these disorders was high. However, 1-MCP treatment sometimes increased internal CO2 injury, especially if treatment occurred at the beginning of the conditioning period. CA storage cannot be recommended for storage of New York-grown ‘Honeycrisp’ apples until management of CO2 injury can be assured.


2014 ◽  
Vol 789 ◽  
pp. 466-470
Author(s):  
Qing Hao Shi ◽  
Bing Ying Wang ◽  
Bin Zhao

The corrosion mechanism of organic silicon modified polyurea composite coating under different CO2 partial pressures was studied using high-temperature autoclave, combined with scanning electron microscopy (SEM), adhesion tests and electrochemical impedance spectroscopy (EIS) technology. The experimental results showed that: there was no corrosion product formed on the surface of coating sample after high-temperature high-pressure corrosion test, and with the increasing of CO2 partial pressure, the coating adhesion and impedance values decline increases. Moreover CO2 partial pressure increases accelerated the failure process of polyurea composite coating system.


1986 ◽  
Vol 71 ◽  
Author(s):  
G.J. Van Der Kolk ◽  
M.J. Verkerk

AbstractAl was evaporated at oxygen partial pressures, PO2, varying between 10−7 and 10−4 Pa on substrates of silicon nitride. The substrate temperature was varied between 20 °C and 250°C. The films were annealed at temperatures up to 500°C.For Al films deposited at 20°C, it was found that the average grain size decreases with increasing oxygen partial pressure. After annealing recrystallization was observed. The relative increase of grain size was less for higher values of pO2. Annealing gave rise to a broad grain size distribution.For Al films deposited at 250°C, the presence of oxygen caused the growth of rough inhomogeneous films. This inhomogeneous structure remained during annealing.


1998 ◽  
Vol 13 (12) ◽  
pp. 3580-3586 ◽  
Author(s):  
A. L. Crossley ◽  
J. L. MacManus-Driscoll

A detailed study has been made of the control and optimization of partial melting of dipcoated Bi2Sr2Ca1Cu2O8+δAg0.1 (Bi-2212) tapes using reduced oxygen partial pressures. A coulometric titration technique has been employed to vary the oxygen partial pressure in a region of the phase diagram corresponding to binary melting, and the amount of partial melting has been quantified. Using this information, tapes have been processed using both isothermal and isobaric techniques. An optimum processing route was determined which combined isothermal and isobaric processes. Highly aligned material at the point of optimum melting was obtained.


2001 ◽  
Vol 91 (1) ◽  
pp. 77-83 ◽  
Author(s):  
H. Scherm ◽  
A. T. Savelle ◽  
P. L. Pusey

The relationship of cumulative chill-hours (hours with a mean temperature <7.2°C) and heating degree-days (base 7.2°C) to carpogenic germination of pseudosclerotia of Monilinia vaccinii-corymbosi, which causes mummy berry disease of blueberry, was investigated. In two laboratory experiments, pseudosclerotia collected from rabbiteye blueberry in Georgia were conditioned at 5 to 6°C for 26 to 1,378 h prior to placement in conditions favorable for germination and apothecium development. The number of chill-hours accumulated during the conditioning period affected the subsequent proportion of pseudosclerotia that germinated and produced apothecia, with the greatest incidence of carpogenic germination occurring after intermediate levels of chilling (≈700 chill-hours). The minimum chilling requirement for germination and apothecium production was considerably lower than that reported previously for pseudo-sclerotia from highbush blueberry in northern production regions. The rate of carpogenic germination was strongly affected by interactions between the accumulation of chill-hours and degree-days during the conditioning and germination periods; pseudosclerotia exposed to prolonged chilling periods, once transferred to suitable conditions, germinated and produced apothecia more rapidly (after fewer degree-days had accumulated) than those exposed to shorter chilling periods. Thus, pseudosclerotia of M. vaccinii-corymbosi are adapted to germinate carpogenically following cold winters (high chill-hours, low degree-days) as well as warm winters (low chill-hours, high degree-days). Results were validated in a combined field-laboratory experiment in which pseudosclerotia that had received various levels of natural chilling were allowed to germinate in controlled conditions in the laboratory, and in two field experiments in which pseudosclerotia were exposed to natural chilling and germination conditions. A simple model describing the timing of apothecium emergence in relation to cumulative chill-hours and degree-days was developed based on the experiments. The model should be useful for better timing of field scouting programs for apothecia to aid in management of primary infection by M. vaccinii-corymbosi.


1985 ◽  
Vol 58 (4) ◽  
pp. 1143-1147 ◽  
Author(s):  
F. L. Powell ◽  
F. A. Lopez ◽  
P. D. Wagner

We have detected acetone in several brands of heparin. If uncorrected, this leads to errors in measuring acetone in blood collected in heparinized syringes, as in the multiple inert gas elimination technique for measuring ventilation-perfusion ratio (VA/Q) distributions. Error for acetone retention [R = arterial partial pressure-to-mixed venous partial pressure (P-V) ratio] is usually small, because R is normally near 1.0, and the error is similar in arterial and mixed venous samples. However, acetone excretion [E = mixed expired partial pressure (P-E)-to-P-V ratio] will appear erroneously low, because P-E is accurately measured in dry syringes, but P-V is overestimated. A physical model of a homogeneous alveolar lung at room temperature and without dead space shows: the magnitude of acetone E error depends upon the ratio of blood sample to heparinized saline volumes and acetone partial pressures, without correction, acetone E can be less than that of less soluble gases like ether, a situation incompatible with conventional gas exchange theory, and acetone R and E can be correctly calculated using the principle of mass balance if the acetone partial pressure in heparinized saline is known. Published data from multiple inert gas elimination experiments with acetone-free heparin, in our labs and others, are within the limits of experimental error. Thus the hypothesis that acetone E is anomalously low because of physiological mechanisms involving dead space tissue capacitance for acetone remains to be tested.


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