scholarly journals Ethylene and Lipoxygenase In Relation to Afterripening of Dormant NC-13 Peanut Seeds1,2

1985 ◽  
Vol 12 (1) ◽  
pp. 45-49 ◽  
Author(s):  
D. L. Ketring ◽  
H. E. Pattee
Keyword(s):  
Heat Treatment ◽  
Cold Storage ◽  
Ethylene Production ◽  
Sharp Increase ◽  
Gradual Increase ◽  
The Other ◽  
Immature Seeds ◽  
Positive Correlations ◽  
Mature Seeds

Abstract Following harvest, peanuts are usually subjected to a period of storage. During storage biochemical changes are known to occur. The objectives of this study were to determine the changes and relationship in ethylene production, germination, and lipoxygenase (LG) activity during cold storage of dormant NC-13 peanut seeds. Two seed lots (SL) were used: one grown in Oklahoma (SL80) and the other grown in N. Carolina (SL81). SL80 and SL81 were stored at 2 to 5 C for 193 and 242 days, respectively. Samples were taken at about 28-day intervals for determination of germination, ethylene production, and LG activity. Seeds of two and three maturities were tested for SL80 and SL81, respectively. As afterripening of stored seeds proceeded, ethylene production gradually increased, with the maximum at 48 hours of germination. Germination showed a concomitant gradual increase. Lipoxygenase activity of both seedlots was less for mature than for immature seeds and showed a sharp increase during storage at 2 to 5 C, particularly for immature seeds. After heat-treatment to break dormancy of sublots from SL81, there was a progessive increase in ethylene production and germination, but most notably for mature seeds. In contrast to ethylene production and germination, after heat-treatment LG activity declined. Linear correlation coefficient (r) values between ethylene production and germination were highly significant for mature seeds from SL80 at 48 and 72 hours of germination, but only at 72 hours for immature seeds. For SL81 as for SL80, significant positive correlations were found between ethylene production and germination. However, correlations between LG activity and the other variables were not significant except for mature seeds from SL81. Significant positive correlations for both ethylene production and germination with LG activity also existed for these seeds. But after heat-treatment these correlations no longer occurred. The data indicate that the metabolic processes related to ethylene production and germination are occurring simultaneously with those of LG activity. The possibility that metabolites from LG activity serve as substrates for ethylene production can not be precluded.

scholarly journals Effects of 1-Methylcyclopropene and Heat Treatments on Ripening and Postharvest Decay in `Golden Delicious' Apples

2003 ◽  
Vol 128 (1) ◽  
pp. 120-127 ◽  
Author(s):  
Robert A. Saftner ◽  
Judith A. Abbott ◽  
William S. Conway ◽  
Cynthia L. Barden
Keyword(s):  
Heat Treatment ◽  
Cold Storage ◽  
Ethylene Production ◽  
Titratable Acidity ◽  
Heat Treatments ◽  
Penicillium Expansum ◽  
Colletotrichum Acutatum ◽  
Peel Color ◽  
Golden Delicious ◽  
Force Profile

Prestorage heat, CA storage, and pre- and poststorage treatments with the ethylene action inhibitor, 1-methylcyclopropene (MCP), were tested for their efficacy at inhibiting fungal decay and maintaining quality in `Golden Delicious' apples [Malus sylvestris (L.) Mill. Yellow Delicious Group] stored 0 to 5 months at 0 °C and 7 days at 20 °C. Before storage in air at 0 °C, preclimacteric fruit were treated with either MCP at a concentration of 1 μL·L-1 for 17 hours at 20 °C, 38 °C air for 4 days, MCP plus heat, or left untreated. Some sets of untreated fruit were stored in a controlled atmosphere of 1.5 kPa O2 and 2.5 kPa CO2 at 0 °C while other sets were removed from cold storage in air after 2.5 or 5 months, warmed to 20 °C, and treated with 1 μL·L-1 MCP for 17 hours. Prestorage MCP, heat, MCP plus heat treatments and CA storage decreased decay severity caused by wound-inoculated Penicillium expansum Link, Botrytis cinerea Pers.:Fr., and Colletotrichum acutatum Simmonds (teleomorph Glomerella acutata J.C. Guerber & J.C. Correll sp.nov.). Poststorage MCP treatment had no effect on decay severity. Both prestorage MCP treatment and CA storage delayed ripening as indicated by better retention of green peel color, titratable acidity, and Magness-Taylor flesh firmness, and the reduced respiration, ethylene production rates, and volatile levels that were observed upon transferring the fruit to 20 °C. The prestorage MCP treatment delayed ripening more than CA storage. Following 5 months cold storage, the prestorage MCP treatment maintained the shape of the compression force/deformation curve compared with that of fruit at harvest, as did CA storage, but at a lower force profile. The heat treatment had mixed effects on ripening: it hastened loss of green peel color and titratable acidity, but maintained firmness and delayed increases in respiration, ethylene production and volatile levels following cold storage. The MCP plus heat treatment inhibited ripening more than heat treatment alone but less than MCP treatment alone. In one of 2 years, the MCP plus heat treatment resulted in superficial injury to some of the fruit. Results indicated that MCP may provide an effective alternative to CA for reducing decay severity and maintaining quality during postharvest storage of `Golden Delicious' apples. Prestorage heat to control decay and maintain quality of apples needs further study, especially if used in combination with MCP.

scholarly journals Ethylene production in apple infected by Gleosporium album Ostrw. at cold storage

2011 ◽  
Vol 33 (No. 1) ◽  
pp. 1-6
Author(s):  
J. Goliáš ◽  
A. Němcová ◽  
P. Mýlová
Keyword(s):  
Cold Storage ◽  
Ethylene Production ◽  
Canonical Correlation ◽  
Storage Temperature ◽  
Apple Fruit ◽  
Gas Analysis ◽  
Light Hydrocarbons ◽  
High Affinity ◽  
Headspace Gas

In ten cultivars of apple fruit, ethylene production expressed in μl/kg/h was determined. The cultivar Resista exhibited a higher ethylene production and can be differentiated from other cultivars. The production ranged from 4.2 ± 0.58 μl/kg/h in the case of Meteor cv. up to 131.6 ± 5.5 μl/kg/h in Resista cv. Infected fruit of Topaz cv. had a lower ethylene production at cold storage temperature (3°C) than some healthy fruit. All examined cultivars can be divided into three clusters. Discriminant analysis and canonical correlation analysis of the examined apple fruit led to the determination of healthy and infected fruit. Values of ethylene production were analyzed on intact fruit by using headspace gas analysis by CGC with thermal desorption technique. Carbosieve G was chosen as the adsorbent material for the traps due to its relatively high affinity for light hydrocarbons such as ethylene. For a full trap of ethylene in the enrichment column the sufficient amount of percolating gas is about 0.3 l.  

CHARACTERIZATION OF THE SINTERED Nd15Fe77B8 ALLOY

2011 ◽  
Vol 25 (06) ◽  
pp. 877-884
Author(s):  
L. HADJADJ
Keyword(s):  
Heat Treatment ◽  
Magnetic Properties ◽  
Optical Microscope ◽  
The Other ◽  
Average Value ◽  
Nd15fe77b8 Alloy

In this work the purpose is, in addition to the determination of microhardness, to get some information about the effect of heat treatment on the microstructure of the magnetic Nd 15 Fe 77 B 8 alloy. For this study we have used an optical microscope and an electronic microprobe. The results show that the structure of the Nd 2 Fe 14 B phase, which confers good mechanical and magnetic properties on the alloy, is well tetragonal, as mentioned in several works. The morphology, the concentration and the quantity of this phase depend on the temperature of annealing. The microhardness of the phase has an average value between those of the other involved phases.

CARBOHYDRATE METABOLISM OF McINTOSH APPLES DURING THEIR DEVELOPMENT ON TREE AND IN COLD STORAGE: PART 1. GENERAL TRENDS

1946 ◽  
Vol 24c (4) ◽  
pp. 126-144 ◽  
Author(s):  
G. Krotkov ◽  
V. Helson
Keyword(s):  
Carbohydrate Metabolism ◽  
Cold Storage ◽  
Sharp Increase ◽  
Sugar Content ◽  
Insoluble Residue ◽  
P Content ◽  
Three Stages ◽  
Apple Fruits

For two consecutive years, weekly samples of apples were taken during the development of fruits on the tree and in subsequent cold storage. Following determination of their respiration, the fruits of each sample were analysed for various forms of carbohydrates and also for their insoluble P content. The last constituent was assumed to represent the 'protoplasmic factor,' Six different physiological stages are distinguished during the ontogeny of apple fruits. These are based on changes in the direction and in the rates of metabolism of various carbohydrates. The first three stages are passed while apples are on tree; the next one is passed either partly or even completely in storage, depending on the date of picking; the last two are passed entirely in storage. At the beginning of storage there was observed a sharp increase in the sugar content or apples. Since there was no corresponding decrease in the alcohol insoluble residue, it was concluded that such sugars must come from some alcohol soluble substances.

scholarly journals Postharvest properties of ultra-late maturing peach cultivars and their attributions to Melting Flesh (M) locus: Re-evaluation of M locus in association with flesh texture

2020 ◽  
Author(s):  
Ryohei Nakano ◽  
Takashi Kawai ◽  
Yosuke Fukamatsu ◽  
Kagari Akita ◽  
Sakine Watanabe ◽  
...  
Keyword(s):  
Ethylene Production ◽  
Prunus Persica ◽  
Experimental Period ◽  
The Other ◽  
Sequencing Data ◽  
Peach Fruit ◽  
Endogenous Ethylene ◽  
The Common ◽  
Exogenous Ethylene

AbstractThe postharvest properties of two ultra-late maturing peach cultivars, ‘Tobihaku’ (TH) and ‘Daijumitsuto’ (DJ), were investigated. Fruit were harvested at commercial maturity and held at 25°C. TH exhibited the characteristics of normal melting flesh (MF) peach, including rapid fruit softening associated with an increase in endogenous ethylene production In contrast, DJ did not soften at all during three-week experimental period even though substantial ethylene production was observed. Fruit of TH and DJ were treated with 5000 ppm of propylene, an ethylene analog, continuously for seven days. TH softened rapidly whereas DJ maintained high flesh firmness in spite of an increase in endogenous ethylene production, suggesting that DJ but not TH lacked the ability to be softened in response to endogenous and exogenous ethylene/propylene. DNA-seq analysis showed that tandem endo-polygalacturonase (endoPG) genes located at melting flesh (M) locus, Pp-endoPGM (PGM) and Pp-endoPGF (PGF), were deleted in DJ. The endoPG genes at M locus are known to control flesh texture of peach fruit, and it was suggested that the non-softening property of DJ is due to the lack of endoPG genes. On the other hand, TH possessed an unidentified M haplotype that is involved in determination of MF phenotype. Structural identification of the unknown M haplotype, designated as M0, through comparison with previously reported M haplotypes revealed distinct differences between PGM on M0 haplotype (PGM-M0) and PGM on other haplotypes (PGM-M1). Peach M haplotypes were classified into four main haplotypes: M0 with PGM-M0; M1 with both PGM-M1 and PGF; M2 with PGM-M1; and M3 lacking both PGM and PGF. Re-evaluation of M locus in association with MF/non-melting flesh (NMF) phenotypes in more than 400 accessions by using whole genome shotgun sequencing data on database and/or by PCR genotyping demonstrated that M0 haplotype was the common haplotype in MF accessions, and M0 and M1 haplotypes were dominant over M2 and M3 haplotypes and co-dominantly determined the MF trait. It was also assumed on the basis of structural comparison of M haplotypes among Prunus species that the ancestral haplotype of M0 diverged from those of the other haplotypes before the speciation of Prunus persica.

Determination of Superoxide Free Radical Ion and Hydrogen Peroxide as Products of Photosynthetic Oxygen Reduction

1975 ◽  
Vol 30 (1-2) ◽  
pp. 53-57 ◽  
Author(s):  
Erich Elstner ◽  
Claus Stoffer ◽  
Adelheid Heupel
Keyword(s):  
Heat Treatment ◽  
Hydrogen Peroxide ◽  
Superoxide Dismutase ◽  
Free Radical ◽  
Oxygen Reduction ◽  
The Other ◽  
Keto Acids ◽  
Superoxide Free Radical ◽  
Photosynthetic Oxygen

Abstract Formation of Nitrite from Hydroxylamine in the presence of illuminated chloroplast lamellae is inhibited by superoxide dismutase but not by catalase, indicating that the superoxide free radical ion and not H2O2 is responsible for the oxidation of hydroxylamine. Decarboxylation of α-keto acids on the other hand is strongly inhibited by catalase but only slightly by superoxide dismutase. Light-dependent hydroxylamine oxidation and decarboxylation of α-keto acids can be used, therefor, as specific and sensitive probes for the determination of either the superoxide free radical ion or hydrogen peroxide, respectively. Photosynthetic oxygen reduction in the presence of ferredoxin, (monitored by the above method) yields both H2O2 and O2·-. The addition of an oxygen reducing factor (ORF, solubilized by heat - treatment of washed chloroplast lamellae) instead of ferredoxin, however, stimulates only the production of H2O2 , while O2·- - formation is not observed. The cooperation of ferredoxin and ORF during photosynthetic oxygen reduction by chloroplast lamellae apparently produces H2O2 not only by dismutation of O2·-, but also by a separate mechanism involving ORF.

scholarly journals Involvement of Ethylene in Development of Chilling Injury in Fresh-cut Tomato Slices during Cold Storage

2000 ◽  
Vol 125 (6) ◽  
pp. 736-741 ◽  
Author(s):  
Ji Heun Hong ◽  
Kenneth C. Gross
Keyword(s):  
Lycopersicon Esculentum ◽  
Cold Storage ◽  
Negative Correlation ◽  
Ethylene Production ◽  
Chilling Injury ◽  
The Other ◽  
Modified Atmosphere ◽  
Ethylene Concentration ◽  
Fresh Cut ◽  
Absorbent Pads

Experiments were conducted to determine if ethylene influences chilling injury, as measured by percentage of slices exhibiting water-soaked areas in fresh-cut tomato slices of `Mountain Pride' and `Sunbeam' tomato (Lycopersicon esculentum Mill.). Ethylene concentration in containers without ventilation significantly increased during storage at 5 °C, whereas little or no accumulation of ethylene occurred in containers with one or six perforations. Chilling injury was greatest for slices in containers with six perforations, compared to slices in containers with one perforation, and was over 13-fold greater than that of slices in control containers with no perforations. An experiment was also performed to investigate the effectiveness of including an ethylene absorbent pad in containers on subsequent ethylene accumulation and chilling injury. While ethylene in the no-pad controls increased continually during storage of both `Mountain Pride' and `Sunbeam' tomatoes at 5 °C under modified atmosphere conditions, no increase in accumulation of ethylene was observed in containers containing ethylene absorbent pads throughout storage. The ethylene absorbent pad treatment resulted in a significantly higher percentage of chilling injury compared with the no-pad control. In studies aimed at inhibiting ethylene production using AVG during storage of slices, the concentration of ethylene in control containers (no AVG) remained at elevated levels throughout storage, compared to containers with slices treated with AVG. Chilling injury in slices treated with AVG was 5-fold greater than that of controls. Further, we tested the effect of ethylene pretreatment of slices on subsequent slice shelf life and quality. In slices treated with ethylene (0, 0.1, 1, or 10 μL·L-1) immediately after slicing, ethylene production in nontreated controls was greater than that of all other ethylene pretreatments. However, pretreatment of slices 3 days after slicing resulted in a different pattern of ethylene production during storage. The rate of ethylene production by slices treated with 1 μL·L-1 ethylene 3 days after slicing was greater during storage than any of the other ethylene treatments. With slices pretreated with ethylene, both immediately and 3 days after slicing, the rate of ethylene production tended to show a negative correlation with chilling injury. Chemical name used: 1-aminoethoxyvinylglycine (AVG).

scholarly journals Postharvest Properties of Ultra-Late Maturing Peach Cultivars and Their Attributions to Melting Flesh (M) Locus: Re-evaluation of M Locus in Association With Flesh Texture

2020 ◽  
Vol 11 ◽  
Author(s):  
Ryohei Nakano ◽  
Takashi Kawai ◽  
Yosuke Fukamatsu ◽  
Kagari Akita ◽  
Sakine Watanabe ◽  
...  
Keyword(s):  
Ethylene Production ◽  
Prunus Persica ◽  
Experimental Period ◽  
The Other ◽  
Sequencing Data ◽  
Peach Fruit ◽  
Endogenous Ethylene ◽  
The Common ◽  
Exogenous Ethylene

The postharvest properties of two ultra-late maturing peach cultivars, “Tobihaku” (TH) and “Daijumitsuto” (DJ), were investigated. Fruit were harvested at commercial maturity and held at 25°C. TH exhibited the characteristics of normal melting flesh (MF) peach, including rapid fruit softening associated with appropriate level of endogenous ethylene production In contrast, DJ did not soften at all during 3 weeks experimental period even though considerable ethylene production was observed. Fruit of TH and DJ were treated with 5,000 ppm of propylene, an ethylene analog, continuously for 7 days. TH softened rapidly whereas DJ maintained high flesh firmness in spite of an increase in endogenous ethylene production, suggesting that DJ but not TH lacked the ability to be softened in response to endogenous and exogenous ethylene/propylene. DNA-seq analysis showed that tandem endo-polygalacturonase (endoPG) genes located at melting flesh (M) locus, Pp-endoPGM (PGM), and Pp-endoPGF (PGF), were deleted in DJ. The endoPG genes at M locus are known to control flesh texture of peach fruit, and it was suggested that the non-softening property of DJ is due to the lack of endoPG genes. On the other hand, TH possessed an unidentified M haplotype that is involved in determination of MF phenotype. Structural identification of the unknown M haplotype, designated as M0, through comparison with previously reported M haplotypes revealed distinct differences between PGM on M0 haplotype (PGM-M0) and PGM on other haplotypes (PGM-M1). Peach M haplotypes were classified into four main haplotypes: M0 with PGM-M0; M1 with both PGM-M1 and PGF; M2 with PGM-M1; and M3 lacking both PGM and PGF. Re-evaluation of M locus in association with MF/non-melting flesh (NMF) phenotypes in more than 400 accessions by using whole genome shotgun sequencing data on database and/or by PCR genotyping demonstrated that M0 haplotype was the common haplotype in MF accessions, and M0 and M1 haplotypes were dominant over M2 and M3 haplotypes and co-dominantly determined the MF trait. It was also assumed on the basis of structural comparison of M haplotypes among Prunus species that the ancestral haplotype of M0 diverged from those of the other haplotypes before the speciation of Prunus persica.

scholarly journals Cultivar Variation in Response to AVG and Heat Treatments for Sustaining Apple Fruit Quality in Cold Storage

HortScience ◽  
2004 ◽  
Vol 39 (4) ◽  
pp. 781D-782
Author(s):  
Valeria Sigal Escalada* ◽  
Douglas D. Archbold
Keyword(s):  
Heat Treatment ◽  
Respiration Rate ◽  
Fruit Quality ◽  
Cold Storage ◽  
Ethylene Production ◽  
Apple Fruit ◽  
Heat Treatments ◽  
Apple Cultivars ◽  
Postharvest Ripening

To determine if apple cultivars vary in their response to aminoethoxyvinylglycine (AVG) and heat treatment, alone or combined, postharvest ripening traits and storability of treated Lodi, Senshu, Red Delicious and Fuji have been studied. An aqueous solution of AVG was applied 4 weeks before harvest of each cultivar at 124 g·ha-1 a.i. Control and AVG-treated fruit were heated at 38 °C for 4 days. Fruit were ripened at ambient temperature immediately harvest and treatment, or after storage at 4 °C for 30 days. AVG reduced firmness loss in all but Fuji apples immediately after harvest, and that effect was maintained in Senshu and Red Delicious apples after 30 days in cold storage. All AVG-treated fruit showed a reduction in respiration rate and ethylene production immediately after harvest as well as after removal from cold storage. Heat treatment alone prevented firmness loss in Senshu and Red Delicious cultivars, and slightly reduced respiration rate of Lodi and Senshu apples. Ethylene production was clearly lower in heated compared to non-heated fruit in Senshu, Red Delicious and Fuji. After cold storage, AVG and heat treatments combined decreased flesh firmness loss of Lodi apples, reduced respiration in Lodi and Fuji apples, and highly repressed ethylene production of Red Delicious and Fuji fruit. Overall, AVG seemed to have a stronger effect on the measured ripening traits, and its combination with heat treatment improved fruit quality of cold-stored Lodi apples and reduced ethylene production the most for all but Lodi.

Determination of the lattice translation across {110} APBs in GaAs

1988 ◽  
Vol 46 ◽  
pp. 600-601
Author(s):  
D.R. Rasmussen ◽  
N.-H. Cho ◽  
C.B. Carter
Keyword(s):  
Grain Boundaries ◽  
Lower Energy ◽  
Antiphase Boundary ◽  
The Other ◽  
Boundary Structure ◽  
Interface Plane ◽  
Inversion Symmetry ◽  
High Angle ◽  
Equilibrium Distance

Domains in GaAs can exist which are related to one another by the inversion symmetry, i.e., the sites of gallium and arsenic in one domain are interchanged in the other domain. The boundary between these two different domains is known as an antiphase boundary [1], In the terminology used to describe grain boundaries, the grains on either side of this boundary can be regarded as being Σ=1-related. For the {110} interface plane, in particular, there are equal numbers of GaGa and As-As anti-site bonds across the interface. The equilibrium distance between two atoms of the same kind crossing the boundary is expected to be different from the length of normal GaAs bonds in the bulk. Therefore, the relative position of each grain on either side of an APB may be translated such that the boundary can have a lower energy situation. This translation does not affect the perfect Σ=1 coincidence site relationship. Such a lattice translation is expected for all high-angle grain boundaries as a way of relaxation of the boundary structure.

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