Internal Ethylene Concentration Research Articles

Development of 1-aminocyclopropane-1-carboxylic Acid Synthase and Polygalacturonase Activities During the Maturation and Ripening of Tomato Fruit

Abstract The changes in ethylene production rates and development of 1-aminocyclopropane-l-carboxylic acid (ACC) synthase and polygalacturonase (PG) activities were studied during the maturation and ripening of tomato fruit (Lycopersicon esculentum Mill, cv. ‘Castlemart’). There was a linear relationship between internal ethylene concentration and ethylene production rate; both increased exponentially as tomato fruit reached more advanced maturity and ripening. Thus, both of them correlate with the maturity and the ripening stages of tomatoes. A small increase in ACC synthase activity was observed at the early mature green stages which was followed by a marked increase at the breaker stage. ACC level followed the same pattern as ACC synthase activity. PG activity was undetectable or low throughout the mature green stages, but increased significantly after reaching the breaker stage. These data indicate that the onset of the development of ACC synthase activity precedes that of PG activity.

Influence of Storage Atmospheres and Procedures on 1-Aminocyclopropane-1-Carboxylic Acid Concentration in Relation to Flesh Firmness in ‘Golden Delicious’ Apple

Abstract Firmness loss, increase in 1-aminocyclopropane-l-carboxylic acid (ACC) concentrations, and increase in internal ethylene concentrations were greatest in airstored fruit of ‘Golden Delicious’ apple (Malus domestica Borkh.) and lowest in controlled-atmosphere (CA)-stored fruit receiving a “rapid CA” or a “prestorage high carbon dioxide” storage procedure. Changes in apples kept in “slow CA” were intermediate. The accumulation of ACC in fruit was related closely to the subsequent flesh softening and increase in internal C2H4 concentration, and these processes were suppressed to different degrees in CA-stored fruit, depending on the storage procedures.

Comparison of methods for estimating the onset of the respiration climacteric in unpicked apples

SummaryThe rate of deterioration of apples in storage is influenced by their maturity at harvest. Three methods based on the occurrence of the rise in ethylene production which is coincident with the climateric rise in respiration, have been used to assess the maturity of the crop for various apple cultivars.In the first method internal ethylene concentrations (IEC) were measured in fruit samples soon after picking at weekly intervals. The onset of the climacteric was defined as the date when the internal concentration passed 0.1 μ l-1. The other two methods were based on ethylene production by bulk samples picked at weekly intervals. In one, the mean delay between picking and the rise in ethylene production (DEP) was calculated, and the other recorded the first date on which at least half the replicate samples showed immediate ethylene production (IEP).The dates determined by IEC and IEP were generally in agreement for each cultivar but there was little evidence of correlation in respect to site and seas...

Initiation of Rapid Ethylene Synthesis by Apple and Pear Fruits in Relation to Storage Temperature

The influence of storage temperature on the onset of rapid ethylene production was investigated for fruits of Conference pear (Pyrus communis L.) and five cultivars of apple (Malus domestica Borkh.). The time taken from harvest to rapid ethylene production was shorter and more uniform at 3 °C than at 18–20 °C for Conference pears and Golden Delicious apples. Increases in internal ethylene concentration, 1-amino cyclopropane-1-carboxylic acid concentration and ethylene production were simultaneous in Golden Delicious apples at 3 °C. When Golden Delicious apples were held at 3 °C for 48 h and then kept at 20 °C the mean time of onset of ethylene production was similar to that for apples held continuously at 20 °C. However, two periods of 48 h at 3 °C caused earlier ethylene production. Conversely, ethylene production at 3 °C was delayed by transfer to 20 °C for two periods of 48 h. Cox's Orange Pippin and other apple cultivars tended to show more synchronous ethylene production at 3 °C than at higher temperatures but the mean time of onset was either unaffected by temperature or slighdy delayed at lower temperature. Acceleration of the onset of ethylene production by low temperature was never observed in Cox's Orange Pippin apples harvested at weekly intervals from 10 August to 17 September.

RELATIONSHIP BETWEEN ETHYLENE PRODUCTION AND TASTE PANEL PREFERENCE OF STARKRIMSON RED DELICIOUS APPLES

Untrained taste panels rated freshly harvested Starkrimson Red Delicious apples that had evolved enough ethylene after 1 h to raise the concentration in a 500-mL container to 0.15–4.5 ppm higher in overall eating quality than fruit producing more, or less ethylene. These rates of accumulation correspond to production of between 0.35 and 10.5 nL∙g−1∙h−1 ethylene, and internal ethylene concentrations of from 1.3 to 51 ppm.Key words: Malus domestica, maturity indices, Starkrimson Red Delicious, climacteric, taste panel

Temperature Effects on Uptake and Effectiveness of Glyoxal Dioxime in ‘Hamlin’ Oranges1

Abstract Temperature effects on glyoxal dioxime (Pik-Off) stimulation of ethylene production and fruit loosening and on uptake of 14C-glyoxal dioxime were investigated using ‘Hamlin’ oranges [Citrus sinensis (L.) Osb.] harvested with petioles attached. Oranges treated with 250 ppm glyoxal dioxime produced significantly more ethylene than untreated fruit at 20, 25, and 30°C but not at 10 or 15°. Fruit loosening was correlated with internal ethylene concentration, producing a significant loosening effect for glyoxal dioxime at 20, 25, and 30°. Lack of effectiveness of glyoxal dioxime for inducing fruit loosening at low temperatures (10 and 15°) cannot be explained by a reduced rate of uptake but may result from impairment of ethylene biogenesis by fruit tissue.

Internal Ethylene Concentrations of ‘McIntosh’ Apples After Harvest1

Abstract In a low ethylene environment (< 1 ppm) at 19°C, the rate of ethylene evolution was positively related to the concentration of ethylene in the cores of ‘McIntosh’ apples (Malus domestica, Borkh.). Maximum retention of flesh firmness at 1° was associated with fruit internal ethylene concentrations below I ppm, which were obtained by ethylene removal from the storage atmosphere in combination with 3 treatments to suppress ethylene biosynthesis: orchard-applied daminozide, early harvest, and low O2 tension in storage.

Extraction of Endogenous Ethylene and Ethane from Leaves ofPhaseolus vulgarisL.

A procedure to recover small volumes of gases from plant tissues by vacuum extraction is described. Changes in the volume of the gases and the concentrations of ethylene and ethane recovered from Phaseolus leaves were observed when the evacuation conditions during extraction were altered. These changes were different in the primary leaves and in the second trifoliate leaves. Thus, estimates of internal ethylene and ethane concentrations appear to be influenced both by the morphology of the tissue and the evacuation conditions employed. There was a positive correlation between the concentrations of ethylene and ethane in the gaseous extracts. The internal ethylene concentrations in the primary, first trifoliate, and second trifoliate leaves, considered together, were correlated with their respective rates of ethylene emanation.

果実•野菜の成熟生理と貯蔵に関する研究 (第2報)

The changes in respiration rates, ethylene production, internal ethylene concen trations and flesh firmness were investigated during the maturation and ripening periods of pear fruits, using 3 species and several cultivars, as follows: Pyrus communis L. var. sativa DC. (Bartlett, La France and Winter Nelis), Pyrus serotina Rehd. var. culta (Yakumo, Nijisseiki, Niitaka and Kikusui), Pyrus ussuriensis Maxim. var. sinesis Kikuchi (Ya-li, Rai-Yan-Tsu-li and Auto-li). The fruits were picked 2-3 times at different stages of maturity and stored at 20°C.1. Three cultivars of P.communis, Bartlett, La France, and Winter Nelis showed a typical climacteric pattern of respiration. Respiration and ethylene production in both La France and Winter Nelis were much lower than in Bartlett.2. Among P.serotina, Yakumo and Kikusui fruits picked at two different stages of maturity showed a rise in respiration; respiration didn′t rise in Nijisseiki and Niitaka fruits picked at commercial harvest maturity, but did in fruits picked at the immature stage. Ethylene production in Yakumo increased with rising respiration, but the other 3 cultivars maintained a very low level of production during the experimental period.In Nijisseiki, exogenous ethylene treatment caused a rise in respiration immedi ately after picking. This effect continued only in the presence of exogenous ethylene, and could be reproduced in the same fruit when re-treated with ethylene after a month of storage.It was concluded that Yakumo and Kikusui can be classified as climacteric fruits, while Nijisseiki and Niitaka are non-climacteric fruits.3. Three cultivars of P.ussuriensis; Ya-li, Rai-Yan-Tsu-li and Auto-li showed a typical climacteric accompanying a rise in ethylene production.

Control of Lateral Bud Growth inPhaseolus vulgarisL. by Ethylene in the Apical Shoot

Elongation growth of the first trifoliate leaf axillary bud was induced by physical restriction of the apical growth or by treating the apical shoot with ethylene or ethephon. There is evidence to suggest that the promotion of axillary bud development by ethylene action on the apical shoot was associated with the availability of freely diffusible ethylene in the tissues of the treated shoot. Loss of apical dominance was not, apparently, directly dependent on either the internal ethylene concentration (i.e. concentration in the vacuum-extracted gases) or on the rate of ethylene emanation. The effects of aminoethoxyvinyl glycine (AVG) and silver nitrate on ethylene production were examined. Although treatment of the shoot with tri-iodobenzoic acid (TIBA) induced various morphological responses in the plant, including axillary bud outgrowth, which appeared similar to the responses to ethylene, the initial effect of TIBA is not thought to be ethylene-mediated.

Effects of Aminoethoxyvinylglycine on Internal Ethylene Concentrations and Storage of Apples1

Abstract Preharvest sprays of aminoethoxyvinylglycine (AVG) drastically suppressed internal ethylene concentrations, and delayed or prevented ripening of ‘McIntosh’, ‘Spartan’, and ‘Spencer’ apples (Malus domestica Borkh.) at room temperature (ca. 25°C) after harvest, the magnitude of delay varying with cultivar and with AVG concentration. However, after treated fruit had been stored with untreated fruit at 0°C, little or no difference in ripeness was discernible between treated and untreated samples. Internal ethylene concentrations in treated fruit after storage were much less than in controls but generally exceeded 1 ppm. Infiltration of ripe fruit with AVG severely suppressed ethylene production, but 2 minute dips in AVG solutions had no effect until after prolonged time in storage.

果実•野菜の成熟生理と貯蔵に関する研究 (第1報)

Physiological changes associated with the maturation of apples on the tree were investigated using three apple cultivars: Jonathan (medium maturing, short shelf life), Indo (late, intermediate shelf life), and Ralls Janet (late, long shelf life). Fruits were picked 5-13 times at weekly intervals during the maturing period, and changes in respiration (CO2 evolution), ethylene emanation, and internal ethylene concentrations were determined in relation to several criteria of maturation, such as fruit weight, titratable acidity, content of soluble solids, starch, water soluble pectin, total pectin, and firmness of flesh. The changes in amylase and pectin methyl esterase activities were also determined.1. While a climacteric rise in respiration was clearly observed during maturation on the tree in Jonathan and Indo apples, it did not occurr in Ralls Janet apples until the normal harvest period. Ralls Janet apples, however, showed a typical climacteric rise both when they were stored at 20°C, or attached to the tree, far beyond the usual harvesting time until the time when most fruits had naturally dropped.2. Internal ethylene concentration was found to increase two weeks before the climacteric onset of respiration, reaching a levels of 4ppm at the climacteric minimum in Jonathan apples. In Indo and Rails Janet apples, a range of 0.3-0.5ppm predominated from a month before the climacteric onset. A sharp increase was found almost simultaneously with the climacteric rise in Indo; in Ralls Janet, the increase occurred at the time of climacteric minimum, reaching levels of several ppm.3. Rapid increases in ethylene emanation occurred almost simultaneously with the climacteric rise in Jonathan and Indo, but only a slight increase was observed in Rails Janet even after the increase in respiration and internal ethylene concentration.4. The relationship between maturity and the change in respiration was also compared among the three. With Jonathan, maturation advanced rapidly and the fruit became edible at the climacteric minimum of respiration. Indo apples became edible after the rise of respiration; the fruits contained high levels of starch and total pectin, and their decomposition progressed slowly. With Ralls Janet, while maturation advanced slowly, the rise of respiration occurred very late, and the climacteric peak was found a month after the fruits were edible.5. Respiration rates and internal ethylene concentrations in Ralls Janet apples were much lowr than those of Jonathan and Indo apples through the pre-and post- climacteric phases. This fact seems to be related to the fact that Ralls Janet apples have a longer shelf life in comparison with the other two cultivars.

The Relationship Between Endogenous Ethylene and Abscission of Mature Apple Fruits1

Abstract The changes in ethylene concentration of attached, horticulturally mature ‘Lodi’, ‘McIntosh’ and ‘Golden Delicious’ apples (Malus domestica Borkh.) were estimated by measuring the ethylene present in a tube sealed over the fruit calyx. Measurements of this gas sample [the equilibrium ethylene concentration (EEC)] were directly proportional to the internal ethylene concentration (IEC) of the fruit. In ‘Lodi’ and ‘McIntosh’, an increase in the EEC preceded abscisision by at least 3 days. The length of time to abscission after increases in EEC were noted was negatively correlated with daily mean temperature in ‘McIntosh’. ‘Golden Delicious’ fruits did not show a relationship between the EEC and abscission. The commercial harvest period of ‘Lodi’ preceded the rise in EEC. In ‘McIntosh’, ethylene accumulation occurred both during and after the commercial harvest.

Fruit Growth and Development, Ripening, and the Role of Ethylene in the ‘Honey Dew’ Muskmelon1

Abstract The muskmelon cultivar Honey Dew (Cucumis melo L.) has unique horticultural and physiological characteristics, most notably an unusually long period between attainment of acceptable horticultural maturity and self-ripening in the field. Patterns of flowering, fruit set, fruit growth, solids accumulation, softening, ethylene production, respiration, and variation among individual fruits were studied during several seasons. Internal ethylene concentration may be estimated by the following formula: ppm internal = 3.7 ± 1.2 × rate of production in µl/kg-hr. The act of harvesting had no effect on ethylene production or internal concentration. Full ripening required an internal ethylene concentration of about 3 ppm. Horticultural maturity was attained at 35 to 37 days after anthesis, but self-ripening required about 47 days. Commercial harvests include fruits in this range of ages, so treatment with ethylene is required for uniform ripening and consumer satisfaction.

Stress Ethylene Production in Apple Shoots1

Abstract Increases in internal ethylene concentrations occurred after attached and detached apple (Malus domestica, Borkh. cv. Winesap) shoots were placed in a horizontal position. Ethylene was higher in the underside of the shoot, and decreased linearly in a basipetal direction along the axis. Bent and horizontally-oriented detached shoots did not increase in ethylene at 20°C, but increased to identical levels at 30°, suggesting that responses to the 2 types of stress were identical. Although gravitational stress alone increased ethylene levels, an experiment designed to separate bending stress from gravitational stress was inconclusive because rotation decreased shoot ethylene levels.

Comparison of Propylene-induced Responses of Immature Fruit of Normal and rin Mutant Tomatoes

Continuous application of propylene to 40 to 80% mature fruits of normal tomato strains (Lycopersicon esculentum Mill.) advanced ripening in fruits of all ages by at least 50%. Although preclimacteric respiration was stimulated by propylene treatment, there was no concomitant increase in ethylene production. Once ripening commenced, the rates of endogenous ethylene production were similar in both propylene-treated and untreated fruits. Continuous exposure to propylene also stimulated respiration in immature fruits of rin, a nonripening mutant. Although respiration reached rates similar to those during the climacteric of comparable normal fruits there was no change in endogenous ethylene production which remained at a low level. Internal ethylene concentrations in attached 45 to 75% mature fruits of rin and a normal strain were similar. It is suggested that the onset of ripening in normal tomato fruit is not controlled by endogenous ethylene, although increased ethylene production is probably an integral part of the ripening processes.

EFFECT OF WATER STRESS UPON ENDOGENOUS ETHYLENE LEVELS IN VICIA FABA

SummaryConditions of drought or waterlogging lead to greatly increased internal ethylene concentrations in Vida faba L. These increases appear to be due partly to decreased diffusion and partly to increased synthesis and are superimposed on normal diurnal fluctuations in internal ethylene concentration. The higher concentrations observed are correlated with a reduction in growth rate and increased leaf and flower abscission and senescence. The role of ethylene in the mediation of developmental responses to water stress is discussed.

Internal Ethylene Concentrations in Apple Fruits Attached to or Detached from the Tree1

Abstract A method is described for the measurement of internal ethylene concentration in fruits on the tree. Ethylene levels in ‘Red Delicious’ fruits immediately after harvest were similar to those in fruits on the tree during development and ripening. The levels varied mostly between 0.02 to 0.15 ppm during the period from 83 to 140 days from bloom and sharply increased from 10 to 1000-fold within 5 days as autocatalytic ethylene production began. Ripening followed the upsurge in ethylene production. Isolating fruit from leaves by girdling plus defoliation of spur leaves hastened the increase in internal ethylene by approximately 1 month. Girdling or defoliating the spur did not markedly alter the onset of autocatalytic ethylene production compared to that observed by fruits on normal spurs. The data support the concept that fruits receive a ripening inhibitor from the leaves.

Physiology of Oil Seeds

To further elucidate the regulation of dormancy release, we followed the natural afterripening of Virginia-type peanut (Arachis hypogaea L.) seeds from about the 5th to 40th week after harvest. Seeds were kept at low temperature (3 +/- 2 C) until just prior to testing for germination, ethylene production, and internal ethylene concentration. Germination tended to fluctuate but did not increase significantly during the first 30 weeks; internal ethylene concentrations and ethylene production remained comparatively low during this time. When the seeds were placed at room temperature during the 30th to 40th weeks after harvest, there was a large increase in germination, 49% and 47% for apical and basal seeds, respectively. The data confirm our previous suggestion that production rates of 2.0 to 3.0 nanoliters per gram fresh weight per hour are necessary to provide internal ethylene concentrations at activation levels which cause a substantial increase of germination. Activation levels internally must be more than 0.4 microliter per liter and 0.9 microliter per liter for some apical and basal seeds, respectively, since dormant-imbibed seeds containing these concentrations did not germinate. Abscisic acid inhibited germination and ethylene production of afterripened seeds. Kinetin reversed the effects of ABA and this was correlated with its ability to stimulate ethylene production by the seeds. Ethylene also reversed the effects of abscisic acid. Carbon dioxide did not compete with ethylene action in this system. The data indicate that ethylene and an inhibitor, possibly abscisic acid, interact to control dormant peanut seed germination. The inability of CO(2) to inhibit competitively the action of ethylene on dormancy release, as it does other ethylene effects, suggests that the primary site of action of ethylene in peanut seeds is different from the site for other plant responses to ethylene.

Mode of Action of Ascorbic Acid in Inducing Selective Abscission of Citrus Fruit, Citrus sinensis, Osbeck1

Abstract Ascorbic acid (AA) application at relatively high concentration, 1-5% w/v, accelerated abscission of fruit more than of leaves and increased the ethylene production of both organs by about 10 fold. This selective abscission may be related to the following factors: a) the internal ethylene concentration rises in treated fruit up to levels above 1 ppm whereas its concentration in treated leaves is estimated to be lower; b) leaves incorporate less ascorbic acid than fruit; c) A A induces a marked injury to the fruit’s rind and little to no visible injury to leaves. Ascorbic acid treatment increased the sensitivity of both leaves and fruit to external ethylene and increased the respiratory activity of both. This rise in fruit respiration might be related to the increase in internal ethylene and injury.