Abscission and dehiscence in the squirting cucumber, Ecballium elaterium. Regulation by ethylene

When treated with ethylene, mature fruits of the squirting cucumber (Ecballium elaterium (L.) A. Rich) abscind and dehisce prematurely. Abscission of male flowers is also accelerated by ethylene. Visible signs of senescence, a rise in ethylene production, and reduced carbon dioxide production always precede abscission or dehiscence in untreated fruits and flowers. The amounts of diffusible cellulase increase in tissues on both sides of the fruit abscission zone after exposure to ethylene. Anatomical features of this abscission zone are described.The leaves of Ecballium do not abscind although the blade and petiole produce large amounts of ethylene at senescence, nor do they separate when ethylene is supplied. Ethylene treatment of attached fruit peduncles accelerates their rate of elongation in the growing zone below the apical hook. The regulation of growth and abscission in these organs is discussed.

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Climacteric Fruit Produce a Diminished Respiratory Climacteric When Ripened on the Plant

HortScience ◽

10.21273/hortsci.31.4.690e ◽

1996 ◽

Vol 31 (4) ◽

pp. 690e-691

Author(s):

M.E. Saltveit

Keyword(s):

Carbon Dioxide ◽

Oxygen Consumption ◽

Organic Acids ◽

Ethylene Production ◽

Carbon Dioxide Production ◽

Plant Tissues ◽

Rapid Rise ◽

Fruit Crops ◽

Climacteric Fruit

Respiration (i.e., carbon dioxide production and oxygen consumption) increases as ripening is initiated in a group of harvested fruit called climacteric. This group includes many horticulturally important fruit crops, such as apples, avocados, bananas, melons, peaches, pears, and tomatoes. Other fruit, which includes cherries, citrus, and strawberries, do not exhibit an increase in respiration as they ripen and are called nonclimacteric. Measurements of carbon dioxide production by ripening apples, melons, and tomatoes revealed a well-defined climacteric, but only in harvested fruit. The respiratory climacteric was greatly diminished or absent from these fruit when they ripened while attached to the plant. Fixation of respired carbon dioxide through photosynthesis or into organic acids was insufficient to account for the diminished amount of carbon dioxide evolved from ripening attached climacteric fruit. Unlike the respiratory climacteric, an increase in ethylene production occurred in both attached and harvested climacteric fruit. Ethylene stimulates respiration in most plant tissues. The rapid rise in respiration as soon as attached ripening climacteric fruit were harvested or abscised suggests that an inhibitor of ethylene-stimulated respiration may be translocated from the plant and prevent the climacteric rise in respiration in attached ripening fruit.

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Interaction of Water Loss and Fruit Ripening Promote Postharvest Cluster Tomato Fruit Abscission

HortScience ◽

10.21273/hortsci.41.4.979a ◽

2006 ◽

Vol 41 (4) ◽

pp. 979A-979

Author(s):

Jeffrey K. Brecht ◽

Kimberly M. Cordasco

Keyword(s):

Relative Humidity ◽

Fruit Ripening ◽

Water Loss ◽

Ethylene Production ◽

Tomato Fruit ◽

Abscission Zone ◽

Retail Environment ◽

Fruit Abscission ◽

Zone Development ◽

Exogenous Ethylene

Abscission of cluster tomatoes commonly limits product marketability in the retail environment. Ripening and exogenous ethylene exposure are assumed to play important roles in cluster tomato fruit abscission. `Clarance' and `DRW7229' fruit harvested at either mature green or partially ripened stages did not abscise during storage for 2 weeks at 20 °C and 95% to 100% relative humidity (RH), although respiration and ethylene production indicated that all fruit reached the postclimacteric stage. Exogenous ethylene (1 or 10 ppm) exposure for 8 days at 20 °C and 95% to 100% RH also did not induce fruit abscission for either cultivar, although pedicel and sepal yellowing were observed. Fruit from clusters stored at 20 °C and 20% or 50% RH abscised if sepal shrivel became noticeable before the fruit reached the full red ripeness stage, while no abscission occurred in fruit that reached the full red stage prior to the appearance of sepal shrivel; no fruit stored in 95% to 100% RH abscised. Fruit that ripened prior to the appearance of sepal shrivel were “plugged” (i.e., tissue underlying the stem scar was pulled out) if manual fruit detachment from the pedicel was attempted. These results indicate that there is an interaction of water loss and fruit ripening in promoting abscission zone development in cluster tomatoes.

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Physiological Factors Affecting Response of Mature `Valencia' Orange Fruit to CMN-Pyrazole. II. Endogenous Concentrations of Indole-3-Acetic Acid, Abscisic Acid, and Ethylene

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.126.4.420 ◽

2001 ◽

Vol 126 (4) ◽

pp. 420-426 ◽

Cited By ~ 13

Author(s):

Rongcai Yuan ◽

Ulrich Hartmond ◽

Walter J. Kender

Keyword(s):

Acetic Acid ◽

Abscisic Acid ◽

Ethylene Production ◽

Abscission Zone ◽

Endogenous Iaa ◽

Fruit Abscission ◽

Valencia Orange ◽

Orange Fruit ◽

Indole 3 Acetic Acid ◽

Observation Period

Endogenous concentrations of IAA and ABA in the peel, pulp, seed, and abscission zone of mature `Valencia' oranges [Citrus sinesis (L.) Osbeck] were determined by high-performance liquid chromatography and enzyme-linked immunosorbent assay from early November 1998 to mid-June 1999. Ethylene production of mature `Valencia' oranges during the same period was determined by gas chromatography. IAA concentrations in the pulp and seed were three to five times lower than those in the peel over the 7-month observation period. IAA concentration in the abscission zone and peel was high from late April to mid-May, the period of less responsiveness to abscission chemicals. ABA concentration in the pulp was low over the entire observation period. ABA concentration in the abscission zone and peel was low during the less responsive period. Ethylene production was always low except for a slight increase during late December and early February. The IAA to ABA ratio was high in the fruit abscission zone during the less responsive period. Fruit detachment force of CMN-pyrazole-treated fruit was positively correlated with the ratio of endogenous IAA to ABA or endogenous IAA, but negatively to endogenous ABA in the fruit abscission zone. These data suggest the balance between IAA and ABA in the fruit abscission zone may be an important factor in determining sensitivity and thereby the response of mature `Valencia' orange fruit to abscission chemicals. Chemical names used: abscisic acid (ABA); indole-3-acetic acid (IAA); 5-chloro-3-methyl-4-nitro-1H-pyrazole (CMN-pyrazole).

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Enhancing Ripening Characteristics of “Netted” and `Honeydew”-type Melons

HortScience ◽

10.21273/hortsci.30.4.766c ◽

1995 ◽

Vol 30 (4) ◽

pp. 766C-766

Author(s):

Krista C. Shellie ◽

David Wolf

Keyword(s):

Carbon Dioxide ◽

Genetic Control ◽

Ethylene Production ◽

Cucumis Melo ◽

Gene Action ◽

Dominant Gene ◽

Central Cavity ◽

Gas Sampling ◽

Fruit Abscission ◽

Postharvest Life

“Netted” (Cucumis melo var. reticulatus Naud.) cantaloupes typically abscise when mature, and have a shorter postharvest life than “Honeydew” (Cucumis melo var. inodoris Naud.) -type melons. The amount of ethylene and carbon dioxide produced by two cantaloupe genotypes (slipping), one Honeydew genotype (non-slipping), and the F1 hybrids derived from the slipping x non-slipping genotypes were measured during ripening to understand the genetic control of ethylene and fruit abscission. Sterile, nondestructive gas sampling ports inserted into 20-day-old fruit were used to extract samples from the central cavity of the melons and monitor ethylene and carbon dioxide from day 30 until the fruit was horticulturally mature. Honeydew melons had a lower rate of respiration during maturation and ripening than Netted melons, and Netted melons produced 10-fold more ethylene during ripening than Honeydew types. F1 fruit produced ethylene at levels similar to the Netted parent, abscissed 2 to 4 days later than the Netted parent, yet respired during maturation and ripening like the Honeydew-type parent. Ethylene production, respiration, and abscission appear to be controlled by dominant gene action.

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ETHYLENE METABOLISM IN TOMATO FRUIT: III. EFFECT OF 2,4-DINITROPHENOL ON RESPIRATION, ETHYLENE EVOLUTION, AND RIPENING

Canadian Journal of Biochemistry and Physiology ◽

10.1139/y59-007 ◽

1959 ◽

Vol 37 (1) ◽

pp. 53-59 ◽

Cited By ~ 1

Author(s):

Mary S. Spencer

Keyword(s):

Carbon Dioxide ◽

Oxidative Phosphorylation ◽

Fruit Ripening ◽

Ethylene Production ◽

Cell Walls ◽

Tomato Fruit ◽

Carbon Dioxide Production ◽

Carbon Dioxide Evolution ◽

Ethylene Evolution

The role of phosphorylation in fruit ripening was investigated by the introduction of a phosphorylation uncoupling agent, 2,4-dinitrophenol (DNP), into intact fruit. DNP produced a large increase in carbon dioxide evolution by mature green tomatoes, but not by tomatoes in earlier or later stages of maturity. In contrast to its effect on carbon dioxide production, DNP treatment of mature green tomatoes resulted in an immediate depression of ethylene evolution and in failure of the fruit to ripen normally. This suggests a requirement for oxidative phosphorylation for fruit ripening and ethylene production. It was also observed that cell walls of mature green tomatoes treated with the uncoupling agent became wavy and greatly thickened.

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Ethylene and Carbon Dioxide Production in Detached Fruit of Selected Pepper Cultivars

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.124.4.402 ◽

1999 ◽

Vol 124 (4) ◽

pp. 402-406 ◽

Cited By ~ 26

Author(s):

Lucia Villavicencio ◽

Sylvia M. Blankenship ◽

Douglas C. Sanders ◽

William H. Swallow

Keyword(s):

Carbon Dioxide ◽

Ethylene Production ◽

Carbon Dioxide Production ◽

King Arthur ◽

Ethylene Evolution ◽

Green Fruit ◽

Respiration Rates ◽

Maturity Stages ◽

Hot Peppers ◽

Bell Peppers

Bell peppers (Capsicum annuum L.) are classified as nonclimacteric fruits while some hot peppers have been reported as climacteric. Responses of peppers to exogenously applied ethylene-releasing compounds suggest ethylene involvement in the ripening process. Ethylene production and respiration rates in 13 cultivars of pepper: `Camelot', `Cherry Bomb', `Chiltepin', `Cubanelle', `Banana Supreme', `Habanero', `Hungarian Wax', `Mesilla', `Mitla', `Savory', `Sure Fire', `Tabasco', and `King Arthur' were studied under greenhouse and field conditions. Fruit from each cultivar were harvested at different maturity stages determined by color, ranging from mature-green to full red-ripe. Carbon dioxide and ethylene production were measured by gas chromatography. Both variables were significantly different among maturity stages for all cultivars. Respiration rates were between 16.5 and 440.3 mg·kg-1·h-1 CO2. Ethylene production ranged from 0.002 to 1.1 μL·kg-1·h-1. Two patterns of CO2 production were identified: higher CO2 production for mature-green fruit with successive decreases for the rest of the maturity stages or lower respiration rates for mature-green fruit with an increase in CO2 production either when fruit were changing color or once fruit were almost totally red. A rise in CO2 production was present for most cultivars. Ethylene evolution increased significantly at maturity or before maturity in all cultivars except `Cubanelle' and `Hungarian Wax'. Respiration rates and ethylene production were significantly different among cultivars at the mature-green and red stages.

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The Effect of MethyI Jasmonate on Ethylene Production, ACC Oxidase Activity and Carbon Dioxide Evolution in the Yellowish-Tangerine Tomato Fruits (Lycopersicon esculentum Mill.)

Acta Agrobotanica ◽

10.5586/aa.1996.006 ◽

2013 ◽

Vol 49 (1-2) ◽

pp. 67-72

Author(s):

Janusz Czapski ◽

Artur Miszczak ◽

Marian Saniewski

Keyword(s):

Carbon Dioxide ◽

Ethylene Production ◽

Oxidase Activity ◽

Green Light ◽

Acc Oxidase ◽

Carbon Dioxide Production ◽

Carbon Dioxide Evolution ◽

Light Yellow ◽

Endogenous Ethylene ◽

Advanced Stages

The yellowish-tangerine tomato (cv. Bursztyn) in the green, light yellow and yellow stages of ripening were treated with 0.1% and 1.0% of methyl jasmonate (JA-Me) in lanolin paste and kept for several days and then they were evaluated for production of ethylene, ACC oxidase activity and CO<sub>2</sub> evolution. Production of endogenous ethylene in mature green fruits was low and increased during ripening. JA-Me stimulated ethylene production and ACC oxidase activity in all investigated stages of fruit ripening. Slices excised from mature green fruits produced highest amount of carbon dioxide as compared to more advanced stages of ripening. JA-Me in O,1 % and 1,0% concentrations increased significantly CO<sub>2</sub> evolution in green fruits, while in light yellow and yellow fruits only higher concentration of JA-Me stimulated carbon dioxide production.

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Cellulase Activity and Gene Expression in Citrus Fruit Abscission Zones during and after Ethylene Treatment

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.123.5.781 ◽

1998 ◽

Vol 123 (5) ◽

pp. 781-786 ◽

Cited By ~ 14

Author(s):

William C. Kazokas ◽

Jacqueline K. Burns

Keyword(s):

Gene Expression ◽

Cellulase Activity ◽

Storage Period ◽

Abscission Zone ◽

Cellulase Gene ◽

Immature Fruit ◽

Ethylene Treatment ◽

Fruit Abscission ◽

Valencia Orange ◽

Low Levels

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.

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