scholarly journals Heat-shock-induced Chilling Tolerance in Malvaceous Seedlings

HortScience ◽  
1996 ◽  
Vol 31 (4) ◽  
pp. 601b-601
Author(s):  
M.E. Mangrich ◽  
M.E. Saltveit
Keyword(s):  
Heat Shock ◽  
Chilling Injury ◽  
Chilling Tolerance ◽  
Heat Treatments ◽  
Sensitive Species ◽  
Immersion Method ◽  
Heated Water ◽  
Chilling Sensitivity ◽  
Heat Shocks ◽  
The Tropics

Crops indigenous to the tropics and subtropics and some temperate crops suffer physiological injury when exposed to temperatures <12°C. Heat shock has induced chilling tolerance in a number of sensitive species (e.g., corn, cucumber, and tomato), but not in okra. To study this anomaly, we investigated the chilling sensitivity and heat shock response of a variety of Malvaceous species (i.e., cotton, hibiscus, kenaf, and okra). Seedlings with 8- to 12-mm long radicles were exposed to heat shock temperatures of 40 to 45°C for 2 to 12 minutes. Heat shocks were applied by two methods, floating the seeds in petri dishes on heated water and immersing the seeds in the heated water. The seedlings were held at 20°C for 2 hours after the heat treatments and then chilled at 2.5°C for 3 days. After chilling, seedlings were placed at 25°C for 3 additional days. The growth at 25°C was used as an assessment of chilling injury. Although there was a great deal of variability among the seedlings, a significant number of the okra and kenaf seedlings were more tolerant to chilling after heat shock: (i.e., more growth subsequent to chilling) compared to nonheat-shocked controls. More chilling tolerance was induced by the floating method than the immersion method. The response of cotton seedlings to heat-shock was variable, and the seedlings appeared damaged by even slight heat treatments (i.e., 4 minutes at 40°C). The variability in the capacity of heat-shocks to induce chilling tolerance in seedlings of Malvaceous species will be discussed.

scholarly journals Sensitivity of Seedling Radicles to Chilling and Heat-shock-induced Chilling Tolerance

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 848C-848
Author(s):  
Abdur Rab ◽  
Mikal E. Saltveit
Keyword(s):  
Heat Shock ◽  
Mung Bean ◽  
Lateral Roots ◽  
Chilling Injury ◽  
Chilling Tolerance ◽  
Shock Temperature ◽  
Chilling Sensitivity ◽  
Hibiscus Esculentus ◽  
Time Required ◽  
Shock Proteins

Chilling sensitivity increased as the radicle of germinating corn (Zea mays L. `Jubilee' hybrid), cucumber (Cucumis sativus L. `Poinsett 76'), mung bean (Phaseolus aureus Roxb. `Berkin'), and tomato (Lycopersicon esculentum Mill. `Rio Grande') seeds increased in length from 1 to 7 mm. In contrast, radicles of germinating okra (Hibiscus esculentus L. `Clemson' spineless) seeds exhibited similar levels of chilling sensitivity at all radicle lengths. The degree of chilling sensitivity varied among the species in relation to time required to elicit a significant response and the magnitude of the elicited response. Based on subsequent radicle elongation, okra and cucumber were the most sensitive species to chilling at 2.5C for 96 h; tomato and corn were relatively less sensitive, and mung bean was the least sensitive. This pattern of sensitivities changed when other criteria were used to evaluate chilling sensitivity. The development of lateral roots decreased with prolonged chilling in all species, except for corn in which the apical tip remained viable even after 192 h of chilling. Heat shock (0 to 10 min at 45C) induced chilling tolerance in all species, except okra. In okra, neither increasing the heat shock temperature nor decreasing the severity of chilling (i.e., temperature and duration of exposure) resulted in a significant reduction in chilling injury. The differential induction of heat shock proteins in okra and the other species is discussed.

scholarly journals Sensitivity of Seedling Radicles to Chilling and Heat-shock-induced Chilling Tolerance

1996 ◽  
Vol 121 (4) ◽  
pp. 711-715 ◽  
Author(s):  
Abdur Rab ◽  
Mikal E. Saltveit
Keyword(s):  
Heat Shock ◽  
Mung Bean ◽  
Lateral Roots ◽  
Chilling Injury ◽  
Chilling Tolerance ◽  
Significant Response ◽  
Tomato Seedling ◽  
Shock Temperature ◽  
Chilling Sensitivity ◽  
Time Required

The sensitivity of corn, cucumber, mung bean, and tomato seedling radicles to chilling (i.e., inhibition of subsequent elongation at 25 C after chilling at 2.5 C) was greater for radicles 5 to 7 mm long than for radicles 1 mm long. In contrast, radicles of germinating okra seeds had a similar level of chilling inhibition (i.e., 70% to 90%) at lengths of 1 to 7 mm. For seeds with 1-mm-long radicles, subsequent radicle elongation for cucumber was inhibited only 2% by 72 hours of chilling at 2.5 C, while it was inhibited about 20% for corn, mung bean, and tomato. For seeds with 5- to 7-mm-long radicles, chilling inhibition was 50% to 70% for corn, mung bean, and tomato and 80% to 90% for cucumber and okra. The degree of chilling sensitivity varied among species in relation to time required to elicit a significant response and the magnitude of the elicited response. The development of lateral roots decreased with prolonged chilling in all species. Heat shock (i.e., 4 to 10 minutes at 45 C) induced chilling tolerance in all species except okra. In okra, neither increasing the heat-shock temperature nor decreasing the severity of chilling (i.e., temperature and duration of exposure) significantly reduced chilling injury.

scholarly journals Heat Shocks Reduce Chilling Sensitivity of Cotton, Kenaf, Okra, and Rice Seedling Radicles

2000 ◽  
Vol 125 (3) ◽  
pp. 377-382 ◽  
Author(s):  
Mary E. Mangrich ◽  
Mikal E. Saltveit
Keyword(s):  
Heat Shock ◽  
Chilling Injury ◽  
Rice Seedling ◽  
Hibiscus Cannabinus ◽  
Wheat Seedlings ◽  
Chilling Sensitivity ◽  
Heat Shocks ◽  
Chilling Temperatures ◽  
Hibiscus Esculentus ◽  
Triticum Sativum

Seeds of cotton (Gossypium hirsutum L.), kenaf (Hibiscus cannabinus L.), okra [Abelmoschus esculentus (L.) Moench. `Clemson Spineless' (syn. Hibiscus esculentus L.)], rice (Oryza sativa L.), and wheat (Triticum sativum (L.) Lam.) were germinated and grown at 25 °C until their radicles reached 10 mm in length. They were then exposed to chilling temperatures for 0 to 5 days followed by 3 days at 25 °C. Radicle length was measured periodically and inhibition of elongation was used as an indicator of the severity of chilling injury. Exposure to chilling reduced radicle elongation in all species except chilling insensitive wheat. When seedlings were heat-shocked at 45 °C for 1 to 12 min before being chilled, radicles of the chilling sensitive okra, kenaf, cotton, and rice seedlings elongated more than seedlings not heat-shocked before chilling. The method of heat-shock application and the stringency (i.e., time× temperature) of the heat-shock and chilling treatments all affected the response of the tissue. In comparison to nonheat-shocked wheat seedlings, the radicles of chilling insensitive wheat seedlings did not elongate more than seedlings in which the heat shocks were applied before chilling. A brief heat shock ameliorates chilling injury in these chilling sensitive species.

scholarly journals Heat-shock Treatments Increase the Chilling Tolerance of Harvested Asparagus Spears

HortScience ◽  
2017 ◽  
Vol 52 (11) ◽  
pp. 1563-1568
Author(s):  
Mikal E. Saltveit
Keyword(s):  
Heat Shock ◽  
Chilling Injury ◽  
Chilling Tolerance ◽  
Bathing Solution ◽  
Ion Leakage ◽  
Physiological Disorder ◽  
Apical Half ◽  
Excised Tissue ◽  
Stem Segments ◽  
Quality And Shelf Life

Holding harvested asparagus spears at non-freezing temperatures below 2.5 °C induces chilling injury (CI), a physiological disorder that reduces quality and shelf life. CI can be quantified by subjective visual parameters, or by objective measurements of the increased rate of ion leakage from excised tissue into an isotonic bathing solution. The rate of ion leakage from apical (2–3 cm), middle (9–10 cm), and basal (15–16 cm) segments excised from 18-cm asparagus spears increased after 7 days of chilling at 2.5 °C. The increase continued and was similar for middle and basal segments after 14 days of chilling, but more pronounced from apical segments. Various heat-shock treatments (i.e., combinations of temperature and duration) decreased the chilling-induced increase in ion leakage from these 1-cm stem segments. Although the chilling tolerance of all spear segments was increased by specific heat-shock treatments, the optimal temperature and duration of exposure varied among the segments; some treatments that were effective in segments from one location were either ineffective or damaging to segments from another location. As the apical half of the whole spear is the predominant culinary portion and contains the most chilling sensitive tissue, heat-shock treatments that would increase the chilling tolerance of the upper half of whole spears were selected for further study. These heat-shock treatments were applied to freshly harvested whole 18-cm asparagus spears that were chilled at 2.5 °C for 14 days. Two treatment combinations (i.e., 45 °C for 4.0 ± 0.6 minutes or 50 °C for 2.9 ± 0.8 minutes) were identified that maintained the highest level of quality and significantly reduced the rate of chilling-induced ion leakage.

scholarly journals The Effect of Heat Shock, ABA, and Salicylic Acid on Induction of Chilling Tolerance in Cucumber Seedling Roots

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 913H-914
Author(s):  
Meng-Yee Tee ◽  
Paul H. Jennings
Keyword(s):  
Salicylic Acid ◽  
Heat Shock ◽  
Chilling Injury ◽  
Chilling Tolerance ◽  
Cucumber Seedling ◽  
Crop Species ◽  
Growth Effects ◽  
Seedling Roots ◽  
Treatment Mechanisms ◽  
Germinated Seeds

Chilling injury can be a serious problem during field germination of sensitive crop species. Because heat shock has been shown to induce chilling tolerance of germinating cucumber seeds, an experiment was initiated to determine the effectiveness of other treatments. Cucumber seeds germinated 20 to 24 h were either heat-shocked at 50C for 2 min or treated with ABA or salicylic acid for 4 h. Following treatment, the germinated seeds were chilled at 2C for 96, 120, or 144 h and then incubated at 25C to determine growth effects on the developing root. All treatments induced chilling tolerance compared to the controls, with ABA and heat shock being most effective after chilling. There did not appear to be an additive response when heat shock was used in combination with ABA. The evidence for different treatment mechanisms will be discussed.

scholarly journals Duration and Persistence of Heat Shock Induction of Chilling Tolerance in Cucumber Seedling Roots

HortScience ◽  
1997 ◽  
Vol 32 (3) ◽  
pp. 538E-538
Author(s):  
Hua Zhang ◽  
Paul H. Jennings
Keyword(s):  
Heat Shock ◽  
Root Growth ◽  
Electrolyte Leakage ◽  
Chilling Tolerance ◽  
Shock Duration ◽  
Dependent Manner ◽  
Heat Shocks ◽  
Shock Proteins ◽  
Membrane Peroxidation ◽  
Heat Shock Induction

The effects of heat shock duration and persistence on the induction of chilling tolerance in cucumber roots were studied using total root growth, electrolyte leakage, and membrane peroxidation as injury indices after chilling. Heat shock reduced the chilling induced electrolyte leakage, decreased membrane peroxidation as measured by MDA content, and resulted in a greater total root growth after chilling compared to the control. Heat shocks at 40°C, applied to 36 hr germinated seedlings for time periods from 1 to 15 hr, all resulted in an increase in chilling tolerance in a time-dependent manner. The heat shock induction of chilling tolerance is most effective when heat shock was imposed immediately before chilling, but the effect is persistent even 32 hr after heat shock when seedlings are held at 25°C before chilling. The possible mechanism of heat shock effect and its persistence will be discussed in relation to heat shock proteins and antioxidant enzyme systems.

scholarly journals Are the Effects of Heat on Physiology Due to Heat Shock Proteins?

HortScience ◽  
1996 ◽  
Vol 31 (4) ◽  
pp. 691c-691
Author(s):  
Robert E. Paull ◽  
Chris B. Watkins
Keyword(s):  
Heat Shock ◽  
Heat Shock Proteins ◽  
Stress Responses ◽  
Critical Role ◽  
Chilling Injury ◽  
Heat Treatments ◽  
Adaptation To Heat ◽  
Heat Shock Responses ◽  
Shock Proteins

Production of heat shock proteins (HSP) in response to high temperatures are a highly recognizable feature of plant and animal systems. It is thought that such proteins play a critical role in survival under supraoptimal temperature conditions. The use of heat treatments has been examined extensively, especially for disinfestation of fruit and disease control. Heat treatments can affect physiological responses, such as ethylene production, softening, and other ripening factors, as well as reducing physiological disorders, including chilling injury. HSPs have been implicated in a number of stress responses, but the extent that they are involved, especially in amelioration of chilling injury, is a subject of debate. In a number of cases, heat shock proteins do not appear to be involved, and HSPs do not explain long-term adaptation to heat; other systems for which we do not have models may be at work. Resolution of these issues may require the use of transgenic plants with modified heat shock responses.

The contribution of biotechnology to improving post-harvest chilling tolerance in fruits and vegetables using heat-shock proteins

2013 ◽  
Vol 153 (1) ◽  
pp. 7-24 ◽  
Author(s):  
M. S. AGHDAM ◽  
L. SEVILLANO ◽  
F. B. FLORES ◽  
S. BODBODAK
Keyword(s):  
Heat Shock ◽  
Heat Shock Proteins ◽  
Plant Species ◽  
Fruits And Vegetables ◽  
Chilling Injury ◽  
Chilling Tolerance ◽  
Refrigerated Storage ◽  
Post Harvest ◽  
Injury Tolerance ◽  
Shock Proteins

SUMMARYFresh fruits and vegetables have a short post-harvest life and are prone to post-harvest losses due to mechanical injury, physiological causes and decay. Low-temperature storage is widely used as post-harvest treatment applied for delaying senescence in vegetables and ornamentals and ripening in fruits, upholding their post-harvest quality. But the refrigerated storage of tropical and subtropical crop plant species provokes a set of physiological alterations known as chilling injury that negatively affect their quality and frequently renders the product not saleable. Membrane damage and reactive oxygen species (ROS) accumulation are the main adverse effects of chilling injury impact in sensitive horticultural products. The chilling injury tolerance of certain plant species is attributed to their ability to accumulate heat-shock proteins (HSP). The beneficial action of HSP in chilling tolerance is due to their chaperone activity but, besides this biological function, small HSP (sHSP) are able to function as membrane stabilizers and ROS scavengers, or synergistically with cell antioxidant systems. Also, biosynthesis of osmolytes such as raffinose and proline is under the regulation of heat-shock transcription factors (HSTF). These molecules are critical for osmotic adjustment since low temperatures also provoke a secondary osmotic stress. The use of biotechnological strategies can be envisaged, with the aim of generating engineered crop plants of horticultural interest to induce the production and action of HSP and HSTF, in order to assure the beneficial effects of these proteins in promoting chilling injury tolerance during their post-harvest refrigerated storage. In particular, induction of HSTF expression using biotechnology has significant potential and interest for reducing the impact of chilling injury on sensitive produce, avoiding the practical difficulties of applying the classic post-harvest technologies based on heat treatment.

scholarly journals 474 Effect of Vigor and Duration of Chilling on Heat Shock-induced Chilling Tolerance in Cucumber Radicles

HortScience ◽  
1999 ◽  
Vol 34 (3) ◽  
pp. 526D-526
Author(s):  
Mary E. Mangrich ◽  
Mikal E. Saltveit
Keyword(s):  
Heat Shock ◽  
Cucumis Sativus ◽  
Chilling Stress ◽  
Chilling Tolerance ◽  
Subsequent Growth ◽  
Radicle Growth ◽  
Linear Decrease ◽  
Heat Shocks

Chilling 10-mm cucumber (Cucumis sativus L. `Poinsett 76') radicles at 2.5 °C reduced their subsequent growth during 3 days at 25 °C. The reduction in radicle growth was linear for 1 to 3 days of chilling but then increased substantially until subsequent radicle growth was all but eliminated by 6 days of chilling. Heat shocks of 40 °C applied for 4 to 12 min increased chilling tolerance such that 4 days of chilling caused only a 36% decrease in radicle growth compared to 66% for seedlings not heat shocked, which brought the response in line with the responses of the non-heat-shocked seeds chilled for 1 to 3 days. Eight-minute heat shocks applied before 5 days of chilling resulted in a 45% inhibition of subsequent growth, compared to 82% for chilled non-heat-shocked controls. Heat shocks applied before 3 days of chilling did not result in a significant increase in subsequent growth compared to the non-heat-shocked controls chilled for 3 days. Heat shocks were only able to protect that part of radicle growth that was in excess of the linear decrease in radicle growth. There appears to be two effects of chilling on radicle growth. The first is linear and cannot be affected by heat shocks. The second is much more severe and can be prevented by heat shocks. Seeds were selected for three categories of vigor according to the rate at which their radicles grew to 10 mm. Seeds classified with different vigors neither responded significantly differently to 3 days exposure to 2.5 °C nor did they respond differently to chilling stress following application of heat shocks.

scholarly journals Oxidative Stress and Chilling Tolerance in Tomato Seedlings

HortScience ◽  
1996 ◽  
Vol 31 (4) ◽  
pp. 645b-645
Author(s):  
Kanogwan Kerdnaimongkol ◽  
Anju Bhatia ◽  
Robert J. Joly ◽  
William R. Woodson
Keyword(s):  
Oxidative Stress ◽  
Hydrogen Peroxide ◽  
Superoxide Dismutase ◽  
Diurnal Variation ◽  
Chilling Stress ◽  
Chilling Injury ◽  
Chilling Tolerance ◽  
Light Period ◽  
Tomato Seedlings ◽  
Chilling Sensitivity

Diurnal variation in the chilling sensitivity of tomato seedlings was examined. Sensitivity to chilling in tomato seedlings is a response to light and not under the control of a circadian rhythm. Chilling sensitivity is highest in seedlings chilled at the end of the dark period, and these seedlings become more resistant to chilling injury upon exposure to the light. Diurnal variation in chilling sensitivity was associated with changes in catalase and superoxide dismutase activities. The results show an increase in catalase and superoxide dismutase activities at the end of the light period. The recovery of the net photosynthesis rate following chilling was faster in seedlings chilled at the end of the light period. It is suggested that an increase in catalase and superoxide dismutase activities at the end of light period before the chilling plays a role in the resistance to chilling stress in tomato seedlings. Forty-eight hours of 14°C acclimation or hydrogen peroxide pretreatment conferred chilling tolerance to tomato seedlings and were correlated with elevated catalase activity. Acclimated seedlings still exhibited diurnal variation in chilling sensitivity while hydrogen peroxide treated seedlings showed little evidence of a diurnal variation in chilling sensitivity. Transgenic tomato plants expressing an antisense catalase gene were generated. A several-fold decrease in total catalase has been detected in the leaf extracts of transformants. Preliminary analysis of these plants indicated that modification of reactive oxygen species scavenging in plant system can lead to change in oxidative stress tolerance.

Sign in / Sign up

Export Citation Format

Share Document