Low Temperature Stress Physiology in Crops

P.H. Li

• Publisher: CRC Press
• Year: 2018
• ISBN:
  9781351091084
• Edition: 1
• Topic: Biological Sciences
• Subtopic: Biology
• Index: Biological Sciences

The importance of low temperature stress physiology research has become increasingly apparent in agriculture for productions of food, fibre and ornamental plants. This volume consists of two parts, there are a total of 14 chapters including 6 chapters dealing with cold accumulation related topics, 6 dealing with freeze stress and 2 related to ethylene production and mefluidide protection.

Responses of Chilling-Insensitive Plants to Low Temperature Stress

Chapter 1

The Induction of Cold Acclimation: The Role of Abscisic

Martin J. T. Reaney, Masaya Ishikawa, Albert J. Robertson and L. V. Gusta

TABLE OF CONTENTS

I. Introduction

II. Role of Growth Regulators in Cold Acclimation

A. Evidence for Translocatable Hardiness Promoters and Inhibitors

B. Endogenous ABA

C. Exogenous ABA

D. Gibberellins

E. Auxins

F. Cytokinins

G. Growth Regulators

III. Cross Adaptation

IV. Aba Responses

V. The Induction of Freezing Tolerance in Bromegrass Suspension Cultures by ABA

A. Factors Affecting ABA Induced Cold Hardening

1. Inoculum Weight

2. The Effect of ABA Concentration

3. Incubation Temperature

4. Ethanol

5. Miscellaneous Faclors

6. Gibberellic Acid Effects on ABA-Induced Freezing Tolerance

7. Dehardening of ABA-Induced Cultures

8. The Effect of Sucrose On the ABA Induced Cold Hardening

B. ABA-Induced Tolerance to Salt, Heat, and Osmotic Stresses

C. Morphological Cell Changes Induced by ABA

D. ABA and Low Temperature Induced Proteins

VI. Concluding Remarks

References

I. Introduction

The induction of freezing and chilling tolerance in temperate plant species requires a sensory mechanism for detecting environmental cues. The cue may be a stress or an environmental change, e.g., photoperiod. In response to the cues, metabolism switches from growth promotion to growth cessation. Short days at warm temperatures or low temperatures, or low temperatures alone are known to induce cold acclimation in temperate species.¹ Leaves perceive photoperiodic changes but the sensory mechanism is not known,² although phytochrome has been suggested to be involved.³ There is considerable evidence that environmentally controlled, endogenous growth regulators such as abscisic acid (ABA) and gibberellic acid (GA) are involved in the adaptive response.

II. Role of Growth Regulators in Cold Acclimation

A. Evidence for Translocatable Hardiness Promoters and Inhibitors

The leaves of woody plants produce both translocatable hardiness inhibitors ^2,4 and translocatable hardiness promoters^2,4,5 depending upon the environmental cues. Irving and Lamphear^4,5 demonstrated that leaves of Acer negundo exposed to long days produced cold hardiness inhibitors which had GA-like activity, whereas extracts from leaves of plants exposed to short days had ABA-like activity.⁴ Plants exposed to natural short days in the fall cold hardened, but plants receiving an extended photoperiod of 6 hr did not harden until the leaves were killed by a frost. Fuchigami² reported leaves of Cornus sericea growing at 15 to 20°C produced translocatable inhibitors of hardiness under long days and translocatable promoters of hardiness under short days. Removal of leaves from C. sericea exposed to long days enhanced acclimation, whereas removal of leaves from plants exposed to short days inhibited acclimation. A single defoliated branch of C. sericea hardened to the same level as the plant’s remaining branches exposed to short days and low temperatures. However, the defoliated branch failed to acclimate when girdled at the base. In a continuing study,² two climatic clones of C. sericea, differing in time and rate of acclimation, were side grafted and pruned to two leaders. The grafted branches acclimated at the same rate as the parent clones. If the branch of the slow acclimating clone was defoliated, its acclimation rate increased, but it did not harden as rapidly or to the same extent as foliated branches from the fast acclimating clone. If the foliated, fast acclimating branch was girdled at the base, the rate and degree of acclimation of the defoliated, slow acclimating branch was reduced. In a reciprocal study, branches of the fast acclimating clone were defoliated, resulting in a decreased rate of acclimation. The above results suggest a translocatable hardiness promoters) is produced in leaves exposed to short days and translocatable hardiness inhibitor(s) is produced in leaves exposed to long days. The balance of the promoters and inhibitors may be more critical for hardening rather than the concentrations of the components involved.

Wheat leaves exposed to light at 2°C produced a cold hardiness promoter which was translocated to underground tillers of winter wheat (Triticum aestivum).⁶ Plants exposed to light for as little as 15 min/day at 2°C hardened, whereas plants kept in total darkness did not. Tillers maintained in the dark hardened if the remainder of the plant was kept in the light at 2°C. In contrast, Shayakhmetova et al.⁷ found that illuminated wheat leaves did not confer hardiness to leaves maintained in the dark. Limin and Fowler⁸ reported that winter wheat leaves and crowns held at warm, nonhardening temperatures cold hardened if the roots were exposed to cool temperatures. However, if the leaves were maintained at low temperatures and the roots at warm temperatures, the leaves hardened but the crowns did not. Fayyaz et al.⁹ found that a combination of short photoperiod and low air and soil temperature induced maximum cold hardiness in Chrysanthemum morifolium rhizomes. A long photoperiod, warm aerial temperatures, and low soil temperature did not induce rhizome hardening. Some hardening did occur in cool soils with either short photoperiods or low aerial temperatures. Therefore, the induction of rhizome hardening is dependent, in part, upon a stimulus translocated from the aerial to the below ground parts.

These translocatable hardiness promoters and inhibitors were not identified by the above authors. Several authors have suggested that ABA and GA may be the endogenous hardiness promoter and inhibitor, respectively.

B. Endogenous ABA

Irving and Lamphear^4,5 were among the first to suggest that ABA was the translocatable hardiness promoter. Higher levels of “dormin” or ABA were extracted from short-day induced A. negundo plants than from long day grown plants. Similarly, Mielke and Dennis¹⁰ demonstrated an increase in ABA in Prunus cerasus L. in the autumn. When trees were mechanically defoliated prior to the onset of leaf abscission, no measurable increase in ABA was detected. The intracellular levels of ABA in the very hardy winter wheat cultivar Kharkov were threefold higher than in the less hardy cultivar Cappelle.¹¹ Exposure of winter rape seedlings to cold hardening conditions resulted in an increase in ABA.¹² However, Waldman et al.¹³ found no difference in the ABA—like activity in fully hardened and nonhardened alfalfa (Medicago sativa). Daie et al.¹⁴ measured an increase in ABA, hydrolyzable ABA and dihydrophaseic acid (DPA) in five warm season crops, but not in five cool season crops which were grown initially at 25°C and then exposed to 10°C. Chen and Li¹⁵ reported a transitory threefold increase in ABA in the hardy potatoe species, Solanum commersoni, but not in the tender species S. tuberosum during the first 4 days exposure to hardening conditions. After 4 days, the level of ABA returned to its original level. In potato, ABA increased only in hardy species and only during the initial stages of hardening. This may explain why some researchers have not detected increases in endogenous ABA during hardening.

C. Exogenous ABA

Exogenous application of ABA to induce cold acclimation or chilling resistance has resulted in either no response, partial enhancement, or a dramatic increase. Irving and Lamphear¹⁶ hardened twigs of A. negundo from − 15° to −21.4°C by inserting leaves into vials containing a high concentration of ABA (100 mg/ℓ). Fuchigami et al.,² using a similar method, found no ABA enhancement of hardiness in C. sericea. Fayyaz et al.⁹ could not induce hardening with ABA in Chrysanthemum morifolium rhizomes either at warm or cool temperatures. Gusta et al.¹⁷ found that ABA inhibited growth but had little or no effect on enhancing freezing resistance of winter wheat crowns, when applied as a foliar spray or in the nutrient hydroponics solution to the roots. In contrast, Larson¹⁸ increased the crown hardiness of Norstar winter wheat 12°C by an exogenous application of ABA to wheat seedlings at the two to three leaf stage. These plants were grown on agar under sterile conditions for 9 days in the presence of 7.5 × 10⁻⁵ M ABA. Plants exposed to 2°C hardened slightly faster in the presence of ABA compared to the controls, but the ultimate level of hardiness attained was similar. ABA was shown to prevent chilling injury in cotton (Gossypium hir...

Table of contents

• Cover
• Title Page
• Copyright Page
• Preface
• The Editor
• Contributors
• Table of Contents
• Part I. Responses of Chilling-Insensitive Plants to Low Temperature Stress
• Part II. Responses of Chilling-Sensitive Plants to Low Temperature Stress
• Index