ABSTRACT
Abstract ................................................................................................. 181 5.1 Introduction .................................................................................. 181 5.2 Chemical Structure ....................................................................... 182 5.3 Biosynthesis ................................................................................. 182 5.4 Translocation ................................................................................ 183 5.5 Functions ...................................................................................... 184 5.6 Commercial Availability .............................................................. 185 5.7 Role of Gibberellins in Improving and
Maintaining Postharvest Quality of Fruit Crops .......................... 185 5.7.1 Parthenocarpy ................................................................... 185 5.7.1.1 Apple ................................................................. 185 5.7.1.2 Pear .................................................................... 186
5.7.1.3 Mango ............................................................... 187 5.7.1.4 Guava ................................................................ 187 5.7.1.5 Citrus ................................................................. 188 5.7.1.6 Vegetables .......................................................... 189 5.7.2 Fruit Set .......................................................................... 189 5.7.3 Control of Fruit Drop ..................................................... 191 5.7.4 Fruit Size ........................................................................ 191 5.7.5 Fruit Weight .................................................................... 192 5.7.6 Physiological Loss in Weight ......................................... 192 5.7.7 Fruit Volume ................................................................... 193 5.7.8 Fruit Color ...................................................................... 193 5.7.9 Fruit Firmness ................................................................ 194 5.7.10 Fruit Yield....................................................................... 195 5.7.11 TSS ................................................................................. 195 5.7.12 Titrable Acidity ............................................................... 196 5.7.13 Sugars ............................................................................. 197 5.7.14 Ascorbic Acid ................................................................. 198 5.7.15 Storage Life .................................................................... 198 5.7.16 Spoilage .......................................................................... 199 5.7.17 Organoleptic Rating ....................................................... 200 5.7.18 Carotene Content ............................................................ 200 5.7.19 Total Phenols .................................................................. 200 5.7.20 Enzymatic Activity ......................................................... 201 5.7.21 Mode of Action in Relation to Anti-Ripening
and Delaying Senescence ............................................... 201 5.7.22 Effect of Gibberellins on Vegetables .............................. 201 5.7.23 Influence of GA on Plant Height and
Internodal Length of Flower Crops ................................ 203 5.7.24 Number of Stems ............................................................ 203 5.7.25 Flower Bud Emergence and Flower Harvesting ............ 204 5.7.26 Quality Attributes ........................................................... 204 5.7.27 Length of Stalk ............................................................... 207 5.7.28 Flower Length and Diameter ......................................... 208
5.7.29 Neck Length ................................................................... 209 5.7.30 Flower Yield ................................................................... 209 5.7.31 Vase Life ......................................................................... 213 5.7.32 Bent Neck in Gerbera ..................................................... 217 5.7.33 Disease Resistance in Rose ............................................ 217 5.7.34 Extra Points .................................................................... 218 Keywords .............................................................................................. 219 References ............................................................................................. 219
ABSTRACT
Research in the field of plant hormones is an interesting aspect of physiology where new research findings have been established every year. Plant hormones are synthesized in minute quantities in different plant parts with specific action on target tissues. They are synthesized artificially and applied in the horticultural industry to obtain desired results. Authors among the world had compiled their structure, synthesis, and mode of action. Literature regarding their utilization for quality produces after harvest is scanty. In this chapter, a brief introduction about the discovery, structure, synthesis and functions has been discussed. Interaction of gibberellins with other plant hormones and its role in maintaining postharvest quality of horticultural produce has been highlighted under various headings.
