ICAR Research Data Repository for Knowledge Management
Regulation of Flower Senescence by Abscisic Acid (ABA) in Gladiolus (Gladiolus grandiflora Hort.)
KrishiKosh
View Archive Info| Field | Value | |
| Title |
Regulation of Flower Senescence by Abscisic Acid (ABA) in Gladiolus (Gladiolus grandiflora Hort.)
Ph.D. |
|
| Creator |
MADAN KUMAR
|
|
| Contributor |
Singh, V. P.
|
|
| Subject |
developmental stages, aba, enzymes, gladiolus, acidity, planting, ethylene, solutes, harvesting, genes
|
|
| Description |
Gladiolus flowers are ethylene insensitive and the signals that start catabolic changes during senescence of gladiolus flower are largely not known. Basic of senescence in this flower has long stayed as a mystery and we proposed that ABA might be a key player in this process. Therefore, experiments were performed to understand the role of abscisic acid (ABA) in floral senescence of gladiolus (Gladiolus grandiflora Hort.) flower. It was observed that ABA accumulation increased in attached petals of gladiolus flowers as they senesced. Exogenous application of ABA in vase solution accelerated senescence process in the flowers due to change in various senescence indicators such as enhanced membrane leakage, reduced water uptake, reduced fresh weight and ultimately vase life. ABA (100 μM) also accelerates the senescence process by enhancing the biochemical changes such as lipoxygenase, lipid peroxidation, protease, RNase and DNase activity. On the contrary the antioxidant enzymes activity has been reduced viz., superoxide dismutase, catalase, peroxidase, ascorbate peroxidase, glutathione reductase and also decreases total protein content in petal tissue. Enhancement of In vivo ABA level in petals by creating osmotic stress also up regulates the same parameters of flower senescence as those occurring during natural senescence and also akin to exogenous application of ABA. Vase life of gladiolus flowers could be altered by application of putative ABA biosynthesis inhibitor fluridone in vase solution. Perhaps high level of carotenoids already present in the petal was probably sufficient to provide ample substrate for ABA synthesis. In contrast, ABA action was mitigated by application of GA3 in holding solution along with Abscisic acid which is basically an antagonist of ABA action. Furthermore, our finding has provided the initial evidence that, supplementation of gibberellic acid (GA3) in the vase solution having ABA reversed various senescence related parameters which were down or upregulated by ABA proving role of ABA in senescence of gladiolus flowers. Further, gene expression analysis showed that the expression of GgCyP1 was up regulated and DAD1 was down regulated, whereas the ethylene receptor genes (GgERS1a and GgERS1b) were not significantly influenced in ABA treated flowers as compared to control.
|
|
| Date |
2016-03-10T19:51:19Z
2016-03-10T19:51:19Z 2013 |
|
| Type |
Thesis
|
|
| Identifier |
http://krishikosh.egranth.ac.in/handle/1/65062
|
|
| Language |
en_US
|
|
| Format |
application/pdf
|
|
| Publisher |
IARI, DIVISION OF PLANT PHYSIOLOGY, NEW DELHI
|
|