Next Article in Journal
New Insights into the Use of Rhizobia to Mitigate Soil N2O Emissions
Previous Article in Journal
Soil Aeration and Plastic Film Mulching Increase the Yield Potential and Quality of Tomato (Solanum lycopersicum)
Previous Article in Special Issue
Managing Crop Load in European Pear (Pyrus communis L.)—A Review
Article

The Impact of Dormancy Breakers on Hormone Profiles, Fruit Growth and Quality in Sweet Cherry

1
Tasmanian Institute of Agriculture, University of Tasmania, Private Bag 98, Hobart, TAS 7001, Australia
2
School of Natural Sciences, University of Tasmania, Private Bag 55, Hobart, TAS 7001, Australia
3
Central Science Laboratory, University of Tasmania, Private Bag 74, Hobart, TAS 7001, Australia
4
Department of Agriculture and Fisheries, Regional Economic Development, Mackay, QLD 4740, Australia
*
Author to whom correspondence should be addressed.
Academic Editor: Martin Weih
Agriculture 2022, 12(2), 270; https://doi.org/10.3390/agriculture12020270
Received: 9 November 2021 / Revised: 11 February 2022 / Accepted: 11 February 2022 / Published: 14 February 2022
Chemical dormancy breakers are often used to manipulate floral bud break in sweet cherry production, and their use is increasing due to unpredictable climate effects. The role of plant hormones in regulating the critical transition of floral buds from dormant to opening in deciduous trees is now emerging. By monitoring changes in endogenous hormone levels within floral buds that are undergoing the transition from dormant to the growing state in response to various cues (environmental and/or chemical inducers), we can begin to distinguish the plant hormones that are the drivers of this process. This study sought to identify key hormonal regulators of floral bud break using sweet cherry as a model and modifying timing of bud break through the application of two chemical dormancy breakers, hydrogen cyanamide (HC, Dormex®) and emulsified vegetable oil compound (EVOC, Waiken®), and to determine the effect of these chemicals on fruit growth and quality. Treatments were applied at label rates 35–40 days before estimated bud break. We found that HC-treated tree buds broke earlier, and this was associated with a significant early elevation of the cytokinins dihydrozeatin and dihydrozeatin riboside compared to the control and EVOC-treated tree buds. In contrast, changes in auxin and abscisic acid content did not appear to explain the hastened bud burst induced by hydrogen cyanamide. While HC-treated trees resulted in larger fruit, there was a higher incidence of cracked fruit and the pack-out of A-grade fruit was reduced. The increase in fruit size was attributed to the earlier flowering and hence longer growing period. Harvest assessment of fruit quality showed no treatment effect on most quality parameters, including fruit dry matter content, total soluble solids or malic acid content, but a reduction in fruit compression firmness and stem pull force in EVOC-treated trees was observed. However, all fruit still met the Australian industry fruit quality export market standards. This study offers important insights into bud hormonal activities underpinning the action of these chemical regulators; understanding bud responses is critically important to ensuring consistent and sustainable fruit tree production systems into the future. It also demonstrates that the dormancy-breaking agents HC and EVOC have no detrimental impact on fruit quality at harvest or following storage, however growers need to be aware of the potential for increased fruit cracking when earlier bud break results in a longer growing season which has the potential to increase fruit size. Further studies are required to determine the role of gibberellin in hastening bud break by dormancy breakers. View Full-Text
Keywords: abscisic acid; auxin; bud break; cytokinin; hydrogen cyanamide; emulsified vegetable oil compound; fruit firmness; soluble solids; stem retention abscisic acid; auxin; bud break; cytokinin; hydrogen cyanamide; emulsified vegetable oil compound; fruit firmness; soluble solids; stem retention
Show Figures

Figure 1

MDPI and ACS Style

Bound, S.A.; Foo, E.; Gélinas-Marion, A.; Nichols, D.S.; Nissen, R. The Impact of Dormancy Breakers on Hormone Profiles, Fruit Growth and Quality in Sweet Cherry. Agriculture 2022, 12, 270. https://doi.org/10.3390/agriculture12020270

AMA Style

Bound SA, Foo E, Gélinas-Marion A, Nichols DS, Nissen R. The Impact of Dormancy Breakers on Hormone Profiles, Fruit Growth and Quality in Sweet Cherry. Agriculture. 2022; 12(2):270. https://doi.org/10.3390/agriculture12020270

Chicago/Turabian Style

Bound, Sally A., Eloise Foo, Ariane Gélinas-Marion, David S. Nichols, and Robert Nissen. 2022. "The Impact of Dormancy Breakers on Hormone Profiles, Fruit Growth and Quality in Sweet Cherry" Agriculture 12, no. 2: 270. https://doi.org/10.3390/agriculture12020270

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop