Dormancy Release in Deciduous Fruit Trees

Saure, M.

doi:10.1002/9781118060735.ch6

Cited by 164 publications

(157 citation statements)

References 144 publications

Supporting

Mentioning

133

Contrasting

Unclassified

Order By: Relevance

“…Studies on winter chill and chilling requirements often implicitly assume that all models can be used interchangeably because the choice of model is not important. 27 However, many studies have shown that the choice of model is very important. 28 The Richardson and Infruitec models accumulate in a similar manner; the accumulation table is set out in Table 3.…”

Section: Impact Of Climate Change On Chill Unit Accumulationmentioning

confidence: 99%

simulation study on the effect of climate change on crop water use and chill unit accumulation

Ogundeji¹,

Jordaan²

2017

S. Afr. J. Sci.

View full text Add to dashboard Cite

Climate change and its impact on already scarce water resources are of global importance, but even more so for water scarce countries. Apart from the effect of climate change on water supply, the chill unit requirement of deciduous fruit crops is also expected to be affected. Although research on crop water use has been undertaken, researchers have not taken the future climate into consideration. They also have focused on increasing temperatures but failed to relate temperature to chill unit accumulation, especially in South Africa. With a view of helping farmers to adapt to climate change, in this study we provide information that will assist farmers in their decision-making process for adaptation and in the selection of appropriate cultivars of deciduous fruits. Crop water use and chill unit requirements are modelled for the present and future climate. Results show that, irrespective of the irrigation system employed, climate change has led to increases in crop water use. Water use with the drip irrigation system was lower than with sprinkler irrigation as a result of efficiency differences in the irrigation technologies. It was also confirmed that the accumulated chill units will decrease in the future as a consequence of climate change. In order to remain in production, farmers need to adapt to climate change stress by putting in place water resources and crop management plans. Thus, producers must be furnished with a variety of adaptation or management strategies to overcome the impact of climate change.

show abstract

Section: Impact Of Climate Change On Chill Unit Accumulationmentioning

confidence: 99%

simulation study on the effect of climate change on crop water use and chill unit accumulation

Ogundeji¹,

Jordaan²

2017

S. Afr. J. Sci.

View full text Add to dashboard Cite

show abstract

“…During dormancy, visible growth is suspended but developmental changes can still occur (Saure, 1985) and buds are physiologically and biochemically active.…”

Section: Introductionmentioning

confidence: 99%

Effect of Dormex, Fructose and Methionine Spraying on Bud Dor-mancy Release of "Superior" Grapevines

2017

AJAS

View full text Add to dashboard Cite

This study was carried out during the two successive seasons 2015 and 2016 on 13 years old "Superior" grapevines to study the effect of spraying fructose (3, 5%), methionine (3, 5%) and hydrogen cyanamide 5% (Dormex) on bud dormancy release of "Superior" grapevines. Cyanamide is frequently used for grape bud dormancy release. However, those chemicals are potentially harmful to humans. In this study, we used substances that are less toxic to the environment and grape growers, such as fructose and methionine to determine their effects on "Superior" grape bud break. All treatments significantly improved the percentage of bud break, fruiting buds and yield, as well as the advancement of the harvest date and improving the berry quality compared to untreat ones (control). Also, all treatments induce gradually increased bud contents of IAA and GA 3 and a gradual decrease of ABA from treated date towards buds burst compared to untreated ones. Dormex spraying gave the highest values of studied traits compared to other treatments. No significant differences were found among 5% dormex and 3% fructose spraying. Hence, 3% fructose shows potential for use as a commercial bud break and improves superior grapes fruiting.

show abstract

“…The reproductive and vegetative buds of temperate trees become dormant in autumn and require exposure to winter chill, of an amount specific to species and variety, to exit this state (Westwood 1993). Trees that are not exposed to enough winter cold, i.e., do not meet their "chilling requirement," have been reported to experience delayed, protracted, and weak leafing and flowering, formation of bare shoots, shortage of flower bud-bearing spurs, poor fruit development, and irregular ripening (Saure 1985). Lack of sufficient chill can cause structurally underdeveloped flower buds, undersized pistils, abortion of flower primordia, and abscission of flower buds in various stages of development (Black 1952).…”

Section: Introductionmentioning

confidence: 99%

Nut crop yield records show that budbreak-based chilling requirements may not reflect yield decline chill thresholds

et al. 2014

View full text Add to dashboard Cite

TitleNut crop yield records show that budbreak-based chilling requirements may not reflect yield decline chill thresholds Abstract Warming winters due to climate change may critically affect temperate tree species. Insufficiently cold winters are thought to result in fewer viable flower buds and the subsequent development of fewer fruits or nuts, decreasing the yield of an orchard or fecundity of a species. The best existing approximation for a threshold of sufficient cold accumulation, the "chilling requirement" of a species or variety, has been quantified by manipulating or modeling the conditions that result in dormant bud breaking. However, the physiological processes that affect budbreak are not the same as those that determine yield. This study sought to test whether budbreak-based chilling thresholds can reasonably approximate the thresholds that affect yield, particularly regarding the potential impacts of climate change on temperate tree crop yields. County-wide yield records for almond (Prunus dulcis), pistachio (Pistacia vera), and walnut (Juglans regia) in the Central Valley of California were compared with 50 years of weather records. Bayesian nonparametric function estimation was used to model yield potentials at varying amounts of chill accumulation. In almonds, average yields occurred when chill accumulation was close to the budbreak-based chilling requirement. However, in the other two crops, pistachios and walnuts, the best previous estimate of the budbreak-based chilling requirements was 19-32 % higher than the chilling accumulations associated with average or above average yields. This research indicates that physiological processes beyond requirements for budbreak should be considered when estimating chill accumulation thresholds of yield decline and potential impacts of climate change.

show abstract

Dormancy Release in Deciduous Fruit Trees

Cited by 164 publications

References 144 publications

simulation study on the effect of climate change on crop water use and chill unit accumulation

simulation study on the effect of climate change on crop water use and chill unit accumulation

Effect of Dormex, Fructose and Methionine Spraying on Bud Dor-mancy Release of "Superior" Grapevines

Nut crop yield records show that budbreak-based chilling requirements may not reflect yield decline chill thresholds

Contact Info

Product

Resources

About