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Cryotolerance of apple tree bud is independent of endodormancy.

Bilavcik A, Zamecnik J, Faltus M - Front Plant Sci (2015)

Bottom Line: The cryosurvival of vegetative apple buds of both cultivars correlated with their cold hardening without direct regard to their particular phase of dormancy.Both cultivars had the highest cryosurvival in December and January.The presented data were compared with our previous results from a dormancy study of in vitro apple culture.

View Article: PubMed Central - PubMed

Affiliation: Plant Physiology and Cryobiology Laboratory, Crop Research Institute Prague, Czech Republic.

ABSTRACT
Increasing interest in cryopreservation of dormant buds reveals the need for better understanding of the role of dormancy in cryotolerance. Dormancy stage and low-temperature survival of vegetative apple buds (Malus domestica Borkh.), cultivars 'Sampion' and 'Spartan', collected from orchard were evaluated during three seasons contrasting in temperature and precipitation throughout the arrested plant growth period. During each season, the cultivars differed either in the onset of the endodormancy or in the length of the endodormant period. A simple relation between endodormancy of the buds and their water content was not detected. The cryosurvival of vegetative apple buds of both cultivars correlated with their cold hardening without direct regard to their particular phase of dormancy. The period of the highest bud cryotolerance after low-temperature exposure overlapped with the endodormant period in some evaluated seasons. Both cultivars had the highest cryosurvival in December and January. The presented data were compared with our previous results from a dormancy study of in vitro apple culture. Endodormancy coincided with the period of successful cryosurvival of apple buds after liquid nitrogen exposure, but as such, it was not decisive for their survival and did not limit their successful cryopreservation.

No MeSH data available.


Related in: MedlinePlus

Average survival from three seasons of 1998/1999, 1999/2000, and 2000/2001 of vegetative buds of apple cultivars ‘Sampion’ and ‘Spartan’ after the first step of cryopreservation protocol at –30°C (A), and after the second step, reaching the LN temperature (B). ND variant was cryopreserved immediately after sampling from the orchard. D variant was cryopreserved after frost dehydration of at least 1 week at –4°C. Survival was tested by examination of oxidative browning of tissues on the longitudinal cut of the bud. Water content was measured immediately before cryopreservation procedure. Bars indicate SD (p < 0.05).
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Figure 7: Average survival from three seasons of 1998/1999, 1999/2000, and 2000/2001 of vegetative buds of apple cultivars ‘Sampion’ and ‘Spartan’ after the first step of cryopreservation protocol at –30°C (A), and after the second step, reaching the LN temperature (B). ND variant was cryopreserved immediately after sampling from the orchard. D variant was cryopreserved after frost dehydration of at least 1 week at –4°C. Survival was tested by examination of oxidative browning of tissues on the longitudinal cut of the bud. Water content was measured immediately before cryopreservation procedure. Bars indicate SD (p < 0.05).

Mentions: After the first step of the cryopreservation (to –30°C) both cultivars had the highest survival in December contrary to the lowest bud survival in September (Figure 7A). The differences in survival were found either between individual apple cultivars or between ND and D variants in each cultivar. Dehydrated buds of both cultivars showed a higher frost survival after –30°C, after the first step of cryopreservation protocol. It was mainly in October and November, when the buds were not cold acclimated yet. The used dehydration procedure enhanced cold acclimation. The maximal survival after the first cooling to –30°C was prerequisite for the following second step of the cryopreservation protocol. Cold hardiness, acquired either early in the dormant season during good acclimation conditions (Stushnoff, 1991) or later in winter after reacclimation at artificial storage at –4°C (Forsline et al., 1998), is considered a key step for successful cryopreservation. This is in consistence with our results (Figure 7). Aronen and Ryynanen (2014) found in hybrid aspen that the time schedule for cryopreservation of dormant buds could be extended from mid-winter to late autumn without compromising the recovery of the cryostored material. From October to February, on average, over 75% of their cryopreserved buds could be regenerated by micropropagation.


Cryotolerance of apple tree bud is independent of endodormancy.

Bilavcik A, Zamecnik J, Faltus M - Front Plant Sci (2015)

Average survival from three seasons of 1998/1999, 1999/2000, and 2000/2001 of vegetative buds of apple cultivars ‘Sampion’ and ‘Spartan’ after the first step of cryopreservation protocol at –30°C (A), and after the second step, reaching the LN temperature (B). ND variant was cryopreserved immediately after sampling from the orchard. D variant was cryopreserved after frost dehydration of at least 1 week at –4°C. Survival was tested by examination of oxidative browning of tissues on the longitudinal cut of the bud. Water content was measured immediately before cryopreservation procedure. Bars indicate SD (p < 0.05).
© Copyright Policy
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC4561819&req=5

Figure 7: Average survival from three seasons of 1998/1999, 1999/2000, and 2000/2001 of vegetative buds of apple cultivars ‘Sampion’ and ‘Spartan’ after the first step of cryopreservation protocol at –30°C (A), and after the second step, reaching the LN temperature (B). ND variant was cryopreserved immediately after sampling from the orchard. D variant was cryopreserved after frost dehydration of at least 1 week at –4°C. Survival was tested by examination of oxidative browning of tissues on the longitudinal cut of the bud. Water content was measured immediately before cryopreservation procedure. Bars indicate SD (p < 0.05).
Mentions: After the first step of the cryopreservation (to –30°C) both cultivars had the highest survival in December contrary to the lowest bud survival in September (Figure 7A). The differences in survival were found either between individual apple cultivars or between ND and D variants in each cultivar. Dehydrated buds of both cultivars showed a higher frost survival after –30°C, after the first step of cryopreservation protocol. It was mainly in October and November, when the buds were not cold acclimated yet. The used dehydration procedure enhanced cold acclimation. The maximal survival after the first cooling to –30°C was prerequisite for the following second step of the cryopreservation protocol. Cold hardiness, acquired either early in the dormant season during good acclimation conditions (Stushnoff, 1991) or later in winter after reacclimation at artificial storage at –4°C (Forsline et al., 1998), is considered a key step for successful cryopreservation. This is in consistence with our results (Figure 7). Aronen and Ryynanen (2014) found in hybrid aspen that the time schedule for cryopreservation of dormant buds could be extended from mid-winter to late autumn without compromising the recovery of the cryostored material. From October to February, on average, over 75% of their cryopreserved buds could be regenerated by micropropagation.

Bottom Line: The cryosurvival of vegetative apple buds of both cultivars correlated with their cold hardening without direct regard to their particular phase of dormancy.Both cultivars had the highest cryosurvival in December and January.The presented data were compared with our previous results from a dormancy study of in vitro apple culture.

View Article: PubMed Central - PubMed

Affiliation: Plant Physiology and Cryobiology Laboratory, Crop Research Institute Prague, Czech Republic.

ABSTRACT
Increasing interest in cryopreservation of dormant buds reveals the need for better understanding of the role of dormancy in cryotolerance. Dormancy stage and low-temperature survival of vegetative apple buds (Malus domestica Borkh.), cultivars 'Sampion' and 'Spartan', collected from orchard were evaluated during three seasons contrasting in temperature and precipitation throughout the arrested plant growth period. During each season, the cultivars differed either in the onset of the endodormancy or in the length of the endodormant period. A simple relation between endodormancy of the buds and their water content was not detected. The cryosurvival of vegetative apple buds of both cultivars correlated with their cold hardening without direct regard to their particular phase of dormancy. The period of the highest bud cryotolerance after low-temperature exposure overlapped with the endodormant period in some evaluated seasons. Both cultivars had the highest cryosurvival in December and January. The presented data were compared with our previous results from a dormancy study of in vitro apple culture. Endodormancy coincided with the period of successful cryosurvival of apple buds after liquid nitrogen exposure, but as such, it was not decisive for their survival and did not limit their successful cryopreservation.

No MeSH data available.


Related in: MedlinePlus