Supercooling ability of Rhododendron flower buds in relation to cooling rate and cold hardiness

1980 ◽  
Keyword(s):  
Cooling Rate ◽  
Cold Hardiness ◽  
Flower Buds

Supercooling ability of Rhododendron flower buds in relation to cooling rate and cold hardiness

1980 ◽  
Vol 21 (8) ◽  
pp. 1205-1216 ◽  
Author(s):  
Shosuke Kaku ◽  
Mari Iwaya ◽  
Masaaki Kunishige
Keyword(s):  
Cooling Rate ◽  
Cold Hardiness ◽  
Flower Buds

THE COLD HARDINESS OF FLOWER BUDS IN TWO APRICOT CULTIVARS

2006 ◽  
pp. 141-146 ◽  
Author(s):  
S. Bartolini ◽  
G. Zanol ◽  
R. Viti
Keyword(s):  
Cold Hardiness ◽  
Flower Buds

scholarly journals Cooling and Warming Effects on Cold Hardiness Estimations of Three Woody Ornamental Taxa

HortScience ◽  
1992 ◽  
Vol 27 (12) ◽  
pp. 1308-1309 ◽  
Author(s):  
C.L. Haynes ◽  
O.M. Lindstrom ◽  
M.A. Dirr
Keyword(s):  
Cooling Rate ◽  
Cold Hardiness ◽  
Cooling Rates ◽  
Woody Ornamental

Cooling treatments of 2, 4, and 6C/hour or warming at 25, 4, or 0C influenced the cold hardiness estimates of x Cupressocyparis leylandii (A.B. Jacks. and Dallim.) Dallim. and A.B. Jacks. (Leyland cypress), Lagerstroemia indica L. (crape myrtle), and Photinia ×fraseri Dress `Birmingham' (redtip photinia) at four times during the year. New growth from all taxa, especially spring growth, was injured or killed at higher temperatures by the fastest cooling rate and/or by warming at 25C. Cold hardiness of Leyland cypress was unaffected by the cooling and warming treatments. Crape myrtle had a significantly higher lowest survival temperature (LST) when warmed at 25C than at 4 or 0C. Photinia leaves and stems cooled at 6C/hour or warmed at 25C generally resulted in a higher LST than those cooled more slowly or warmed at lower temperatures. Cooling rates of 14C/hour and warming at 0 to 4C should be used in freeze tests with Leyland cypress and crape myrtle. For leaves and stems of photinia, 2C/hour cooling and warming at 0 to 4C should be used.

scholarly journals Dormancy, Cold Hardiness, Dehardening, and Rehardening in Selected Red Raspberry Cultivars

1999 ◽  
Vol 124 (4) ◽  
pp. 341-346 ◽  
Author(s):  
Pauliina Palonen ◽  
Leena Lindén
Keyword(s):  
Cold Hardiness ◽  
The State ◽  
Rubus Idaeus ◽  
Cultivar Differences ◽  
Dormancy Release ◽  
Red Raspberry ◽  
Flower Buds

Canes and flower buds of selected red raspberry cultivars (Rubus idaeus L. `Maurin Makea', `Muskoka', and `Ottawa') were sampled from a field (latitude, 61 °20'N; longitude, 24 °13'E) at 1-month intervals during Winter 1996-97 to study the interaction of dormancy and cold hardiness, hardiness retention, and rehardening capacity. One set of canes was subjected to dehardening (3 days) and two sets to dehardening + rehardening (3 and 7 days) treatments before cold hardiness determination. Maximum midwinter hardiness occurred in January, after breaking of endodormancy. Cold hardiness of canes and buds reached -28.6 to -37.2 °C and -24.2 to -31.6 °C, respectively. Throughout the winter, raspberry canes were hardier than buds. Endodormancy had a greater influence on dehardening and rehardening in buds than in canes, and cultivars differed in their response. Dehardening of `Maurin Makea' canes and buds, and `Muskoka' buds was slightly enhanced by breaking of dormancy, whereas dehardening in `Ottawa' was not affected by dormancy. Raspberry canes and buds could reharden even after dormancy release. Rehardening capacity was affected by the state of dormancy only in `Maurin Makea' buds. Changes in dormancy status failed to explain cultivar differences regarding dehardening and the capacity to reharden suggesting other factors may be involved.

scholarly journals Preferential freezing avoidance localized in anthers and embryo sacs in wintering Daphne kamtschatica var. jezoensis flower buds visualized by MRI

2021 ◽  
Author(s):  
Masaya Ishikawa ◽  
Hiroyuki Ide ◽  
Tetsuya Tsujii ◽  
Timothy Stait-Gardner ◽  
Hikaru Kubo ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Cold Hardiness ◽  
Ice Nucleation ◽  
Ice Formation ◽  
Resonance Imaging ◽  
Flower Buds ◽  
Male And Female ◽  
Nucleation Activity ◽  
Magnetic Resonance Imaging Mri ◽  
Ice Nucleation Activity

To explore diversity in cold hardiness mechanisms, high resolution magnetic resonance imaging (MRI) was used to visualize freezing behaviors in wintering flower buds of Daphne kamtschatica var. jezoensis, which have no bud scales surrounding well-developed florets. MRI images showed that anthers remained stably supercooled to -14 ∼ -21°C or lower whilst most other tissues froze by -7°C. Freezing of some anthers detected in MRI images at ∼ -21°C corresponded with numerous low temperature exotherms and also with the “all-or-nothing” type of anther injuries. In ovules/pistils, only embryo sacs remained supercooled at -7°C or lower, but slowly dehydrated during further cooling. Cryomicroscopic observation revealed ice formation in the cavities of calyx tubes and pistils but detected no ice in embryo sacs or in anthers. The distribution of ice nucleation activity in floral tissues corroborated the tissue freezing behaviors. Filaments likely work as the ice blocking barrier that prevents ice intrusion from extracellularly frozen calyx tubes to connecting unfrozen anthers. Unique freezing behaviors were demonstrated in Daphne flower buds: preferential freezing avoidance in male and female gametophytes and their surrounding tissues (by stable supercooling in anthers and by supercooling with slow dehydration in embryo sacs) whilst the remaining tissues tolerate extracellular freezing.

A 15-year long assessment of cold hardiness of apricot flower buds and flowers during the blooming period

2021 ◽  
Vol 290 ◽  
pp. 110520
Author(s):  
László Szalay ◽  
József Bakos ◽  
Ágnes Tósaki ◽  
Belay Teweldemedhin Keleta ◽  
Veronika Froemel-Hajnal ◽  
...  
Keyword(s):  
Cold Hardiness ◽  
Flower Buds

Freezing media affect cooling rate and regrowth of KSC 28 apple rootstock

1997 ◽  
Vol 77 (3) ◽  
pp. 469-471 ◽  
Author(s):  
Jean-Pierre Privé ◽  
Charlie Embree
Keyword(s):  
Cooling Rate ◽  
Cold Hardiness ◽  
Temperature Gradients ◽  
Controlled Environment ◽  
Uniform Temperature ◽  
Apple Rootstock ◽  
Cooling Rates ◽  
Root Regrowth ◽  
Plastic Bag ◽  
Environment Chamber

To examine the effect that media have on cooling rates and subsequent plant regrowth, bare-rooted Kentville Select Clone 28 (KSC28) apple (Malus domestica Borkh.) roots were placed in various media (water, sawdust, soilless mixture and plastic bag) and set in a controlled environment chamber preset to −12 °C. Cooling rates differed between media with water and the plastic bag requiring the most and the least time to reach −12 °C, respectively. Shoot and root regrowth were similar for all treatments except water, which was significantly reduced. The plastic bag treatment provided the most uniform temperature gradients throughout the root system and the fastest cooling rate, was the easiest to handle, and allowed good regrowth. Key words: KSC28 apple rootstock, sawdust, soilless mix, cold hardiness testing

Sign in / Sign up

Export Citation Format

Share Document