scholarly journals Changes in cold hardiness of silver fir and larch bare-rooted seedlings during autumn and spring

2012 ◽  
Vol 50 (No. 5) ◽  
pp. 237-242 ◽  
Author(s):  
M. Sarvaš

The objective of this study was to obtain information about changes in cold hardiness of larch and silver fir seedlings during autumn and spring by help of measurements of electrolyte leakage from shoots (SEL) and root system (REL). The values of electrolyte leakage from the untreated (control) root system of silver fir decreased during autumn (from 28% on September 25 to 24% on November 27). Minimum values were reached on March 26. A decrease in electrolyte leakage was found for silver fir shoots (SEL) (the maximum was detected on October 2 – 12% and minimum on November 27 – 7%). Contrary to REL, SEL increased in March. The rate of electrolyte leakage from treated (after artificial frost) roots and shoots decreased during autumn (REL and SEL minimum on November 27). The change in the rate of electrolyte leakage from untreated larch roots was similar to that from silver fir roots during autumn. The values continually decreased from 26% (on September 25) to 12% (on November 27). The course of electrolyte leakage from the treated root system was similar for both species. The differences between electrolyte leakage from larch shoots (treated und untreated ones) were statistically significant, but without any clear tendency during autumn.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Tina Unuk Nahberger ◽  
Gian Maria Niccolò Benucci ◽  
Hojka Kraigher ◽  
Tine Grebenc

AbstractSpecies of the genus Tuber have gained a lot of attention in recent decades due to their aromatic hypogenous fruitbodies, which can bring high prices on the market. The tendency in truffle production is to infect oak, hazel, beech, etc. in greenhouse conditions. We aimed to show whether silver fir (Abies alba Mill.) can be an appropriate host partner for commercial mycorrhization with truffles, and how earthworms in the inoculation substrate would affect the mycorrhization dynamics. Silver fir seedlings inoculated with Tuber. aestivum were analyzed for root system parameters and mycorrhization, how earthworms affect the bare root system, and if mycorrhization parameters change when earthworms are added to the inoculation substrate. Seedlings were analyzed 6 and 12 months after spore inoculation. Mycorrhization with or without earthworms revealed contrasting effects on fine root biomass and morphology of silver fir seedlings. Only a few of the assessed fine root parameters showed statistically significant response, namely higher fine root biomass and fine root tip density in inoculated seedlings without earthworms 6 months after inoculation, lower fine root tip density when earthworms were added, the specific root tip density increased in inoculated seedlings without earthworms 12 months after inoculation, and general negative effect of earthworm on branching density. Silver fir was confirmed as a suitable host partner for commercial mycorrhization with truffles, with 6% and 35% mycorrhization 6 months after inoculation and between 36% and 55% mycorrhization 12 months after inoculation. The effect of earthworms on mycorrhization of silver fir with Tuber aestivum was positive only after 6 months of mycorrhization, while this effect disappeared and turned insignificantly negative after 12 months due to the secondary effect of grazing on ectomycorrhizal root tips.


2008 ◽  
Vol 38 (6) ◽  
pp. 1526-1535 ◽  
Author(s):  
Douglass F. Jacobs ◽  
Anthony S. Davis ◽  
Barrett C. Wilson ◽  
R. Kasten Dumroese ◽  
Rosa C. Goodman ◽  
...  

We tested effects of shortened day length during nursery culture on Douglas-fir ( Pseudotsuga menziesii var. menziesii (Mirb.) Franco) seedling development at dormancy release. Seedlings from a 42°N source were grown either under ambient photoperiods (long-day (LD)) or with a 28 day period of 9 h light : 15 h dark photoperiods (short-day (SD)). Seedlings were periodically removed from freezer storage from January to May. Sensitivity of plant tissues to cold temperatures was investigated via electrolyte leakage at nine test temperatures ranging from 2 to –40 °C. New root growth was assessed with rhizosphere temperatures of 10, 15, 20, and 25 °C. From 2 to –13 °C, there was no difference between treatments in cold hardiness. However, at or below –18 °C, LD seedlings exhibited higher indices of damage than SD seedlings. The LT50 (temperature at which 50% cell electrolyte leakage occurred) was consistently lower for SD than LD seedlings. Rhizosphere temperature differentially influenced new root proliferation: LD seedlings had greater new root production than SD seedlings at 20 °C, whereas the opposite response was detected at 10 °C. Our results confirm photoperiod sensitivity of Douglas-fir sources from relatively low (i.e., <45°N) latitudes. Increased spring cold hardiness and greater rooting at lower rhizosphere temperatures may improve field performance potential of SD-treated seedlings.


HortScience ◽  
1992 ◽  
Vol 27 (6) ◽  
pp. 655f-655
Author(s):  
Frank B. Matta ◽  
Patricia Quesada

Differential thermal analysis, electrolyte leakage, tetrazolium stain test, and the “feeder plate” tissue culture regeneration technique were used to determine cold hardiness of passion fruit and maypop. The “feeder plate” technique showed that yellow passion fruit did not regenerate at 0C, -3C, and -6C while purple passion fruit showed callus formation at all temperatures. The remaining tests gave similar lethal temperatures for the two species. Lethal temperatures were -9C to -10C, -10C to -I2C, and -11C to -13C for yellow and purple passion fruit and maypop, respectively.


1991 ◽  
Vol 21 (6) ◽  
pp. 890-901 ◽  
Author(s):  
H. M. McKay ◽  
W. L. Mason

Two-year-old transplants and undercuts of Piceasitchensis (Bong.) Carr. and Pseudotsugamenziesii (Mirb.) Franco were cold-stored (1 °C) for 1 to 7 months ending in April 1989. Their physiological arid morphological condition at lifting and after storage was assessed and related to survival and height increment on a reafforestation site after one growing season. Physiological assessments made between October and April at lifting were root growth potential, tolerance of fine roots to chronic cold, shoot and root mitotic index, root elongation, and electrolyte leakage from the shoot and roots. Shoot cold hardiness was assessed between October and mid-December. The seasonal changes in these parameters and the effect of species and undercutting treatments are described. At lifting, root growth potential identified (i) differences due to species and undercutting treatments and (ii) the earliest possible safe lifting dates of P. menziesii but not of P. sitchensis. After cold storage, plant vigour was assessed by root growth potential and shoot and root membrane integrity. Membrane integrity of the fine roots was a very good indicator of survival. There was a highly significant, negative correlation between the rate of electrolyte leakage, indicating membrane damage, and survival (p ≤ 0.001, r = −0.90).


1992 ◽  
Vol 22 (7) ◽  
pp. 932-938 ◽  
Author(s):  
Mark D. Coleman ◽  
Thomas M. Hinckley ◽  
Geoffrey McNaughton ◽  
Barbara A. Smit

Root and needle cold hardiness were compared in seedlings of subalpine conifers to determine if differences existed among species originating from either cold continental climates or mild maritime climates. Abiesamabilis (Dougl.) Carr. and Tsugamertensiana (Bong.) Carr. are exclusively distributed in maritime environments, while Abieslasiocarpa (Hook.) Nutt. and Pinuscontorta Dougl. are more generally distributed in both continental and maritime environments. Because of the differing winter soil conditions of these two climatic types, special emphasis was placed on root cold hardiness. Cold hardiness for root samples, as measured by a decrease in the electrolyte leakage, was much greater for A. amabilis and A. lasiocarpa than for P. contorta and T. mertensiana (−11.4, −11.5, −7.5, and −7.5 °C, respectively). Thus, subalpine conifer species distribution was not found to be influenced by root cold hardiness. Root cold hardiness of field-grown seedlings paralleled changes in soil temperature through February. Under constant temperature conditions (3 °C) the maximum cold hardiness achieved in 6 weeks was not subsequently maintained in A. amabilis and A. lasiocarpa. Injury in unhardened roots was coincident with bulk freezing, whereas hardened roots were able to tolerate bulk freezing. Needles had more than three times the level of cold hardiness of roots when measured in December, All species except P. contorta reached needle cold hardiness levels below −40 °C.


2017 ◽  
pp. 399-404 ◽  
Author(s):  
S.J. Kim ◽  
J.C. Nam ◽  
S.M. Jung ◽  
Y.Y. Hur ◽  
H.I. Kim ◽  
...  

2002 ◽  
Vol 80 (4) ◽  
pp. 390-398 ◽  
Author(s):  
X B Zhu ◽  
R M Cox ◽  
C -PA Bourque ◽  
P A Arp

One-year-old, cold-hardened, container-grown yellow birch (Betula alleghaniensis Britt.) seedlings were exposed to cold treatments after being pretreated with a simulated winter thaw. Freezing injury to roots and shoots was assessed by relative electrolyte leakage and triphenyltetrazolium chloride reduction. Growth characteristics were also determined after 60 days under greenhouse conditions. Relative electrolyte leakage and triphenyltetrazolium chloride reduction measurements showed that roots became increasingly damaged with decreasing cold-treatment temperatures. However, plants pretreated with thaws showed significantly lower stem increment, shoot length, and leaf area in response to the cold temperatures than did the unthawed plants. Variation in these growth parameters was also significantly correlated with both root and shoot freezing injury parameters. Cold hardiness under different thaw pretreatments was assessed using the highest freezing temperature that caused significant injury, referred to as the critical temperature. For seedlings without the thaw pretreatment, shoot and root critical temperatures were estimated as –52.5 and 23.8°C, respectively. Following 12 days of thaw, these temperatures increased to –24.08°C for shoots and –13°C for roots. Twelve days of thaw, or growing degree-day (>4°C) accumulations greater than 66 during a thaw, could sufficiently deharden roots and shoots such that they would be susceptible to freezing damage at ambient temperatures commonly encountered in the Canadian Maritimes. We also observed that root pressure declined significantly with increasing root freezing injury. Sufficient root pressure is required for springtime refilling of xylem embolisms caused by winter cavitation of the vessels in this species. Weak root pressure caused by freezing injury would represent a risk of shoot dieback and tree decline due to the remaining embolisms reducing water flow to the developing foliage. The rapid reduction of shoot cold hardiness may also indicate the threat of late-spring frosts to this species. These induced changes are especially important under climate change scenarios that suggest increases in winter temperatures and changes in seasonality in eastern Canada.Key words: climate change, cold hardiness, electrolyte leakage, growth, root pressure, TTC reduction.


1985 ◽  
Vol 15 (4) ◽  
pp. 669-672 ◽  
Author(s):  
Robert O. Teskey ◽  
Charles C. Grier ◽  
Thomas M. Hinckley

The water inflow capacity of the root systems of several 15- to 18-year-old Pacific silver fir (Abiesamabilis (Dougl.) Forbes) trees was investigated under field conditions. Severance of as much as one-third of the roots had no effect on xylem pressure potential, leaf conductance, or transpiration throughout the day following this treatment. Severance of more than half of the root system caused a decline in xylem pressure potential and partial stomatal closure. Measurements from trees which had been completely severed from their roots indicated that stored water made only a small contribution to the supply of water to the foliage of these trees. It was concluded that a balance did not exist between the capacity for water inflow and the rate of foliar water loss, at least in periods without drought. One advantage of excess absorptive capacity may be the ability to obtain adequate amounts of water from relatively small portions of the rooting zone.


2013 ◽  
Vol 56 (1-2) ◽  
pp. 117-125
Author(s):  
Beata Meszka ◽  
Anna Bielenin

Effect of autumn urea application on cold hardiness of apple trees was investigated at Experimental Orchard in Dąbrowice on four apple cultivars ('Szampioii'. ´Jonagold´, ´Elstar' and 'Spartan´) of different sensitivity to low temperature injuries. During three-years experiment (2000-2002) no changes in frost resistance of apple trees after urea treatment in the end of October (during leaves fall) were noted. After the earlier application of urea, at middle of October. significantly more damages of annual shoots of cv. ´Jonagold' occurred only in the season 2001. These damages did not influence later growth of apple trees. Spring observations indicated that for all apple's cultivars setting of buds was better on treated with urea than on untreated ones. Electrolyte leakage determinations confirmed the field results that urea did not cause decrease in low temperature resistance of apple trees.


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