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1
Graczyk, Dariusz, et Małgorzata Szwed. « Changes in the Occurrence of Late Spring Frost in Poland ». Agronomy 10, no 11 (22 novembre 2020) : 1835. http://dx.doi.org/10.3390/agronomy10111835.
Texte intégralRésumé :
Trends in the appearance of the last spring frost for three thresholds of minimum daily air temperature at the height of 2 m and near the ground were examined for six meteorological stations located in two agricultural regions in Poland. For most time series, the last spring frost, calculated as a consecutive day of the year, showed a statistically significant trend indicating its earlier appearance from 1.6 to about 3.5 days per decade. The date of the last spring frost was also calculated in relation to the ongoing growing season. In this case, few statistically significant changes in the dates of the last frosts were found. The probability of the last spring frost on a specific day of the calendar year and the day of the growing season was also examined for two periods: 1961–1990 and 1991–2020. For low probability levels corresponding to the early dates of the last spring frost, the last frost usually occurred much earlier (6–14 days) in 1991–2020. With the probability levels of 80–90% describing the late occurrence of the last frost with a frequency of once every 5–10 years, at some stations, the last spring frosts occurred at a similar time for both periods.
2
Nienstaedt, Hans. « Inheritance and correlations of frost injury, growth, flowering, and cone characteristics in white spruce, Piceaglauca (Moench) Voss ». Canadian Journal of Forest Research 15, no 3 (1 juin 1985) : 498–504. http://dx.doi.org/10.1139/x85-082.
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White spruce progenies from the Lake States (61) and from the Ottawa River Valley, Ontario (31), were tested in north-central Wisconsin. Transplants were raised in nurseries in Wisconsin and Ontario and planted in 1969 in an open field after thorough weed control. Observations in the Wisconsin nursery and in the field between 1971 and 1979 are reported. They included heights, frost damage, spring vegetative growth phenology, strobili production, and three cone characteristics. The discussion concentrates on the relationships between heights and the other measured characteristics. Frost damage proved difficult to assess. In the year of frost, damage is severe, a 50% growth reduction, and the fastest growing trees are most severely damaged. However, in environments with only occasional late spring frosts, permanent damage is negligible. Spring growth initiation was not correlated significantly with total height growth or frost damage. Breeding of late-flushing genotypes that can avoid frost damage is questionable in spite of the high heritability for flushing. Female strobili production was substantial at age 10 years, male production was not. Even so, generation turnovers of 10–15 years may be possible. The impact of fecundity on growth potential is discussed as it relates to multigeneration breeding.
3
Tadić, Vjekoslav, Kosta Gligorević, Zoran Mileusnić, Rajko Miodragović, Marko Hajmiler et Dorijan Radočaj. « Agricultural Engineering Technologies in the Control of Frost Damage in Permanent Plantations ». AgriEngineering 5, no 4 (6 novembre 2023) : 2079–111. http://dx.doi.org/10.3390/agriengineering5040128.
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The occurrence of late spring frosts due to climate change causes great damage to plantation production worldwide. The main objective of the paper is to provide a comprehensive overview of the problem and to outline effective protective measures against late spring frosts. The nature of frost depends on regional, altitudinal, and geographic differences, but they all share a common problem: they remove heat, resulting in the freezing of new plant growth and flowers. Tissue freezing is affected by critical temperatures and the frost type, intensity, and duration. Protection against late spring frosts can be broadly divided into three categories: active, passive, and chemical measures. In the field of agricultural engineering, various techniques have been thoroughly researched, and their effectiveness has been confirmed by research. These include various sprinkler systems, different heating devices, and large-diameter fans. Conclusive findings are being made on the performance of these systems in sub-zero temperatures and their cost-effectiveness. Climate change increases the importance of protecting permanent crops from late spring frosts and requires advances in agricultural technology to meet changing production demands and challenges.
4
Cutforth, Herb, EG (Ted) O’Brien, Jason Tuchelt et Rick Rickwood. « Long-term changes in the frost-free season on the Canadian prairies ». Canadian Journal of Plant Science 84, no 4 (1 octobre 2004) : 1085–91. http://dx.doi.org/10.4141/p03-169.
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The climate of the prairies has warmed over the past century, especially during late winter and early spring. Some regions of the prairies have warmed faster than others. Climate change has been documented to affect living systems in North America, such as promoting earlier phenological development and longer growing seasons. We examined weather records gathered at several long-term weather-recording sites across the agricultural regions of the Canadian prairies for evidence of trends in last spring frosts, first fall frosts, and frost-free durations. During the latter half of the 20th century, the trends were towards earlier last spring frost dates and towards longer frost-free seasons in the agricultural regions of the Canadian prairies. Across most of the prairies the trends towards later first fall frost dates were smaller and generally not significant. The largest changes have occurred in the central and northern agricultural regions of Alberta, whereas the least change occurred over much of southern Alberta and in southern Manitoba. Key words: Last spring and first fall frost dates, frost-free season, agroclimatic indices, climate change, Canadian prairies
5
Imfeld, Noemi, Koen Hufkens et Stefan Brönnimann. « Extreme springs in Switzerland since 1763 in climate and phenological indices ». Climate of the Past 20, no 3 (22 mars 2024) : 659–82. http://dx.doi.org/10.5194/cp-20-659-2024.
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Abstract. Historical sources report manifold on hazardous past climate and weather events that had considerable impacts on society. Studying changes in the occurrence or mechanisms behind such events is, however, hampered by a lack of spatially and temporally complete weather data. In particular, the spring season has received less attention in comparison to summer and winter but is nevertheless relevant, since weather conditions in spring can delay vegetation and create substantial damage due to late-frost events. For Switzerland, we created a daily high-resolution (1 × 1 km2) reconstruction of temperature and precipitation fields from 1763 to 1960 that forms, together with present-day meteorological fields, a 258-year-long gridded data set. With this data set, we study changes in long-term climate and historical weather events based on climate and phenological indices focusing on the spring season. Climate and phenological indices show few changes in the mean during the first 200 years compared to the most recent period from 1991 to 2020, where climate change signals clearly emerged in many indices. We evaluate the climate and phenological indices for three cases of extreme spring weather conditions: an unusually warm spring, two late-frost events, and three cold springs. Warm springs are much more frequent in the 21st century, but a very warm and early spring also occurred in 1862. Spring temperatures, however, do not agree on how anomalously warm the spring was when comparing the Swiss temperature reconstruction with reanalyses that extend back to 1868. The three springs of 1785, 1837, and 1853 were particularly cold, with historical sources reporting, for example, prolonged lake freezing and abundant snowfall. Whereas the springs of 1837 and 1853 were characterized by cold and wet conditions, in the spring of 1785 wet days were below average, and frost days reached an all-time maximum, in particular in the Swiss Plateau, indicating inversion conditions. Such conditions are in line with a high occurrence of northeasterly and high-pressure weather types and historical sources describing Bise conditions, a regional wind in the Alpine area related to inversions. Studying such historical events is valuable, since similar atmospheric conditions can lead to cold springs affecting vegetation growth and agricultural production.
6
Neuendorff, E. W., et K. D. Patten. « EFFECT OF HEDGING ON FROST TOLERANCE OF `DELITE' RABBITEYE BLUEBERRIES ». HortScience 25, no 9 (septembre 1990) : 1162d—1162. http://dx.doi.org/10.21273/hortsci.25.9.1162d.
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A late spring frost, -2°C on 10 Mar 1989, destroyed all blossoms on `Delite' rabbiteye blueberries. To determine the effect of hedging as a rejuvenation method, six-year-old `Delite' plants were pruned on 26 April 1989. All branches were removed at 46 cm from ground level. Unpruned control plants were approximately 184 cm tall. On 21 Mar 1990 a frost of -2°C occurred. Two days later bud damage was assessed on three wood types: spring-old (SO), spring growth on old, weak wood; spring-new (SN), spring growth on vigorous 1-year-old shoots; and fall (F), postharvest late summer/fall growth. Buds were identified as to their stage of development. Buds formed on both types of spring wood were further developed than those on fall wood. As flower stage advanced frost damage increased. Blossoms on fall growth were most frost tolerant and SN was more hardy than SO. Subsequent yields will be determined and reported.
7
Dolnicki, Adam, et Wojciech Kraj. « Dynamics of frost resistance in various provenances of Abies grandis Lindl. » Acta Societatis Botanicorum Poloniae 67, no 1 (2014) : 51–58. http://dx.doi.org/10.5586/asbp.1998.006.
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The frost resistance of one year old needles and shoots of <em>Abies grandis</em> (seven provenances) and <em>Abies alba</em> (one provenance) was determined using Dexter's method since early autumn till late spring (September-May). Material was collected from trees over ten year old, planted in Beskid Sądecki Range near Krynica, 800 m above sea level. In this study it was found, that in early autumn (September) <em>A. grandis</em> develops weaker frost hardiness than <em>Abies alba</em>. In the late autumn and in winter, provenances coming from region II (according to Müller), and especially provenance 12016, are equal in respect to frost hardiness of shoots and needles to <em>Abies alba</em>. Among the provenances from Müller's region I exceptional frost hardiness is displayed by provenance 12005, which is also characterized by fast growth. In spring, <em>Abies alba</em> flushes earlier than <em>A. grandis</em>, which makes it more susceptible to late frosts.
8
Čehulić, Ivica, Krunoslav Sever, Ida Katičić Bogdan, Anamarija Jazbec, Željko Škvorc et Saša Bogdan. « Drought Impact on Leaf Phenology and Spring Frost Susceptibility in a Quercus robur L. Provenance Trial ». Forests 10, no 1 (11 janvier 2019) : 50. http://dx.doi.org/10.3390/f10010050.
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Research highlights: The susceptibility of oaks to late spring and early autumn frosts is directly related to their leaf phenology. Drought may alter the leaf phenology and therefore frost tolerance of oaks. However, the effects of drought on oak leaf phenology and frost resistance have not been thoroughly studied. Background and objectives: One of the consequences of climate change is an increase in the frequency of dry episodes during the vegetation period. Pedunculate oak (Quercus robur L.) is an economically and ecologically important forest tree species that prefers humid habitats. Therefore, knowledge of the impact of drought on this species is of great importance for the adaptation of forestry strategies and practices to altered environmental conditions. The aim of this study was to determine the impact of drought on leaf phenology and spring frost susceptibility in nine provenances. Materials and methods: One-year-old saplings originating from nine European provenances were used in the trial. The saplings were exposed to experimental drought and then re-watered in two subsequent years. Spring and autumn leaf phenology were scored. The trial was impacted by a late spring frost in the third year, and the resulting leaf frost injury was scored. The effects of drought treatment on the phenology and frost susceptibility of plants from the provenances were analysed. Results: Leaf phenology of plants from most of the studied provenances was significantly influenced by the drought treatment (p < 0.001). Drought induced a carry-over effect on flushing phenology, which was observed as delayed bud burst (from 0.6 to 2.4 days) in the second year and as advanced bud burst (from 0.1 to 6.3 days) in the third year. Therefore, opposite shifts in flushing phenology may be induced as a result of differences in the time span when plants sense water deficits. In contrast to flushing, autumn leaf phenology was unambiguously delayed following the drought treatments for all studied provenances (from 2.1 to 25.8 days). Differences in late frost susceptibility were predominantly caused by among-provenance differences in flushing phenology. However, the drought treatment significantly increased frost susceptibility in the plants (the rate of frost-injured plants per provenance increased from 3% to 78%). This higher susceptibility to spring frost was most likely caused by the advanced flushing phenology that resulted from the drought treatment in the previous year.
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Zohner, Constantin M., Lidong Mo, Susanne S. Renner, Jens-Christian Svenning, Yann Vitasse, Blas M. Benito, Alejandro Ordonez et al. « Late-spring frost risk between 1959 and 2017 decreased in North America but increased in Europe and Asia ». Proceedings of the National Academy of Sciences 117, no 22 (11 mai 2020) : 12192–200. http://dx.doi.org/10.1073/pnas.1920816117.
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Late-spring frosts (LSFs) affect the performance of plants and animals across the world’s temperate and boreal zones, but despite their ecological and economic impact on agriculture and forestry, the geographic distribution and evolutionary impact of these frost events are poorly understood. Here, we analyze LSFs between 1959 and 2017 and the resistance strategies of Northern Hemisphere woody species to infer trees’ adaptations for minimizing frost damage to their leaves and to forecast forest vulnerability under the ongoing changes in frost frequencies. Trait values on leaf-out and leaf-freezing resistance come from up to 1,500 temperate and boreal woody species cultivated in common gardens. We find that areas in which LSFs are common, such as eastern North America, harbor tree species with cautious (late-leafing) leaf-out strategies. Areas in which LSFs used to be unlikely, such as broad-leaved forests and shrublands in Europe and Asia, instead harbor opportunistic tree species (quickly reacting to warming air temperatures). LSFs in the latter regions are currently increasing, and given species’ innate resistance strategies, we estimate that ∼35% of the European and ∼26% of the Asian temperate forest area, but only ∼10% of the North American, will experience increasing late-frost damage in the future. Our findings reveal region-specific changes in the spring-frost risk that can inform decision-making in land management, forestry, agriculture, and insurance policy.
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Memišević Hodžić, Mirzeta, Almedin Hebibović et Dalibor Ballian. « Phenological variability and resistance to late spring frost of common beech in the international provenance test in Bosnia and Herzegovina ». Acta Silvae et Ligni 126 (décembre 2021) : 11–21. http://dx.doi.org/10.20315/asetl.126.2.
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The research aimed to determine the start, end and duration of leafing phases, the degree of plant damage caused by late spring frost, and the retention of leaves in autumn. The research was conducted in the international common beech provenance test in Bosnia and Herzegovina. The test contains eight provenances from Bosnia and Herzegovina, four from Germany, three from Serbia, two each from Croatia, Romania and Switzerland, and one from Hungary. Leafing phenology, canopy damage caused by late spring frost, and leaf retention were assessed in 2019. Most provenances started opening buds on 17 April 2019. Complete canopy damage affected the highest percentage of plants in provenance BW Bad Wildbad, Germany (68 %), and the lowest in provenance Konjuh Kladanj, Bosnia and Herzegovina (3.2 %). Provenance Herzogenbuchsee from Switzerland had the highest percentage of winter leaf retention (37.5 % of plants). The results can be used in choosing provenances that are resistant to low temperatures in zones of late spring and early autumn frost.
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Josef, Gallo, Baláš Martin, Linda Rostislav et Kuneš Ivan. « Growth performance and resistance to ground late frosts of Fagus sylvatica L. plantation treated with a brassinosteroid compound ». Journal of Forest Science 63, No. 3 (28 mars 2017) : 117–25. http://dx.doi.org/10.17221/67/2016-jfs.
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We measured the initial growth performance of a young plantation of European beech treated with a brassinosteroid compound prior to planting and compared it with a control treatment: we assessed heights, root collar diameters and mortality rate during the period 2012–2015. The trees showed posterior damage by ground frost after a substantial late frost event on the night of 4–5 May 2014. Therefore, we evaluated the post-stress vitality of trees, subsequent height increment from spring to August, and the height range of the damage.<br />Mean height, root collar diameter, and mortality rate did not show any significantly better performance in the brassinosteroid treatment over the control treatment. Neither did the application treatment have a significant positive effect on the resistance of beech to late frosts. The severe frost damage was most intense at 30 cm above ground, and rapidly declined with increased height.
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Kianian, M. K. ,., et H. ,. Hajimohammadi. « STUDYING THE IMPACT OF EARLY AUTUMN AND LATE SPRING FROSTS ON AGRICULTURAL CROPS YIELD IN IRAN ». EPH - International Journal of Agriculture and Environmental Research 6, no 2 (27 décembre 2020) : 1–9. http://dx.doi.org/10.53555/eijaer.v5i1.53.
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To study early autumn and late spring frosts and its relation to the yield of agriculture crops in Semnan province we used statistics the least daily minimum temperature of 6 stations in the months of October and November and April during the period (1993-2014) as well as information on yield of agricultural crops from horticulture department of agriculture Organization. Using Pearson correlation coefficient between yield and frequency of early autumn and late spring frosts were studied and finally induced to study the frosts trends for each station. Early frosts of autumn in the province date from 20 October to 23 November and latest frosts ranged from 3 to 23 April and Biarjomand station experience earliest autumn and latest spring frosts. The Relationship between crop yields with frost Occurrence frequency shows that by increasing the number of days of early autumn frosts reduced wheat yield. This condition is for crops such as peas, walnuts and grapes, too. Amongst, the greatest impact is on the potato crop, which is closely related to the pattern of cultivation and harvest. On the other hand, it was found that late spring frosts in the province have the greatest impact on horticultural crops such as cherries, peaches, walnuts and grapes. As a result, early and late frosts changes in Semnan and Miami has increased, which in coming years will be also affected by this situation. Also, early frosts of autumn at harvest time and late spring frosts during flowering have many effects on crop yield.
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Wang, Xiaopei, Lingquan Meng et Hongxu Wei. « Biomass, carbohydrate, and leakage conductance in buds of six ornamental tree species subjected to a “false spring” in Northeast China ». Annals of Forest Research 65, no 2 (31 décembre 2022) : 15–30. http://dx.doi.org/10.15287/afr.2022.2241.
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Information is highly scarce about the possible effect of a late spring frost on physiological response of buds in ornamental trees. In this study, spring temperature of Changchun at Northeast China was recorded to identify the characteristics of a false spring by detecting extraordinary warming and sudden freeze in early April of 2017. Buds of six local ornamental tree species were investigated for their dynamics in biomass, non-structural carbohydrates, frost resistance on days of 7, 14, 21, and 28 April 2017. According to a comparison with spring temperature records historically from 2007 to 2016, a false spring was determined. Black pine (Pinus tabuliformis var. mukdensis) had greater bud biomass than apricot (Prunus sibirica L.). Peach (Prunus persica L. var. persica f. rubro-plena Schneid.) reserved greater non-structural carbohydrate content in post-chilling buds than black pine, and apricot and willow (Salix babylonica L.) had greater soluble sugars and starch contents in buds, respectively. Cumulative number of days with temperature below 12°C had a negative relationship with relative conductance in sorbus (Sorbus pohuashanensis [Hance] Hedl.). Chokecherry (Padus virginiana ‘Canada Red’) had greatest bud starch content on 21 April. Overall, a late spring frost imposed interruption on carbohydrate metabolism rather than direct damage on buds of ornamental trees before late April. Advanced warming induced more pronounced negative impact of a false spring than the sudden decline of minimum temperature.
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Vander Mijnsbrugge, Kristine, Jessa May Malanguis, Stefaan Moreels, Amy Lauwers, Arno Thomaes, Luc De Keersmaeker et Kris Vandekerkhove. « Growth Recovery and Phenological Responses of Juvenile Beech (Fagus sylvatica L.) Exposed to Spring Warming and Late Spring Frost ». Forests 12, no 11 (20 novembre 2021) : 1604. http://dx.doi.org/10.3390/f12111604.
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Global change increases the risk of extreme climatic events. The impact of extreme temperature may depend on the tree species and also on the provenance. Ten provenances of Fagus sylvatica L. were grown in a common garden environment in Belgium and subjected to different temperature treatments. Half of the one year old seedlings were submitted to a high thermal stress in the spring of the first year, and all plants were exposed to a late spring frost in the second year. The high-temperature treated plants displayed reduced growth in the first year, which was fully compensated (recovery with exact compensation) in the second year for radial growth and in the third year for height growth. Frost in the spring of the second year damaged part of the saplings and reduced their growth. The frost damaged plants regained the pre-stress growth rate one year later (recovery without compensation). The high temperature treatment in the first year and the frost damage in the second year clearly influenced the phenological responses in the year of the event and in the succeeding year. Little population differentiation was observed among the provenances for growth and for phenological responses. Yet, a southern provenance, a non-autochthonous provenance (original German provenance that was planted in Belgium about a century ago) and a more continental provenance flushed earlier than the local Atlantic provenances in the year of the frost event, resulting in more frost damage. Some caution should therefore be taken when translocating provenances as an anticipation of the predicted climate warming.
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Kar, Suraj, Ricky W. Clark, Ian T. Ivey, Joseph B. DeShields, Jeremy Cusimano et Alexander D. Levin. « Post-Frost Pruning Does Not Impact Vine Yield and Berry Composition in Young Grapevines ». Horticulturae 10, no 5 (14 mai 2024) : 505. http://dx.doi.org/10.3390/horticulturae10050505.
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Spring frost is a perennial and widespread problem across many cool climatic and high-elevation winegrowing regions of the world. Vitis vinifera L. cv. Pinot noir is an early budding cultivar; thus, it is particularly susceptible to late-spring frost damage. In late April 2022, an advective frost event occurred throughout Western Oregon winegrowing regions and subsequently damaged a substantial number of commercial vineyards. Growers often are unsure of how to manage grapevines after a frost event. Limited research has shown little-to-no effect of pruning vs. non-pruning strategies on vine yield and productivity. In addition, pruning a frost-affected vineyard incurs additional labor costs that may offset the cost–benefit balance for the grower. Therefore, in this experiment, the effect of two different post-frost pruning treatments (cane pruning and spur pruning) on vine yield, berry composition, and vine vegetative growth were tested. No effect of post-frost pruning treatments on vine yield, berry composition, and vine vegetative characteristics was observed. Cluster numbers, cluster weights, and berries per cluster only differed between cane- vs. spur-pruned vines. Therefore, leaving frost-affected vines alone and a scaled-back vineyard management practice could be practical for economic reasons.
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Neuendorff, E. W., et K. P. Patten. « SEASONAL WOOD DEVELOPMENT EFFECTS ON FROST TOLERANCE AND FRUIT MATURITY OF RABBITEYE BLUEBERRIES ». HortScience 25, no 8 (août 1990) : 863g—863. http://dx.doi.org/10.21273/hortsci.25.8.863g.
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Rabbiteye blueberry flower buds are initiated and differentiated on three distinct wood types - spring growth on old weak growth, spring growth on vigorous 1-year-old shoots, or postharvest late summer/fall growth. Flower buds on spring growth are usually formed and visible by July, while buds formed on postharvest growth flushes appear in late summer and early fall. To evaluate the influence of wood type on cold damage, shoots of `Tifblue' and `Delite' were tagged by season of growth. Following a -10°C freeze in Feb. flower buds on shoots from each growth flush were examined for dead ovaries. Flower buds surviving the freeze were evaluated following a -2° late frost in Mar. Influence of wood type on floral bud and fruit development was determined. All fruit were removed from 5 shoots of each wood type on 2 harvest dates corresponding to early and midseason harvests. Floral buds formed on fall growth were more freeze and frost tolerant than those initiated on spring growth at similar stages of bud development. `Tifblue' was more cold tolerant than `Delite'. Floral buds formed on both spring wood types were earlier to develop than buds formed on fall wood. There were no differences in ripening patterns and quality of fruit removed from spring - new and fall wood. Fruit formed on spring - old wood were later maturing and smaller sized for both harvests than spring-new or fall wood. Postharvest pruning to encourage fall growth may be a cultural means of frost avoidance.
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Imani, A., A. Mousavi, S. Biat, M. Rasouli, R. Tavakoli et S. Piri. « GENETIC DIVERSITY FOR LATE FROST SPRING RESISTANCE IN ALMOND ». Acta Horticulturae, no 912 (novembre 2011) : 371–75. http://dx.doi.org/10.17660/actahortic.2011.912.54.
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Velisevich, Svetlana, et Alexander Popov. « Climate warming disturbances periodicity of Siberian stone pine seed production (Pinus sibirica Du Tour) ». BIO Web of Conferences 130 (2024) : 01018. http://dx.doi.org/10.1051/bioconf/202413001018.
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Siberian stone pine is one of the main edificator plants of taiga forests of Western Siberia. Sustainable functioning of forest ecosystems depends on its successful cone crops, as its seeds are the basis for the diet of many forest animals. A cone crop in this species is characterized by pronounced interannual variability, manifested in the formation of high seed yields once in 3-4 years. However, in the last 20 years, high yields have been rare, replaced by years with average and low yields. To establish the reasons for these changes, the dynamics of seeding in the period from 1990 to 2023 and weather conditions in spring in the pollination year during the same period were analyzed. It was found that the number of mature cones in the crown largely depended on spring weather in the year of pollination and was negatively correlated with the sum of active temperatures above +5°C accumulated before the late spring frost. If frost occurred at SAT above 300°C, the following year’s crop was minimized. Analysis of weather conditions showed that, on average, there is a tendency to shift the dates of the last frosts to later dates, and even a short-term decrease in temperature to -1 °C leads to complete death of the future crop of cones. Despite the growth of heat availability in the spring period due to active temperature increase in April, the expected shift of frosts to earlier dates is not observed in the south of Western Siberia. For Siberian stone pine, such situation is fraught with strengthening of negative trend in seeding dynamics. It is supposed that at further climate warming the beginning of spring development of reproductive structures will occur at earlier dates, so reproductive structures will be more damaged by late spring frosts, since the latter remain within the same time frames.
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Korzin, Vadim, Valentina Gorina et Nikita Saplev. « The effect of weather conditions in southern Russia on the frost resistance of apricot generative buds ». Horticultural Science 48, No. 4 (22 décembre 2021) : 158–65. http://dx.doi.org/10.17221/73/2020-hortsci.
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One of the reasons limiting the apricot expansion in the world is the short period of winter dormancy in the plants and the rapid development of generative buds in the spring. Apricot flower buds often die even after small spring return frosts that limit the commercial culture of this fruit crop. The aim of this investigation was to study collection-breeding plantations and select frost-resistant genotypes that have promise for commercial and breeding use. To solve this problem, the frost resistance of generative buds in 50 apricot cultivars and the breeding forms of various origins were studied by freezing treatments of the branches in a climatic chamber. The Czech cultivar ‘Leala’ was selected due to its best frost resistance. In late winter 2020–2021, six cultivars and breeding forms, which kept 41.8 to 65.9% of the generative buds alive, were identified. These genotypes are characterised by a slow development that prevents any negative freezing temperature effects. Thus, the results of the study confirmed the dependence of the adaptation mechanisms in apricot plants on the rates of their morphogenesis and abiotic factor pressures.
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Leolini, L., M. Moriondo, G. Fila, S. Costafreda-Aumedes, R. Ferrise et M. Bindi. « Late spring frost impacts on future grapevine distribution in Europe ». Field Crops Research 222 (juin 2018) : 197–208. http://dx.doi.org/10.1016/j.fcr.2017.11.018.
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Cutforth, H. W., B. G. McConkey, R. J. Woodvine, D. G. Smith, P. G. Jefferson et O. O. Akinremi. « Climate change in the semiarid prairie of southwestern Saskatchewan : Late winter–early spring ». Canadian Journal of Plant Science 79, no 3 (1 juillet 1999) : 343–50. http://dx.doi.org/10.4141/p98-137.
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Long-term weather and hydrological data were analyzed to study climate change during late winter–early spring within an approximately 15 000 km2 area in the semiarid prairie near Swift Current, Saskatchewan. The climate has changed over the past 50 yr. Winter and spring maximum and minimum temperatures have warmed, snowfall amounts have decreased, and spring runoff has started earlier now than during past years. The percentage of precipitation as snow has decreased as temperatures have warmed. As well, even though temperatures have warmed, the date of the last spring frost has not gotten earlier with time. Key words: Climate change, semiarid prairie, winter and spring, temperature, snow, spring runoff
22
Poling, E. B., H. Pat Fuller et K. B. Perry. « Frost/Freeze Protection of Strawberries Grown on Black Plastic Mulch ». HortScience 26, no 1 (janvier 1991) : 15–17. http://dx.doi.org/10.21273/hortsci.26.1.15.
Texte intégralRésumé :
Floating rowcovers composed of extruded polypropylene, spunbonded polypropylene, and polyester were used in 1987-88 in eastern North Carolina for cold protection of strawberries (Fragaria × ananassa Duch.) growing in annual hill culture on black plastic mulch. Treatments consisted of floating rowcovers in either winter, spring, or both with and without overhead irrigation for spring frost/freeze protection, in addition to irrigated and nonirrigated unprotected plots. Winter rowcovers increased air temperatures by 1 to 2C without advancing bloom or harvest date. Significant blossom temperature differences relative to rowcover materials (≈ 1.5C) and irrigation use (≈ 1.5 to 3.0C) were detected over the course of six spring frosts. Time of application of covers (winter or spring) and irrigation in spring interacted in their effects on early yields (25 Apr.-5 May). However, rowcover and irrigation treatments did not have a significant effect on total marketable yield, yield per plant, or berry mass. In the absence of higher prices for early than late-season fruit or of more severe environmental extremes than experienced in the current study, it would be difficult to justify the added expense of rowcovers.
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Yeşilırmak, Ercan. « Analysis of Frost Probabilities in Aydın, Türkiye ». Turkish Journal of Agriculture - Food Science and Technology 10, no 8 (25 août 2022) : 1434–40. http://dx.doi.org/10.24925/turjaf.v10i8.1434-1440.5177.
Texte intégralRésumé :
Frost events are of particular importance for plants. Its occurrence determines growing season. Early or late frost events may cause injuries and damage in plants which have not yet entered dormancy in fall/winter, and for plants in flowering period in winter/spring. Global average temperature increase has been accompanied by changes in extreme temperature events. Observations have shown that there has been a decreasing pattern in frequencies and intensities of frost events. In this sense, it is aimed in this study to analyse probabilities of frost occurrences within the latest 30-year climatic normal period, from the cold period of 1991-1992 to that of 2020-2021, at five locations (Aydın, Kuşadası, Nazilli, Söke ve Sultanhisar) in the province Aydın, western Türkiye. Six frost indices were selected, and three temperature thresholds to define frost were considered when daily minimum temperature (TMIN) being equal to or less than 0.0, -1.2 or -2.3°C.The selected frost indices are first fall frost (FFF), last spring frost (LSF), frost period (FP), number of frost days (NFD), dates of frost occurrences (DFO) and consecutive frost days (CFD). The results revealed that Nazilli and Sultanhisar are characterized by the highest probabilities of frost in terms of frequency, intensity and duration, along with the earliest occurrence of first fall frost and latest occurrences of last spring frost, and with longest duration of frost period. On the other hand, Kuşadası and Söke have opposite characteristics in comparison to Nazilli an Sultanhisar. Aydın lies in between them. The results are expected to provide information to schedule the agricultural activities, and to avoid detrimental impacts of frost events.
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Zaremuk, Rimma, Yulia Dolya et Tatiana Kopnina. « Realization of sweet cherry varieties productivity in stressful conditions in the south of Russia ». BIO Web of Conferences 34 (2021) : 01005. http://dx.doi.org/10.1051/bioconf/20213401005.
Texte intégralRésumé :
The main stress factors for sweet cherries in the Krasnodar region are: late return frosts and early exposure to frost after a warm autumn. Against the background of late return frosts, the death of the generative organs of sweet cherry was 95%, the realization of the productive potential − 3.3%; after early spring frosts, freezing of cherry fruit buds was 30%, the realization of productive potential − 47.8%. The early impact of frost after a warm autumn, the death of the generative organs of sweet cherry was 90%, the realization of the productive potential − 5.6%. Under favorable weather conditions, i.e. in the absence of any type of stress, the yield of sweet cherry varieties reached 40.5 kg/tree or 27 t/ha, and the implementation of the production potential − 57.8%. Mathematical analysis showed a high correlation (R2 = 0.97) of the yield of varieties from the abnormal temperatures in March and the degree of exposure to stress, i.e. damage to generative organs (R2 = 0.9). Domestic varieties Alaya, Sashenka and Volshebnitsa, can be recommended for creating sustainable plantations in the south of Russia.
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Rast, Everette D., et Robert L. Brisbin. « Six-Year Effects of Two Late Spring Frosts on Appalachian Hardwoods ». Northern Journal of Applied Forestry 4, no 1 (1 mars 1987) : 26–28. http://dx.doi.org/10.1093/njaf/4.1.26.
Texte intégralRésumé :
Abstract Severe late spring frosts can kill new shoots and leaves on commercial tree species at higher elevations. A previous short-term study has shown that the resulting defoliation and dieback does not seriously affect the radial growth or mortality of most species except American beech. In this study we found that defoliation, dieback, and radial growth increment were related to species and crown class. The radial growth increment of American beech was reduced to 70% of the previous 6-yr growth during the first year after the frost. The annual growth then increased consistently over the measurement period. Black cherry and sugar maple radial increment was only reduced to 88% of the previous 6-yr growth, but subsequent increments were much more variable. Epicormic branching on the lower bole of black cherry and beech increased significantly after defoliation occurred. At elevations above 3,200 ft, managers should discourage beech regeneration if timber production is the primary management objective. The potential for higher value products may be reduced because of increased variability in growth rate. North. J. Appl. For. 4:26-28, March 1987.
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Kappel, Frank. « Sweet Cherry Cultivars Vary in Their Susceptibility to Spring Frosts ». HortScience 45, no 1 (janvier 2010) : 176–77. http://dx.doi.org/10.21273/hortsci.45.1.176.
Texte intégralRésumé :
Spring frosts can be a limiting factor for sweet cherry production and very little is known about frost susceptibility of new sweet cherry cultivars. This study reports on floral bud injury of a number of recently introduced sweet cherry cultivars after 10 spring frosts in Apr. 2008. Floral buds at the first white stage were collected from late-ripening sweet cherry cultivars that were part of a randomized and replicated evaluation block. Blossoms were selected from various positions within a tree in a 1-m band centered around 1.5 m above the ground. The blossoms were brought into the laboratory, cut open, and placed into two groups: live (green) or dead (brown or browning) pistil. ‘Staccato’ and ‘Sentennial’ were the least affected followed by ‘Lapins’ and ‘Sweetheart’. ‘Sovereign’ was most susceptible to the subfreezing temperatures in the spring of 2008. There was a reasonably good relationship between the percentage of live buds per tree in the spring and yield at harvest later in the summer.
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Szügyi-Bartha, Krisztina, Géza Bujdosó, Veronika Froemel-Hajnal, Sándor Szügyi, Éva Stefanovits-Bányai et László Szalay. « Evaluation of the frost tolerance of Hungarian-bred walnut cultivars ». Acta Biologica Szegediensis 2, no 65 (23 février 2022) : 163–70. http://dx.doi.org/10.14232/abs.2021.2.163-170.
Texte intégralRésumé :
At present very few walnut cultivars can be said to be cosmopolitan cultivars, grown widely in the walnut-producing countries of the world. Walnut (Juglans regia L.) has poor ecological adaptability, as its cultivation is greatly influenced by low temperatures during the winter dormancy period and in early spring. The breeding activities conducted in various countries are therefore of great significance. Choosing suitable locations for cultivation is of key importance if optimum yield stability is to be achieved. The introduction of foreign walnut cultivars regularly runs into problems if, despite their high yielding ability, they are unable to adapt to the Hungarian climate. In Hungary the most critical weather events for walnuts are the frequent frosts in early spring. Buds therefore need to burst late to avoid damage to the flowers. Many papers have dealt with the frost tolerance of stone fruit, but only limited information has been published on the frost tolerance of walnut. For the first time in Hungary, artificial freezing tests were performed in the present work to determine the frost tolerance of the cultivars available in Hungary. The results could be of service to Hungarian growers in choosing the most suitable cultivar.
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Guo, Xiali, Siddhartha Khare, Roberto Silvestro, Jianguo Huang, Jean-Daniel Sylvain, Sylvain Delagrange et Sergio Rossi. « Minimum spring temperatures at the provenance origin drive leaf phenology in sugar maple populations ». Tree Physiology 40, no 12 (24 juillet 2020) : 1639–47. http://dx.doi.org/10.1093/treephys/tpaa096.
Texte intégralRésumé :
Abstract Late frost can cause damage to trees, especially to the developing bud of broadleaf species in spring. Through long-term adaptation, plants adjust leaf phenology to achieve an optimal trade-off between growing season length and frost avoidance. In this study, we aim to assess ecotypic differentiation in leaf development of sugar maple populations planted in a common garden. A total of 272 sugar maple seedlings from 29 Canadian provenances were planted at the northern boundary of the natural range, and the phenological phases of bud and leaf development were monitored during spring 2019. The wide geographical area under evaluation showed a complex seasonal pattern of temperature, with spring warming occurring later in the north and close to the sea. Overall, leaf development lasted between 20 and 36 days, from the end of May to end of June. We observed different timings and rates of leaf development among provenances, demonstrating the occurrence of ecotypes in this species. Minimum April temperatures of the original sites were able to explain such differences, while maximum April temperatures were not significant. Seedlings from sites with colder minimum April temperatures completed leaf development earlier and faster. On average, leaf development diverged by up to 6 days among provenances, with minimum April temperatures ranging from −3 to 3 °C. Our results demonstrated that the avoidance of late spring frost is a driving force of leaf development in sugar maple populations. In the colder sites, the growing season is a limiting factor for tree growth. Thus, when thermal conditions become favorable in spring, an earlier growth reactivation and high metabolic activity ensure a fast leaf emission, which maximizes the period available for photosynthesis and growth. These patterns demonstrate the long-term phenological adaptation of sugar maple populations to local climatic conditions and suggest the importance of frost events for leaf development.
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Krizek, Donald, Patricia Millner, Mary Camp, David Clark, Mark Davis, Bryan Butler, John Teasdale et al. « (412) Tomato Diseases ». HortScience 40, no 4 (juillet 2005) : 1071A—1071. http://dx.doi.org/10.21273/hortsci.40.4.1071a.
Texte intégralRésumé :
Afield study of organic production of tomato (Lycopersiconesculentum Mill.) in high-tunnels was conducted in 2004. `Mountain Fresh' was transplanted 31 Mar.; `Ultra Sweet' and `Sun Leaper' were transplanted on 21 July. The primary objective was to determine the feasibility of obtaining two crops of fresh-market tomatoes by starting plants 4–8 weeks earlier than the average last spring-killing frost, and extending the growing season 4–6 weeks past the average first fall-killing frost. Plants were started at weekly intervals for 4 weeks in both seasons. Data and observations were recorded on the yield of marketable fruits, plant growth and development, and plant health. Other objectives were to evaluate: 1) the benefits of using a selective UV-blocking film on plant growth and development, disease events; and 2) compost amendments on soil improvement and disease control. Major cultural challenges included water management, soil texture/drainage, prevention of chilling injury, plant support, and adequate ventilation. Major disease/pest challenges involved stalk rot caused by Sclerotinia sclerotiorum in the spring, powdery mildew in spring and late summer, Alternaria and Septoria leaf blight in late summer, and aphids, tomato hornworm, corn earworm, and beet army worm also in late summer. In addition, macrofaunal intrusions by fox, mice, and birds occurred sporadically. Poor drainage and stalk rot in the spring necessitated relocating the tunnels to an uninfested site with better drainage. The fall crop yielded high numbers of marketable quality fruits, well beyond the 15 Oct. average killing frost date. The results suggest that with improved management, there is a considerable potential for profitable extended-season production of organic tomatoes in this region.
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Jones, G. E., et B. M. Cregg. « Budbreak and Winter Injury in Exotic Firs ». HortScience 41, no 1 (février 2006) : 143–48. http://dx.doi.org/10.21273/hortsci.41.1.143.
Texte intégralRésumé :
Seventeen Abies species were evaluated for budbreak and frost injury at four locations in Michigan. Freeze tests were conducted on four species growing at the Horticulture Teaching and Research Center to determine cold hardiness levels during winter. Species differed (P ≤ 0.0001) in their days to budbreak at all locations. Trees that had broken bud were more prone to late spring frost damage than trees yet to break bud. Species differed in chlorophyll fluorescence, bud damage, and needle damage after exposure to –44 °C. Bud, foliar, and cambium damage were correlated with chlorophyll fluorescence following freeze tests. Budbreak and midwinter cold hardiness were correlated. Species breaking bud earlier displayed greater midwinter cold hardiness than species breaking bud later. Selection criteria for future Abies introductions to the upper midwestern U.S. should include identifying species with late budbreak to reduce risk of late frost injury.
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Penrose, LDJ. « Yield of early dryland sowing of wheat with winter and spring habit in southern and central New South Wales ». Australian Journal of Experimental Agriculture 33, no 5 (1993) : 601. http://dx.doi.org/10.1071/ea9930601.
Texte intégralRésumé :
The effect on yield of early sowing of wheat, and of sowing wheats with winter habit, was assessed from routine trials from 29 sites in south and central New South Wales from 1981 to 1990. Early-sown trials were largely sown from mid to late April and conventionally late trials from mid to late May. Entries in early trials consisted of winter wheats or photoperiod-sensitive spring wheats, while photoperiod-insensitive spring wheats were sown in late trials. There was a gradual change in trial entries over the period of study. Although more variable than the late-sown trials, the early-sown trials had high yields over a wider range of sowing times and displayed less risk of frost damage. On average, winter wheats had a 6% yield advantage over late-maturing spring wheats in early-sown trials. Trials yielded 15% more when sown early than late. In comparison with quick-maturing spring wheats, winter wheats did not appear to suffer a large yield penalty when sown late. Yield of early-sown trials declined with sowing before or after the optimum sowing time of late April. There was a large reduction in yield with sowings earlier than 20 April. Yield of spring wheats declined from early May almost linearly with delay in sowing date.
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Sparrow, Stephen D., et Charles W. Knight. « Frost-seeding of summer turnip rape in the subarctic ». Canadian Journal of Plant Science 72, no 3 (1 juillet 1992) : 713–23. http://dx.doi.org/10.4141/cjps92-087.
Texte intégralRésumé :
Previous research has indicated that spring-planted summer turnip rape (Brassica rapa L.) can produce good seed yields with high oil content in subarctic Alaska. However, short growing seasons often prevent seeds from reaching full maturity, resulting in high proportions of green seeds and lowered market quality. In an attempt to allow summer turnip rape seedlings to begin growth earlier in the growing season, we planted the seeds in frozen soil in late fall and early spring. Fall seeding of summer turnip rape always resulted in low plant populations, low seed yields, and high percentages of green seeds. Percentages of green seeds were highly variable and early spring seedings did not result in significantly lower percentages of green seeds than conventional (May) seedings. The effects of early spring frost-seeding on plant populations and seed yields were variable but only rarely did early spring seeding produce significantly higher seed yields than conventional seeding. Planting into barley (Hordeum vulgare L.) stubble resulted in poor stands which produced low seed yields. This study did not indicate any advantage from fall planting of summer turnip rape. Results from spring frost-seeding were not consistent; therefore, this practice cannot be recommended until these inconsistencies are better understood.Key words: Frost-seeding, summer turnip rape, subarctic, Alaska
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Díaz, R., et J. Fernández-López. « Genetic variation at early ages for several traits of interest for timber-production breeding of Juglans regia ». Canadian Journal of Forest Research 35, no 2 (1 février 2005) : 235–43. http://dx.doi.org/10.1139/x04-162.
Texte intégralRésumé :
Several traits of common walnut (Juglans regia L.) were assessed during the first three growing seasons in a progeny test of 43 open-pollinated families at two sites in northwestern Spain. Variance components, heritabilities and correlations between traits were calculated for all characteristics measured. Significant differences were found among families with regard to growth, phenology, frost damage, number of apical branches, and Phytophthora cinnamomi Rands damage, but not for growth-habit traits (number of branches, stem form, and apical dominance). Heritabilities were moderate for total height (h2i ≥ 0.32; h2f ≥ 0.63) and late-spring frost damage (h2i = 0.29; h2f = 0.57), high for resistance to P. cinnamomi (h2i = 0.76; h2f = 0.85), and low for phenology (h2i = 0.15; h2f = 0.39 for bud burst, and h2i = 0.140.36; h2f= 0.440.70 for leaf fall) and root-collar diameter (h2i = 0.180.29; h2f = 0.410.58). High ageage correlations were found for growth and phenology traits during the first three growing seasons. Some interesting correlations were also found between several of the traits studied. The families whose buds burst the earliest had more late-spring frost damage and, consequently, more apical branches (i.e., branches near the apical bud). Furthermore, the greater the resistance to P. cinnamomi and frost damage, the taller the families.
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Emerson, Jennifer L., John Frampton et Steven E. McKeand. « Genetic Variation of Spring Frost Damage in 3-year-old Fraser Fir Christmas Tree Plantations ». HortScience 41, no 7 (décembre 2006) : 1531–36. http://dx.doi.org/10.21273/hortsci.41.7.1531.
Texte intégralRésumé :
A series of open-pollinated progeny tests of Fraser fir [Abies fraseri (Pursh) Poir.] was analyzed to determine genetic variation of spring frost damage to the terminal leader and lateral branches after a late season frost in May of the third year in the field. The level of spring frost damage was also compared with bud flush dates that had been measured in the nursery before field planting. Seed sources differed significantly for lateral branch frost damage, and families within source differed significantly for both terminal leader and lateral branch frost damage. Greater terminal and lateral frost damage were significantly associated with greater height for all years. As expected, parent elevation was negatively associated with progeny height. Less lateral frost damage was also associated with later terminal and lateral bud flush dates in the nursery. In addition, higher parent elevation was associated with later lateral bud flush dates of progeny in the nursery. Terminal and lateral bud flush dates in the nursery showed high individual tree within-population heritability values of 0.85 and 0.73, respectively. Similar heritability values for the frost damage measurements were low, 0.045 for terminal leader damage and 0.14 for lateral branch damage. Many of the fast-growing families quickly made up for any loss of height from frost damage so that frost damage should not greatly affect the rotation length.
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Gehrmann, Friederike, Iida-Maria Lehtimäki, Heikki Hänninen et Timo Saarinen. « Sub-Arctic alpine Vaccinium vitis-idaea exhibits resistance to strong variation in snowmelt timing and frost exposure, suggesting high resilience under climatic change ». Polar Biology 43, no 10 (25 août 2020) : 1453–67. http://dx.doi.org/10.1007/s00300-020-02721-3.
Texte intégralRésumé :
Abstract In tundra ecosystems, snow cover protects plants from low temperatures in winter and buffers temperature fluctuations in spring. Climate change may lead to reduced snowfall and earlier snowmelt, potentially exposing plants to more frequent and more severe frosts in the future. Frost can cause cell damage and, in combination with high solar irradiance, reduce the photochemical yield of photosystem II (ΦPSII). Little is known about the natural variation in frost exposure within individual habitats of tundra plant populations and the populations’ resilience to this climatic variation. Here, we assessed how natural differences in snowmelt timing affect microclimatic variability of frost exposure in habitats of the evergreen Vaccinium vitis-idaea in sub-Arctic alpine Finland and whether this variability affects the extent of cell damage and reduction in ΦPSII. Plants in early melting plots were exposed to more frequent and more severe frost events, and exhibited a more pronounced decrease in ΦPSII, during winter and spring compared to plants in late-melting plots. Snowmelt timing did not have a clear effect on the degree of cell damage as assessed by relative electrolyte leakage. Our results show that sub-Arctic alpine V. vitis-idaea is currently exposed to strong climatic variation on a small spatial scale, similar to that projected to be caused by climate change, without significant resultant damage. We conclude that V. vitis-idaea is effective in mitigating the effects of large variations in frost exposure caused by differences in snowmelt timing. This suggests that V. vitis-idaea will be resilient to the ongoing climate change.
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Li, Wenjie, Jingfeng Huang, Lingbo Yang, Yan Chen, Yahua Fang, Hongwei Jin, Han Sun et Ran Huang. « A Practical Remote Sensing Monitoring Framework for Late Frost Damage in Wine Grapes Using Multi-Source Satellite Data ». Remote Sensing 13, no 16 (14 août 2021) : 3231. http://dx.doi.org/10.3390/rs13163231.
Texte intégralRésumé :
Late frost damage is one of the main meteorological disasters that affect the growth of wine grapes in spring, causing a decline in wine grapes quality and a reduction in yield in Northwest China. At present, remote sensing technology has been widely used in the field of crop meteorological disasters monitoring and loss assessments, but little research has been carried out on late frost damage in wine grapes. To monitor the impact of late frost in wine grapes accurately and quickly, in this research, we selected the Ningxia planting area as the study area. A practical framework of late frost damage on wine grapes by integrating visible, near-infrared, and thermal infrared satellite data is proposed. This framework includes: (1) Wine grape planting area extraction using Gaofen-1 (GF-1), Landsat-8, and Sentinel-2 based on optimal feature selection and Random Forest (RF) algorithm; (2) retrieval of the land surface temperature (LST) using Landsat-8 thermal infrared data; (3) data fusion using Landsat-8 LST and MODIS LST for a high spatiotemporal resolution of LST with the Enhanced Spatial and Temporal Adaptive Reflectance Fusion Model (ESTARFM); (4) the estimation of daily minimum air temperature (Tmin) using downscaled LST and meteorological station data; (5) monitoring and evaluation of the degree of late frost damage in wine grapes in April 2020 by combining satellite-derived data and late frost indicators. The results show that the total area of wine grapes extracted in Ningxia was about 39,837 ha. The overall accuracy was 90.47%, the producer’s accuracy was 91.09%, and the user’s accuracy was 90.22%. The root mean square (RMSE) and the coefficient of determination (R2) of the Tmin estimation model were 1.67 ℃ and 0.91, respectively. About 41.12% of the vineyards suffered severe late frost damage, and the total affected area was about 16,381 ha during April 20–25, 2020. This suggests the satellite data can accurately monitor late frost damage in wine grapes by mapping the wine grape area and estimating Tmin. The results can help farmers to take remedial measures to reduce late frost damage in wine grapes, and provide an objective evaluation of late frost damage insurance claims for wine grapes. With the increasing weather extremes, this study has an important reference value for standardized global wine grape management and food security planning.
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Magugu, John W., Song Feng, Qiuqiong Huang, Yongjun Zhang et Grant H. West. « Analysis of future climate scenarios and their impact on agriculture in eastern Arkansas, United States ». Journal of Water and Land Development 37, no 1 (1 juin 2018) : 97–112. http://dx.doi.org/10.2478/jwld-2018-0029.
Texte intégralRésumé :
Abstract Impact of climate change on crop growth is dynamic and difficult to quantify due to heterogeneity of the associated effects and their interactions within the Earth system. The main objective of this study is to establish how future climate change might affect agriculture, through an assessment of temperature and precipitation driven parameters. These include percentage number of rainy days with extreme precipitation, percentage of extreme precipitation relative to wet days, first fall frost days, last spring frost days, growing degree days, growing season length and the total precipitation. Results show modest increase in total precipitation with a slight increase in extreme precipitation, representing up to 2.2% increase by 2060 under representative concentration pathway (RCP 8.5) scenario. There would be late first fall frost days, early last spring frost days and increased growing season length by up to 2 weeks in 2060. The growing degree days are projected to increase under all scenarios for all crops, with cotton showing the largest increase of up to 37% relative to the baseline period.
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Carter, P. R. « Late Spring Frost and Postfrost Clipping Effect on Corn Growth and Yield ». Journal of Production Agriculture 8, no 2 (avril 1995) : 203–9. http://dx.doi.org/10.2134/jpa1995.0203.
Texte intégral
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Vega-Semorile, Sandra E., John B. Bamberg et Jiwan P. Palta. « Evidence for Genetic Variability in the Speed of Cold Acclimation among Tuber-bearing Wild Potato Species ». HortScience 30, no 4 (juillet 1995) : 775G—776. http://dx.doi.org/10.21273/hortsci.30.4.775g.
Texte intégralRésumé :
Frost damage to the foliage is a common problem where potatoes are grown, and results in significant reductions in tuber yield. Frost injury also limits the cultivation of high-yielding S. tuberosum cultivars in the mountain regions of Central and South America, where potato is a staple crop. Recent studies have shown that some wild potato species possess a high degree of non-acclimated frost tolerance (growing in normal conditions) as well as high cold acclimation capacity (able to increase frost tolerance upon exposure to cold). Natural frosts affecting potatoes are of two types: a) late spring or early fall frost, where the minimum temperature during the frost episode can be very low; b) frost during the growing season, where the minimum temperature during the frost episode is not as low. It is expected that potato species able to acclimate rapidly would survive better from the latter type of frosts, whereas species having higher acclimation capacity might have a great chance to survive better from the former type of frosts. The objective of this study was to find out if there is genetic variability for the speed of acclimation among different tuber-bearing wild potato species. The species used were: S. acaule, S. commersonii, S. megistacrolobum, S. multidissectum, S. polytrichon, S. sanctae-rosae, and S. toralapanum. Relative freezing tolerance of these species was measured during cold acclimation. Preliminary results suggest that there are differences in the speed of acclimation among these species. We found that these species can be divided into four groups: i) non-acclimators; ii) rapid acclimators, with low to medium acclimation capacity; iii) slow acclimators, with low to medium acclimation capacity; iv) slow acclimators, with high acclimation capacity. We plan to use this information in our breeding program aimed at improving the freezing tolerance of potatoes.
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Vega-Semorile, Sandra E., John B. Bamberg et Jiwan P. Palta. « Evidence for Genetic Variability in the Speed of Cold Acclimation among Tuber-bearing Wild Potato Species ». HortScience 30, no 4 (juillet 1995) : 775G—776. http://dx.doi.org/10.21273/hortsci.30.4.775.
Texte intégralRésumé :
Frost damage to the foliage is a common problem where potatoes are grown, and results in significant reductions in tuber yield. Frost injury also limits the cultivation of high-yielding S. tuberosum cultivars in the mountain regions of Central and South America, where potato is a staple crop. Recent studies have shown that some wild potato species possess a high degree of non-acclimated frost tolerance (growing in normal conditions) as well as high cold acclimation capacity (able to increase frost tolerance upon exposure to cold). Natural frosts affecting potatoes are of two types: a) late spring or early fall frost, where the minimum temperature during the frost episode can be very low; b) frost during the growing season, where the minimum temperature during the frost episode is not as low. It is expected that potato species able to acclimate rapidly would survive better from the latter type of frosts, whereas species having higher acclimation capacity might have a great chance to survive better from the former type of frosts. The objective of this study was to find out if there is genetic variability for the speed of acclimation among different tuber-bearing wild potato species. The species used were: S. acaule, S. commersonii, S. megistacrolobum, S. multidissectum, S. polytrichon, S. sanctae-rosae, and S. toralapanum. Relative freezing tolerance of these species was measured during cold acclimation. Preliminary results suggest that there are differences in the speed of acclimation among these species. We found that these species can be divided into four groups: i) non-acclimators; ii) rapid acclimators, with low to medium acclimation capacity; iii) slow acclimators, with low to medium acclimation capacity; iv) slow acclimators, with high acclimation capacity. We plan to use this information in our breeding program aimed at improving the freezing tolerance of potatoes.
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Rochette, P., G. Bélanger, Y. Castonguay, A. Bootsma et D. Mongrain. « Climate change and winter damage to fruit trees in eastern Canada ». Canadian Journal of Plant Science 84, no 4 (1 octobre 2004) : 1113–25. http://dx.doi.org/10.4141/p03-177.
Texte intégralRésumé :
Climatic conditions during the cold season represent a serious constraint to fruit production in eastern Canada. Meteorological models predict that temperatures of winter months will increase by 2 to 6°C by 2050. The possible impact of climate change on fruit trees in eastern Canada was assessed using agroclimatic indices expressing the risks associated with known causes of damage during fall, winter, and spring. Indices were calculated for 15 agricultural regions in eastern Canada for recent (1961–1990) and future periods (2010–2039 and 2040–2069) using temperature and precipitation data predicted by the Canadian Global General Circulation Model (CGCMI). Averaged across all agricultural regions, the first fall frost in 2040–2069 would be delayed by 16 d while the last spring frost (≤-2°C) would be advanced by 15 d. By 2040 to 2069, the risks of damage to fruit trees by early winter frosts in eastern Canada are likely to decrease because the shorter photoperiod at the time of the first fall frost would result in a longer hardening period. Milder winter temperatures will also reduce the cold stress as the accumulation of cold degree-days (<-15°C) would be reduced and the annual minimum temperature would be increased in all regions of eastern Canada. More frequent winter thaw events, however, would result in a loss of hardiness and in a thinner snow cover that would increase the plant vulnerability to subsequent extreme sub-freezing temperatures. The risk of damage to flower buds by a late frost would increase in southern Ontario, remain almost unchanged in the Maritimes and Ottawa Valley-southern Québec regions, and decrease in the Continental North. The projected climate change should allow for the introduction of new varieties and species where fruit trees are currently grown and for an extension further north of the commercial production in eastern Canada. Key words: Overwintering, fruit production, climatic indices, winter injury, spring frost
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Talanova, Galina I. « Climate of the reserve «Malaya Sosva» : long-term material ». Environmental Dynamics and Global Climate Change 9, no 1 (6 juin 2018) : 22–45. http://dx.doi.org/10.17816/edgcc8946.
Texte intégralRésumé :
The article presents an analysis of meteorological long-term material on the territory of the reserve “Malaya Sosva” (Sosvinsky Priobie). The climate of the reserve is typically continental. Long winter, short summer, late spring and early autumn frosts are characteristic of reserve. There are also sharp fluctuations in temperature throughout the year. The frost-free period in the air lasts 78 days. Annual precipitation is 544 mm. The snow cover is an average of 194 days (more than 6 months). Since 1981, there has been an increase in the average annual air temperature from decade to decade by approximately 0.5 ° C.
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KHANIZADEHI, S., D. BUSZARD, M. A. FANOUS et C. G. ZARKADAS. « EFFECT OF CROP LOAD ON SEASONAL VARIATION IN CHEMICAL COMPOSITION AND SPRING FROST HARDINESS OF APPLE FLOWER BUDS ». Canadian Journal of Plant Science 69, no 4 (1 octobre 1989) : 1277–84. http://dx.doi.org/10.4141/cjps89-155.
Texte intégralRésumé :
Spring frost hardiness and fluctuations in nitrogen (N), phosphorous (P), potassium (K), glucose, fructose, sorbital, and starch were compared in spur buds of bearing and noncropped mature McIntosh/M7 trees (Malus pumila Mill.). Deblossoming caused more flowers to be initiated for the next season and flower buds were larger and heavier. Sorbitol was the predominant soluble carbohydrate in both years and was higher in the buds of noncropped trees during most of the year. Buds of deblossomed trees also had higher contents of glucose and starch. In both noncropped and cropped trees total starch increased during cold acclimation and decreased during late winter and early spring. Fructose content was not affected by crop load. Bud content of N, P, and K was lower on cropped trees throughout the sampling period. On cropped trees buds were more susceptible to low temperature injury during spring.Key words: Malus pumila, sugar, conductivity, freezing tolerance, spring frost
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Meyer, Benjamin F., Allan Buras, Konstantin Gregor, Lucia S. Layritz, Adriana Principe, Jürgen Kreyling, Anja Rammig et Christian S. Zang. « Frost matters : incorporating late-spring frost into a dynamic vegetation model regulates regional productivity dynamics in European beech forests ». Biogeosciences 21, no 5 (18 mars 2024) : 1355–70. http://dx.doi.org/10.5194/bg-21-1355-2024.
Texte intégralRésumé :
Abstract. Late-spring frost (LSF) is a critical factor influencing the functioning of temperate forest ecosystems. Frost damage in the form of canopy defoliation impedes the ability of trees to effectively photosynthesize, thereby reducing tree productivity. In recent decades, LSF frequency has increased across Europe, likely intensified by the effects of climate change. With increasing warming, many deciduous tree species have shifted towards earlier budburst and leaf development. The earlier start of the growing season not only facilitates forest productivity but also lengthens the period during which trees are most susceptible to LSF. Moreover, recent forest transformation efforts in Europe intended to increase forest resilience to climate change have focused on increasing the share of deciduous species in forests. To assess the ability of forests to remain productive under climate change, dynamic vegetation models (DVMs) have proven to be useful tools. Currently, however, most state-of-the-art DVMs do not model processes related to LSF and the associated impacts. Here, we present a novel LSF module for integration with the dynamic vegetation model Lund–Potsdam–Jena General Ecosystem Simulator (LPJ-GUESS). This new model implementation, termed LPJ-GUESS-FROST, provides the ability to directly attribute simulated impacts on forest productivity dynamics to LSF. We use the example of European beech, one of the dominant deciduous species in central Europe, to demonstrate the functioning of our novel LSF module. Using a network of tree-ring observations from past frost events, we show that LPJ-GUESS-FROST can reproduce productivity reductions caused by LSF. Further, to exemplify the effects of including LSF dynamics in DVMs, we run LPJ-GUESS-FROST for a study region in southern Germany for which high-resolution climate observations are available. Here, we show that modeled LSF plays a substantial role in regulating regional net primary production (NPP) and biomass dynamics, emphasizing the need for LSF to be more widely accounted for in DVMs.
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Fallah, Mehdi, Mousa Rasouli, Darab Hassani, Shaneka S. Lawson, Saadat Sarikhani et Kourosh Vahdati. « Tracing Superior Late-Leafing Genotypes of Persian Walnut for Managing Late-Spring Frost in Walnut Orchards ». Horticulturae 8, no 11 (28 octobre 2022) : 1003. http://dx.doi.org/10.3390/horticulturae8111003.
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Evaluating genetic diversity in walnut (Juglans regia L.) populations is a rapid approach used by walnut breeding programs to distinguish superior genotypes. The present study was conducted on the walnut population of Hamedan Province, one of the richest and most genetically diverse regions in Iran, during 2018–2019. After the initial screening, 47 genotypes were selected for further evaluation of pomological and phenological traits based on International Plant Genetic Resources Institute (IPGRI) descriptors. Nut and kernel weights among the selected genotypes ranged from 7.15 to 21.05 g and 3.0 to 10.8 g, respectively. Principal component analysis (PCA) categorized the genotypes into three distinct groups. Whereas the cluster analysis (CA) revealed the similarities and dissimilarities among the genotypes by identifying four major clusters. Spearman correlation analysis showed a positive correlation (p < 0.01) between nut weight (NWT), nut size, and kernel weight (KW), while a negative correlation (p < 0.01) between shell thickness (STH) and packing tissue thickness (PTT) with kernel percentage (KP) was observed. Lastly, 10 of 47 genotypes (TAL8, TAL9, TAL10, TAL14, TAL19, TAL22, TB2, TB4, TB6, and RDGH5) were considered superior. Superior genotypes were late-leafing (25–40 days after the standard) and displayed a lateral bearing (LB) habit with heavy nuts (12.52–16.82 g) and kernels (6.53–8.15 g), thin shells (1.06–1.25 mm), and lightly colored kernels.
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Xu, Hao, Danielle Ediger et Mehdi Sharifi. « Horticultural Practices in Early Spring to Mitigate the Adverse Effect of Low Temperature on Fruit Set in ‘Lapins’ Sweet Cherry ». Plants 12, no 3 (19 janvier 2023) : 468. http://dx.doi.org/10.3390/plants12030468.
Texte intégralRésumé :
Yield of sweet cherry (Prunus avium L.) is determined by fruit set, a developmental stage sensitive to variable spring environmental conditions. To sustain fruit production and enhance crop climate resilience, it is important to understand the impacts of abiotic stresses and the effectiveness of horticultural mitigations in the spring on the critical developmental processes during fruit set. In this study, flowering phenology, pistil browning and percent fruit set of ‘Lapins’ were monitored at five sites of different elevation and frost risk in the Okanagan Valley, British Columbia, Canada, in 2019 and 2022. At Site 1 in Summerland Research and Development Centre (“SuRDC1”), where a ‘Lapins’ on Krymsk 5 planting was located in a frost pocket where the crops were exposed to high risk of cold damage in the spring, a series of experiments were conducted to investigate the floral organ viability and percent fruit set under low temperatures, and under the effects of four spring horticultural mitigation measures. Installation of polyethylene sleeves and FAME spray (fatty acid methyl esters-based plant growth regulator, WAIKEN, SST Australia) were implemented in 2019; boric acid spray and postponed irrigation were tested in 2022. Low fruit set at SuRDC1 in both years was associated with severe pistil browning after night temperature dropped below −4 °C in late April. In 2019, the semi-enclosure of polyethylene sleeves led to an increase in the surface temperature (Tsurfae) of floral buds by 2–4 °C, which prolonged the stage of first bloom, delayed petal fall and prevented frost damage on pistils, but led to the decrease in percent fruit set by 77%, due to ovule abortion or cessation of fruitlet development. The early and late sprays of FAME had no significant influence on either abundance of germinated pollen tubes or percent fruit set; however, the potential of late spray in improving pollen abundance and reducing pistil browning requires further investigation. In 2022, the spray of 0.01% boric acid solution led to a decrease in fruit set by 6.95%. Six-week postponement of irrigation starting from full bloom decreased soil moisture, but increased soil temperature and improved fruit set by 7.61%. The results improved our understanding about the damages of adverse spring air temperatures on pistils and ovules, and suggested the potential of irrigation adjustment in regulating soil moisture and temperature and improving fruit set in the cool and moist spring.
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Man, Rongzhou, Gordon J. Kayahara, Qing-Lai Dang et James A. Rice. « A case of severe frost damage prior to budbreak in young conifers in Northeastern Ontario : Consequence of climate change ? » Forestry Chronicle 85, no 3 (1 juin 2009) : 453–62. http://dx.doi.org/10.5558/tfc85453-3.
Texte intégralRésumé :
In spring 2007, young planted and natural conifers suffered extensive needle and bud injury near Hearst and Kapuskasing in northeastern Ontario. Damage was observed on all species of conifers up to 20 years old and 8 m in height. Taller trees, especially those in the overstory, and young understory trees protected by a closed canopy had less damage. The damage was caused by earlier than normal loss of cold hardiness followed by late spring frosts according to damage observations, weather station data, and calculated thermal time requirements for budbreak and cold hardiness of conifers. During May 19 to 21, 2007, minimum temperatures were recorded between -8°C and -9°C, and before this period, temperatures were warm enough to induce early dehardening and loss of trees' cold hardiness. According to the historical weather data for Kapuskasing, estimated budbreak time has become earlier since 1918 and freezing temperatures during budbreak and shoot elongation (between growing degree days 100 and June 15) have become more frequent since 1980. If the trend towards earlier budbreak is due to climate change, then the type of frost damage we observed in northeastern Ontario in 2007 could become more common. We discuss implications of such events and suggest research needed to understand the risk of frost damage with climatic warming and to reduce damage. Key words: conifer frost damage, mature needle and bud (or needle/bud) mortality, early dehardening and budbreak (or dehardening/budbreak), climatic warming
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Wang, Weiling, Yuting Zhang, Chang Liu, Yongwen Dong, Xue Jiang, Can Zhao, Guohui Li, Ke Xu et Zhongyang Huo. « Label-Free Quantitative Proteomics Reveal the Mechanisms of Young Wheat (Triticum aestivum L.) Ears’ Response to Spring Freezing ». International Journal of Molecular Sciences 24, no 21 (2 novembre 2023) : 15892. http://dx.doi.org/10.3390/ijms242115892.
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Late spring frost is an important meteorological factor threatening the safe production of winter wheat in China. The young ear is the most vulnerable organ of the wheat plant to spring frost. To gain an insight into the mechanisms underpinning young wheat ears’ tolerance to freezing, we performed a comparative proteome analysis of wheat varieties Xumai33 (XM33, freezing-sensitive) and Jimai22 (JM22, freezing-tolerant) under normal and freezing conditions using label-free quantitative proteomic techniques during the anther connective tissue formation phase (ACFP). Under freezing stress, 392 and 103 differently expressed proteins (DEPs) were identified in the young ears of XM33 and JM22, respectively, and among these, 30 proteins were common in both varieties. A functional characterization analysis revealed that these DEPs were associated with antioxidant capacity, cell wall modification, protein folding, dehydration response, and plant–pathogen interactions. The young ears of JM22 showed significantly higher expression levels of antioxidant enzymes, heat shock proteins, and dehydrin under normal conditions compared to those of XM33, which might help to prepare the young ears of JM22 for freezing stress. Our results lead to new insights into understanding the mechanisms in young wheat ears’ response to freezing stress and provide pivotal potential candidate proteins required for improving young wheat ears’ tolerance to spring frost.
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Rowland, Lisa J., Elizabeth L. Ogden, Mark K. Ehlenfeldt et Rajeev Arora. « Cold Tolerance of Blueberry Genotypes Throughout the Dormant Period from Acclimation to Deacclimation ». HortScience 43, no 7 (décembre 2008) : 1970–74. http://dx.doi.org/10.21273/hortsci.43.7.1970.
Texte intégralRésumé :
Cold hardiness in woody perennials is determined by complex interacting factors: the timing and rate of cold acclimation; the maximum level of cold tolerance attained; the maintenance of cold tolerance during the winter; and the rate of loss of cold tolerance or deacclimation on resumption of spring growth. For highbush blueberry, the degree of winter freezing tolerance and susceptibility to spring frosts have been identified as the most important genetic limitations of current cultivars. Depending on the winter and the location, both winter freezes and spring frosts can cause damage to floral buds or flowers resulting in substantial losses in yield. To identify genotypes that are particularly slow or late to deacclimate and thus may be useful in breeding for spring frost-tolerant cultivars, we compared deacclimation kinetics under controlled laboratory and field conditions among several blueberry genotypes with diverse genetic backgrounds. Clear genotypic differences in timing and rate of deacclimation were found. In the field study, the species Vaccinium constablaei Gray was identified as particularly late to deacclimate, and ‘Little Giant’ (50:50 hybrid of V. constablaei and V. ashei Reade) was nearly as late to deacclimate as 100% V. constablaei. Recently, we extended our cold tolerance measurements from October through midwinter comparing acclimation kinetics and maximum cold tolerance levels among genotypes. Although all genotypes appeared to reach maximum cold tolerance about mid-December under the study conditions, genotypic differences were detected in other aspects, including initial cold tolerance, rate of acclimation, maximum cold tolerance, and length of the plateau. ‘Little Giant’ and ‘Northsky’ (75:25 hybrid of V. corymbosum L. and V. angustifolium Ait.) were very early to acclimate and were hardier than the other genotypes both initially and when maximum cold tolerance was reached. Understanding how cold tolerance levels change throughout the dormant period should help us to develop cultivars better suited to their environments.
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Frota de Albuquerque Landi, Fabiana, Alessia Di Giuseppe, Alberto Maria Gambelli, Alberto Palliotti, Andrea Nicolini, Anna Laura Pisello et Federico Rossi. « Life Cycle Assessment of an Innovative Technology against Late Frosts in Vineyard ». Sustainability 13, no 10 (17 mai 2021) : 5562. http://dx.doi.org/10.3390/su13105562.
Texte intégralRésumé :
Wine production is a key sector for the Italian economy, representing 13 billion euros per year. The proportion of the market raises concerns about improving the production technology at low cost, safe practices, and low environmental impacts. The recurrent life cycle assessment performed does not report on the impacts of frost protection. This study presents the potential environmental impact of a novel late frost protection technique for vineyards that is currently under development. It consists of an organic coating made of sugar and straw to prevent vine damage due to frosts in vineyards in the coldest hours of late winter and early spring. From previous research at the University of Perugia (Italy), the technique has proven to be an effective protection method for vine shoots. Currently, the yields are protected by highly energy-demanding methods. For this study, we simulated two different scenarios of frosting protection so we could point out possible hotspots for the field application of the novel method and compare it to a technique usually employed in central Italy. Under the Centrum voor Milieukunde Leiden (CML) method, the cotton candy technique is estimated at 316 kg CO2 equivalent emissions for hectare. Employing the organic sugar-coating means avoiding 69,375 kg of CO2 eq. compared to the traditional technique of oak wood-burning into the vineyard. Preliminary cost analysis demonstrated the economic viability of implementing the organic coating.