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Sample records for budbreak

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

    Science.gov (United States)

    Pope, Katherine S.; Dose, Volker; Da Silva, David; Brown, Patrick H.; DeJong, Theodore M.

    2015-06-01

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

  2. Axillary budbreak in a cut rose crop as influenced by light intensity and red:far-red ratio at bud level

    NARCIS (Netherlands)

    Wubs-Timmermans, A.M.; Heuvelink, E.; Marcelis, L.F.M.; Buck-Sorlin, G.H.; Vos, J.

    2014-01-01

    When flower-bearing shoots in cut rose (Rosa ·hybrida) are harvested, a varying number of repressed axillary buds on the shoot remainder start to grow into new shoots (budbreak). Earlier experiments indicated that light reaching the bud affected the number of budbreaks. In all these studies, whole p

  3. Efeito do frio e do desponte na brotação de gemas em pessegueiro Chilling and tipping off pruning effect on budbreak in peach trees

    Directory of Open Access Journals (Sweden)

    Fernando José Hawerroth

    2009-06-01

    Full Text Available O objetivo do trabalho foi avaliar a resposta de três cultivares de pessegueiro quanto à brotação de gemas, em ramos com ou sem desponte, quando submetidas a diferentes períodos de exposição ao frio. Ramos de ano das cultivares Coral, Eragil e Rubidoux foram submetidas ao frio complementar (0; 312; 624 e 1.248 unidades de frio. Posteriormente, metade dos ramos foram mantidos inteiros e nos demais efetuou-se o desponte, com a retirada da gema apical. Os ramos foram mantidos em câmara de crescimento a 25ºC, sendo avaliado o percentual de brotação de gemas vegetativas e floríferas aos 15 e 30 dias após início da exposição a 25ºC. O desponte incrementou a brotação de gemas vegetativas em todas as cultivares avaliadas. O efeito do desponte sobre a brotação das gemas vegetativas foi variável conforme as unidades de frio aos quais os ramos foram expostos, sendo evidenciado maior efeito do desponte nos tratamentos com maior exposição ao frio.The objective of this work was to evaluate the behavior of three peach cultivars in relation to budbreak in branches with or without tipping off pruning submitted to different exposition cold periods. One-year-old branches of Coral, Eragil and Rubidoux peach trees cultivars were submitted to chilling supplement (0, 312, 624 and 1248 cold units. After chilling treatments, half of branches were maintained intact and others were tipped off pruning through terminal bud remove. After this, the branches were kept in growth chamber at 25ºC, and it was evaluated the percentage of budbreak in flower and vegetative buds at 15 and 30 days after the beginning of the exposure at 25ºC. Tipping off pruning increased budbreak in vegetative buds in all cultivars studied. The effect of tipping off pruning on budbreak in vegetative buds was variable depending on chilling intensity that the branches were submitted, being evidenced bigger effect of tipping off pruning in higher chilling exposure.

  4. Estimation of chilling requirement and effect of hydrogen cyanamide on budbreak and fruit characteristics of 'superior seedless' table grape cultivated in a mild winter climate

    International Nuclear Information System (INIS)

    The chilling requirement and optimum time for hydrogen cyanamide (HC) application were determined for Superior Seedless table grape grown in southern Tunisia, an arid mild winter region. The reliability of five models to predict chilling accumulation for this cultivar was also investigated. In mid-November, current season shoots were excised and subjected to artificial chilling at 7 deg. C for different lengths of time. Each time, half the shoots were treated with a 2% (v/v) aqueous solution of HC, the others were sprayed with distilled water. Thereafter, these shoots were forced to budburst. Rest intensity gradually declined due to chilling accumulation. We estimated that the cultivar needed approx. 440 hours (h) of chilling, or chilling requirement (CR), to overcome endodormancy. During two dormant seasons, estimation of chilling accumulation showed that the Positive Chill Unit model was the most suitable to predict rest completion for Superior Seedless grown under our climatic conditions. Using this model, we found that the variety's CR was not always met by mid-February. In both laboratory and field trials, HC was most effective in enhancing and advancing budbreak if applied when approx. 2/3 of the cultivar's CR were met. Moreover, by this application berry weight and diameter were increased and fruit maturity was advanced. Our study indicated that HC (2%) was effective in advancing budbreak and fruit maturity of Superior Seedless table grape although its effectiveness depended on application date. (author)

  5. Involvement of EARLY BUD-BREAK, an AP2/ERF Transcription Factor Gene, in Bud Break in Japanese Pear (Pyrus pyrifolia Nakai) Lateral Flower Buds: Expression, Histone Modifications and Possible Target Genes.

    Science.gov (United States)

    Anh Tuan, Pham; Bai, Songling; Saito, Takanori; Imai, Tsuyoshi; Ito, Akiko; Moriguchi, Takaya

    2016-05-01

    In the Japanese pear (Pyrus pyrifolia Nakai) 'Kosui', three developmental stages of lateral flower buds have been proposed to occur during ecodormancy to the flowering phase, i.e. rapid enlargement, sprouting and flowering. Here, we report an APETALA2/ethylene-responsive factor (AP2/ERF) transcription factor gene, named pear EARLY BUD-BREAK (PpEBB), which was highly expressed during the rapid enlargement stage occurring prior to the onset of bud break in flower buds. Gene expression analysis revealed that PpEBB expression was dramatically increased during the rapid enlargement stage in three successive growing seasons. PpEBB transcript levels peaked 1 week prior to onset of bud break in 'Kosui' potted plants treated with hydrogen cyanamide or water under forcing conditions. Chromatin immunoprecipitation-quantitative PCR showed that higher levels of active histone modifications (trimethylation of the histone H3 tail at Lys4) in the 5'-upstream and start codon regions of the PpEBB gene were associated with the induced expression level of PpEBB during the rapid enlargement stage. In addition, we provide evidence that PpEBB may interact with and regulate pear four D-type cyclin (PpCYCD3) genes during bud break in 'Kosui' lateral flower buds. PpEBB significantly increased the promoter activities of four PpCYCD3 genes in a dual-luciferase assay using tobacco leaves. Taken together, our findings uncovered aspects of the bud break regulatory mechanism in the Japanese pear and provided further evidence that the EBB family plays an important role in bud break in perennial plants. PMID:26940832

  6. AN INVESTIGATION ON THE BUD-BREAK AND GROWTH OF CUTTINGS OF 420 A AND 5 BB AMERICAN VINE ROOTSTOCKS IRRADIATED WITH DIFFERENT GAMMA DOSES

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    Alper DARDENIZ

    2006-02-01

    Full Text Available Viticulture is an important and intensive agricultural branch in Çanakkale province and also in Turkey. Different American vine rootstocks are widely used against phylloxera in our country. Plant breeders have been using gamma radiation for creating new varieties of crops and for obtaining broad genetic diversity for years. In this study, four different doses of gamma rays were applied to 420 A and 5 BB American vine rootstocks when the buds on the cuttings were at the dormant stage. Then, effects of different gamma radiation doses on the cuttings of 420 A and 5 BB American vine rootstocks were investigated. The aim of the research was to study the effect of different gamma radiation doses on some growth parameters of cuttings of 420 A and 5 BB, and to determine the GR50 dose. The results obtained were statistically elaborated by TARIST.

  7. AN INVESTIGATION ON THE BUD-BREAK AND GROWTH OF CUTTINGS OF 420 A AND 5 BB AMERICAN VINE ROOTSTOCKS IRRADIATED WITH DIFFERENT GAMMA DOSES

    OpenAIRE

    Dardeniz, Alper; TAYYAR, Şemun

    2005-01-01

    Viticulture is an important and intensive agricultural branch in Çanakkale province and also in Turkey. Different American vine rootstocks are widely used against phylloxera in our country. Plant breeders have been using gamma radiation for creating new varieties of crops and for obtaining broad genetic diversity for years. In this study, four different doses of gamma rays were applied to 420 A and 5 BB American vine rootstocks when the buds on the cuttings were at the dormant stage. Then, ef...

  8. Necessidade de frio para quebra de dormência de gemas de caquizeiro 'Fuyu' Chill requirement for budbreak of japanese persimmon cv. Fuyu

    Directory of Open Access Journals (Sweden)

    Rudival Faquim

    2007-01-01

    Full Text Available Objetivou-se, no presente trabalho, determinar a necessidade de frio para a quebra da dormência das gemas de caquizeiro 'Fuyu'. As coletas de ramos foram realizadas em cinco datas (26-04, 14-05, 21-06, 19-07 e 16-08. Foram aplicados nos ramos cinco tratamentos de frio adicional (0; 168; 336; 504; 672 h de frio em geladeira à temperatura de 4ºC a 7ºC. A avaliação da dormência foi feita pelo teste biológico de estacas de nós isolados por meio do tempo médio para brotação (TMB, velocidade de brotação (VB, taxa final de brotação (TF e taxa de brotações vigorosas (TBV. O delineamento experimental adotado foi o completamente casualizado, num esquema fatorial 5 x 5 (cinco datas e cinco tempos de exposição ao frio, com três repetições. Foram realizados testes separadamente com gemas terminais e com gemas laterais. A quebra de dormência de gemas laterais e terminais de ramos de caquizeiro 'Fuyu' ocorreu no mês de agosto, após o tratamento com 504 h de frio, de 4ºC a 7ºC, obtendo-se 100% de gemas brotadas.This work aimed to evaluate the chill requirement for bud break of Japanese persimmon cv. Fuyu. The branches were collected in five dates (April 26th; May 14th; June 21st; July 19th, and August 16th and received five chill treatments (0, 168, 336, 504, 672 h in the refrigerator (4ºC to 7ºC. The evaluation of dormancy was observed by the biological test of single node cuttings by following variables: average time for budburst (TMB, velocity of budburst (VB, final rate of budburst (TF and rate of vigorous budburst (TBV. The experimental design was a factorial entirely randomized with five dates and five periods of chill treatment with three replications. Terminal and lateral buds were analyzed individually. The bud break of terminal and lateral buds of Japanese persimmon cv. Fuyu occurred in August after the treatment with 504 h of chill (4ºC to 7ºC, when 100% of budburst was obtained.

  9. Organic Alternative for Breaking Dormancy in Table Grapes Grown in Hot Regions

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    Consuelo Corrales-Maldonado

    2010-01-01

    Full Text Available Problem statement: In warm-winter regions, the need for intervention of chemical means to break bud rest becomes a dominant factor for maintaining economic production of table grapes. However, the problem is more acute when farmers want to grow organic table grapes in the absence of environmentally-friendly budbreak promoters. Approach: This study aimed to evaluate the effect of a mix of naturally occurring Garlic Compounds (GC in comparison to the conventional use of hydrogen cyanamide to promote budbreak and its effects on cluster quality in four table grape cultivars field-grown in hot region (Sonora Desert. Results: Four cultivars responded to GC, the vines bursting bud about 3 weeks after application. Quality of fruit from 4 cultivars treated with GC was excellent. Clusters weigh and berry sizes were larger than other treatments. Conclusion: Ability of GC to break dormancy in table grape grown in Sonora Desert has significant implications for organic table grape production in hot regions.

  10. INFLUENCE OF LOW-FREQUENCY ELECTROMAGNETIC FIELD ON THE VEGETATIVE GROWTH OF GRAPE CV. USLU

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    Alper DARDENIZ

    2007-04-01

    Full Text Available Low-frequency electromagnetic fi eld (ELF at 50 Hz, 0.15 mT was applied to canes of ‘Uslu’ grape for 5, 10, 15 and 20 minutes. The canes were prepared by cutting them into 50-60 mm one-bud scions. The scions were planted with the density of 40 x 40 mm into propagation boxes. The experiment was arranged in randomized complete blocks design with 4 replicates and each replicate consisted of 15 scions. The parameters of vigour (shoot growth of the fi rst three weeks, bud-break percentage of the fi rst three weeks, bud-break percentage, vigour, rooting percentage, root development, root weight, number of root, shoot length, shoot weight, number of node, node height, root/shoot weight and shoot + root weight were included in the study. As a result, different durations of 50 Hz frequency resulted in signifi cant differences on mean rooting percentage, mean root development, mean root weight, mean number of root, mean shoot weight and mean shoot+root weight.

  11. From phenology models to risk indicator analysis

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    Márta Ladányi

    2010-11-01

    Full Text Available In this paper we outline a phenology model for estimating budbreak and full bloom starting dates of sour cherry on the effective heat sums with reasonable accuracy. With the help of RegCM3.1 model the possible trends of the phenology timing in the middle of the 21st century the shift of 12-13 days earlier budbreak and 6-7 days earlier of full bloom due to the warmer weather conditions can be clearly indicated. For the climatic characterization of sour cherry bloom period in between 1984-2010 and for the description of the expected changes in this very sensitive period of sour cherry withrespect to the time slice 2021-2050, we introduce seven climatic indicators as artificial weather parameters such as the numbers of days when the temperature was under 0°C and above 10 °C, the numbers of days when there was no and more than 5 mm precipitation as well as the absolute minimum, the mean of minimum and the mean of maximum daily temperatures. We survey the changes of the indicators in the examined period (1984-2010 and, regarding the full bloom start model results, we formulate the expectations forthe future and make comparisons.

  12. Climate Change and Crop Exposure to Adverse Weather: Changes to Frost Risk and Grapevine Flowering Conditions.

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    Jonathan R Mosedale

    Full Text Available The cultivation of grapevines in the UK and many other cool climate regions is expected to benefit from the higher growing season temperatures predicted under future climate scenarios. Yet the effects of climate change on the risk of adverse weather conditions or events at key stages of crop development are not always captured by aggregated measures of seasonal or yearly climates, or by downscaling techniques that assume climate variability will remain unchanged under future scenarios. Using fine resolution projections of future climate scenarios for south-west England and grapevine phenology models we explore how risks to cool-climate vineyard harvests vary under future climate conditions. Results indicate that the risk of adverse conditions during flowering declines under all future climate scenarios. In contrast, the risk of late spring frosts increases under many future climate projections due to advancement in the timing of budbreak. Estimates of frost risk, however, were highly sensitive to the choice of phenology model, and future frost exposure declined when budbreak was calculated using models that included a winter chill requirement for dormancy break. The lack of robust phenological models is a major source of uncertainty concerning the impacts of future climate change on the development of cool-climate viticulture in historically marginal climatic regions.

  13. Compounds Derived from Garlic as Bud Induction Agents in Organic Farming of Table Grape Compuestos Derivados de Ajo como Agentes Inductores de Brotación en Cultivo Orgánico de Uva de Mesa

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    Irasema Vargas-Arispuro

    2008-03-01

    Full Text Available Viticulture is one of the most important economic activities in the Northwest of Mexico. A major obstacle for the economic production is the insufficient period of chilling temperatures. This problem leads to poor budbreak, which in turn results in reduced yields. This problem is aggravated when plants are cultivated using the organic farming system, mostly because there are not organically approved restbreaking agents. In this work different products derived from garlic (Allium sativum L. were obtained and evaluated as stimulate budbreak agent of table grape (Vitis vinifera L. cvs. Flame Seedless and Perlette. The isolated compounds were chemically identified and include allicin, diallyl disulfide, diallyl trisulfide, 3-vynil-[4H]-1,2-ditiin and 2-vynil-[3H]-1,3-ditiin, S-methyl cysteine sulphoxide, dimethyl disulfide, dimethyl trisulfide and dimethyl thiosulfonate. Cuttings with six buds were used to evaluate the compounds. After compounds were applied, the cuttings were transferred to a growing chamber at 24 °C. All evaluated compounds promoted budbreak in the cuttings of Flame Seedless and Perlette. The volatile compounds from S-methyl cysteine sulfoxide promoted 100% of budbreak of both cultivars. The compounds from garlic that stimulated budbreak in grapevines in this work include sulphur in their molecule; therefore we propose that sulphur could play a key role in breaking bud dormancy of grape cultivars evaluated in this studyLa viticultura es una de las principales actividades económicas en el Noroeste de México. Entre los problemas que enfrenta esta actividad está el período de frío insuficiente, lo que lleva a una pobre brotación y consecuentemente una menor producción. Este problema se agrava cuando se cultivan plantas por el método orgánico, ya que no existen agentes inductores de brotación aprobados para uso orgánico. En este trabajo se aislaron diferentes compuestos derivados de ajo (Allium sativum L. que se evaluaron

  14. Effects of Temperature and Several Chemicals on Metabolic Changes During Dormancy Release in NJ72 Nectarine

    Institute of Scientific and Technical Information of China (English)

    YUAN Zhi-you; LI Xian-li; LI Ling-hao; HAN Xing-guo; YAN Tian-li

    2003-01-01

    Poor, delayed and ununiform budbreak is a major problem for peaches in greenhouse. To clari-fy the mechanism of breaking bud dormancy in nectarines, the effect of temperature and three dormancy-breaking agents on metabolic changes during dormancy release in two-year old NJ72 nectarine (Prunus persicaL. Batch) was investigated. The result showed temperature and chemicals affected the budbreak and the me-tabolism of NJ72 nectarine during dormancy. Endogeneons peroxide content in buds increased soon after lowtemperature treatment. Meanwhile, catalase activity was also shown to increase significantly at low temperature treatment, coincided with increase of the activity of peroxidase and superoxide dismntase. The rate of res-piration in flower buds increased at low temperature during dormancy. The rate of the pentose phosphate path-way increased, while the rate of the Embden-Meyerhof pathway decreased and the rate of triearboxlic acid cycle changed little. Glucose 6-phosphate dehydrogenase activity increased at low temperature during dormancy.At the same time we found an accumulation of peroxide after treatment with dormancy-breaking chemicals. Inflower buds treated with dormancy-breaking agents, thiourca, KNO3 and NH4 NO3, catalase activity was in-hibited soon after treatment, whereas peroxidase activity increased, and the changes of superoxide dismutaseremained little. In this study, it was found that the rates of respiration in flower buds increased by chemicalssprays during dormancy. The activity of glucose 6-phosphate dehydrogenase, the key enzyme in the pentosephosphate pathway (PPP), increased by spraying with dormancy-breaking agents, concomitantly with the ac-tivatlon of the pentose phosphate pathway.

  15. Potential effect of atmospheric warming on grapevine phenology and post-harvest heat accumulation across a range of climates

    Science.gov (United States)

    Hall, Andrew; Mathews, Adam J.; Holzapfel, Bruno P.

    2016-09-01

    Carbohydrates are accumulated within the perennial structure of grapevines when their production exceeds the requirements of reproduction and growth. The period between harvest and leaf-fall (the post-harvest period) is a key period for carbohydrate accumulation in relatively warmer grape-growing regions. The level of carbohydrate reserves available for utilisation in the following season has an important effect on canopy growth and yield potential and is therefore an important consideration in vineyard management. In a warming climate, the post-harvest period is lengthening and becoming warmer, evidenced through studies in wine regions worldwide that have correlated recent air temperature increases with changing grapevine phenology. Budbreak, flowering, veraison, and harvest have all been observed to be occurring earlier than in previous decades. Additionally, the final stage of the grapevine phenological cycle, leaf-fall, occurs later. This study explored the potential for increased post-harvest carbohydrate accumulation by modelling heat accumulation following harvest dates for the recent climate (1975-2004) and two warmer climate projections with mean temperature anomalies of +1.26 and +2.61 °C. Summaries of post-harvest heat accumulation between harvest and leaf-fall were produced for each of Australia's Geographical Indications (wine regions) to provide comparisons from the base temperatures to projected warmer conditions across a range of climates. The results indicate that for warmer conditions, all regions observe earlier occurring budbreak and harvest as well as increasing post-harvest growing degree days accumulation before leaf-fall. The level of increase varies depending upon starting climatic condition, with cooler regions experiencing the greatest change.

  16. Adaptation of lodgepole pine and interior spruce to climate: implications for reforestation in a warming world.

    Science.gov (United States)

    Liepe, Katharina J; Hamann, Andreas; Smets, Pia; Fitzpatrick, Connor R; Aitken, Sally N

    2016-02-01

    We investigated adaptation to climate in populations of two widespread tree species across a range of contrasting environments in western Canada. In a series of common garden experiments, bud phenology, cold hardiness, and seedling growth traits were assessed for 254 populations in the interior spruce complex (Picea glauca, P. engelmannii, and their hybrids) and for 281 populations of lodgepole pine (Pinus contorta). Complex multitrait adaptations to different ecological regions such as boreal, montane, coastal, and arid environments accounted for 15-20% of the total variance. This population differentiation could be directly linked to climate variables through multivariate regression tree analysis. Our results suggest that adaptation to climate does not always correspond linearly to temperature gradients. For example, opposite trait values (e.g., early versus late budbreak) may be found in response to apparently similar cold environments (e.g., boreal and montane). Climate change adaptation strategies may therefore not always be possible through a simple shift of seed sources along environmental gradients. For the two species in this study, we identified a relatively small number of uniquely adapted populations (11 for interior spruce and nine for lodgepole pine) that may be used to manage adaptive variation under current and expected future climates.

  17. Cutaneous reactions simulating erythema multiforme and Stevens Johnson syndrome due to occupational exposure to a plant-growth regulator

    Directory of Open Access Journals (Sweden)

    Inamadar Arun

    2007-01-01

    Full Text Available Background: In India, hydrogen cyanamide (Dormex ® is a plant growth regulator used mainly for the bud-breaking of grapevines. The use of this chemical may result in severe cutaneous reactions simulating erythema multiforme (EM, Stevens-Johnson syndrome (SJS and toxic epidermal necrolysis (TEN. Methods: Studies were conducted on four seasonal grapevine workers who developed severe cutaneous reactions following the unprotected use of Dormex ® (hydrogen cyanamide. Results: Two of the patients had EM-like skin lesions and the other two developed SJS-TEN-like skin lesions. A latent period of 5-7 days existed between the contact with the chemical and the development of the skin lesions. The histopathological picture was suggestive of EM. All the patients responded to systemic steroids and antihistamines. Conclusions: Hydrogen cyanamide may act as a hapten, initiating cytotoxic immunological attack on keratinocytes, resulting in EM- and SJS-TEN-like clinical picture. Awareness regarding such severe cutaneous reactions due to the inappropriate handling of Dormex ® is required. The use of personal protection equipments while handling agricultural chemicals is essential.

  18. Homologs of FT, CEN and FD respond to developmental and environmental signals affecting growth and flowering in the perennial vine kiwifruit.

    Science.gov (United States)

    Varkonyi-Gasic, Erika; Moss, Sarah M A; Voogd, Charlotte; Wang, Tianchi; Putterill, Joanna; Hellens, Roger P

    2013-05-01

    FLOWERING LOCUS T (FT) and CENTRORADIALIS (CEN) homologs have been implicated in regulation of growth, determinacy and flowering. The roles of kiwifruit FT and CEN were explored using a combination of expression analysis, protein interactions, response to temperature in high-chill and low-chill kiwifruit cultivars and ectopic expression in Arabidopsis and Actinidia. The expression and activity of FT was opposite from that of CEN and incorporated an interaction with a FLOWERING LOCUS D (FD)-like bZIP transcription factor. Accumulation of FT transcript was associated with plant maturity and particular stages of leaf, flower and fruit development, but could be detected irrespective of the flowering process and failed to induce precocious flowering in transgenic kiwifruit. Instead, transgenic plants demonstrated reduced growth and survival rate. Accumulation of FT transcript was detected in dormant buds and stem in response to winter chilling. In contrast, FD in buds was reduced by exposure to cold. CEN transcript accumulated in developing latent buds, but declined before the onset of dormancy and delayed flowering when ectopically expressed in kiwifruit. Our results suggest roles for FT, CEN and FD in integration of developmental and environmental cues that affect dormancy, budbreak and flowering in kiwifruit.

  19. Adaptation of lodgepole pine and interior spruce to climate: implications for reforestation in a warming world.

    Science.gov (United States)

    Liepe, Katharina J; Hamann, Andreas; Smets, Pia; Fitzpatrick, Connor R; Aitken, Sally N

    2016-02-01

    We investigated adaptation to climate in populations of two widespread tree species across a range of contrasting environments in western Canada. In a series of common garden experiments, bud phenology, cold hardiness, and seedling growth traits were assessed for 254 populations in the interior spruce complex (Picea glauca, P. engelmannii, and their hybrids) and for 281 populations of lodgepole pine (Pinus contorta). Complex multitrait adaptations to different ecological regions such as boreal, montane, coastal, and arid environments accounted for 15-20% of the total variance. This population differentiation could be directly linked to climate variables through multivariate regression tree analysis. Our results suggest that adaptation to climate does not always correspond linearly to temperature gradients. For example, opposite trait values (e.g., early versus late budbreak) may be found in response to apparently similar cold environments (e.g., boreal and montane). Climate change adaptation strategies may therefore not always be possible through a simple shift of seed sources along environmental gradients. For the two species in this study, we identified a relatively small number of uniquely adapted populations (11 for interior spruce and nine for lodgepole pine) that may be used to manage adaptive variation under current and expected future climates. PMID:26834833

  20. Effects of elevated ozone on CO2 uptake and leaf structure in sugar maple under two light environments

    International Nuclear Information System (INIS)

    The interactive effects of ozone and light on leaf structure, carbon dioxide uptake and short-term carbon allocation of sugar maple (Acer saccharum Marsh.) seedlings were examined using gas exchange measurements and 14C-macroautoradiographic techniques. Two-year-old sugar maple seedlings were fumigated from budbreak for 5 months with ambient or 3 × ambient ozone in open-top chambers, receiving either 35% (high light) or 15% (low light) of full sunlight. Ozone accelerated leaf senescence, and reduced net photosynthesis, 14CO2 uptake and stomatal conductance, with the effects being most pronounced under low light. The proportion of intercellular space increased in leaves of seedlings grown under elevated ozone and low light, possibly enhancing the susceptibility of mesophyll cells to ozone by increasing the cumulative dose per mesophyll cell. Indeed, damage to spongy mesophyll cells in the elevated ozone × low light treatment was especially frequent. 14C macroautoradioraphy revealed heterogeneous uptake of 14CO2 in well defined areole regions, suggesting patchy stomatal behaviour in all treatments. However, in seedlings grown under elevated ozone and low light, the highest 14CO2 uptake occurred along larger veins, while interveinal regions exhibited little or no uptake. Although visible symptoms of ozone injury were not apparent in these seedlings, the cellular damage, reduced photosynthetic rates and reduced whole-leaf chlorophyll levels corroborate the visual scaling of whole-plant senescence, suggesting that the ozone × low light treatment accelerated senescence or senescence-like injury in sugar maple. (author)

  1. Modeling olive-crop forecasting in Tunisia

    Science.gov (United States)

    Ben Dhiab, Ali; Ben Mimoun, Mehdi; Oteros, Jose; Garcia-Mozo, Herminia; Domínguez-Vilches, Eugenio; Galán, Carmen; Abichou, Mounir; Msallem, Monji

    2016-01-01

    Tunisia is the world's second largest olive oil-producing region after the European Union. This paper reports on the use of models to forecast local olive crops, using data for Tunisia's five main olive-producing areas: Mornag, Jemmel, Menzel Mhiri, Chaal, and Zarzis. Airborne pollen counts were monitored over the period 1993-2011 using a Cour trap. Forecasting models were constructed using agricultural data (harvest size in tonnes of fruit/year) and data for several weather-related and phenoclimatic variables (rainfall, humidity, temperature, Growing Degree Days, and Chilling). Analysis of these data revealed that the amount of airborne pollen emitted over the pollen season as a whole (i.e., the Pollen Index) was the variable most influencing harvest size. Findings for all local models also indicated that the amount, timing, and distribution of rainfall (except during blooming) had a positive impact on final olive harvests. Air temperature also influenced final crop yield in three study provinces (Menzel Mhiri, Chaal, and Zarzis), but with varying consequences: in the model constructed for Chaal, cumulative maximum temperature from budbreak to start of flowering contributed positively to yield; in the Menzel Mhiri model, cumulative average temperatures during fruit development had a positive impact on output; in Zarzis, by contrast, cumulative maximum temperature during the period prior to flowering negatively influenced final crop yield. Data for agricultural and phenoclimatic variables can be used to construct valid models to predict annual variability in local olive-crop yields; here, models displayed an accuracy of 98, 93, 92, 91, and 88 % for Zarzis, Mornag, Jemmel, Chaal, and Menzel Mhiri, respectively.

  2. Detritivores enhance the mobilization of 137Cs from leaf-litter

    International Nuclear Information System (INIS)

    A large amount of radioactive material was released from the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident after the disastrous earthquake and subsequent tsunami of March 2011. Since most of the Japanese land area is covered by forest ecosystems, 137Cs was mostly deposited and accumulated on the land surface of forest. The fate of radioactive materials accumulated on the leaf litters should be conscientiously monitored to understand the future distribution and the spread to the surrounding landscapes. Because the accident took place on 11 March 2011, just before the bud-break of deciduous trees, the 137Cs are highly accumulated on the surface of leaf litter on the forest floor. This accumulated 137Cs had transferred to higher trophic organisms mainly through the detritus food chain. However, on the litter surface, 137Cs considered to be strongly and immediately fixed and highly immobilized. Decomposition processes in the forest floor can re-mobilise the nutritional elements which are contained within detritus and make them available for the organisms. In the present study, the feeding effect of detritivore soil arthropods on the mobilization of 137Cs from leaf litter was experimentally examined. Furthermore, the effect of detritivores on the plant uptake of 137Cs was examined by small-scale nursery experiment. Decomposition experiment in the small microcosms was performed using a larvae of Trypoxylus dichotomus, whichis a detritivores feeding on dead plant materials such as wood debris and leaf litters. Contaminated leaf litters were collected in a forest of the Kami-Oguni River catchment in the northern part of Fukushima Prefecture. The leaf litters at A0 layers which are highly contaminated by 137Cs were utilized for the experiment. The contaminated leaf litter was fed to the larvae for ten days. The litter with larvae excreta was washed by 2 M KCl and deionized water. The 137Cs concentration was measured by germanium detectors (Seiko EG and G). As a

  3. Seleção de genótipos de pessegueiro F1 com baixa necessidade de frio hibernal Selection of F1 peach genotypes with low chilling requirements

    Directory of Open Access Journals (Sweden)

    Américo Wagner Júnior

    2009-12-01

    Full Text Available A baixa necessidade de frio é característica fundamental para que se possa cultivar economicamente o pessegueiro em condições de clima subtropical, devendo ser este, portanto, o principal objetivo dos programas de melhoramento nestas regiões. o objetivo deste trabalho foi avaliar e selecionar progênies de pessegueiro com baixa necessidade de frio hibernal por meio do método de ramos destacados e indicar o melhor genitor para utilização em programas de melhoramento, visando a esta característica. Foram avaliados 180 genótipos pertencentes a 25 populações de pessegueiro, sendo que o número de genótipos em cada população variou de três a dezenove. os ramos foram submetidos a 50; 100; 150; 200 e 400 unidades de frio, e, ao término de cada tratamento, os ramos foram transferidos para o interior da casa de vegetação. Após 21 dias, foram avaliados quanto às porcentagens de floração e brotação,e com os resultados obtidos, 5 populações e 29 genótipos de pessegueiro com baixa necessidade de frio hibernal foram selecionados. A cultivar Real mostrou-se eficiente na obtenção de pessegueiros com baixa necessidade de frio hibernal, quando utilizada como genitor feminino.Low chilling requirement is the main characteristic for the economic cultivation of peaches under subtropical climate conditions, therefore it should be the most important objective in breeding programs for these regions. The aim of this work was to evaluate and to select peach progenies with low chilling requirement through detached twigs methodology, to indicate a good genitor for using in the breeding program with this characteristic. A total of 180 genotypes, from 25 peach populations, were observed. The genotypes of each population varied from three to nineteen plants. The twigs were submitted to 50, 100, 150, 200 and 400 chilly units. once the treatments were concluded, the twigs were transferred to a greenhouse and after twenty one days the budbreak and

  4. Detritivores enhance the mobilization of {sup 137}Cs from leaf-litter

    Energy Technology Data Exchange (ETDEWEB)

    Murakami, Masashi; Suzuki, Takahiro [Community Ecology Lab., Biology Course, Faculty of Science, Chiba University, Chiba, 263-8522 (Japan); Ishii, Nobuyoshi [National Institute of Radiological Sciences, Chiba, 263-8555 (Japan); Ohte, Nobuhito [Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, 113-8657 (Japan)

    2014-07-01

    A large amount of radioactive material was released from the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident after the disastrous earthquake and subsequent tsunami of March 2011. Since most of the Japanese land area is covered by forest ecosystems, {sup 137}Cs was mostly deposited and accumulated on the land surface of forest. The fate of radioactive materials accumulated on the leaf litters should be conscientiously monitored to understand the future distribution and the spread to the surrounding landscapes. Because the accident took place on 11 March 2011, just before the bud-break of deciduous trees, the {sup 137}Cs are highly accumulated on the surface of leaf litter on the forest floor. This accumulated {sup 137}Cs had transferred to higher trophic organisms mainly through the detritus food chain. However, on the litter surface, {sup 137}Cs considered to be strongly and immediately fixed and highly immobilized. Decomposition processes in the forest floor can re-mobilise the nutritional elements which are contained within detritus and make them available for the organisms. In the present study, the feeding effect of detritivore soil arthropods on the mobilization of {sup 137}Cs from leaf litter was experimentally examined. Furthermore, the effect of detritivores on the plant uptake of {sup 137}Cs was examined by small-scale nursery experiment. Decomposition experiment in the small microcosms was performed using a larvae of Trypoxylus dichotomus, whichis a detritivores feeding on dead plant materials such as wood debris and leaf litters. Contaminated leaf litters were collected in a forest of the Kami-Oguni River catchment in the northern part of Fukushima Prefecture. The leaf litters at A0 layers which are highly contaminated by {sup 137}Cs were utilized for the experiment. The contaminated leaf litter was fed to the larvae for ten days. The litter with larvae excreta was washed by 2 M KCl and deionized water. The {sup 137}Cs concentration was measured

  5. Effects of different spacing between the inner and outer membrane on temperature, grapevine growth and fruit set in greenhouse with double-film%双膜间距对大棚栽培葡萄棚温及生长坐果的影响

    Institute of Scientific and Technical Information of China (English)

    何风杰; 何桂娥; 徐小菊; 金伟; 陈青英; 江海娥

    2015-01-01

    The effects of different spacing between the inner and outer membrane on the temperature, growth and fruit set of 5-year-old Fujiminori grapevine in greenhouse with double-film were studied. The result showed that:with the increase of distance between the inner and outer membrane, the effect of temperature rise and accumulated temperature in greenhouse were better. Compared with 40 cm and 20 cm treatments, the daily average temperature of 60 cm treatment was increased by 0.77 ℃ and 1.67 ℃ respectively, and the accumulated temperature increased by 73.6 ℃ and 158.5 ℃. In 60 cm treatment, the phenological phases such as budbreak and mature period were ahead of schedule, and the harvest was advanced to May 6th, respectively 4 d and 8d earlier compared with 40 cm and 20 cm treatments, so the benefits were significantly improved correspondingly. However, the germination rate, fruit-setting rate, fruit firmness, color, soluble solids content and other quality indicators of 40 cm treatment were the highest in all treatments. Therefore, the spacing of double-film culture take 40~60 cm as proper.%以5年生藤稔葡萄为试材,研究了内外膜不同间距对双膜大棚葡萄棚内温度及生长、坐果的影响。试验结果表明:随着内外膜间距的增加,棚内温度的提升和积温增加效果更好,间距60 cm的日均温度比40 cm和20 cm分别提高0.77℃、1.67℃,积温分别增加73.6℃和158.5℃,萌芽期、成熟期也更早。内外膜60 cm间距的大棚葡萄在5月6日上市,较40 cm和20 cm间距的葡萄分别提早上市4 d和8 d,种植效益也有明显增加;棚膜40 cm间距的葡萄其萌芽率、坐果率、粒质量、可溶性固形物含量及着色度等指标均为各处理最高,综合品质最好。故双膜栽培的内外膜间距以40~60 cm为宜。

  6. Atividade de enzimas relacionadas com a mobilização de carboidratos durante a dormência da nogueira (Juglans Regia Walnut enzyme activity related with carbohydrate mobilization during dormancy period

    Directory of Open Access Journals (Sweden)

    Idemir Citadin

    2009-06-01

    Full Text Available A brotação da nogueira é dependente da mobilização de carboidratos do lenho para as gemas localizadas na porção superior dos ramos. O objetivo do trabalho foi contribuir para o entendimento do mecanismo de brotação acrótona da nogueira, em clima temperado, através da mensuração da atividade da ±-amilase (EC 3.2.1.1 e sacarose fosfato sintase (SPS - EC 2.4.1.14 relacionadas com a mobilização de carboidratos, durante o período de dormência. Para cada coleta, foram amostrados cinco ramos do ano, durante os meses de setembro a março. Em abril, próximo à retomada do crescimento ativo, foram feitas três amostragens. As partes apical, subapical e da base dos ramos foram separadas em casca, lenho (xilema e gemas. O tempo médio de brotação (TMB em condições controladas (25ºC, a umidade ponderal e a atividade das enzimas acima relacionadas foram determinadas. Os resultados obtidos reforçam a teoria de que o gradiente de brotação na nogueira se desenvolve durante a ecodormência e apresenta uma relação de dependência com a atividade da á-amilase; não está evidente a relação da atividade da SPS com a evolução do crescimento das gemas, durante a ecodormência.Juglans regia L. sprout depends on the carbohydrate mobilization from the parenchyma cells into the buds located in the upper portion of the twigs. The objective of this work was to contribute to the walnut tree sprout acrotony mechanism, in temperate climate, through the activity of alpha-amylase (EC 3.2.1.1, and Sucrose Phosphate Synthase (SPS - EC 2.4.1.14 mensuration, related to carbohydrate mobilization, during the dormancy period. From September to March, five one-year-old twigs were monthly sampled around. In April, close to budbreak, three samples were accomplished. The twigs were divided in apical, sub-apical, and base, and separated in bark, buds and wood (xylem. The average time of bud break in controlled conditions (25ºC, water content, and activity