The Experts below are selected from a list of 231 Experts worldwide ranked by ideXlab platform
Rebecca L. Darnell - One of the best experts on this subject based on the ideXlab platform.
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Inflorescence Bud Initiation, Development, and Bloom in Two Southern Highbush Blueberry Cultivars
Journal of the American Society for Horticultural Science, 2015Co-Authors: Alisson P. Kovaleski, Jeffrey G. Williamson, James W. Olmstead, Rebecca L. DarnellAbstract:ADDITIONAL INDEX WORDS. floral development, floral Initiation, growing degree days, reproductive Buds, Vaccinium corymbosum ABSTRACT. Blueberry (Vaccinium spp.) production is increasing worldwide, particularly in subtropical growing regions,butinformationontimingandextentofinflorescence Buddevelopmentduringsummerandfallandeffectson bloom the next season are limited. The objectives of this study were to determine time of inflorescence Bud Initiation, describe internal inflorescence Bud development, and determine the relationship between internal inflorescence Bud development and bloom period the next spring in two southern highbush blueberry (SHB (Vaccinium corymbosum interspecific hybrids)) cultivars. 'Emerald' and 'Jewel' SHB Buds were collected beginning in late summer until shoot growth cessation in late fall for dissection and identification of organ development. Inflorescence Bud frequency and number, vegetative and inflorescence Bud length and width throughout development, and bloom were also assessed. InflorescenceBud Initiation occurred earlier in'Emerald' compared with'Jewel'.Fivestages ofinternal inflorescence Bud development were defined throughout fall in both cultivars, ranging from a vegetative meristem to early expansion of the inflorescence Bud in late fall. 'Emerald' inflorescence Buds were larger and bloomed earlier, reflecting the earlier inflorescence Bud Initiation and development. Although inflorescence Bud Initiation occurred earlierin'Emerald'comparedwith'Jewel',thepatternofdevelopmentwasnotdifferent.TimingofinflorescenceBud Initiation influenced timing of bloom with earlier Initiation resulting in earlier bloom.
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Photoperiod and temperature effects on growth and carbohydrate storage in southern highbush blueberry interspecific hybrid
Journal of the American Society for Horticultural Science, 2004Co-Authors: Timothy M. Spann, Jeffrey G. Williamson, Rebecca L. DarnellAbstract:ADDITIONAL INDEX WORDS. daylength, fl ower Bud Initiation, fl ower development ABSTRACT. Experiments were conducted with 'Mistyʼ southern highbush blueberry (Vaccinium corymbosum L. interspecifi c hybrid) to test the effects of high temperature on fl ower Bud Initiation and carbohydrate accumulation and partitioning. Plants were grown under inductive short days (SDs = 8 hour photoperiod) or noninductive SDs with night interrupt (SD- NI = 8 hour photoperiod + 1 hour night interrupt), at either 21 or 28 oC for either 4 or 8 weeks. Flower Bud Initiation occurred only in the inductive SD treatments and was signifi cantly reduced at 28 oC compared with 21 °C. The number of fl ower Buds initiated was not signifi cantly different between 4- and 8-week durations within the inductive SD, 21 oC treatment. However, fl oral differentiation appeared to be incomplete in the 4-week duration Buds and bloom was delayed and reduced. Although plant carbohydrate status was not associated with differences in fl ower Bud Initiation between SD and SD-NI treatments, within SD plants, decreased fl ower Bud Initiation at high temperature was correlated with decreased whole-plant carbohydrate concentration. These data indicate that fl ower Bud Initiation in southern highbush blueberry is a SD/long night phytochrome-mediated response, and plant carbohydrate status plays little, if any, role in regulating Initiation under these experimental conditions.
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Photoperiodic Effects on Vegetative and Reproductive Growth of Vaccinium darrowi and V. corymbosum Interspecific Hybrids
HortScience, 2003Co-Authors: Timothy M. Spann, Jeffrey G. Williamson, Rebecca L. DarnellAbstract:Experiments were conducted with V. darrowi and two cultivars of southern highbush blueberry, 'Sharpblueʼ and 'Misty,ʼ to test whether V. darrowi and cultivars derived from it are photoperiodic with respect to fl ower Bud Initiation. Plants of each cultivar were grown under three different photoperiod treatments (long days (LD) = 16-hour photoperiod; short days (SD) = 8-hour photoperiod; and short days + night interrupt (SD-NI) = 8-hour photoperiod with 1-hour night interrupt) at constant 21 °C for 8 weeks. Vegetative growth was greatest in the LD plants of both cultivars. Flower Bud Initiation occurred only in the SD treatments, and the lack of fl ower Bud Initiation in the SD-NI treatment indicates that fl ower Bud Initiation is a phytochrome mediated response in Vaccinium. Previously initiated fl ower Buds on the V. darrowi plants developed and bloomed during the LD treatment, but bloom did not occur in the SD and SD-NI treatment plants until after those plants were moved to LD. These data indicate that fl ower Bud Initiation in both V. darrowi and southern highbush blueberry is photoperiodically sensitive, and is promoted by short days, while fl ower Bud development is enhanced under long days.
K. D. Odlum - One of the best experts on this subject based on the ideXlab platform.
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effect of short term storage of shoot tips from black spruce container seedlings on the estimation of Bud Initiation and needle primordia number
2016Co-Authors: C. W. G. Templeton, S. J. Colombo, K. D. OdlumAbstract:effect of short-Term storage of shoot tips from black spruce container seedlings on the estimation of Bud Initiation and Needle Primordia Number , effect of short-Term storage of shoot tips from black spruce container seedlings on the estimation o... , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی
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How to identify Bud Initiation and count needle primordia in first-year spruce seedlings
The Forestry Chronicle, 1993Co-Authors: C. W. G. Templeton, K. D. Odlum, Stephen J. ColomboAbstract:Bud Initiation and subsequent Bud development are key steps in the nursery production of first-year temperate spruce seedlings for reforestation. An understanding of the Bud Initiation and development processes and monitoring methods are of vital importance to both tree seedling nursery workers and foresters. A review of Bud morphology and the Bud development process is given for spruce seedlings. The equipment required and techniques used in the determination of Bud Initiation, and estimation of the number of needle primordia are presented. When properly applied, the examination of spruce Buds forms a cornerstone for successful nursery management using extended greenhouse culture. Key words: Bud Initiation, Bud morphology, Bud dissection, black spruce, Picea mariana, needle primordia, nursery management
Jeffrey G. Williamson - One of the best experts on this subject based on the ideXlab platform.
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Inflorescence Bud Initiation, Development, and Bloom in Two Southern Highbush Blueberry Cultivars
Journal of the American Society for Horticultural Science, 2015Co-Authors: Alisson P. Kovaleski, Jeffrey G. Williamson, James W. Olmstead, Rebecca L. DarnellAbstract:ADDITIONAL INDEX WORDS. floral development, floral Initiation, growing degree days, reproductive Buds, Vaccinium corymbosum ABSTRACT. Blueberry (Vaccinium spp.) production is increasing worldwide, particularly in subtropical growing regions,butinformationontimingandextentofinflorescence Buddevelopmentduringsummerandfallandeffectson bloom the next season are limited. The objectives of this study were to determine time of inflorescence Bud Initiation, describe internal inflorescence Bud development, and determine the relationship between internal inflorescence Bud development and bloom period the next spring in two southern highbush blueberry (SHB (Vaccinium corymbosum interspecific hybrids)) cultivars. 'Emerald' and 'Jewel' SHB Buds were collected beginning in late summer until shoot growth cessation in late fall for dissection and identification of organ development. Inflorescence Bud frequency and number, vegetative and inflorescence Bud length and width throughout development, and bloom were also assessed. InflorescenceBud Initiation occurred earlier in'Emerald' compared with'Jewel'.Fivestages ofinternal inflorescence Bud development were defined throughout fall in both cultivars, ranging from a vegetative meristem to early expansion of the inflorescence Bud in late fall. 'Emerald' inflorescence Buds were larger and bloomed earlier, reflecting the earlier inflorescence Bud Initiation and development. Although inflorescence Bud Initiation occurred earlierin'Emerald'comparedwith'Jewel',thepatternofdevelopmentwasnotdifferent.TimingofinflorescenceBud Initiation influenced timing of bloom with earlier Initiation resulting in earlier bloom.
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Photoperiod and temperature effects on growth and carbohydrate storage in southern highbush blueberry interspecific hybrid
Journal of the American Society for Horticultural Science, 2004Co-Authors: Timothy M. Spann, Jeffrey G. Williamson, Rebecca L. DarnellAbstract:ADDITIONAL INDEX WORDS. daylength, fl ower Bud Initiation, fl ower development ABSTRACT. Experiments were conducted with 'Mistyʼ southern highbush blueberry (Vaccinium corymbosum L. interspecifi c hybrid) to test the effects of high temperature on fl ower Bud Initiation and carbohydrate accumulation and partitioning. Plants were grown under inductive short days (SDs = 8 hour photoperiod) or noninductive SDs with night interrupt (SD- NI = 8 hour photoperiod + 1 hour night interrupt), at either 21 or 28 oC for either 4 or 8 weeks. Flower Bud Initiation occurred only in the inductive SD treatments and was signifi cantly reduced at 28 oC compared with 21 °C. The number of fl ower Buds initiated was not signifi cantly different between 4- and 8-week durations within the inductive SD, 21 oC treatment. However, fl oral differentiation appeared to be incomplete in the 4-week duration Buds and bloom was delayed and reduced. Although plant carbohydrate status was not associated with differences in fl ower Bud Initiation between SD and SD-NI treatments, within SD plants, decreased fl ower Bud Initiation at high temperature was correlated with decreased whole-plant carbohydrate concentration. These data indicate that fl ower Bud Initiation in southern highbush blueberry is a SD/long night phytochrome-mediated response, and plant carbohydrate status plays little, if any, role in regulating Initiation under these experimental conditions.
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Photoperiodic Effects on Vegetative and Reproductive Growth of Vaccinium darrowi and V. corymbosum Interspecific Hybrids
HortScience, 2003Co-Authors: Timothy M. Spann, Jeffrey G. Williamson, Rebecca L. DarnellAbstract:Experiments were conducted with V. darrowi and two cultivars of southern highbush blueberry, 'Sharpblueʼ and 'Misty,ʼ to test whether V. darrowi and cultivars derived from it are photoperiodic with respect to fl ower Bud Initiation. Plants of each cultivar were grown under three different photoperiod treatments (long days (LD) = 16-hour photoperiod; short days (SD) = 8-hour photoperiod; and short days + night interrupt (SD-NI) = 8-hour photoperiod with 1-hour night interrupt) at constant 21 °C for 8 weeks. Vegetative growth was greatest in the LD plants of both cultivars. Flower Bud Initiation occurred only in the SD treatments, and the lack of fl ower Bud Initiation in the SD-NI treatment indicates that fl ower Bud Initiation is a phytochrome mediated response in Vaccinium. Previously initiated fl ower Buds on the V. darrowi plants developed and bloomed during the LD treatment, but bloom did not occur in the SD and SD-NI treatment plants until after those plants were moved to LD. These data indicate that fl ower Bud Initiation in both V. darrowi and southern highbush blueberry is photoperiodically sensitive, and is promoted by short days, while fl ower Bud development is enhanced under long days.
C. W. G. Templeton - One of the best experts on this subject based on the ideXlab platform.
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effect of short term storage of shoot tips from black spruce container seedlings on the estimation of Bud Initiation and needle primordia number
2016Co-Authors: C. W. G. Templeton, S. J. Colombo, K. D. OdlumAbstract:effect of short-Term storage of shoot tips from black spruce container seedlings on the estimation of Bud Initiation and Needle Primordia Number , effect of short-Term storage of shoot tips from black spruce container seedlings on the estimation o... , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی
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How to identify Bud Initiation and count needle primordia in first-year spruce seedlings
The Forestry Chronicle, 1993Co-Authors: C. W. G. Templeton, K. D. Odlum, Stephen J. ColomboAbstract:Bud Initiation and subsequent Bud development are key steps in the nursery production of first-year temperate spruce seedlings for reforestation. An understanding of the Bud Initiation and development processes and monitoring methods are of vital importance to both tree seedling nursery workers and foresters. A review of Bud morphology and the Bud development process is given for spruce seedlings. The equipment required and techniques used in the determination of Bud Initiation, and estimation of the number of needle primordia are presented. When properly applied, the examination of spruce Buds forms a cornerstone for successful nursery management using extended greenhouse culture. Key words: Bud Initiation, Bud morphology, Bud dissection, black spruce, Picea mariana, needle primordia, nursery management
Gregg Duester - One of the best experts on this subject based on the ideXlab platform.
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retinoic acid synthesis controlled by raldh2 is required early for limb Bud Initiation and then later as a proximodistal signal during apical ectodermal ridge formation
Journal of Biological Chemistry, 2004Co-Authors: Felix A Mic, Ovidiu I Sirbu, Gregg DuesterAbstract:Abstract We present evidence for the existence of two phases of retinoic acid (RA) signaling required for vertebrate limb development. Limb RA synthesis is under the control of retinaldehyde dehydrogenase-2 (Raldh2) expressed in the lateral plate mesoderm, which generates a proximodistal RA signal during limb outgrowth. We report that Raldh2-/- embryos lack trunk mesodermal RA activity and fail to initiate forelimb development. This is associated with deficient expression of important limb determinants Tbx5, Meis2, and dHand needed to establish forelimb Bud Initiation, proximal identity, and the zone of polarizing activity (ZPA), respectively. Limb expression of these genes can be rescued by maternal RA treatment limited to embryonic day 8 (E8) during limb field establishment, but the mutant forelimbs obtained at E10 display a significant growth defect associated with a smaller apical ectodermal ridge (AER), referred to here as an apical ectodermal mound (AEM). In these RA-deficient forelimbs, a ZPA expressing Shh forms, but it is located distally adjacent to the Fgf8 expression domain in the AEM rather than posteriorly as is normal. AER formation in Raldh2-/- forelimbs is rescued by continuous RA treatment through E10, which restores RA to distal ectoderm fated to become the AER. Our findings indicate the existence of an early phase of RA signaling acting upstream of Tbx5, Meis2, and dHand, followed by a late phase of RA signaling needed to expand AER structure fully along the distal ectoderm. During ZPA formation, RA acts early to activate expression of dHand, but it is not required later for Shh activation.
