Chilling Enhances Cane Elongation and Flowering in Primocane-fruiting Blackberries

Root cuttings of A-1836, APF-13, and NC194 primocane-fruiting (PF) blackberry (Rubus subgenus Rubus) genotypes were dug from the field on 31 July 1997 and stored in plastic bags at 2 °C for 32 days. On 1 Sept. freshly dug root cuttings, along with the cold-treated ones, were planted in pots, which were kept in a lath house for 4 weeks and then moved to a heated greenhouse under natural daylength. Cold-treatment hastened emergence of all genotypes. Transition from vegetative to floral phase was first observed in cold-treated A-1836 and APF-13 at the fifth node, with floral appendages clearly evident in both genotypes at the seventh node 45 days after planting (DAP). Bloom started on 26 Nov. and 5 Dec. 1997 and the first fruits were picked on 10 and 25 Jan. 1998 in cold-treated APF-13 and A-1836, respectively. Plants of cold-treated NC194 and of all non-cold-treated genotypes remained stunted with rosetted leaves, showing no signs of floral initiation until 150 DAP. These findings show that exposure to chilling prior to shoot emergence greatly promotes flowering in PF blackberries, and may have application in greenhouse culture of blackberry.

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Enhancement of Floral Initiation and Bud Development by Chilling of Root Cuttings in Primocane-fruiting Blackberries

HortScience ◽

10.21273/hortsci.33.3.454d ◽

1998 ◽

Vol 33 (3) ◽

pp. 454d-454

Author(s):

Jose Lopez-Medina ◽

James N. Moore ◽

Kyung-S. Kim

Keyword(s):

Plant Material ◽

Growth Stage ◽

Early Spring ◽

Floral Initiation ◽

Flower Buds ◽

Plastic Bags ◽

Plant Emergence ◽

Temperature Exposure ◽

Low Temperature Exposure ◽

Shoot Emergence

In previous studies we found that primocane-fruiting blackberries (PFB) form flower buds soon after the plants start suckering from root cuttings collected in winter or early spring. Research was carried out to test if the same phenomenon holds true in summer-collected plant material. Root cuttings of A-1836, APF-13 and NC194 PFB were dug from the field on 31 July 1997 and stored in plastic bags at 2 °C for 32 days. On 1 Sept., freshly dug root cuttings along with the cold-treated ones were stuck in 3.8-L plastic pots, which were kept in a lath house for 4 weeks and then moved to a greenhouse under natural daylength. Significant differences occurred for plant emergence between chilled and non-chilled plants (16 days vs. 31 days, respectively). Transition from vegetative to floral phase was first observed in cold-treated A-1836 and APF-13 at five-node growth stage, with floral structures clearly evident in both selections at seven nodes of growth 45 days after planting. Chilled APF-13 and A-1836 started to bloom on 26 Nov. and 5 Dec., respectively. The first fruit of APF-13 were picked on 10 Jan. 1998. By this date, cold-treated NC194 and all non-cold-treated plants remained stunted with rosetted leaves, showing no signs of floral initiation. These findings present evidence that low-temperature exposure prior to shoot emergence greatly promotes flowering and fruiting in PFB. The results might have applicability in blackberry culture under greenhouse conditions.

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Effect of Extreme Temperature on Quantum Yield of Fluorescence and Membrane Leakage of the Canarian Endemic Pine (Pinus canariensis)

Zeitschrift für Naturforschung C ◽

10.1515/znc-1999-9-1010 ◽

1999 ◽

Vol 54 (9-10) ◽

pp. 681-687 ◽

Cited By ~ 5

Author(s):

Juliane Peters ◽

M. Soledad Jiménez ◽

Domingo Morales

Keyword(s):

Quantum Yield ◽

Electrolyte Leakage ◽

Cold Treatment ◽

Extreme Temperature ◽

Pinus Canariensis ◽

Closed Chamber ◽

Laurel Forest ◽

Membrane Leakage ◽

Plastic Bags ◽

Water Saturated

The effect of extreme temperature on the quantum yield of fluorescence and membrane leakage of Pinus canariensis growing in 5 stands at different altitudes and orientation in Tenerife (Canary Islands, Spain) was determined. Needles were collected from the field and transferred to the laboratory where they were kept in a closed chamber with water-saturated air overnight. Then they were exposed for 30 minutes in plastic bags in a water bath at temperature treatments with steps of 2K between 56 °C and -24 °C and the effect was determined immediately and 24 hours after the treatment by chlorophyll fluorescence and electrolyte leakage. Needles presented incipient damage at temperatures ranging from -5 to -10 °C depending on the altitude and orientation of the stand. The results were more evident when the measurements were done 24 hours after the cold treatment and values were consistent with the electrolyte leakage results. Different resistance to high temperature depending on the altitude and orientation was also found, varying the temperature for incipient damage from 42 to 44 °C detected with the fluorescence parameters but not with the leakage of electrolytes which was not found until 50 °C. The amplitude of thermal limits for photosynthetic efficiency alteration in needles of P. canariensis was relatively narrow and similar to that of evergreen Canarian laurel forest trees

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Aerated water soak increases red oak seed germination and seedling emergence

Canadian Journal of Forest Research ◽

10.1139/x91-175 ◽

1991 ◽

Vol 21 (8) ◽

pp. 1257-1261 ◽

Cited By ~ 1

Author(s):

Daniel K. Struve ◽

Martin F. Dress ◽

Mark A. Bennett

Keyword(s):

Seed Germination ◽

Seedling Emergence ◽

Red Oak ◽

Germination Capacity ◽

Greenhouse Study ◽

Plastic Bags ◽

Shoot Emergence ◽

Number Of Seeds

Red oak (Quercusrubra L.) acorns were collected from three trees in September, placed in plastic bags, and held at 2 °C for 150 days. Acorns were given 0-, 10-, or 14-day aerated water soaks before germination tests were conducted. Acorns from two trees, given a 14-day soak, had significantly higher germination capacity and uniformity than untreated acorns. In another test, acorns were given a 10-day aerated water soak treatment and returned to 2 °C for 30 and 60 days. After 30 days, treated acorns had superior germination compared with untreated acorns. After 60 days, there were no significant differences in germination between treated and untreated acorns. In a greenhouse study, acorns given an aerated water soak had higher shoot-emergence capacity than untreated acorns. However, the aerated water soak treatment did not increase seedling efficiency, the ratio between the number of plantable seedlings and the number of seeds sown.

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Floral Initiation and Development in Aquilegia

HortScience ◽

10.21273/hortsci.25.3.294 ◽

1990 ◽

Vol 25 (3) ◽

pp. 294-296 ◽

Cited By ~ 4

Author(s):

J.W. White ◽

H. Chen ◽

X. Zhang ◽

D.J. Beattie ◽

H. Grossman

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Diurnal Variation ◽

Apical Meristem ◽

Cold Treatment ◽

Floral Initiation ◽

Floral Buds ◽

Fluorescent Lamps ◽

Growth Room ◽

Scanning Electron

Floral initiation and development of greenhouse and growth room-grown Aquilegia × hybrida Sims cultivars were studied using a scanning electron microscope. All greenhouse-grown cultivars initiated floral buds before cold treatment, ≈ 5 months after sowing. Floral initiation occurred at the apical meristem and proceeded acropetally on an elongated conical axis in the sequence: sepals, petals, stamens, stamenodia, and carpels. In a second experiment, 13 Aquilegia cultivars, three of which had been used in the first experiment, were grown as seedlings in a growth room at 20C under an 8-, 12-, 16-, or 20-hr photoperiod, each totaling 10.2 mol·day-1·m-2 irradiance from cool-white fluorescent lamps. Here, floral initiation was absent even after 7 months from sowing, presumably because there was no diurnal variation in irradiance or temperature.

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Yellow Nutsedge Shoot Emergence and Tuber Longevity

Weed Science ◽

10.1017/s004317450003174x ◽

1973 ◽

Vol 21 (1) ◽

pp. 76-81 ◽

Cited By ~ 33

Author(s):

E. W. Stoller ◽

L. M. Wax

Keyword(s):

Soil Temperature ◽

Kinetic Analysis ◽

Minimum Temperature ◽

Half Life ◽

Cold Treatment ◽

Cyperus Esculentus ◽

Temperature Minimum ◽

Yellow Nutsedge ◽

Shoot Emergence ◽

Number Of Shoots

Tubers of yellow nutsedge (Cyperus esculentusL.) were buried in the field 2.5 to 30.5 cm below the surface in November 1969 and 1970 at Urbana, Illinois. In both years, shoots began to emerge the following May and continued emergence until July. Very few additional shoots emerged after July. Shoots emerged from less than 2% of the tubers buried at 2.5 cm; the maximum number of shoots emerged from tubers at the 10.2 and 20.3-cm depths. Tubers at the 2.5 and 5.1-cm depths were more susceptible to winterkill than tubers at lower levels, probably because of the differences in soil temperature at these levels during cold periods. Kinetic analysis of laboratory-determined tuber viability for periods up to 22 months revealed that the half-life was 4.4 and 5.7 months for tubers buried at 10.2 and 20.3 cm, respectively. The extrapolated minimum temperature required for initiation of tuber germination in the laboratory was 12 C. This temperature minimum could not readily be related to initial shoot emergence in the field. The temperature at which 50% of the tubers survived a cold treatment for 4 to 48 hr was −7 C.

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The cold treatment of steel

Journal of the Institution of Production Engineers ◽

10.1049/jipe.1949.0002 ◽

1949 ◽

Vol 28 (1) ◽

pp. 21

Author(s):

E.G. Thurlby

Keyword(s):

Cold Treatment

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Colchicine Uptake and Binding by Human Platelets

Thrombosis and Haemostasis ◽

10.1055/s-0038-1651471 ◽

1975 ◽

Vol 34 (03) ◽

pp. 780-794 ◽

Cited By ~ 4

Author(s):

Dianne M Kenney ◽

Francis C Chao ◽

James L Tullis ◽

Gail S Conneely

Keyword(s):

Time Dependence ◽

Incubation Period ◽

Binding Sites ◽

Silicone Oil ◽

Cold Treatment ◽

Human Platelets ◽

Temperature Dependent

SummaryThe uptake and binding of antimitotic alkaloid colchicine has been demonstrated in washed preparations of human platelets. A silicone oil technique was adapted so that both uptake and binding of 14C-colchicine were examined in the same platelet preparations. The time dependence and amount of colchicine taken up and bound by different platelet preparations during a 90 to 120 min incubation period were highly reproducible. Both colchicine uptake and binding by intact platelets, and colchicine binding by preparations of lysed platelets were specific and temperature dependent. Colchicine uptake was slowly reversible. Magnesium and GTP enhanced colchicine binding by lysed platelet preparations but calcium decreased binding.Exposure of platelets to either cold (4° C) or to thrombin, which disrupt platelet microtubules, produced significant increases in colchicine uptake and binding. The thrombin effect was maximal at 37° C and resulted in a greater increase in uptake and binding than that produced by either cold treatment alone or, by cold treatment followed by incubation with thrombin at 37° C. The amount of increase in uptake and binding produced by thrombin was independent of both thrombin (1–5 Units/109 platelets) and colchicine concentrations (1–50 × 10−6M).It is postulated that thrombin may initiate the formation, or make available, colchicine binding sites (microtubule subunits) within platelets.

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