DIFFERENTIAL DISPLAY OF GENES INDUCED BY LOW TEMPERATURE IN BULB FORMATION OF HYACINTH

Fall-planted garlic (Allium sativum L.) has a higher number of cloves per bulb and higher bulb yield than spring-planted garlic. Many garlic growers, however, plant their crops in the spring to avoid losses associated with winterkill. Pre-plant storage temperature of cloves affects bulbing and cloving of the subsequent crop. Studies were conducted to determine the optimum duration of pre-plant chilling (4 °C) treatment for enhanced cloving and increased bulb yield of three spring-planted garlic cultivars (an unnamed local selection, California Early and California Late). In a greenhouse study, California Early and California Late cloves were planted after receiving low-temperature treatments of 4 °C for 0 (control), 30, 45, 60 or 75 days, whereas, for field studies, cloves from greenhouse-grown bulbs of all three cultivars were planted, and chilling treatments were similar to those for the greenhouse study.Pre-plant chilling treatments of cloves produced significant increases in cloving and bulb yield for all cultivars. In general, chilling treatment periods exceeding 30 d (for field) and 45 d (for greenhouse) resulted in improved cloving in bulbs of all cultivars. Improved cloving resulted in a significant increase in both bulb diameter and bulb yield per plant, particularly in greenhouse-grown garlic. Pre-plant chilling was not a pre-requisite for bulb formation, but it was essential for cloving. In conclusion, results indicate that better cloving and bulb yields are obtained if cloves have been stored at 4 °C for 45–60 d prior to field and greenhouse planting, respectively. Key words: Allium sativum, bulbing, low temperature treatment

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Etude du bourgeonnement in vitro de l'écaille du bulbe de Tulipe

Canadian Journal of Botany ◽

10.1139/b79-248 ◽

1979 ◽

Vol 57 (19) ◽

pp. 1986-1993 ◽

Cited By ~ 4

Author(s):

Simonne Rivière ◽

Jean-François Muller

Keyword(s):

Low Temperature ◽

Vegetative Propagation ◽

Culture Period ◽

Bulb Formation ◽

Bud Initiation

Vegetative propagation of tulips in vitro, not performed until now, is obtained using as explants scales of daughter bulbs collected in winter. Twenty-five percent of these explants give rise to neoformed buds within 6 months. These buds evolve into bulbs which are able to develop in the soil. Their ontogeny is studied histologically, from the beginning of the culture to the neoformed bulb formation. A treatment with low temperature and darkness at the beginning of the culture period promotes an earlier bud initiation.

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SEARCH FOR THE GENES REGULATING BULB FORMATION IN LILIUM SPECIOSUM BY DIFFERENTIAL DISPLAY

Acta Horticulturae ◽

10.17660/actahortic.2005.673.80 ◽

2005 ◽

pp. 583-589 ◽

Cited By ~ 1

Author(s):

K. Maehara ◽

K. Li-Nagasuga ◽

H. Okubo

Keyword(s):

Differential Display ◽

Bulb Formation ◽

Lilium Speciosum

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Exsolution and inversion in pigeonite from the Whin Sill, Northern England

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109513 ◽

1978 ◽

Vol 36 (1) ◽

pp. 474-475

Author(s):

P.P.K. Smith

Keyword(s):

High Temperature ◽

Low Temperature ◽

Homogeneous Nucleation ◽

Silicate Mineral ◽

Antiphase Boundaries ◽

Two Phase ◽

Primitive Form ◽

The Core ◽

Nucleation Mechanisms ◽

And Inversion

Grains of pigeonite, a calcium-poor silicate mineral of the pyroxene group, from the Whin Sill dolerite have been ion-thinned and examined by TEM. The pigeonite is strongly zoned chemically from the composition Wo8En64FS28 in the core to Wo13En34FS53 at the rim. Two phase transformations have occurred during the cooling of this pigeonite:- exsolution of augite, a more calcic pyroxene, and inversion of the pigeonite from the high- temperature C face-centred form to the low-temperature primitive form, with the formation of antiphase boundaries (APB's). Different sequences of these exsolution and inversion reactions, together with different nucleation mechanisms of the augite, have created three distinct microstructures depending on the position in the grain.In the core of the grains small platelets of augite about 0.02μm thick have farmed parallel to the (001) plane (Fig. 1). These are thought to have exsolved by homogeneous nucleation. Subsequently the inversion of the pigeonite has led to the creation of APB's.

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Low temperature x-ray microanalysis of frozen-hydrated tobacco leaves

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111537 ◽

1984 ◽

Vol 42 ◽

pp. 284-285

Author(s):

S. Edith Taylor ◽

Patrick Echlin ◽

May McKoon ◽

Thomas L. Hayes

Keyword(s):

Low Temperature ◽

Lemna Minor ◽

Root Tips ◽

Tobacco Leaves ◽

X Ray ◽

Whole Cells ◽

Carbon Coated ◽

The Right ◽

Beam Currents ◽

The University

Low temperature x-ray microanalysis (LTXM) of solid biological materials has been documented for Lemna minor L. root tips. This discussion will be limited to a demonstration of LTXM for measuring relative elemental distributions of P,S,Cl and K species within whole cells of tobacco leaves.Mature Wisconsin-38 tobacco was grown in the greenhouse at the University of California, Berkeley and picked daily from the mid-stalk position (leaf #9). The tissue was excised from the right of the mid rib and rapidly frozen in liquid nitrogen slush. It was then placed into an Amray biochamber and maintained at 103K. Fracture faces of the tissue were prepared and carbon-coated in the biochamber. The prepared sample was transferred from the biochamber to the Amray 1000A SEM equipped with a cold stage to maintain low temperatures at 103K. Analyses were performed using a tungsten source with accelerating voltages of 17.5 to 20 KV and beam currents from 1-2nA.

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Bulk standards for low-temperature biological x-ray microanalysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111525 ◽

1984 ◽

Vol 42 ◽

pp. 282-283

Author(s):

P. Echlin ◽

M. McKoon ◽

E.S. Taylor ◽

C.E. Thomas ◽

K.L. Maloney ◽

...

Keyword(s):

Phase Separation ◽

Low Temperature ◽

Analytical Method ◽

Salt Solutions ◽

Absolute Concentration ◽

Cooling Process ◽

X Ray ◽

The Absolute ◽

Analytical Procedures ◽

Electrical Conductors

Although sections of frozen salt solutions have been used as standards for x-ray microanalysis, such solutions are less useful when analysed in the bulk form. They are poor thermal and electrical conductors and severe phase separation occurs during the cooling process. Following a suggestion by Whitecross et al we have made up a series of salt solutions containing a small amount of graphite to improve the sample conductivity. In addition, we have incorporated a polymer to ensure the formation of microcrystalline ice and a consequent homogenity of salt dispersion within the frozen matrix. The mixtures have been used to standardize the analytical procedures applied to frozen hydrated bulk specimens based on the peak/background analytical method and to measure the absolute concentration of elements in developing roots.

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Field ion microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100104236 ◽

1988 ◽

Vol 46 ◽

pp. 434-435

Author(s):

Gert Ehrlich

Keyword(s):

Low Temperature ◽

Sample Surface ◽

Low Pressure ◽

Radius Of Curvature ◽

Field Ion Microscopy ◽

Phosphor Screen ◽

Ion Microscopy ◽

Field Ion Microscope

The field ion microscope, devised by Erwin Muller in the 1950's, was the first instrument to depict the structure of surfaces in atomic detail. An FIM image of a (111) plane of tungsten (Fig.l) is typical of what can be done by this microscope: for this small plane, every atom, at a separation of 4.48Å from its neighbors in the plane, is revealed. The image of the plane is highly enlarged, as it is projected on a phosphor screen with a radius of curvature more than a million times that of the sample. Müller achieved the resolution necessary to reveal individual atoms by imaging with ions, accommodated to the object at a low temperature. The ions are created at the sample surface by ionization of an inert image gas (usually helium), present at a low pressure (< 1 mTorr). at fields on the order of 4V/Å.

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