Tulip Research Articles

Allergic contact dermatitis to tulips: an example of enantiospecificity.

Allergic contact dermatitis (ACD), an immunological reaction of the skin resulting from contact with reactive compounds occurring in plants was shown to the enantiospecific (animals sensitized to a compound do not react to its nonsuperimposable mirror image). Thus, when guinea pigs were experimentally sensitized to (+)-tulipalin B (a compound present in tulip bulbs) they did not react to its enantiomer, (-)-tulipalin B. This was also true for (+)- and (-)-beta-hydroxy-gamma-methyl-alpha-methylene-gamma-butyrolactones.

Variation in the development of stem nematodes, Ditylenchus dipsaci, in susceptible and resistant crop plants

SUMMARYDicotyledonous plants were reliably inoculated with stem nematodes by placing drops of 1.3% carboxymethylcellulose containing the surface sterilised worms between the cotyledons or in the leaf axils of recently emerged seedlings raised in pots of cool, moist soil. Inoculating onion leaves, bean stems and potato tubers or potato leaves gave variable results and inoculating onion, tulip and narcissus bulbs and lucerne and red clover stems was usually unsuccessful. An attempt to characterise 67 stem nematode populations by the reactions of a number of different plants failed for lack of useful differential hosts. Lucerne was, however, resistant to all but lucerne populations.Multiplication of stem nematode populations varied greatly between cultivars of lucerne or red clover. Some cultivars were resistant to some populations of lucerne or red clover stem nematodes and susceptible to others. These differences could not be ascribed to differences in viability of the nematodes or to differences in success of the inoculations. They indicate the presence of different pathotypes or biotypes in different populations of a so‐called ‘host race’ and indicate the need for new resistant cultivars to be tested against a range of populations before they are released for general use. Amongst lucerne cultivars tested, Vertus was resistant to some lucerne stem nematode populations and susceptible to others. The supposedly resistant lucerne cultivars Euver and Lifeuil were as susceptible as was Europe. Amongst red clover cultivars tested, Redhead, Kühn, Changins and Mt Calme were susceptible, Britta, Lucrum and Temara were the least resistant, Renova, Rittinova and Quin were intermediate and susceptible to one or more of the populations tested but Norseman and especially Sabtoron were very resistant.

Rhizoctonia tuliparum . [Distribution map

Abstract A new distribution map is provided for Rhizoctonia tuliparum Whetzel & J. M. Arthur. Hosts: Tulip, Iris and other ornamental bulbs and corms. Information is given on the geographical distribution in EUROPE, Austria, Denmark, Finland, Germany, Iceland, Netherlands, Romania, Switzerland, UK, USSR (Moscow district), (Sverdlovsk region), Yugoslavia, NORTH AMERICA, Canada (Ontario), (British Columbia), USA, (Yonkers, New York), (Washington State).

A new agglutinin from the Tulipa gesneriana bulbs.

Two agglutinins with different agglutinating activity exist in Tulipa gesneriana bulbs. One is the T. gesneriana lectin which agglutinates yeasts as reported previously [Oda, Y. and Minami, K. (1986) Eur. J. Biochem. 159, 239-245]. The other agglutinin is a new one which agglutinates animal erythrocytes and was purified from the tulip bulbs using affinity chromatography on thyroglobulin-Sepharose 4B. The agglutinin agglutinated mouse and rat erythrocytes at a minimum concentration of 2 micrograms/ml and 30 micrograms/ml respectively, but did not agglutinate erythrocytes from other animals and yeasts even at a concentration of 1000 micrograms/ml. The agglutinin appeared homogeneous by disc gel electrophoresis at pH 4.3 and gel filtration. Its relative molecular mass was determined by gel filtration to be approximately 40,000. It was suggested that the agglutinin was composed of two different subunits of 26 kDa and 14 kDa by sodium dodecyl sulfate/polyacrylamide gel electrophoresis analysis. Binding of radioiodinated agglutinin to mouse erythrocytes indicated that the presence of a high-affinity site with a dissociation constant of 2.00 X 10(-9) M. In inhibition experiments thyroglobulin glycopeptides were the most potent inhibitors; thyroglobulin was also a potent inhibitor. Orosomucoid and mucin showed weak inhibition. The other glycoproteins, glycopeptides and sugars examined showed no inhibition.

Interaction of azole derivatives with cytochrome P‐450 isozymes in yeast, fungi, plants and mammalian cells

AbstractYeast and plant membranes contain rather small amounts of cytochrome P–450 as compared with membrane fractions prepared from bovine adrenal cortex, piglet testis and rabbit liver.The agricultural fungicides azaconazole, penconazole, propiconazole and imazalil showed a much greater affinity for microsomal cytochrome P–450 isozymes of Saccharomyces cerevisiae and Candida albicans (ATCC 28516) than for cytochrome P–450 in microsomal fractions prepared from Jerusalem artichoke tubers, maize shoots, pea seedlings or tulip bulbs and for cytochrome P–450 isozymes in mitochondrial or microsomal fractions from rabbit liver, piglet testis and bovine adrenals. The medicinal azole antifungals miconazole, clotrimazole, ketoconazole, fluconazole and itraconazole also interacted at much lower concentrations with the microsomal cytochrome P–450 isozymes from S. cerevisiae and C. albicans (ATCC‐28516, ATCC 44859, B 34226/1) than with those in mammalian membranes. Itraconazole showed the highest selectivity; bifonazole was much less selective.The microsomal fraction prepared from C. albicans (isolate B 41628) contained cytochrome P–450 isozymes with a lower affinity than the microsomal fractions from other isolates for miconazole, ketoconazole, fluconazole and itraconazole. However, itraconazole showed still high affinity for these cytochrome P–450 isozymes. In animal models this C. albicans isolate was less pathogenic and was shown to be less sensitive to azole antifungals both in vitro and in vivo.Azole antifungals inhibited ergosterol synthesis at nanomolar concentrations whereas almost micromolor concentrations were needed to obtain a similar inhibition of cholesterol or phytosterol synthesis. This inhibition coincided with the accumulation of 14α‐methylsterols such as 14‐methyl‐fecosterol, 14‐methyl‐24‐methylene‐ergosterol, 14‐methyl‐ergosta‐8, 24 (28)‐dien‐3β, 6α‐diol, obtusifoliol, lanosterol and 24‐methylenedihydro‐lanosterol. In 24‐h‐old cultures of C. albicans the 3β, 6α‐diol was the major sterol. It is speculated that by making the 14α‐methylsterols less lipophilic the cells are trying to eliminate these membrane‐disturbing compounds. This suggests that the azole‐induced ergosterol depletion might represent a greater contribution to their fungicidal activity than the accumulation of 14α‐methylsterols.

Fungicidal Control of Infection by Penicillium spp. of Precooled Tulip Bulbs in a Modified Atmosphere Package

Fungicidal Control of Infection by Penicillium spp. of Precooled Tulip Bulbs in a Modified Atmosphere Package

The Annual Time Budget of the Farmer's Family Producing Tulip Bulbs

The Annual Time Budget of the Farmer's Family Producing Tulip Bulbs

The Annual Time Budget of the Farmer's Family Producing Tulip Bulbs (I)

The Annual Time Budget of the Farmer's Family Producing Tulip Bulbs (I)

A new lectin from tulip (Tulipa) bulbs

A lectin was isolated from tulip (Tulipa) bulbs by affinity chromatography on fetuin-agarose and partially characterized. The tulip lectin is a tetrameric protein composed of four identical subunits of Mr 28 000, which are not held together by disulphide bonds. It is not glycosylated and has an amino-acid composition typified by a high content of asparagine-aspartic acid, leucine, glycine and serine. Tulip lectin agglutinates human red blood cells, but has a much higher specific activity with rabbit erythrocytes. In hapten-inhibition assays with the latter type of red blood cell the lectin exhibits a complex specificity, whereas its agglutination with human erythrocytes is readily inhibited by N-acetylgalactosamine, lactose, fucose and galactose.

Bulb Organ Changes and Influence of Temperature on Gaseous Levels in a Modified Atmosphere Package of Precooled Tulip Bulbs

Abstract Modified atmosphere (MA) packages of tulip bulbs (Tulipa gesneriana L. ‘Kees Nelis’) composed of 5 bulbs sealed in low-density polyethylene film (LDF-301, Dow Chemical) were exposed to 20°C for one week followed by 3 weeks of temperature regimes between 15° and 25°. The temperature changes resulted in little change in package CO2 and O2 equilibrium levels. Bulbs held in air flowered poorly after 3 or 4 weeks at most of the temperature regimes. Packaged bulbs held below 25°C yielded 80–100% normal flowers after 3 or 4 weeks storage. The dry weight (DW) of daughter bulbs within bulbs in air increased 7-fold during 4 weeks storage. These bulbs also lost 25% of total bulb DW, 35% of scale DW, and 20% of floral shoot DW. There was little daughter bulb enlargement and few significant changes in DW of other bulb organs in film-packaged bulbs during storage.

Isolation and characterization of a lectin from tulip bulbs, Tulipa gesneriana.

A lectin, which agglutinated specifically the yeast cells of the Saccharomyces genus, was isolated from tulip bulbs (Tulipa gesneriana) using affinity chromatography on mannan-Sepharose 4B. Its relative molecular mass was determined by gel filtration to be approximately 67,000. On polyacrylamide gel electrophoresis in sodium dodecyl sulfate, a relative molecular mass of 17,000 was obtained, suggesting that the lectin is a tetramer. Binding studies performed with iodinated lectin indicated that Saccharomyces cerevisiae cells contained approximately 5.7 X 10(6) binding sites per cell, whereas little binding was observed with yeasts other than the Saccharomyces genus, bacteria and animal erythrocytes. D-Mannose, D-mannose 6-phosphate, L-fucose and L-fucosylamine were potent inhibitors of the lectin binding to S. cerevisiae cells, while, D-glucose, D-galactose and D-mannosamine were inactive, indicating that hydroxyl group at C-2 of D-mannose was essential for the lectin binding. Furthermore, inhibition experiments, using various manno-oligosaccharides, suggested that the lectin recognized (1----6)-linked manno-oligosaccharide units larger than mannobiose.

Countryside Going Past

Cowboys and Indians Picture remembered: my mother, in pin-curled hair, tall like shadows in a valley, stands on the back porch holding the threadspool handle of the wooden screen door in one hand, hurling, with the other, one dish after another at my father's taunting face. No sound remembered. Just his laughing face and the dishes sailing smooth like horseshoes in a friendly game until they shatter in the rock pile. Angry clatter. I'm drawn back by sun and shadow and the bloom of rose of Sharon to my waiting place, hiding from my outlaw brother in the gorge below. My tobacco stick horse bears rough saw ridges, swirls, and long strawy filaments of unraveled baling twine, his rein. The flower at eye level is pink and white, a droopy, velvety, deep-dish tulip flower, hidden among rough, serrated leaves, seen clearly. —Carolyn Reams Smith Countryside Going Past Jewelweed in the ditch Goldenrod blooming by the road Double yellow line House hazed in fog Mailbox with its flag down Curve that's hard to take Barn Pond Stop sign You don't want to know where I'm going. You don't get an explanation. Highway leading to the next county Entry ramp onto the freeway Pavement going to the city. —Nancy Simpson To Bixby Creek Again and to You, Raccoon Shocked awake by the half-nail moon jabbing deep into the canyon. So bright I felt an unnamed fear in my gut. Fell back to sleep as the moon traced the sky. Woke again near dawn to your perfect footprint on the misted window— like burning lace. Thanks again, masked partner and fellow poet for sharing in the night's crime, whatever it was. And let's not let those bastards catch us. —William Witherup 59 ...

'Een merkwaardige verzameling Teekeningen' door Leonaert Bramer

'Een merkwaardige verzameling Teekeningen' door Leonaert Bramer

チューリップ花茎の節間伸長に及ぼす光条件の影響と内生ジベレリンの変化

Changes in endogenous gibberellins in the first and upper internodes of tulip were investigated under light and dark growing conditions. In darkness, the elongation of the first internode was increased. The level of polar, free gibberellin also increased, while the level of the bound form decreased. Under natural light, a rapid increase in the length of the last internode was parallelled by an increase in non-polar free gibberellin. It is suggested that two different gibberellins are involved in controlling the elongation of the lower and upper internodes of tulip flower stalk. An interconversion system between free and bound forms of polar and non-polar gibberellins, which act in the first and the upper internodes respectively, and the dependence of these upon light conditions were also suggested.

Control of stem nematode, Ditylenchus dipsaci, in tulip bulbs with aldicarb and oxamyl

In the Netherlands complete elimination of the stem nematode Ditylenchus dipsaci (Kühn, Filipjev) in tulip by destruction of infested lots and sterilization of infested soil is the aim of the Plant Protection Service. Elimination of stem nematode in narcissus bulbs is achieved by hot-water treatment, but this treatment is not appropriate for tulip bulbs because these are damaged at temperatures of 43 · 5°C and higher. As the effects of the systemic nematicides aldicarb and oxamyl looked promising, these were investigated further. Aldicarb, 6 kg a.i./ha, was applied once in the autumn and once in spring. Oxamyl, 2 · 88 kg a.i./ha, was applied three times in spring. The efficacy of these nematicides was shown not only by a reduction in the numbers of infested bulbs but also by a reduction in nematode numbers in the bulbs, shown here in the frequency distribution of infested bulbs over nematode numbers. However in some bulbs, probably those which had the highest number of nematodes before planting, a few stem nematodes could still be detected, having survived high dosages of nematicides. Therefore, complete elimination of stem nematodes from infected bulbs with very high nematode numbers is probably impossible. It is expected, however, that repeated treatment will increase the percentage of nematode-free bulbs and will lead to almost healthy tulip-bulb stocks.

Determination of the Structure of Oligofructan in the Tulip Bulb

Some species of plants which belong to Asterales, Poales (Graminales), Liliales, Asparagas, and others contain fructan as a reserve carbohydrate (1). Three types of fructosylsucroses, isokestose (l-kestose, 1F-β-fructosylsucrose), kestose (6-kestose, 6F-β-fructosylsucrose), and neokestose (6G-β-fructosylsucrose) are key intermediates for the related highly polymerized oIigofructans (1, 2). Inulin is a higher homologous oligosaccharide of isokestose whose fructofuranosyl residues are (2-+1)-β-linked, and phlein (or levan) is a higher homologue based on the kestose whose fructosyl residues are joined by a (2→6)-β-linkage. Furthermore, there are also highly polymerized oligofructans related to neokestose. In the members of Liliales, all ,three types of fructans have been found (1). As for the tulip bulb, HAMMER investigated the trisaccharide from two species of tulips (Tulipa silvestris L. and Tulipa clusiana), and the results showed that the tulip bulb appeared to contain mainly isokestose together with tra...

Starch content of freeze-dried anthers and α-amylase activity of their extracts as criteria that dry-stored bulbs ( Tulipa gesneriana, L.) cultivar ‘Apeldoorn’ have been exposed to 5°C

Starch and sucrose were estimated selectively in freeze-dried anthers from tulip bulbs pre-cooled at 5°C for 12 weeks and from a control batch maintained at 17°C. α-Amylase activity in anther extracts was also estimated. Based on data from our own trials (1981, 1982 and 1983) and from 18 batches from typical bulb-producing regions in The Netherlands (year 1983), sucrose was discarded as indicator. The following tentative criteria are proposed for detecting whether dry bulbs cultivar ‘Apeldoorn’ have been exposed to 5°C: starch content of freeze-dried anthers should exceed 10% and specific activity of α-amylase should be below 0.16 (arbitrary unit per mg protein). These criteria are not indicative of the duration of the 5°C period.

Changes in Endogenous Gibberellin and Auxin Activities during First Internode Elongation in Tulip Flower Stalk

Changes in Endogenous Gibberellin and Auxin Activities during First Internode Elongation in Tulip Flower Stalk

Purification of a single major form of microsomal cytochrome P-450 from tulip bulbs (Tulipa gesneriana L.).

Microsomal cytochrome P-450 from tulip bulbs (Tulipa gesneriana L., Balalaika) was purified to an almost electrophoretically homogeneous preparation. The specific content of cytochrome P-450 in the final preparation was 6.68 nmol/mg protein, which was 30-fold enriched from that of the solubilized fractions of microsomes. The molecular weight of purified cytochrome P-450 by SDS-gel electrophoresis is 52,500. The Oxidized form of the purified cytochrome P-450 had absorption peaks at 392, 552, and 645 nm and the absolute reduced CO spectrum peaked at 448 nm. Judged spectrally, the purified cytochrome P-450 is in high spin in the oxidized state. Antiserum against this cytochrome P-450 previously has shown to be highly specific for its antigen but showed a single precipitin line with solubilized microsomal proteins from tulip bulbs of several other cultivars. The physiological role of this cytochrome P-450, however, is unknown in these dormant tulip bulbs.

Responses of potted tulips to novel growth-retarding chemicals and interactions with time of forcing

The effects of the growth retardants ancymidol and 2,3-dihydro-5,6-diphenyl-1,4-oxathiin (coded UBI-P293) were compared on early-, mid- and late-season forced tulip bulbs of cultivars ‘Apeldoorn’, ‘Paul Richter’ and ‘Rose Copland’. The chemicals were applied as single soil drenches, 1 day after transferring plants to the glasshouse. These treatments did not affect flower or petal length nor delay flowering, but high concentrations resulted in increased floral bud blasting in early-season ‘Apeldoorn’ (with ancymidol only) and in early- and mid-season ‘Rose Copland’ (with UBI-P293 only). Both ancymidol and UBI-P293 effectively dwarfed plants of all 3 cultivars at each time of forcing, provided sufficiently high concentrations were selected. However, early- and mid-season ‘Apeldoorn’ plants were particularly responsive to these compounds, the highest doses of which resulted in reductions in stem length at flowering of 70–80% (for ancymidol) or 50–60% (for UBI-P293); similar doses achieved less dwarfing in ‘Paul Richter’ and ‘Rose Copland’ and in late-season ‘Apeldoorn’. In ‘Apeldoorn’ and ‘Paul Richter’, ancymidol reduced extension markedly in the first internode, with less effect distally; UBI-P293 was effective in reducing extension of all internodes. Compost drenches of 3 newer growth retardants were also evaluated. Mepiquat chloride had no effect on flowering except that floral bud blasting was increased in ‘Rose Copland’. The stem responses of ‘Paul Richter’ and ‘Rose Copland’ to mepiquat chloride were trivial, but in ‘Apeldoorn’ the highest dose tested (2500 mg a.i./pot) reduced overall stem length via an effect on first internode extension. A quaternary sulphonium carbamate (coded BTS 44 584) had no effects on flowering or stem extension at concentrations up to 2500 mg a.i./pot. An N-carbamoylimidazole (coded BTS 34 723), tested at 1–50 mg a.i./pot, had small effects on internode extension which depended on cultivar, but potentially useful dwarfing was not observed.