The Interaction of (2-Chloroethyl) trimethylammonium Chloride and Gibberellic Acid in Strawberry

Applications of (2-chloroethyl) trimethylammonium chloride (CCC), by foliar spray or to the soil, shortened petioles and decreased top and root growth of strawberry plants. Application of gibberellic acid increased petiole length and fresh weights of tops but not of roots. Applied together gibberellic acid overcame the depression of growth in weight of tops induced by CCC and countered the depression in petiole lengths. Gibberellic acid induced elongation of internodes of the vegetative stem and the elongation was increased substantially by concurrent application of CCC. This synergism in stem growth indicates a lack of antagonism between CCC and exogenous gibberellic acid in strawberry. The implications are discussed.     

Growth, Sex Expression and Yield of Squash Melon (Citrullus vulgarisvar. fistulosus) as Influenced by 2(chloroethyl)phosphonic acid, 2,3,5-tri-iodobenzoic acid and (2-chloroethyl) trimethyl-ammonium chloride

Single aqueous sprays of 2(chloroethyl)phosphonic acid (CEPA) 250, 500 and 1000 mg/1; 2,3,5-triiodobenzoic acid (TIBA) 25, 50 and 100 mg/1; and (2-chloroethyl) trimethyl-ammonium chloride (CCC) 250, 500 and 1000 mg/1 were applied to squash melon (Citrullus vulgaris Schrad. var. fistu-losus Stocks.) at the 2–3 leaf stage. Though the final length of the main axis and number of lateral branches were not affected by any treatment, CEPA retarded growth of young plants by reducing the internodal length. It did not change the flowering pattern but delayed flowering and reduced the production of both pistillate and staminate flowers. However, it increased the per cent femaleness as a result of comparatively more suppression of staminate flowers. The TIBA 25 and 50 mg/1 and CCC 500 mg/1 did not affect the staminate flower production but increased the pistillate flowers, which increased the per cent femaleness. The CEPA decreased while both TIBA 25 and 50 mg/1, and CCC 500 mg/1 increased the number of fruits per plant and the yield. The mode of action of the chemicals has been discussed.     

Pigment Changes Associated with Application of Ethephon ((2-Chloroethyl)phosphonic Acid) to Fig (Ficus carica L.) Fruits

The application of (2-chloroethyl)phosphonic acid (Ethephon) to `Mission' fig fruits (Ficus carica L.) during late period II of their development stimulated ripening and change in color from green to bluish black within 8 days. Chlorophylls a and b decreased rapidly within 4 days after Ethephon treatment, and degradation continued at a decreasing rate for an additional 4 days, at which time the fruits had attained their maximum diameter and were considered fully ripe. Levels of β-carotene, lutein, violaxanthin, and neoxanthin decreased in a pattern similar to that of chlorophylls a and b. The rates of β-carotene and lutein degradation were initially greater than those of the xanthophyll pigments. Degradation rates of the various carotenoids were comparable 4 to 8 days after treatment.     

Total and Polar Lipid Biosynthesis during Crotalaria juncea Linn. Pollen Tube Growth: Effect of Gibberellic Acid, Indoleacetic Acid and (2-Chloroethyl)-phosphonic Acid

Gibberellic acid (GA₃) at 58 µM, indoleacetic acid (IAA)at 29 µM, and (2-chloroethyl) phosphonic acid (Ethephon)at 70 µM promoted pollen tube growth in Crotalaria junceapollen suspension cultures both in water and basal medium. GA₃stimulated [ l-¹⁴C]acetate incorporation into total lipids inboth media, whereas IAA enhanced incorporation in water culturesonly. On the contrary, Ethephon reduced the label in total lipidswhen supplemented in basal medium. Based on [l-¹⁴C lacetateincorporation into different phospho- and glycolipids, it isproposed that these growth regulators have a definite role inthe biosynthesis of lipid components of the membranes.     

Effects of Gibberellic Acid, Benzyladenine and 2-Chloroethylphosphonic acid (CEPA) on Growth and Fruit Abscission in the Cowpea (Vigna unguiculata L.)

Cowpea cultivars, Adzuki, Ife Brown and New Era, were raisedin a pot-soil experiment, under greenhouse conditions. Whenapplied as a foliar spray, none of the three growth regulators,gibberellic acid (GA), benzyladenine (BA) and 2-chloroethylphosphonicacid (CEPA), had any significant effects on the vegetative growthof either Adzuki or Ife Brown, CEPA, however, suppressed stemelongation and root dry weight, and also caused defoliation,in New Era. GA had no significant effect on fertility (defined as the proportionof the number of floral buds to those developing into mature,functional, seed-bearing pods). GA also had no significant effecton harvest index (expressed as the percentage of whole plantdry weight represented by seed dry weight) in the three cultivars.BA suppressed fertility in both Ife Brown and New Era, but hadno influence on Adzuki. CEPA was effective in controlling abscission in cowpea by reducingthe number of floral buds initiated, but enhancing the numberof functional pods set, in New Era. CEPA also enhanced harvestindex in this cultivar by increasing the absolute seed weightwithout affecting total plant dry weight. The implications ofthese observations on the physiology of the cultivars are discussedin relation to the problem of fruit abscission in the cowpeaplant. Vigna unguiculata L., cowpea, abscission, gibberellic acid, benzyladenine, 2-chloroethylphosphonic acid     

Effect of Gibberellic Acid, (2-Chloroethyl) Phosphonic Acid, Actinomycin-D and Cycloheximide on the Activity and Leaching of Some Hydrolases in Pollen Suspension Cultures of Crotalaria juncea

Gibberellic acid (GA₃) 20 mg 1^?1 and (2-chloroethyl) phosphonic acid (Ethephon) 10 mg 1^?1 enhanced pollen tube length in Crotalaria juncea L. GA₃ markedly increased the activity of amylase, acid phosphatase and β-glucosidase and enhanced leaching of amylase and acid phosphatase enzymes. The rise in the activity level and leaching of amylase and acid phosphatase after Ethephon treatment was comparatively less than that of GA₃ and the response to Ethephon was restricted to the 45 and 90 min period of culturing. Ethephon did not affect the activity/leaching of β-glucosidase significantly. Actinomycin-D (Act.D) 25 mg l^?1 and Cycloheximide (CH) 10 mg 1^?1 reduced the tube growth as well as activity of these enzymes suggesting their de novo synthesis during pollen tube growth.     

Effects of Temperature and Photoperiod on Growth and Development of Tillers and Rhizomes in Poa pratensis L. Ecotypes

The vegetative growth of four Norwegian ecotypes of Poa pratensisL. was compared at day/night temperatures of 21/12, 21/6, 12/12and 12/6 °C and at photoperiods of 12, 16, 20 and 24 h,the irradiation being approximately equal in all treatments.Tillering within tufts was most abundant in short days and atthe large temperature amplitude. Rhizome formation and elongationwere stimulated by long days and, more strongly, by high daytemperature, but a greater proportion of the rhizomes formedaerial tillers in short days. Long day stimulation of heightgrowth and dry matter accumulation differed between ecotypesbut was generally most pronounced at low temperatures. The NorthNorwegian ecotype ‘Lavang’ had a higher relativegrowth rate and developed two to three times as many rhizomesas its South Norwegian counterparts. Day/night temperature, growth rate, leaf area, photoperiodicity, Poa pratensis L., rhizomes, roots, smooth meadow grass, tillering, weight gain     

The Effects of N-1-Naphthylphthalamic Acid and (2-Chloroethyl)-phosphonic Acid on the Gravity-induced Lateral Transport of 2, 4-Dichlorophenoxyacetic Acid

N-1-Naphthylphthalamic acid markedly reduced the polar lateralmovement of 2, 4-D-[1-¹⁴C] induced by gravity in horizontalsegments of Helianthus hypocotyl. The pattern of this inhibitionresembled the inhibition of basipetal polar transport, suggestingthat both polar movements are operated by essentially the samephysiological mechanisms though there are indications of sensitivitydifferences between the two systems. Ethrel pretreatment of segments, though inhibiting the basipetaltransport of 2, 4-D by 33 per cent over the concentration range0.2 to 2.0 per cent, has little significant effect on gravity-inducedlateral polarity of movement, suggesting that ethylene doesnot act directly on the auxin transport system.     

Effects of 2-Chloroethyl Trimethylammonium Chloride (CCC) and 2-Chloroethylphosphonic Acid (CEPA) on Dry Matter Distribution in the Cowpea (Vigna Unguiculata L.)

Effects of foliar applications of CCC and CEPA on dry matterdistribution in two cowpea cultivars which exhibit differentdegrees of premature abscission of fruits were investigated.At the concentration of 0-1 mg1^–1, CCC increased stemweight in the cultivar Adzuki, but had no effect on the cv.Mala (which exhibits a relatively high degree of premature abscission).While CCC did not significantly influence root weight in Adzuki,the concentrations of 1 and 10 mg 1^–1 increased root weightin Mala. In both cultivars, the 1000 mg1^–1 treatment decreasedseed weight, with a greater decrease in Adzuki. All concentrations of CEPA, up to 1000 mg 1^–1, decreasedstem and root weights in Mala, and leaf weight in Adzuki. The10 mg1^–1 concentration increased seed weight in Mala by100 percent, and leaf weight by 28 percent, without any significanteffect on pod weight, or on the weight of the whole plant. Therewas also no increase in pod number. Overall, Mala was more responsive than Adzuki to the growthregulators, particularly CEPA. In the low concentration responses,CEPA increased seed weight not by increasing gross plant weight,but mainly by causing a change in distribution of dry matter.     

Microbial hydroxylation of (+/-)- and (-)-(2Z,4E)-5-(1',2'-epoxy-2',6',6'-trimethylcyclohexyl)-3-methyl-2,4-pentadienoic acid into (+/-)- and (-)-xanthoxin acid by Cunninghamella echinulata

Microbial hydroxylation of (+/-)-(2Z,4E)-5-(1',2'-epoxy-2',6',6'-trimethylcyclohexyl)-3-methyl-2,4-pentadienoic acid (3a) with Cercospora cruenta, a fungus producing (+)-abscisic acid, gave a four-stereoisomeric mixture consisting of (+)- and (-)-xanthoxin acid (4a), and (+)- and (-)-epi-xanthoxin acid (5a) by an HPLC analysis with a chiral column. Screening of the microorganisms capable of oxidizing (+/-)-3a showed that Cunninghamella echinulata stereoselectively oxidized (+/-)-3a to xanthoxin acid (4a) with the some degree of enantioselectivity as (-)-3a to (-)-4a.     

芦丁对绿豆幼苗营养生长的影响及其与IAA的相互作用

观察了植物体内的天然黄酮芦丁和吲哚乙酸(IAA)对绿豆幼苗营养生长的影响并测定胚轴中的芦丁和IAA含量.光照条件下芦丁(60μg/mL以下)处理对绿豆幼苗生长有一定促进作用,表现为胚轴和主根伸长加快、侧根数目增多、鲜重或干重增加;而光照条件下更高浓度芦丁(80μg/mL以上)处理及黑暗条件下芦丁(20～100μg/mL)处理对绿豆幼苗生长有抑制作用.当培养基中的芦丁浓度为60～80 μg/mL时,光照下的幼苗比暗处理的幼苗在胚轴中积累更多的芦丁;而芦丁浓度为40μg/mL以下和接近100μg/mL时幼苗在光照下累积的芦丁较暗处理的幼苗更少.0.1μg/mL以上的IAA促进芦丁的累积而进一步抑制幼苗胚轴和主根的伸长.当培养基中含有40 μg/mL的芦丁和0.5μg/mL的IAA时,胚轴中累积的芦丁达到高峰.芦丁降低黄化幼苗内源性IAA在胚轴中的累积,并抑制幼苗对IAA的吸收.     

Changes in the phenolic metabolism of suspension cultures of Acer pseudoplatanus L. Caused by the addition of 2-(chloroethyl)phosphonic acid (CEPA)

Summary 2-(Chloroethyl)phosphonic acid (CEPA) inhibited the rise in tannin production and phenylalanine ammonia-lyase EC 4.1.1.5 (PAL) activity shown by Acer cells in media containing 9.0×10^–7 M 2,4-D for a period of 2–3 days after its addtion.Abbreviation 2,4-D 2,4-dichlorophenoxyacetic acid     

Effects of elevated CO2 and nitrogen on growth ofPoa pratensis (L.)

The growth responses of a grass,Poa pratensis, to elevated CO₂ and nitrogen were investigated. Light-saturated photosynthetic rate per unit leaf area increased with exposure to elevated CO₂, while dry weight did not respond to increased CO₂. Patterns of biomass allocation within plants, including leaf area, leaf area ratio, specific leaf area, and root to shoot ratios, were not altered by elevated CO₂, but changed considerably with N treatment Shoot and whole-plant tissue N concentrations were significantly diluted by elevated CO₂ (Tukey test, P < 0.05). Total N content did not differ significantly among CO₂ treatments. The absence of a concomitant increase in N uptake under elevated CO₂ may have caused a dilution in plant tissue [N], probably negating the positive effects of increased photosynthesis on biomass accumulation.     

Syntheses of (Z)-and (E)-4-amino-2-(trifluoromethyl)-2-butenoic acid and their inactivation of gamma-aminobutyric acid aminotransferase.

(Z)- and (E)-4-amino-2-(trifluoromethyl)-2-butenoic acid (4 and 5, respectively) were synthesized and investigated as potential mechanism-based inactivators of gamma-aminobutyric acid aminotransferase (GABA-AT) in a continuing effort to map the active site of this enzyme. The core alpha-trifluoromethyl-alpha,beta-unsaturated ester moiety was prepared via a Reformatsky/reductive elimination coupling of the key intermediates tert-butyl 2,2-dichloro-3,3,3-trifluoropropionate and N,N-bis(tert-butoxy-carbonyl)glycinal. Both 4 and 5 inhibited GABA-AT in a time-dependent manner, but displayed non-pseudo-first-order inactivation kinetics; initially, the inactivation rate increased with time. Further investigation demonstrated that the actual inactivator is generated enzymatically from 4 or 5. This inactivating species is released from the active site prior to inactivation, and as a result, 4 and 5 cannot be defined as mechanism-based inactivators. Furthermore, 4 and 5 are alternate substrates for GABA-AT, transaminated by the enzyme with Km values of 0.74 and 20.5 mM, respectively. Transamination occurs approximately 276 and 305 times per inactivation event for 4 and 5, respectively. The enzyme also catalyzes the elimination of the fluoride ion from 4 and 5. A mechanism to account for these observations is proposed.     

Interaction of staphylococcal penicillinase and 6-[D(-)-alphaguanidino-phenylacetamido]-penicillanic acid

6[d(-)-alpha-Guanidinophenylacetamido]-penicillanic acid was shown to be significantly hydrolyzed by only one of six preparations of staphylococcal penicillinase. This penicillin analogue is a stronger penicillinase inactivator than are nafcillin and methicillin, which were not significantly hydrolyzed by the enzyme.