Influence Of Kinetin Research Articles

Influence of kinetin on storage protein mobilization and ultrastructure of plastids in excised lupine cotyledons grown in darkness

Storage protein disappeared first from the peripheral and later from central parts of the lupine cotyledon. Kinetin (500 μM) stimulated this process; its effect was most prominent after longer times of incubation. In plastids large, crystalline prolamellar bodies were observed. They some-times split into smaller parts during the course of the experiment, especially in the kinetin-treated material. Kinetin in darkness did not stimulate formation of thylakoid membranes (neither grana nor primary lamellae).

Cytochemical localization of peroxidase activity in the protonema of the moss Ceratodon purpureus during differentiation of gametophore buds induced by kinetin

An increase in the activity of peroxidases under the influence of kinetin has been demonstrated in the protonema of the moss <i>Ceratodon purpureus</i>. It was connected above all with initiation and acceleration of the differentiation process of gametophore buds which showed a high activity of these enzymes. The increase in peroxidase activity was also noted in the degenerating intercalary cells which produced the buds. The colour reaction characteristic for peroxidases was best noticeable in the minute spherical granules (peroxysomes), nucleoli and cell walls.

The Effect of Exogenous Phytohormones on Resistance of Wheat Calluses to <i>Tilletia caries</i> (D.C.) Tul. & C. Tul.

The influence of exogenic hormones (indole-3-acetic acid (IAA), abscisic acid (ABA) and kinetin) on defense reaction of wheat (Triticum aestivum L.) calli to the bunt agent Tilletia caries (D.C.) Tul. & C. Tul. was studied. ABA and kinetin induced the oxalate oxidase activity, increased the Н2О2 level, decreased germination of fungi teliospores and induced on calli the occurrence of dense sites non-infected by pathogen. On the contrary, IAA led to the decrease of oxalate oxidase activity, loosening of calli and increase germination of bunt agent teliospores and growth of fungi mycelium, besides stimulated rhizoids formation of wheat calli. Probably, the accumulation of Н2О2 in wheat calli under the influence of kinetin and ABA connected with activity of oxalate oxidase is one of the factors increasing defense reaction of wheat to bunt agent.

The influence of kinetin on regeneration of the protonema from isolated protoplasts of the moss Funaria hygrometrica L. Sibth

No stimulating effect of kinetin was noted on formation of the cell wall surrounding isolated protoplasts of the moss <em>Funaria hygrometrica</em>, although kinetin at a concentration of 1µM distinctly accelerated division of cells obtained from protoplasts and stimulated formation of the protonema and gametophores. At higher kinetin concentrations (5 µM) protoplasts, and later cells, increased their volume, whereas regeneration processes took place considerably more slowly than in the control.

Influence of kinetin on in vitro rooting and survival of banj oak (Quercus leucotrichophora L.)

A study concerning the influence of cytokinins on shoot regeneration by using different stem segments derived from in vitro raised seedlings and their subsequent rooting was conducted in banj oak (Quercus leucotrichophora L.). Cytokinins play an important role in shoot regeneration and their multiplication. In the present study, cytokinins particularly kinetin (Kn) influenced in vitro rooting and subsequent survival of these in vitro raised plants in addition to shoot multiplication. It was found that the microshoots raised via kinetin treatment rooted very well (94.44%) without any basal callus formation in comparison to microshoots raised via other cytokinin treatments (that is, BA and 2-iP). In addition to this, these in vitro raised plants showed maximum survival rate (90%) during hardening process. On the basis of available literature this is a unique and significant study regarding the comparative effect of different cytokinins on in vitro propagation study of Q. leucotrichophora by using different stem segments, particularly the influence of kinetin in vitro rooting and survival of in vitro raised plants in addition to shoot multiplication. This significant study could be useful for large scale production of successfully hardened plants so that it would be helpful in conservation of this important Himalayan forest tree species.

Growth of zygotic flax embryos in vitro and influence of kinetin

Embryos of flax (Linum usitatissimum L. cv. Viera) may be cultured in vitro from the globular stage of their development to germination. Kinetin added to the culture medium at the concentration of 5×10-8 mol/l accelerates embryo development, including the transition from greater expansion in width to greater expansion in length during the heart stage.

Influence of kinetin and auxins on the growth and production of diosgenin by Costus speciosus (Koen.) sm. callus derived from rhizome.

Influence of kinetin and auxins on the growth and production of diosgenin by Costus speciosus (Koen.) sm. callus derived from rhizome.

Uptake and Translocation of K+, Ca2+ and Mg2+ by Seedlings of Raphanus sativus L. Treated with Kinetin

Kinetin (6-furfurylamino-purine) applied via the nutrient solution (2 mg·l -1 = 9.3 μM) diminishes the uptake of potassium and calcium ions into radish seedlings ( Raphanus sativus L., cv. Saxa Treib). The uptake of magnesium is not affected by kinetin. Application of kinetin does not change the relative distribution of the ions in cotyledons, hypocotyl and root. Kinetintreated plants possess smaller cotyledons, shorter hypocotyls and shorter roots than the untreated controls. The formation of lateral roots is suppressed but more root hairs are formed. The influence of kinetin on ion uptake and translocation is discussed with respect to long term and short term effects of this phytohormone.

The Effect of Kinetin on the Transpiration and the Photosynthetic Capacity of Primary Leaves of Sinapis alba

Summary The influence of kinetin on the CO2 gas exchange as well as on the transpiration rate of primary leaves was examined. The CO2 uptake did not change significantly and the respiration rates remained totally unchanged. However, a distinct decrease of the transpiration rates could be observed upon kinetin treatment. Fresh weight and leaf area increased more slowly and anthocyans accumulated in kinetin plants. Our observations suggest that the effects of kinetin on the transpiration rate are not due to a primary influence of kinetin on the stomatal regulation, but to an impaired water uptake.

Beziehungen zwischen proteolytischer Aktivität und Proteinabbau in höheren Pflanzen II. Der Einfluß von exogen applizierten Phytohormonen allf die proteolytische Aktivität und den Protein-Turnover in Pisum sativum

Summary The effects of kinetin, gibberellic acid and indole acetic acid on the activities of proteinase and aminopeptidase were investigated in leaves and roots of Pisum sativum L. The influence of kinetin on protein turnover of leaves and roots of these plants was determined. Kinetin and GA 3 reduce the proteinase activity of leaves and enhance it in the roots of 14 day old plants. The effect of an IAAtreatment became visible in 28 day old plants. IAA strongly diminishes the increase of proteolytic activity which can be observed in the leaves and roots of older plants. The activity of aminopeptidase is affected only in the leaves of 14 day old plants and only by GA 3 . In kinetin-treated leaves the rate for the synthesis of protein was somewhat higher and the rate for protein degradation was somewhat diminished in comparison with the control, but the differences are not significant. In the roots kinetin stimulates protein turnover markedly. The relations between proteinase activity and gross degradation of proteins in different plant organs are discussed.

Influence of kinetin and morphactin on changes in sex expression, carbohydrate and nitrogen fractions in castor (Ricinus communis L.)

The effect of kinetin and morphactin on flower sex expression has been studied in castor. It was observed that the ratio of female to male flowers was 1:4·75 in control; 1:1·61 in kinetin and 1:3·29 in morphactin treated plants. Although the number of female flowers increased in morphactin-treated plants, the sex ratio did not alter much as there was slight decrease in male flowers. Kinetin elicited an increase in femaleness and decrease in maleness, consequently causing reduction in total number of flowers, compared to control plants. Carbohydrate contents were increased with kinetin and morphactin treatments. Reducing and non-reducing sugars were more in the female flowers than male flowers. Male flowers surpassed female flowers with respect to starch content. Treatments increased total protein and soluble nitrogen in the shoot tips, compared to those of control plants. Total and soluble nitrogen were low whereas protein nitrogen was higher in the pistillate flowers than in the staminate flowers. The modification of sex expression is discussed with respect to carbohydrate and nitrogen metabolism.

The influence of kinetin on the endogenous content of indoleacetic acid in swelling seeds of Phaseolus, Zea and Pinus and young plants of Phaseolus

AbstractTreatment of different plant materials, seeds of Phaseolus vulgaris, Zea mays and Pinus silvestris and young plants of Phaseolus, with kinetin increased the level of extractable IAA. For seeds this increase was most pronounced in bean seeds, which contained the lowest amount of endogenous IAA and cytokinins, and lower in maize seeds with high endogenous content of IAA and cytokinins. – For young bean plants the kinetin treatment significantly increased the extractable amounts of IAA from all parts of the plant, hypocotyls, cotyledons, epicotyls and primary leaves, when the cut plants were placed for 24 h in kinetin solution. For plants sprayed with kinetin solution only the primary leaves showed a significantly higher level of extractable IAA, which could be explained by the fact that the plants were growing very close together, so that the primary leaves received most of the kinetin during spraying.

The effect of kinetin on the photosynthetic apparatus of Sinapis alba

The influence of kinetin during the development of primary leaves of Sinapis alba was investigated. Kinetin treatment (6 ppm) induced an increase of dry weight, of soluble reducing sugars, soluble protein, chlorophylls, carotenoids and cytochrome f; a higher ratio of chlorophyll a to chlorophyll b, higher rates of CO2 fixation per fresh weight and higher activity of nitrite reductase, were also found. These effects are comparable with strong and blue light adaptations. On the other hand, the Hill activity with ferricyanide as the electron acceptor, the rates of CO2 fixation per chlorophyll, the ratios of chlorophyll to cytochrome f and of protein to chlorophyll did not change. Therefore we assume that the kinetin induced and the light induced adaptations are brought about by different causal reaction chains.

Influence of kinetin on the membrane potential and potassium activity in root cells of trianea bogotensis

Summary By microelectrode technique it was shown that application of 4.6 × 10 −8 M kinetin, after short-term depolarization ( + equilibrium potential.After 5-day incubation of intact roots in a 4.6 × 10 −8 M kinetin solutio a K + activity in root hairs diminished, while it remaind unchanged in atrichoblasts.The reduction of K + activity in root hairs induced by the removal of the meristematic root tip could be neutralized by kinetin application.From the results the conclusion, is drawn that kinetin influences the K + transport in the roots and that root tip is of importance for regulating K + transport in root cells.

The influence of kinetin on tobacco ringspot virus infectivity and the effect of virus infection on the cytokinin activity in intact leaves of Nicotiana glutinosa L

Intact tobacco leaves sprayed daily with kinetin (0·1 mg 1 −1) begining 9 days prior to inoculation with tobacco ringspot virus (TRSV) exhibited high levels of virus infectivity whereas leaves sprayed as above with higher levels of kinetin (1·0 mg 1 −1 and 10·0 mg 1 −1) exhibited appreciably lower levels of virus than the control plants. Conversely, the extent of viral infectivity in tobacco leaves, sprayed daily with kinetin at the three different concentrations (0·1, 1·0 and 10·0 mg 1 −1) beginning 3 days prior to inoculation, showed no appreciable difference in the pattern of virus infectivity from that of non-sprayed inoculated leaves. Extracts of infected and non-infected tobacco leaves were assayed for cytokinin activity by the radish cotyledon expansion test. Leaf extracts of TRSV-infected plants contained less cytokinin activity than leaf extracts from non-infected plants.

Differential Effects of Kinetin on Acidic Ethyl Acetate-soluble and Highly Water-soluble Gibberellin Fractions in ‘Single’ and ‘Double’Nigella damascenaL.

Differential Effects of Kinetin on Acidic Ethyl Acetate-soluble and Highly Water-soluble Gibberellin Fractions in ‘Single’ and ‘Double’<i>Nigella damascena</i>L.

Cytochemical localization of peroxidase activity in the protonema of the moss Ceratodon purpureus during differentiation of gametophore buds induced by kinetin

An increase in the activity of peroxidases under the influence of kinetin has been demonstrated in the protonema of the moss Ceratodon purpureus . It was connected above all with initiation and acceleration of the differentiation process of gametophore buds which showed a high activity of these enzymes. The increase in peroxidase activity was also noted in the degenerating intercalary cells which produced the buds. The colour reaction characteristic for peroxidases was best noticeable in the minute spherical granules (peroxysomes), nucleoli and cell walls.

Rhythmic Nitrate Reductase Activity in Leaves of Capsicum annuum L. and the Influence of Kinetin

In the expanding leaves of Capsicum annuum L. cv. California Wonder, two of the three peaks of nitrate reductase activity associated with the light period exhibit a circadian rhythm that persists in continuous light.The spray application of kinetin to the whole shoot or to leaves other than the ones used for nitrate reductase assay causes a phase shift in the activity peaks and this has been used in preliminary investigations of the character of the mechanisms controlling the timing of the peaks.There was some indication that the rate of translocation of nitrate from the roots might be involved. The levels of nitrate moving up the stem after kinetin treatment were more dependent upon the rate of sap flow than on the concentration of nitrate in the sap. For this reason, transpiration rates in whole plants were measured after kinetin treatment but no change in pattern was seen that would correlate with the phase shift in nitrate reductase activity.The occurrence of nitrate reductase peaks in excised leaves suggested a leaf-based in addition to a root-or stem-based mechanism in the timing of nitrate reductase activity in the leaves.

Transportprozesse in Vallisneria-Blättern und die Wirkung von Kinetin und Kolchizin: I. Aufnahme von α-Aminoisobuttersäure in Gewebe von Vallisneria und die Wirkung von Kinetin

Summary The uptake of α-aminoisobutyric acid (AIB)—a metabolically inert amino acid—into the leaf tissue of Vallisneria spiralis L. was studied. These are the main results: 1. The uptake proceeds proportional with time over a period of 100 hours from a 1 mM AIB solution reaching an accumulation ratio of about 5 during this period. The time proportional uptake phase continues for 24 hours from a 20 mM solution. 2. The concentration dependence of the uptake shows saturation kinetics with half saturation at 1 mM. 3. The efflux of the amino acid is very low and can be neglected at a first approximation in the· uptake experiments. 4. Kinetin (1 μ M) shows typical effects on uptake and leakage. After the kinetin effect has developed, the uptake of amino acid from a 1 mM AlB solution proceeds with a higher rate but a constant velocity during a period of 100 hours. 5. The capacity for amino acid accumulation is enhanced under the influence of kinetin. 6. The maximal velocity of uptake (V max ) reached at saturating concentrations is increased by kinetin. 7. The leakage rate is reduced by kinetin, however, this effect does not explain the higher uptake rate and accumulation ratio.

Einfluß von Kinetin auf die Kaliumbewegung in den Hypokotylen von Helianthus annuus

The influence of kinetin on potassium movement in decapitated seddlings of Helianthus annuus can be expressed in a biphasic dose response curve. 10 –6 to 10 –5 molar concentrations of kinetin cause a decrease of potassium concentration in the hypocotyls in contrast, 5 × 10 –5 molar concentration of kinetin causes an accumulation of potassium in any part of the hypocotyl. The potassium content of different segments of the hypocotyl are identical; no potassium gradient could be detected under the described experimental conditions.