Showing papers on "Kinetin published in 1971"

The effect of hormones on anthocyanin accumulation in cell cultures of Haplopappus gracilis.

Abstract: Suspension cultures of Haplopappus gracilis accumulated anthocyanin when grown in defined media with 4.5×10(-6)M 2,4-D. Transfer of cells to media with 10(-5)M kinetin or benzyladenine and no auxin or 10(-7)M NAA for 6 days resulted in increased anthocyanin concentration of the cells but the total amount of pigment was unaffected due to differences in growth rates. The cultures yielded up to 35 mg pigment per gram dry weight.Cells grown in batch culture in media with 10(-5)M kinetin and with 10(-7) M NAA or 5×10(-5)M NAA sampled and analyzed daily grew at the same rate. The concentration of anthocyanin differed, being lower in cells at 5×10(-5)M NAA. After 6 days there was a rapid increase in pigment formation, and by 14 days the concentration of anthocyanin in cells in the two media were the same.When the cells were cultured in 3.5-1 phytostats and 600 ml culture was replaced daily with 600 ml medium, anthocyanins accumulated when the NAA concentration was 10(-7)M but not at 10(-6)M. At 10(-7)M NAA the cultures remained pigmented and anthocyanin accumulation could be restored after a temporary loss of pigmentation due to an earlier, higher auxin concentration. The changes in concentration of phenylalanine ammonia-lyase did not correspond to changes in the rate of anthocyanin accumulation. The enzyme showed a maximum 4-8 h after inoculation of cells to fresh media. Cells grown on agar plates and rich in anthocyanin were observed to divide without loss of pigmentation, demonstrating that cells differentiated with respect to anthocyanin production undergo mitosis.

Stomatal opening: the role of abscisic acid

Abstract: Abscisic acid inhibits stomatal opening in isolated abaxial epidermal strips of Vicia faba. Kinetin, benzyladenine, and gibberellic acid, which can enhance stomatal apertures in intact leaves, are ...

Cytokinin-controlled Indoleacetic Acid Oxidase Isoenzymes in Tobacco Callus Cultures.

Abstract: Indoleacetic acid oxidase in tobacco callus tissues (Nicotiana tabacum L., cultivar White Gold) was resolved into seven anionic isoenzymes by polyacrylamide gel disc electrophoresis. Different concentrations of kinetin and zeatin in the presence of indoleacetic acid affected the level of this enzyme, particularly two fast-moving isoenzymes, A(5) and A(6). The optimal concentration of kinetin was 0.2 mum; increasing concentrations above this level progressively lowered the total activity of indoleacetic acid oxidase and repressed the development of isoenzymes A(5) and A(6). Actinomycin D and cycloheximide inhibited the development of these two isoenzymes under the influence of 0.2 mum kinetin, suggesting a requirement for RNA and protein synthesis. The cytokinin-promoted indoleacetic acid oxidase isoenzymes A(5) and A(6) increased with time and paralleled the dry weight increase of tobacco callus tissues, but the total activity of indoleacetic acid oxidase per unit dry weight of tobacco callus varied with time depending on the stage of plant growth.

Abscisic acid inhibition of root nodule initiation in Pisum sativum.

Abstract: The effect of exogenous abscisic acid (ABA) on root nodule formation in Pisum sativum cv. Alaska was examined. ABA supplied to the roots at 1.9×10-6M reduced the number of nodules/plant 61% without affecting root or shoot growth. The first noticeable inhibition of nodulation occurred at 3.8×10-7M ABA. ABA at a concentration of 1.9×10-6M inhibited neither root hair formation nor infection of root hairs by Rhizobium leguminosarum. Similar numbers of infection threads penetrated the cortex in both control and treated plants. ABA concentrations of 3.8×10-6M had no effect on the doubling time or maximum density of R. leguminosarum in pure cultures. Normal nodule formation involves a polyploid cortical proliferation. This response to rhizobial infection can be imitated by culturing 1-mm pea-root segments on a medium containing 4.7×10-6M kinetin. Under these conditions a highly significant reduction in the number of polyploid mitoses after 72 h is produced by 3.8×10-8M ABA. A maximum inhibition of 68% was found with 3.8×10-6M ABA. A similar range of ABA concentrations also inhibited the cytokinin-induced cell division in soybean callus. It is concluded that ABA reduces the number of root nodules/plant by inhibiting the cortical cell divisions required for root nodule formation.

Evidence for Hormonal Regulation of the Selectivity of Ion Uptake by Plant Cells

Abstract: Kinetin exerted opposing effects on the uptake of K+ and of Na+ by leaf discs of Helianthus annuus: The absorption of K+ was stimulated and that of Na+ was inhibited. The K+/Na+ ratio in kinetin-treated discs was 80–100 % higher than in control tissue. Kinetin also promoted K+ uptake by detached cotyledons which had been removed from light-grown seedlings. On the other hand, no clear effect on the absorption of Na+ by these cotyledons could be established. Benzyladenine brought about a significant elevation in the K+/Na+ ratio in attached cotyledons. It is concluded that cytokinins bring about a change in the selectivity of the cells of sunflower leaves and cotyledons towards K+ and Na+, such that the ‘affinity’ of the cells for pottasium is increased, as compared to the ‘affinity’ for sodium. The possible significance of such a change in selectivity is discussed.

Effects of Sucrose and Kinetin on Growth and Chlorophyll Synthesis in Tobacco Tissue Cultures

Abstract: Investigations were carried out on the effects of various combinations of sucrose and kinetin concentrations on growth and chlorophyll production in a green and a nongreen clone of pith callus of Nicotiana tabacum L. It was found that 2 milligrams per liter or higher amounts of kinetin induced greening in the nongreen tissue. The observations suggested that growth of the callus and synthesis of chlorophyll and soluble protein are controlled by relative concentrations of sucrose and kinetin in the medium. Kinetin was found to be inhibitory for chlorophyll synthesis in the green callus.

Ethylene production by plant cell cultures: the effect of auxins, abscisic Acid, and kinetin on ethylene production in suspension cultures of rose and ruta cells

Abstract: Cell suspension cultures of Ruta graveolens (rue) and Rosa sp. produce ethylene. Both cultures grow at a high rate in hormone-free media. The rose cells are undifferentiated while the Ruta cells differentiate and form shoots after extended culture in hormone-free medium. Addition of 2,4-dichlorophenoxyacetic acid stimulated ethylene production in Ruta cells but not in rose cells. Abscisic acid (ABA) inhibited growth and ethylene production in rose, but only ethylene production in Ruta cells. Addition of kinetin reversed the inhibition by abscisic acid in the rose cells but not in the Ruta cells. The results suggested a distinct physiological difference between the two cultures. The Ruta cells responded to the growth regulators in a manner similar to whole plants.

Physiology of Oil Seeds: II. Dormancy Release in Virginia-type Peanut Seeds by Plant Growth Regulators

Abstract: Germination, ethylene production, and carbon dioxide production by dormant Virginia-type peanuts were determined during treatments with plant growth regulators. Kinetin, benzylaminopurine, and 2-chloroethylphosphonic acid induced extensive germination above the water controls. Benzylaminopurine and 2-chloroethylphosphonic acid increased the germination of the more dormant basal seeds to a larger extent above the controls than the less dormant apical seeds. Coumarin induced a slight stimulation of germination while abscisic acid, 2,4-dichlorophenoxyacetic acid, and succinic acid 2,2-dimethylhydrazide did not stimulate germination above the controls. In addition to stimulating germination, the cytokinins also stimulated ethylene production by the seeds. In the case of benzylaminopurine, where the more dormant basal seeds were stimulated to germinate above the control to a larger extent than the less dormant apical seeds, correspondingly more ethylene production was induced in the basal seeds. However, the opposite was true of kinetin for both germination and ethylene production. When germination was extensively stimulated by the cytokinins, maximal ethylene and carbon dioxide evolution occurred at 24 and 72 hours, respectively. Abscisic acid inhibited ethylene production and germinaton of the seeds while carbon dioxide evolution was comparatively high. The crucial physiological event for germination of dormant peanut seeds was enhancement of ethylene production by the seeds.

The influence of sucrose, 2,4-D, and kinetin on the growth, fine structure, and lignin content of cultured sycamore cells.

Abstract: When suspensions of sycamore cells are cultured in a synthetic medium containing 10 mg/l 2,4-D and 025 mg/l kinetin, maximum cell yield is obtained with an initial concentration of 6 per cent sucrose There is a progressive increase in dry weight per cell, decline in extractive-free weight as a percentage of cell dry weight and increase in lignin content per cell as the initial sucrose concentration is increased from 1 per cent to 15 per cent The percentage of lignin in the extractive-free cell residue is further enhanced by increasing the level of 2,4-D to 10 mg/l or by growing the cells in an auxin-free medium containing 10 mg/l kinetin

The ultrastructure of wheat leaves I. Changes due to natural senescence and the effects of kinetin and ABA on detached leaves incubated in the dark

Abstract: Detached wheat leaves incubated in water in darkness rapidly lose starch and are ultrastructurally degenerate by 5 days. Chloroplast ribosomes disappear before cytoplasmic ribosomes and groups of wavy membranes can be detected in both mature and degenerating chloroplasts. Large lipid bodies appear in the cytoplasm and vacuole during senescence, and osmiophilic fibrils and deposits develop in the microbodies. Treatment with kinetin via the transpiration stream markedly delays the loss of starch and maintains, but does not increase, chloroplast and cytoplasmic ribosome populations. ABA accelerates degenerative changes as compared with the water treated control leaves but does not induce any specific ultrastructural effects.

The effects of abscisic acid, kinetin and 5-fluorouracil on ribonucleic acid and protein synthesis in senescing radish leaf disks.

Abstract: The effects of abscisic acid and kinetin on RNA synthesis in senescing radish leaf disks were investigated using the improved resolution afforded by polyacrylamide gel electrophoresis. Kinetin stimulated and abscisic acid inhibited incorporation of radioactivity into cytoplasmic ribosomal RNA and soluble RNA. Chloroplast ribosomal RNA synthesis appeared to be confined to the period of leaf expansion and was not detected in fully mature leaves. The effects of kinetin in retarding and of abscisic acid in accelerating leaf senescence were not altered by the inhibition of cytoplasmic ribosomal RNA synthesis with 5-fluorouracil. Following inhibition of cytoplasmic ribosomal RNA synthesis with 5-fluorouracil, kinetin stimulated and abscisic acid inhibited incorporation of radioactivity into polydisperse RNA. These results are discussed in relation to the possible mode of action of kinetin and abscisic acid in senescing leaf tissue.

Phytochrome-mediated Carotenoid Biosynthesis and Its Influence by Plant Hormones

Abstract: Lycopenc biosynthesis of parenchyma chromoplasts was studied in detached tomato fruits, Lycopersicum esculentum Mill, cv. Waltham Forcing, and found to be phytochrome mediated. A few minutes of red light during the day enhanced lycopene formation. Far-red irradiation did not enhance lyco-pene biosynthesis. Far-red following red nullified the promotive effect of red light. Lycopene content increased two-fold in the presence of abscisic acid. Ripening of tomatoes was inhibited when gibberellin, kinetin and ascorbic acid were applied to green tomatoes. Gibberellin (A3) was more inhibitory to lycopene synthesis than kinetin.

Specific Effects of Kinetin on the Uptake of Monovalent Cations by Sunflower Cotyledons

Abstract: Kinetin promoted the uptake of K+ and Rb+ into detached sunflower cotyledons. This action was concomitant with an acceleration of growth. A slighter promotion of Li+ uptake was also noted, but there was no consistent influence on that of Na+. A small inhibitory effect on NH4+4 uptake was apparent when the latter was computed per average weight of sample during the course of incubation. Light also promoted the growth of the cotyledons, but depressed their capacity to absorb potassium. The action of kinetin on cotyledons removed from 5–7 day old seedlings was weaker than on those removed from 2–4 day old seedlings with regard to growth but stronger with regards to K+ uptake. When K+ uptake by cotyledons taken from 7-day old seedlings was followed with time the kinetin effect was already detectable within a few hours, but it became more pronounced after 10 hours' incubation. Kinetin did not accelerate growth or K+ uptake in hypo-cotyl segments. IAA, which was previously shown to promote these processes in hypocotyl segments, inhibited them in cotyledons. A working hypothesis is suggested according to which endogenous auxins and cytokinins regulate the absorption of K+ in shoot cells of the intact plant in a manner similar to that in which they act in excised tissues and in this way affect the distribution and redistribution of K+ in the shoot; and that they are among the factors which determine the selectivity of ion uptake in the intact plant.

Metabolism of isoflavones and coumestanes in cell and callus suspension cultures of Phaseolus aureus Roxb

Abstract: The isoflavone daidzein, the coumestanes coumestrol and soyagol as well as 2′,4,4′-trihydroxychalcone were isolated from callus and cell suspensions of root tip tissue from Phaseolus aureus Roxb. Upon prolonged culturing callus suspensions gradually became cell suspensions, a process which was accompanied by a decrease in the accumulation of phenolics. Upon transfer of the cells into 3 different media containing β-indolyl acetic acid, kinetin or α-naphthalene acetic acid, a drastic increase in the amount of coumestrol was measured.

The mechanism of apical dominance in Coleus

Abstract: The development of lateral buds in isolated stems of Coleus blumei is inhibited by low concentrations of indoleacetic acid or other auxins, just as in other plants. The inhibition can be fully reversed by kinetin, about 3 times as much kinetin as IAA being needed. However, the outgrowth of the same lateral buds on intact Coleus plants is sensitive to environmental conditions, well-nourished plants in full daylight often showing little inhibition by applied auxin. It is shown that (a) the solvent used for IAA, (b) the light intensity and (c) the nitrogen and phosphorus nutrition, all control the sensitivity of the buds to auxin inhibition. Using water instead of lanolin, lowering the light intensity or decreasing the supply of either nitrogen or phosphorus all increase the degree of apical dominance.

Action of kinetin on cotyledons of fenugreek.

Abstract: Isolated cotyledons of fenugreek (Trigonella foenum graecum L.), which respond rapidly and specifically to the application of cytokinins with stimulated expansion, have been used to study the primary action of kinetin. Gross chemical analysis showed that ribonucleic acid increased within 24 hours in response to kinetin application. 8-Azaguanine inhibited both kinetin-induced expansion and RNA synthesis; 5-fluorodeoxyuridine inhibited only the RNA synthesis.Cotyledons produced nitrate reductase activity in response to 20 mm nitrate only in the presence of either light or kinetin and especially in the presence of both. Abscisic acid and inhibitors of RNA and protein synthesis depressed this response. Inhibitors affecting chloroplast development and function did not reduce the response in the presence of light and kinetin.In vitro incorporation of (14)C-l-leucine and (14)C-l-phenyl-alanine into protein by various recombinations of microsomal and 160,000g supernatant fractions varied according to the pretreatment which the cotyledons had received before the preparation of the fractions. Stimulatory effects were mainly associated with the microsomal fractions.The formation of leucine-, valine-, and tyrosine-tRNA complexes by high speed supernatant fractions from differently pretreated cotyledons was also compared. The sharp stimulation of the process by adding tRNA was found to be independent of the kind of preincubation that the cotyledons used for the tRNA extraction had received.It is concluded that the evidence is not in favor of kinetin correcting specific tRNA deficiencies. Kinetin removes a limitation that prevents the synthesis of RNA and genome expression.

Quantitative Relationship between Various Growth Substances and Bud Production in Funaria hygrometrica. A bioassay for abscisic acid

Abstract: Eleven growth substances were tested for their bud producing capacity in Funaria hygrometrica. IAA and gibberellic acid showed no response, neither did inositol, abscisic acid and adenine. The cytokinins: benzylaminopurine, kinetin and mercaptopurine showed a quantitative relationship while methylaminopurine did not. When different amounts of abscisic acid were added together with 10 μg kinetin (which gave maximal production of buds), there existed a linear relationship between reduction in buds and abscisic acid added. Results are obtained in two weeks and it is therefore a fairly quick method for assaying certain cytokinin and also abscisic acid.

The culture of apical buds of xanthium and their use as a bioassay for flowering activity of ecdysterone

Abstract: Conditions were developed for the sterile culture of shoot tips of Xanthium pensylvanicum Wallr. for use as a bioassay for flower-controlling chemicals. By using a modified Murashige-Skoog medium (minus the auxin but including kinetin) and light intensity much higher than usual for plant tissue cultures, fast growth and development of the shoot tips was achieved. Under short-day conditions (8 hr day: 16 hr night), the cultures from vegetative shoots flowered and fruited; under noninductive conditions (using a 2 hr light-break in the middle of the dark period), the shoot tips continued vegetative development. Both intact plants and cultured tips could be photoinduced in the first days after germination. Ecdysterone, a potent insect moulting hormone, was tested in the bioassay system. It was without either qualitative or quantitative effect on flowering or vegetative development on either cultured shoot tips or intact plants irrespective of whether they were under inductive or noninductive photoperiodic conditions. DESPITE ATTEMPTS by researchers who had extensive experience with sterile cultures (e.g., Wetmore, 1956), shoot tips of the short-day plant (SDP) Xanthium have apparently not been successfully cultured. It would be useful to accomplish this for two reasons. First, earlier cultures of the shoot tips of the SDP Perilla had provided interesting confirmation and extensions of the hypothesis that leaves in long day (LD) were actively inhibiting flowering, because Perilla shoot tips even when cultured in LD developed inflorescences up to the sporogenous stage if the larger and older leaves were excised before implanting (Raghavan and Jacobs, 1961). If the youngest two leaf-pairs below the apical bud were not excised, however, the cultures remained vegetative under LD conditions (although they flowered under SD). To elucidate what controls flowering, it is of obvious interest to see if the results from Perilla apply to other photoperiodically sensitive genera. Xanthium was chosen because it has been so thoroughly investigated and has a cluster of intriguing differences from Perilla in its flowering physiology (such as its much greater "sensitivity" to photoinduction-cf Evans, 1969). Secondly, if we succeeded in culturing Xanthium shoot tips but they remained vegetative in LD, we planned to use the cultured apical buds as an improved 1 Received for publication 15 March 1971. Research supported by funds provided by the Eugene Higgins Trust Fund, by facilities made available by the Whitehall and John A. Hartford Foundations to the Department of Biology, Princeton University, and by a Hoyt Foundation grant and NSF grants to W. P. Jacobs. The aid of Anthony Procaccini in growing and maintaining the plants, of Susan Kirk in the early culture work, and of Dan Suthers in taking the photographs is gratefully acknowledged. bioassay for testing flower-promoting extracts and solutions. Cultured buds would serve as improved bioassay material because they would be sterile (thus obviating artefacts from bacterial interactions with compounds added). They would also be a simpler system than the whole plant: we would be testing the flower-inducing activity of an extract more directly by adding it to a cultured apical bud rather than to the older leaves of the complete plant. In the latter case, active material in the extract would have to penetrate the leaf, avoid metabolism there, be moved out of the leaf and up the stem to the reactive meristem and there bring about the changed activity that results in flowering. By using cultured buds we hoped to "isolate" the major reactive system (as suggested by the "PESIGS" rules, Jacobs, 1959), and avoid these secondary pitfalls. [Other investigators have independently thought of using cultured shoot tips as bioassays for flower-promoting extracts (e.g., Nitsch and Nitsch, 1967; Nitsch, 1968).] The current paper reports on progress made since We started culturing Xanthium in mid-1965. Our first results with cultured buds forced us to re-examine thoroughly floral development in intact Xanthium plants because we discovered that the normal development of the many separate male and female inflorescences was inadequately represented by descriptions restricted to the single, terminal, male inflorescence, as used by most earlier physiologists studying Xanthium flowering. This fuller description of normal floral development is now published and was used for interpreting the cultures (Kirk, Morrow, and Jacobs, 1967). One of our aims was to be ready to use a wider variety of cultural conditions than tissue culturists

Regulation of Growth in Avena Stem Segments by Gibberellic Acid and Kinetin

Abstract: Kinetin at physiological concentrations causes significant reduction of GA3-promoted growth in excised Avena stem segments. Kinetin is therefore considered to be a gibberellin-antagonist in this system. A Lineweaver-Burke plot reveals that kinetin acts non-competitively with GA3. The kinetin inhibition of GA3-promoted growth can be seen within 6 hours. It was found that soluble protein is markedly increased by kinetin in the tissue during the first 3 hours, thus preceding the inhibition of GA3-promoted growth by several hours. At the cellular level, kinetin negated the blocking effect of GA3 on cell division in the intercalary meristem portions of these segments. In fact, kinetin promotes both lateral and longitudinal cell divisions in intercalary meristem cells.

Initiation of DNA synthesis by kinetin and experimental factors in tobacco pith tissues in vitro

Abstract: Since previous investigations had suggested that kinetin, like auxin, may initiate DNA synthesis in tobacco pith cells, a study was undertaken to learn whether the observed incorporation of tritiated thymidine into nuclear DNA in the presence of kinetin could be explained by different experimental factors.Pith tissues were isolated and allowed to rest a few days after excision and they were then placed on White's basic medium or on that medium supplemented with either one or both of the growth regulators in the presence of tritiated thymidine.The results of those studies, obtained by radioautographic and liquid scintillation counting methods, showed no statistically significant differences between pith tissues kept on the control medium and those on kinetin-containing medium. Similar tissues placed on an auxin or auxin- and kinetin-containing medium showed, as expected, a significant incorporation of tritiated thymidine into the DNA of pith cell nuclei.

Morphogenetic studies on cultured mature endosperm of croton bonplandianum

Abstract: Summary The mature endosperm of Croton bonplandianum proliferated profusely on White's medium (WM) + 2 ppm 2,4-D + 5 ppm kinetin + 2500 ppm yeast extract. Association with the embryo was essential for initiation of proliferation of mature endosperm. Tracheidal cells usually differentiated. Twelve-month-old callus contained predominantly triploid and hexaploid cells. When the callus obtained on WM + 2,4-D + kinetin + yeast extract was subcultured on WM triploid roots formed in 25% of the cultures. At 10−7 M, IBA, IAA, or NAA, in WM, promoted rooting; IBA was most effective. Attempts to induce shoot differentiation failed.

The ultrastructure of wheat leaves II. The effects of kinetin and ABA on detached leaves incubated in the light

Abstract: Incubation of detached wheat leaves in water in the light results in a temporary accumulation of starch in the chloroplasts. This accumulation is prevented by treatment with ABA. On the other hand, treatment of the detached leaves with kinetin causes a large increase in the size and number of starch grains.

Post-pollination phenomena in orchid flowers. ii. induction of symptoms by abscisic acid and its interactions with auxin, gibberellic acid and kinetin *

Abstract: New Phytol. ( 1971) 70, 333- 341. POST-POLLINATION PHENOMENA IN ORCHID FLOWERS II. INDUCTION OF SYMPTOMS BY ABSCISIC ACID AND ITS INTERACTIONS WITH AUXIN, GIBBERELLIC ACID AND KINETIN* BY JOSEPH ARDITTI, BRIGITTA FLICK AND DAVID JEFFREY Department of Devewpmental and Cell Biowgy, University of California, Irvine, California 92664, and Division of Natural Sciences, Universi.ty of California, Santa Cruz, California 95060, U.S.A. (Received 15 June 1970) SUMMARY Applications of ABA to Cymbidium flowers induce some, but not all, po.st-pollination symptoms. Anthocyanin levels in sepals, petals, columns and labella are raised; flowers wilt; dorsal sepals become hooded; caJli develop colouration while losing turgidity; columns do not swell, lose very little curvature; and stigmas do not close. Combinations of ABA and NAA induce all post-pollination phenomena, but lower anthocyanin content than treatments with ABA only. ABA plus GA 3 have effects which are similar to those of ABA alone, except that anthocyanin levels are reduced. The same is essentially true of ABA-kinetin mixtures but intensities of the effects are different and with some concentration ratios, stigmatic closure also occurs. The effects of ABA and its interactions with GA 3 , kinetin or NAA are explained in terms of the roles these hormones may play in synthesis of nucleic acids and enzymes. INTRODUCTION Orchid flowers, including those of Cymbidium, undergo remarkable changes following pollination. The perianth wilts or some of its segments may become green and leaf-like. Stigmas close while columns swell and lose their curvature. Both columns and labella produce 'anthocyanins whereas the usually yellow calli (in Cymbidium) turn red or orange and lose their turgidity. Within the ovary, ovule development is initiated, con- tinues at a rate commensurate with pollen tube growth and climaxes in fertilization 26-45 days later (Wirth and Withner, 1959). Applications of auxins to the stigma initiate most of these changes, although ovule development is aborted (for a short review see Arditti and Knauft, 1969). This is of particular interest since either pollination or auxin initiate events of such diversity that they would seem to be normally unrelated. Wilting of the perianth is an aspect of senescence; closing of the stigma and swelling of the column represent growth due to cell enlargement; greening and persistence of the column are modifications in function; changes in segments of the perianth involve organogenesis; ovule development is morphogenesis; synthesis of anthocyanins results from newly expressed biochemical capabilities; and the reduced turgidity of the calli implies changes in water relations. * See Arditti and Knauft (1969) for part I. D