Showing papers in "Biologia Plantarum in 1972"
TL;DR: Using regression analysis a proof of the relation between the electric capacitance and the root surface in maize, sunflower, oats and onion plants was given and is possible to exploit in the selection of plants for a well—developed root system.
Abstract: Using regression analysis a proof of the relation between the electric capacitance and the root surface in maize, sunflower, oats and onion plants was given. This dependence is possible to exploit in the selection of plants (of the same population grown under the same conditions) for a well—developed root system.
93 citations
TL;DR: Results obtained indicate that reduced nitrate assimilation due to the depression of nitrate reductase activity caused by kinetin probably contributes to the negative growth effect of Kinetin in pea root segments grown in nitrate medium.
Abstract: Nitrate reductase (NO3R) activity, nitrite reductase (NO2R) activity and NADH2 dependent glutamate dehydrogenase (GDH) activity were followed in extracts from excised pea roots incubated under aseptic conditions for 9 and 24 h in nitrate containing nutrient medium to which IAA was added in concentrations promoting lateral root formation (1 × 10−5; 3 × 10−5; 5 × 10−5 M) and kinetin in concentrations which reduce lateral root formation (0.1; 1; 5 mg 1−1, that is 4.65 × 10−7;4.65 × 10−6 and 2.3 × 10−5 M). NO3R activity was not influenced by IAA, NO2R activity was slightly depressed by IAA after 24 h incubation and GDH activity was slightly increased after 24 h incubation in the presence of IAA. Kinetin decreased NO3R activity significantly both after 9 h and 24 h incubation, slightly increased NO2R activity after 9 h incubation but slightly decreased it after 24 h incubation, and did not affect GDH activity after 24 h incubation. However, when applied together with IAA, kinetin abolished the promoting effect of IAA on GDH activity. IAA neither reversed nor accentuated the effect of kinetin on NO2R activity. Nevertheless the depressing effect of kinetin on NO3R activity was emphasized by the presence of IAA after 9 h incubation. The results obtained indicate that reduced nitrate assimilation due to the depression of nitrate reductase activity caused by kinetin probably contributes to the negative growth effect of kinetin in pea root segments grown in nitrate medium.
24 citations
TL;DR: Two plants which were sectorial chimeras in the two tested characters,i.e. in the length of stomata and their frequency, were found among the 17 individuals regenerated from the stem pith of the same marrow stem kale plant.
Abstract: Two plants which were sectorial chimeras in the two tested characters,i.e. in the length of stomata and their frequency, were found among the 17 individuals regenerated from the stem pith of the same marrow stem kale plant. The chimeral character was also expressed in the size and variability of pollen grains and in the number of colpae in their exine. The different ploidy of sectors (2n, 4n) was confirmed cytologically.
22 citations
TL;DR: The difference in IAA-decarboxylation activity between the illumination and dark treated explants was relatively small, nevertheless it was consistent and appears to be very important from a physiological point of view suggesting that there exists a regulatory relationin vivo between IAA degradation and the presence of phenolsin plant tissue.
Abstract: The homogenate of different strawberry organs inhibits the degradation of IAA in the presence of horse radish peroxidase, while intact strawberry tissues are able to degrade IAA. The chemical nature of peroxidase inhibitors present, in strawberry tissues was in vestigated. Using paper chromatography the following polyphenolic substances inhibiting peroxidase activity were identified: chlorogenic, caffeic, ellagic, gentisic, gallic, and vanillic acids, quercetin and pelarginidin. Monophenolic compounds, also present in strawberry, such as p-hydroxy-phenyloacetic acid and p-hydroxybenzoic acid, are strong stimulators of IAA oxidase. Abscisic acid in very high concentration (1×10−4M) enhances degradation of IAA by peroxidase.
21 citations
TL;DR: The relation between the effect of ABA and the stage of stratification is closer in the case of GA4 than GA7, and it is assumed ABA to inhibit the gibberellin biosynthesis.
Abstract: The content of endogenous GA4 and GA7 was determined in apple embryos cultured either on water or in the presence of ABA solution. The embryos were isolated from dormant seeds and from seeds removed from stratification which was effected either in water or in the presence of ABA. The influence of ABA on the decrease of two GAs levels was proved. The relation between the effect of ABA and the stage of stratification is closer in the case of GA4 than GA7. It is assumed ABA to inhibit the gibberellin biosynthesis.
21 citations
TL;DR: It was revealed that both the degree and the variability of the seed set depend on the age of the experimental flowers, and casein hydrolysate at a concentration of 500 μg ml−1 nutrient medium favourably affected the seed formationin vitro.
Abstract: The paper deals with the effect of some factors on the set of mature seeds in artificially pollinated excised placentae cultivatedin vitro.
20 citations
TL;DR: Anthers ofLycium halimifolium were grown in vitro at the following stages of development: tetrads, microspores and binucleate pollen grains andPollen plantlets were obtained only from anthers inoculated at the stage of microspore.
Abstract: Anthers ofLycium halimifolium were grownin vitro at the following stages of development: tetrads, microspores and binucleate pollen grains. Pollen plantlets were obtained only from anthers inoculated at the stage of microspores. The growth of androgenic embryos was very slow. Mature embryos were formed in about 3% of the inoculated anthers. The largest number of embryos obtained from one anther was 4.
20 citations
TL;DR: The effect of growth retarding amino acids (L-aspartic acid,L-leucine, L-methionine, andL-threonine) on nitrate reductase, nitrite reduct enzyme, and NADH2 dependent glutamate dehydrogenase in excised pea roots was followed.
Abstract: The effect of growth retarding amino acids (L-aspartic acid,L-leucine,L-methionine, andL-threonine) on nitrate reductase (NO3R), nitrite reductase (NO2R), and NADH2 dependent glutamate dehydrogenase (GDH) in excised pea roots was followed,L-methionine andL-threonine slightly depressed NO3R activity,L-aspartic acid enhanced NO2R and GDH activities.L-methionine andL-threonine also slightly decreased nitrate uptake. The results obtained are discussed in connection with the growth effects of the amino acids investigated.
19 citations
TL;DR: A strong correlation existed between catalase and peroxidase activity with respiration, indicating that the activity of these enzymes can be used as an indicator of metabolism, and therefore can be considered as part of the respiratory mechanism of rice seedlings.
Abstract: Changes in the percentage of seed germination, the growth and respiration rate of the seedlings were observed at 15-day intervals from the stage of the full germination capacity of rice (Oryza saliva L.) seeds till they became non-viable. At the beginning, the respiration rate changed but little, but afterwards, with the approach of non-viability, the rate declined sharply. A positive correlation of respiration with a decrease in the germination percentage and the length of seedlings and a negative correlation with days of storage were also established. A strong correlation existed between catalase and peroxidase activity with respiration, indicating that the activity of these enzymes can be used as an indicator of metabolism, and therefore can be considered as part of the respiratory mechanism of rice seedlings.
19 citations
TL;DR: Both CCC and cold (5°C) treatment gave rise to an increased content of the water-soluble proteins in leaf tissue of the winter rape, irrespective of the day length as discussed by the authors.
Abstract: Both CCC and cold (5°C) treatment gave rise to an increased content of the water-soluble proteins in leaf tissue of the winter rape, irrespective of the day length This effect was accompanied by a decrease of the insoluble nitrogen compounds content, mainly under theLD (the 16 hour day) The applied retardant also stimulated the consumption of the structural compounds induced by low temperature
17 citations
TL;DR: Using immunochemical methods the authors investigated the evolutionary taxonomic distribution of the reserve seed protein “phaseolin” in cultivars of Phaseolus vulgaris, in a series of species ofPhaseolus, and in representatives of some additional genera ofViciaceae.
Abstract: Using immunochemical methods the authors investigated the evolutionary taxonomic distribution of the reserve seed protein “phaseolin” in cultivars ofPhaseolus vulgaris, in a series of species ofPhaseolus, and in representatives of some additional genera ofViciaceae.
TL;DR: Germination ofPinus banksiana seeds is controlled by the photoreversible phytochrome reaction and in both cases it is possible to reverse the effect of a single red light irradiation by applying far red light (730 nm).
Abstract: Germination ofPinus banksiana seeds is controlled by the photoreversible phytochrome reaction. The seeds, even unimbibed, are sensitive to red light. At 660 nm, the energy required to promote germination to the same order of magnitude is much higher for unimbibed seeds than for the imbibed ones. In both cases it is possible to reverse the effect of a single red light irradiation by applying far red light (730 nm).
TL;DR: Therefore, OSDD is apparently of virus origin; mycoplasmas-like bodies found formerly in the OSDD vector are probably not involved in OSDD etiology.
Abstract: Virus particles (approximately 73 nm in diam.) usually showing an inner capside (45 nm in diam.) and similar to diplornaviruses, esp. reoviruses, were found in some cells of enations inAvena sativa andArrhenatherum elatius leaves infected with the oat sterile dwarf disease (OSDD). (The same virus particles were described by the authors in 1966 in the leafhopper vector.)
TL;DR: A mycoplasma-like microorganism was identified on electron micrographs of ultrathin sections of roots and abnormal underground sprouts growing from roots of young apple trees artificially infected with the proliferation disease.
Abstract: A mycoplasma-like microorganism was identified on electron micrographs of ultrathin sections of roots and abnormal underground sprouts growing from roots of young apple trees artificially infected with the proliferation disease Specimens taken in November, contained mycoplasmas at various stages of reproduction in sieve tubes of the host Mycoplasma-like bodies occurred especially in abnormal underground sprouts, and rarely also in lateral roots
TL;DR: With the completely induced plants ABA hastened flowering and the rise in branching was observed in all the treatment 48 h following the application of growth substances, which were ineffective in increasing the mitotic activity of the shoot apex at the suboptimal level of induction.
Abstract: Abscisic acid (ABA) (5 x 10-4M and 5 x 10-5M) and gibberellic acid (1 x 10-4M) was applied to the plumula ofChenopodium plants with partly (one dark period) or completely (three dark periods) fulfilled photoperiodic requirements for flowering. Morphological and cytoogical criteria were used to investigate the time-course of the differentiation of the treated shoot apices. Both substances were ineffective in increasing the mitotic activity of the shoot apex at the suboptimal level of induction. The degree of branching was temporarily stimulated by ABA and GA treatment under these conditions. Moreover, GA caused the elongation of the shoot apex. With the completely induced plants ABA hastened flowering and the rise in branching was observed in all the treatment 48 h following the application of growth substances.
TL;DR: In this article, the formation of the isothiocyanate group of the aglycone of glucobrassicin (Glubr) an indole glucosinolate present in relatively large quantities in plants of the familyBrassicaceae, was studied.
Abstract: The formation of the isothiocyanate group of the aglycone of glucobrassicin (Glubr) an indole glucosinolate present in relatively large quantities in plants of the familyBrassicaceae, was studied. Labelled Glubr was synthesized from L-tryptophan-3-14C-amino15N in winter rape hypocotyl segments. After extraction it was finally isolated in a crystalline state by mixed crystallization with added inactive Glubr tetramethylammonium salt. The specific activity of14C and the atoms % excess15N were determined in both the precursor and the product. The ratio14C/15N as well as the values of dilution of14C and15N were in agreement in the precursor and in the final product. This shows,inter alie, that during the biosynthesis of Glubr, L-tryptophan is not deaminated. Thus the presumed isothiocyanate group of Glubr is synthesized on the α-carbon of the L-tryptophan alanine chain, the α-carbon together with the attached nitrogen pass directly from the precursor into the Glubr aglycone. This represents a type of glucosinolate aglycone biosynthesis where the carbon chain of the initial amino acid is not elongated. This finding is supported by the fact that L-tryptophan-l-14C does not yield labelled Glubr the C1 carbon being decarboxylated during Glubr synthesis.
TL;DR: There was no direct correlation between the activity of a given compound as an inhibitor of yellowing in darkness, and the degree of inhibition of RNA synthesis.
Abstract: Cycloheximide, ethionine,p-fluorophenylalanine, 6-azauracil, 5-diazouracil and vanillin, applied at relatively high concentrations, retarded the yellowing of kale (Brassica oleracea L. var.acephala) leaf discs in darkness, and stimulated it in light. All the compounds inhibited protein synthesis and retarded protein breakdown. Cycloheximide,p-fluorophenylalanine, diazouracil and vanillin also inhibited the incorporation of uracil-14C into RNA of senescing discs. Abscisic acid and 2-chloroethylphosphonic acid accelerated yellowing both in darkness and in light and stimulated the protein breakdown in senescing discs. Abscisic acid inhibited the chlorophyll, protein and RNA synthesis in detached, greening cucumber cotyledons. There was no direct correlation between the activity of a given compound as an inhibitor of yellowing in darkness, and the degree of inhibition of RNA synthesis. The arrest of yellowing in darkness is possibly a consequence of the retarded rate of protein breakdown. Yellowing in light, on the contrary, is dependent on the actual rate of protein synthesis.
TL;DR: A cybernetic model shows that synergism between auxin, gibberellin and cytokinin in xylem and phloem differentiation and in starch metabolism is very important for understanding correlations in apple trees.
Abstract: Growth correlations among lateral shoots of one-year-old apple treesMalusMill., were described. The existence of a mechanism was postulated through which small original differences between buds or young shoots are quickly augmented, thus leading to differentiation of long shoots and short shoots. Existing hypotheses do not seem sufficient for explaining correlative phenomena of this type; a cybernetic approach was therefore applied. Studying growth correlations in terms of cybernetic revealed that previous hypotheses concerning correlations do not contradict each other as often thought, but depict different links in a more general chain of events. A cybernetic model points out the importance of root influences in interaction among shoots. It also shows that synergism between auxin, gibberellin and cytokinin in xylem and phloem differentiation and in starch metabolism is very important for understanding correlations in apple trees.
TL;DR: There is a relatively high auxin level in young fruits, mature leaves and resting buds during the mid-summer period whereas the accumulation of clearcut inhibitions is signalled by the results of lettuce bioassay.
Abstract: The character of endogenous growth substances was investigated in developing buds, young fruits and mature walnut leaves. The relatively high content of auxins and gibberellin-like substances was found by means of bioassays in the youngest primordia of vegetative buds. The level of auxins drops in the further course of primordia transformation into the staminate catkins. The development of leaf-buds is characterized by the accumulation of inhibitory activity as revealed by theAvena bioassay, whereas the data obtained from the lettuce bioassay indicate a pronounced stimulation. The onset of terminal bud development is also accompanied by inhibitions and it is only with pistillate flower differentiation that the temporary rise in auxin level is observed. An inhibitory activity was found in these extracts using lettuce bioassay. There is a relatively high auxin level in young fruits, mature leaves and resting buds during the mid-summer period whereas the accumulation of clearcut inhibitions is signalled by the results of lettuce bioassay.
TL;DR: The effects of several growth and trophic substances on bud and root neoformation on leaf fragments ofBegonia rex were studied in precisely defined environmental conditions and IAA, depending on the type of treatment, had different effects.
Abstract: The effects of several growth and trophic substances on bud and root neoformation on leaf fragments ofBegonia rex were studied in precisely defined environmental conditions. IAA, depending on the type of treatment, had different effects. In aseptic cultures, a notable stimulation of bud formation was observed at certain concentrations. However, non aseptic treatments of IAA had no visible effects except at very high concentrations.(10−3 M) where bud formation was totally inhibited and root formation was favored. NAA, at 10−6 M and 10−5 M strongly stimulated root formation and inhibited shoot formation. All the cytokinins used stimulated bud formation and inhibited partially or totally root formation. Gibberellic acid inhibited bud and root formation. Glucose and sucrose clearly stimulated bud and root formation and sucrose, when applied simultaneously with other growth substances, modified the effects of these substances alone. The most favorable environmental conditions were at 24°C in a 24 h photoperiod but other temperatures (17 to 27°C) and photoperiods (9 or 16 h) did not prevent neoformation.
TL;DR: There is a theoretical possibility of generative reproduction (after the extirpation of bulblets) of Allium sativum and the aberration disturbance does not seem to spoil the vegetative development but on the contrary to give it a vigorous character.
Abstract: The meioses of four sterile species in the genusAllium which develop bulblets in the inflorescences instead of seeds were compared, namelyAllium sativum, A. cepa var.viviparum, A. carinatum, andA. oleraceum. The most important of them,A. sativum, is an ancient cultivated plant and its vegetative reproduction prevents it from more rapid evolution such as is known in generatively propagated cultivated plants.A. sativum shows fully normal meiosis. After the disintegration of the tetrads, however, the blockade of 1. pm takes place. The cause of the blockade has not yet been cleared up. Removing of bulblets appeared as having no influence on the development of microgones. It is assumed that there may be a viral phenomenon causing a disease of the tapetum without disturbing other functions. InA. cepa var.viviparum there was observed a heavy aberration disturbance in the meiosis, which had already been signalled by the mitosis. On this ground 1. pm does not occur and sterility is fully justified. The aberration disturbance does not seem to spoil the vegetative development but on the contrary to give it a vigorous character.A. carinatum andA. oleraceum are triploid and tetraploid forms; in the meiosis they form various configurations—univalents, bivalents, trivalents, and quadrivalents. The following irregular chromosome distribution results in the coming into existence of variously valuable gametes. 1. pm takes place. There is a theoretical possibility of generative reproduction (after the extirpation of bulblets).
TL;DR: No influence of IAA on the endogenous estrogen content in bean plants was stated, but kinetin was found to increase and abscisic acid to decrease the amounts of estrogens.
Abstract: No influence of IAA on the endogenous estrogen content in bean plants was stated. At the same time kinetin was found to increase and abscisic acid to decrease the amounts of estrogens.
TL;DR: A not too high radiation sensitivity was observed in the metabolic pathway leading from L-tryptophan to glucobrassicin, which in these plants is a precursor of indolic glucosinolates glucobRassicin and neoglucobr Jurassicin.
Abstract: The metabolism of14C-anthranilic acid (14C-AA) in kohlrabi (Brassica oleracea L vargongylodes L) and the effect of radiation gamma60Co on this metabolism was investigated In hypocotylar segmnents of seven days old etiolated seedlings14C-AA was metabolised par, tially to its detoxication product14C-β-glucoside of AA Simultaneously L-tryptophan was also formed, which in these plants is a precursor of indolic glucosinolates glucobrassicin and neoglucobrassicin
TL;DR: The correlative function of a root in the renewal of the apical dominance can, to some extent, be directly simulated by exogenous gibberellin, as has been demonstrated in the experiment with decapitated pea seedlings deprived of one cotyledon.
Abstract: The interaction of GA and IAA in apical dominance was investigated in an experiment in which first of all an IAA paste was applied to the cut areas formed by the decapitation of epicotyl apices of pea seedlings, followed after one week by the application of a 0.25 % GA paste. The latter treatment was able to overcome the growth inhibition of cotylary buds induced by a 0.03 % IAA paste, but not that caused by 0.06 and 0.12 % IAA pastes.
TL;DR: The meristematic zone, elongation zone and zone with the beginning differentiation differ in their activity of individual isoenzymes, which is dependent on the extraction of Triton X-100 etc.
Abstract: Highly active NAD-MDH (E.C.1.1.1.37) and low activity of NADP-MDH (E.C.1.1.1.40) were found inVicia faba roots. The NAD-MDH activity is associated with 6 to 12 isoenzymes. The number of isoenzymes is dependent on the extraction (use of Triton X-100etc.) and detection procudures (presence of KCN, phenazine methosulphate). The meristematic zone does not contain one isoenzyme (X) which is present in the other two zones. The meristematic zone, elongation zone and zone with the beginning differentiation differ in their activity of individual isoenzymes.
TL;DR: The constant values of water potential gradient accompanying various levels of water flow rate were found in kale leaf tissue segments as mentioned in this paper, indicating the decrease of resistance to water flow as flow rate increased.
Abstract: The constant values of water potential gradient accompanying various levels of water flow rate were found in kale leaf tissue segments. This constancy might indicate the decrease of resistance to water flow as flow rate increased and this decrease of resistance was confirmed.
TL;DR: In plants treated with FUDR, a decrease in DNA and RNA synthesis was observed and in plants to which THY was applied at a time when it was no longer able to reverse the inhibition of flowering, the results obtained from different experiments were not identical.
Abstract: The nucleic acid fractions obtained by chromatography on MAK columns were compared in 4 variants ofChenopodium rubrum plants treated in different ways during floral induction. The first variant was normally induced to flowering. The second one was inhibited by application of FUDR to the apical bud on the third day of induction. In the third variant the inhibitory effect of FUDR was reversed by application of THY 24 h after FUDR treatment. In the fourth variant THY was applied 24 h after the termination of induction at a time when it was no longer able to reverse the inhibition of flowering. In plants treated with FUDR, a decrease in DNA and RNA synthesis was observed. After reversal of the inhibitory effect of FUDR by THY, DNA synthesis remained somewhat lower than in the control variant but RNA synthesis reached the same level as in the controls or even surpassed it. In plants to which THY was applied at a time when it was no longer possible to reverse flowering, the results obtained from different experiments were not identical. In some experiments nucleic acid synthesis remained lower than in the variant in which THY restituted flowering. In other experiments nucleic acid synthesis was fully restituted and reached the same level as in the control variant. This phenomenon is explained by the different size of the experimental plants at the beginning of the different experiments. The results are discussed with respect to the relation of the dynamics of nucleic acids to growth and development of the plants.
TL;DR: It was confirmed that oscillations are a result of elongation; the extent of oscillations is quantitatively dependent on the growth rate.
Abstract: The analysis of diurnal oscillatory movements of tobacco leaves was used in the diagnosis of viral infection of plants. The oscillatory helices circumscribed by a growing leaf of a healthy plant were regular, but some deviations, particularly in the transition points, were recorded.
TL;DR: NEU was found to be a relatively suitable mutagen for the chlorococcal algae studied, characterized by the increase in the frequency of cell divisions which yielded a lower number of autospores.
Abstract: Three strains of three different species of chlorococcal algae(Chlorella kesslerii Scenedesmus quadricauda andScenedesmus obliquus) were compared in their physiological and genetical responses to N-ethyl-N-nitrosourea (NEU). The mutagen was applied in the basic doses corresponding to their specific tolerance to it. Exponentially-graded doses derived from the basic ones acted for the same period of time and single basic doses acted at linearly-increased periods of time in parallel experiments. The influence of the mutagen on the cell cycle just in progress was characterized by the increase in the frequency of cell divisions which yielded a lower number of autospores. The conditions of the cells during the first three days after treatment were determined according to the average increase of their lag phase. The relative toxicity of the mutagen was expressed as the survival frequencies. The mutation effects were evaluated according to the frequency of permanent changes observed in the growing cell colonies : lethal, morphological and pigmentation. NEU was found to be a relatively suitable mutagen for the chlorococcal algae studied.
TL;DR: By comparing maize plants cultivated in standing nutrient solution with those from solutions flowing at different flow rates, it has been established that absorption of nitrogen, potassium and especially of phosphorus was increased owing to the flow as mentioned in this paper.
Abstract: By comparing maize plants cultivated in standing nutrient solution with those from solutions flowing at different flow rates it has been established that absorption of nitrogen, potassium and especially of phosphorus was increased owing to the flow There was likewise a relative rise in the distribution of nutrients to the overground parts of the plants The content expressed per unit dry matter was increased only in the case of phosphorus; with nitrogen and potassium it was slightly lower than in the standing solution Increasing amounts of iron were required under the conditions of flowing nutrient solutions to prevent chlorosis of the plants The production of dry matter,NAR andRGR was also increased because of the flow The flow considerably changed the habitus of the primary roots of the maize plants The roots were longer, thinner and on the whole they contained relatively less dry matter (RWR) The lengthening of the roots is explained as a response to stimulation by the solution flow—the rheotropism