Methylation patterns of two repetitive DNA sequences in tobacco tissue cultures and their regenerants

B. Vyskot, B. Gazdová, J. ©iroký

Biologia plantarum 35:321, 1993 | DOI: 10.1007/BF02928504  

DNA methylation of two repetitive sequences in tobacco nuclear genome was studied in the course ofin vitro dedifferentiation and differentiation. Using 5-mC sensitivè restriction enzymes and DNA/DNA hybridization with 25S-rDNA probe it has been shown that during the early phase of callus induction prominent changes in the methylation pattern occur which are stably maintained during subsequent callus growth. The following protoplast recovery and plant regeneration have again displayed some more modifications of the methylation status. Comparing the patterns of R₀ plants with the original plant material and the calli it can be...

Book review

T. Gichner

Biologia plantarum 35:328, 1993 | DOI: 10.1007/BF02928505  

Effect of anti-microtubular drug amiprophos-methyl on somatic embryogenesis and DNA ploidy levels in alfalfa and carrot cell suspension cultures

P. Binarová, J. Dole¾el

Biologia plantarum 35:329-339, 1993 | DOI: 10.1007/BF02928506  

A short treatment with the anti-microtubular drug amiprophos-methyl (APM) blocked somatic embryogenesis in alfalfa(Medicago sativa L.) and carrot (Daucus carota L.). The interruption was temporary and restoration of somatic embryogenesis was observed in long-term cultures. In addition to the effect on somatic embryogenesis, APM treatment induced polyploidization the extent of which was concentration dependent. In long-term alfalfa cultures, APM-induced loss of somatic embryogenesis led to ploidy instability and to a shift to DNA aneuploidy. Critical stages of somatic embryogenesis sensitive to disruption of microtubule-mediated processes...

Book review

J. POSPÍ©ILOVÁ

Biologia plantarum 35:340, 1993 | DOI: 10.1007/BF02928507  

Changes in fatty acids contents and growth characteristics in transformed oilseed rape (Brassica napus)

J. Dusbábková, I. Boháèová, L. Bezecná, M. Konrádová, J. Neèásek

Biologia plantarum 35:341-348, 1993 | DOI: 10.1007/BF02928508  

Spring oilseed rapeBrassica napus L. ssp.oleifera cv. HM-81 was transformed with T_L-DNA of the Ri plasmid of the agropine strainAgrobacterium rhizogenes 15834. Selfed progenies (R₂ and R₃ generations) were studied for changes in values of growth characteristics and fatty acids contents. Transformants are 'homozygous' for T_L-DNA. Both generations of transformants differed significantly from the nontransformed control plants in reduced length, lower number of pods per plant, lower total mass of seeds and the higher number of branches. The contents of palmitic, linoleic and linolenic acids...

Differences in the synthesis of total and poly(A)⁺RNA in the Kennebec potato and its dihaploid

M. K. Cross, W. J. Kaczmarczyk, R. J. Young, V. Ulrich

Biologia plantarum 35:349, 1993 | DOI: 10.1007/BF02928509  

RNA synthesis as measured by the incorporation of tritiated uridine into trichloroacetic acid insoluble material was studied in the leaf protoplasts of cv. Kennebec and its parthenogenically derived dihaploid. Protoplasts of cv. Kennebec incorporated tritiated uridine at a greater rate and accumulated more than twice the amount of radioactive materials than did the dihaploid over a 6-h incubation period. Poly(A)⁺RNA, isolated from the total RNA of the tetraploid and of the dihaploid, by oligo(dT)-cellulose column chromatography, was present in amounts of 11.3 and 5.2 % respectively. The tetraploid synthesized 4.8 times the amount of poly(A)⁺RNA...

Karyotype diversity and interspecific 4C DNA variation inBupleurum

A. B. Das, R. Mallick

Biologia plantarum 35:355, 1993 | DOI: 10.1007/BF02928510  

Investigation on karyotype, 4C nuclear DNA amount and interphase nuclear volume (INV) of different HimalayanBupleurum species belonging toUmbelliferae revealed genetic differentiation. Numerical and structural alternation of chromosomes in interspecific level were manifested in their statistically significant altered species specific 4C nuclear DNA content. Somatic chromosome number ranged between 2n = 14 and 2n = 16.B. himalayense was reported for the first time having 2n = 16 chromosomes. Correlation coefficient among the various chromosomal and nuclear parameters showed no significant progressive or regressive interdependence...

Book review

J. POSPÍ©ILOVÁ

Biologia plantarum 35:364, 1993 | DOI: 10.1007/BF02928511  

Absorption of sucrose by tissues of adult tubers of potato(Solatium tuberosum L.). modalities and influence of phytohormones

M. Penot, A. Hourmant, A. Reddahi

Biologia plantarum 35:365, 1993 | DOI: 10.1007/BF02928512  

Sugar uptake by potato tuber discs was studied. Discs were used "fresh" or after a 24-h ageing period. It was shown that ageing increases (by 3 to 4 times) the rate of glucose and sucrose uptake. Sucrose uptake by fresh tissues was insensitive to the presence of glucose or fructose while a competitive effect was observed after ageing. This indicates the development of an invertase activity, which was inhibited by tris-buffer. Sucrose and glucose uptake by aged discs was dependent on cellular metabolism as shown by the sensitivity to low temperature and metabolic inhibitors (NaCN, DNP, CCCP). Involvement of thiol groups was demonstrated by the inhibition...

Rapid micropropagation of a tree of arid forestryAnogeissus acuminata

T. S. Rathore, N. S. Deora, N. S. Shekhawat, R. P. Singh

Biologia plantarum 35:381-386, 1993 | DOI: 10.1007/BF02928513  

Multiple shoots (16-20 shoots per expiant) were induced from cotyledonary node region ofAnogeissus acuminata (Roxb. ex DC.) Guill. & Perr. on Murashige and Skoog's (MS) medium containing IAA 0.1 mg 1^-1 + BAP 1.5 mg 1^-1 and ascorbic acid 50 mg 1^-1, citric acid 25.0 mg 1^-1, arginine 25 mg 1^-1 and adenine sulphate 25 mg 1^-1. From the first node of seedling only 4-6 shoots per expiant were proliferated. Segments ofin vitro produced shoots were used as expiants for further multiplication of shoots upto 16 successive cultures at an interval of 4 week on MS medium with IAA...

Changes in the levels of free IAA and cytokinins in potato tubers during dormancy and sprouting

L. S. Sukhova, I. MachÁÈkovÁ, J. Eder, N. D. Bibik, N. P. Korableva

Biologia plantarum 35:387, 1993 | DOI: 10.1007/BF02928514  

Changes in the levels of free indol-3-ylacetic acid (IAA) and free cytokinins were determined in the course of dormancy and sprouting period in potato tubers(Solanum tuberosum L., cv. Nevskii) stored at 4 °C. The same analyses were performed in potato tubers after Ethrel application, which prolongs dormancy. No significant changes were found in free IAA level during dormancy followed by a rapid decrease during sprouting. After Ethrel application a significant lower IAA level was found 3 weeks after application, but further on no changes in free IAA level between treated and non-treated tubers were detected. Cytokinin level was relatively low...

Book review

I. MachÁÈkovÁ

Biologia plantarum 35:392, 1993 | DOI: 10.1007/BF02928515  

Photosynthesis and water relations in transgenic tobacco plants with T-DNA carrying gene 4 for cytokinin synthesis

J. Èatský, J. Pospí¹ilová, I. Macháèková, N. Wilhelmová, Z. ©esták

Biologia plantarum 35:393, 1993 | DOI: 10.1007/BF02928516  

Expression of the gene 4 for cytokinin synthesis in two clones of transgenic tobacco plants resulted in slightly higher(ca. 10 - 20 %) levels of endogenous cytokinins -zeatin, zeatin riboside and isopentenyladenosine. This was associated with changes in photosynthetic processes on chloroplast and leaf level. In comparison with nontransformed plantlets a higher degree of grana stacking was found in both clones of transgenic plants which indicated a higher proportion of photosystem 2 lightharvesting complex in thylakoids. This was supported by a decreased chlorophylla/b ratio in the separated grana fraction. The rate of leaf net photosynthetic...

Book review

J. JenÍk

Biologia plantarum 35:400, 1993 | DOI: 10.1007/BF02928517  

Differential responses of N-nitrosoamines and aromatic amines in the plant cell/microbe coincubation assay

T. Gichner, E. D. Wagner, M. J. Plewa

Biologia plantarum 35:401-406, 1993 | DOI: 10.1007/BF02928518  

The plant cell/microbe coincubation assay is based on employing living tobacco cells in suspension culture as the activating system for promutagens and the Ames/Salmonella cells as the genetic indicator system. In contrast to aromatic amines(e.g. 2-aminofluorene andm-phenylenediamine) that were previously reported to be activated to products mutagenic in theS. typhimurium strains TA98 or YG1024 by tobacco cells, promutagenic N-nitrosoamines (N-nitrosodimethylamine, N-nitroso-morpholine, N-nitrosopiperidine, N-nitrosomethyl-2-hydroxypropylamine) were not activated to product(s) mutagenic inS. typhimurium TA 100.

Ultrastructure of chloroplasts of pine needles exposed to an industrial environment

R. González, A. Segura, M. L. González

Biologia plantarum 35:407, 1993 | DOI: 10.1007/BF02928519  

In one- and two-year-old green needles ofPinus pinaster growing downwind from a coal-fired power station (main airborne pollutant SO₂), mesophyll chloroplast alterations consisted in swelling of the lamellae (ranging in intensity from slight to pronounced), reduction of grana number, and granulation of the stroma. The most severely affected chloroplasts were almost spherical, with highly dilated and corrugated lamellae and lacunae in the stroma. There was a large increase in the amount of lipid-like material present as droplets in cytoplasm, vacuole and stroma chloroplasts; these droplets appeared to be expulsed from the chloroplasts...

Effects of salinity on growth and metabolism ofPhaseolus vulgaris

M. E. Younis, M. A. Abbas, W. M. Shukry

Biologia plantarum 35:417, 1993 | DOI: 10.1007/BF02928520  

Increasing salinity induced a marked reduction in the plant growth, thoughPhaseolus seedlings tolerated salinity up to 120 mM NaCI. A great reduction in sugar and protein contents occurred with increasing salinity, whereas soluble nitrogen compounds and the relative contents of the photosynthetic pigments were increased in the treated plants. Increasing Ca concentration in the salinized medium appeared to improve the plant growth and to increase the contents of saccharides and proteins in the NaCl-treated plants. This suggests that Ca could be added to salinized media to overcome the deleterious effects of salinity on the growth and productivity...

Physiological and biochemical aspects of tolerance of three grass species to varying Na⁺/Ca²⁺ ratios

M. Ashraf, M. I. Naqvi, Z. U. Zafar

Biologia plantarum 35:425, 1993 | DOI: 10.1007/BF02928521  

The effects of decreasing Ca²⁺ concentrations (Na/Ca ratios were 24, 49, 99 and 199) of the saline growth medium (NaCl concentration 200 mM) on three grass speciesCenchrus pennisetiformis Hochst. & Steud,Leptochloa fusca L. Kunth. andPcmicum turgidum Forssk. were assessed after 7 weeks growth in sand culture.L. fusca produced the highest dry biomass of all the species at varying Na/Ca ratios. Number of tillers per plant and number of green leaves per tiller were reduced significantly only inC. pennisetiformis. Leaf water potential ofC. pennisetiformis decreased at all external Na/Ca ratios, whereas...

Book review

P. Tlusto¹

Biologia plantarum 35:434, 1993 | DOI: 10.1007/BF02928522  

Lipid and fatty acids composition of photoautotrophically and heterotrophically grownChlamydomonas reinhardtii

M. M. El-Sheekh

Biologia plantarum 35:435, 1993 | DOI: 10.1007/BF02928523  

Monogalactosyl diacylglycerol (MGDG), digalactosyl diacylglycerol (DGDG), phosphatidylglycerol (PG), phosphatidylethanolamine (PE), phosphatidylinositol (PI) and sulfoquinovosyl diacylglycerol (SQDG) are the most abundant lipid classes present in both the autotrophically and heterotrophically grownChlamydomonas reinhardtii. However, phosphatidylcholine (PC) and diacylglycerol (N,N,N-trimethyl)-homoserine (DGTS) were absent in both alga types. The polyne index B was higher in heterotrophic than photoautotrophic algae, but the unsaturation index was higher in photoautotrophic algae PI, PE and DGDG. The proportion of linolenic acid decreased...

Mercury-tolerance ofChloris barbata Sw. andCyperus rotundus L. isolated from contaminated sites

M. Lenka, B. L. Das, K. K. Panda, B. B. Panda

Biologia plantarum 35:443-446, 1993 | DOI: 10.1007/BF02928524  

Chloris barbata Sw. andCyperus rotundus L. from a mercury contaminated site near a chloralkali plant were tested for relative tolerance to Hg by root-elongation method. The above two species from the Hg-contaminated site exhibited high tolerance to Hg compared to the same species from a non-contaminated site. Tolerance to Hg was higher inChloris barbata than inCyperus rotundus.

Flowering and male reproductive functions of chickpea (Cicer arietinum L.) genotypes as affected by salinity

H. R. Dhingra, T. M. Varghese

Biologia plantarum 35:447, 1993 | DOI: 10.1007/BF02928525  

The influence of salinity, given at germination (stage I) or 75 d after sowing (stage II), on flower production and characteristic features of male reproductive structures was studied in three promising genotypes of chickpea (Cicer arietinum L. cv. ICCV 88102, H 82-2 and C-235). In ICCV 88102 and H 82-2 salinity 20 meq 1^-1 increased the number of flowers when applied at both stages whereas in C-235 only when applied at the later stage. The salinity also delayed flowering; the higher salinity the greater was delay in flowering. In H 82-2 and C-235 salinity treatment given at stage II (when few flower buds appeared) hastened the flowering....

Effect of Zn²⁺ on water and K⁺ fluxes in detopped maize plants

M. A. Abbas

Biologia plantarum 35:453-459, 1993 | DOI: 10.1007/BF02928526  

Water and K⁺ fluxes were examined in detopped plants ofZea mays L. (cv. White Horse Tooth), which were grown and exuded on half-strength Long Ashton nutrient solution containing the appropriate concentration of Zn²⁺ at 20 °C. In light-grown plants, 100 and 500 μM Zn²⁺ increased both water and K⁺ fluxes in detopped maize plants whereas 1 000 μM Zn²⁺ inhibited both fluxes. In the dark-pretreated plants, 1 000 μM Zn²⁺ in the medium stimulated K⁺ flux. The fluxes of K⁺, Zn²⁺, Ca²⁺ and Mg²⁺ were usually higher in detopped...

Vanadium bioaccumulation inPisum sativum seedlings

W. Nowakowski

Biologia plantarum 35:461, 1993 | DOI: 10.1007/BF02928527  

Vanadium bioaccumulation calculated as the ratio of its content in plant biomass to that in the substrate (Vbi-index) was studied in pea. Vbi was on average 11.275, 11.770 and 13.153 in the roots, and 0.809, 0.467 and 0.749 in the shoots of the cultivars Opal, Laser and Ramir, respectively. This indicates cultivar differences in vanadium uptake, and low translocation rates from roots to shoots. Vanadium (3 to 30 mg 1^-1) decreased shoot and root fresh and dry masses of the three cultivars. Seedlings of the cv. Opal were the most susceptible to higher concentrations of vanadium (20 to 30 mg 1^-1), whereas seedlings of cv. Laser were...

Effect of gibberellic acid on stomatal diffusive resistance and photosynthesis in waterlogged peanut plants

N. R. Bishnoi, H. N. Krishnamoorthy

Biologia plantarum 35:467, 1993 | DOI: 10.1007/BF02928528  

Plants of peanut (Arachis hypogaea L.) were subjected to 7-d and 14-d waterlogging and sprayed with 10 and 100 mg 1^-1 of gibberellic acid (GA₃). Waterlogging decreased the leaf area (A), net photosynthetic rate (P_n), chlorophyll content (Chi) and temporarily the leaf water potential (Ψ_w) and increased stomatal diffusive resistance (r_s) of both leaf surfaces. Application of GA₃ increased A and P_n and significantly decreased the r_s of both leaf surfaces but did not affect Ψ_w or Chl. Thus GA₃ partially alleviated the effects of...

Utilization of exogenously supplied primary precursors for essential oil synthesis in cymbopogon species

R. Luthra, R. S. Sangwan, N. Singh-Sangwan

Biologia plantarum 35:473-476, 1993 | DOI: 10.1007/BF02928529  

The relative efficiency of incorporation of the exogenously supplied primary precursors [2-¹⁴C]acetate, [U-¹⁴C]glucose and [U-¹⁴C]sucrose into essential oil was determined in the immature leaves of threeCymbopogon species(C. martinii,C. winterianus andC. flexuosus). Acetate was most efficiently incorporated into essential oil inC. winterianus andC. flexuosus, whereas glucose was the best precursor inC. martinii. The observations are consistent when expressed as radioactivity [Bq] of essential oil per leaf, as percent incorporation or moles of precursors utilized for essential...