Biologia plantarum, 1971 (vol. 13), issue 2

Article

Transport and localization of 6-(γ,γ-dimethylallylamino)-purine-8-¹⁴C cytokinin in apple trees

L. Chvojka, J. Stohr, Libuše Hejmová, J. Beneš

Biologia plantarum 13:65-68, 1971 | DOI: 10.1007/BF02936822

When cytokinin 6-(γ,γ-dimethylallylamino)-purine-8-¹⁴C was injected into the side root of a one-year-old apple graft, variety Cox's Orange Pippin, it was mainly transported acropetally, but a certain part of the radioactivity was also transported basipetally into the root below the place of injection. 6 days after application of the labelled cytokinin most of the radioactivity was detected in the xylem, 20-30 cm above the place of application. An appreciable quantity of radioactivity was transported toward the apical part of the plant as far as 100 cm from the point of application. Special analysis showed that 6 days after exposition...

Contribution to the study on the reparative effect of exogenous DNA in the irradiated meristem ofVicia faba

Jana Šlotová, Z. Karpfel, Dagmar Kubíčková

Biologia plantarum 13:69-78, 1971 | DOI: 10.1007/BF02936823

The present report is focused on the study of participation of exogenous DNA in the process of postirradiation reparation of meristematic cells ofVicia faba primary roots. It is aimed at comparison of the positive reparative effect of isologous DNA with postirradiation action of heterologous DNA in its native, thermally denatured and DNAase-degraded forms, or DNA degraded by ultrasound, and with the effect of other biologically important macromolecules (RNA, histone, heparin, and dextran sulphate). For this purpose, the roots ofVicia faba irradiated by 150 r exposure were cultivated in solutions containing the above substances for an...

Concerning variability in the delimitation of the vascular system in root primordia of maize embryos

Mária Luxová

Biologia plantarum 13:79-87, 1971 | DOI: 10.1007/BF02936824

1. The transfer of immature embryos from maternal plants to artificial media influenced the radial arrangement of vascular bundles in developing root primordia. The variability in the number of poles of the prospective protoxylem and protophloem, observed as a rule during embryogenesis under natural conditions, could not be suppressed even under the conditions ofin vitro cultivation. The possibility is admitted that when using agar medium the nutrient supply need not necessarily be equivalent for all embryos.
2. Using excised embryos of various ages the period of delimination of the vascular system in the root primordium was determined. It...

Heat-treatment dependent dormancy in seeds of Psoralea corylifolia Linn.

S. P. Shukla

Biologia plantarum 13:88-99, 1971 | DOI: 10.1007/BF02936825

The intact seeds ofPsoralea corylifolia which are actieually one-seeded fruit, presents a unique problem of dormancy. Germinability of these dormant seeds is not enhanced as a result of a number of treatments: 1) Dry-storage of 44 months under moderate conditions of the laboratory. 2) Periodic germination in different months of the year. 3) Immersion in ethylalcohol (70% and 100%), hydrogen-peroxide, nitric acid, acetone, ether solvent and hydrochloric acid. 4) Removal of pericarp.
Four distinct methods have also been evolved which effectively overcome the dormancy of the seeds: 1) Mechanical puncturing of seedcoverings. 2) Sulphuric acid...

Nativity of the macromolecule of isologous DNA as a condition for its reparative effect on radiation damage

Jana Šlotová, Z. Karpfel, Dagmar Kubíčková

Biologia plantarum 13:100-109, 1971 | DOI: 10.1007/BF02936826

The effect of isologous DNA on the course of postirradiation reparation of meristematic cells ofVicia faba primary roots was studied in detail. A considerable interest was devoted to determinations of fundamental qualitative and quantitative conditions of the above effect of isologous DNA. Main criteria of the effect were both mitotic activity of irradiated cellular population and dynamics of chromosome aberrations induced by radiation. One set of experiments compared the course of reparation as occurred in regard to applied dose of ionizing radiation in native isologous DNA, DNA denaturated by heat and degraded by DNAase, and post-irradiation...

Histogenesis and localization of non-specific esterase in root tip

K. Beneš

Biologia plantarum 13:110-121, 1971 | DOI: 10.1007/BF02936827

A procedure was developed for satisfactory freeze-sectioning of root tips. The use of Ca formol-fixed material kept and frozen in Holt's syrup is recommended. The existence and different localization of 2 fractions of non-specific esterase was verified in root tips ofVicia faba. The same results were revealed in fixed and unfixed material. The dynamics ofin situ reaction was followed with respect to optimal incubation time. The results with substrates of different chain length support the existence of 2 fraction of the studied enzyme, none of which, concerning substrate specificity, is a lipase. It follows from the present studies inVicia...

The interaction of abscisic acid with growth stimulators in germination of partially after-ripened apple embryos

R. Rudnicki, W. Kamiński, Janina Pieniążek

Biologia plantarum 13:122-127, 1971 | DOI: 10.1007/BF02936828

The effect of abscisic acid (ABA), gibberellin A₄₊₇ and benzyladenine on germination of apple embryos which had been stratified for different periods of time was investigated.
The growth stimulators accelerated the germination of non-stratified embryos or those stratified for a short time. After a longer period of stratification, the effect of growth stimulators was visible only when germination of the embryos was artificially inhibited by simultaneous application of synthetic ABA.
The sensitivity of stratified apple embryos to the exogenous ABA diminished with the number of hours elapsed between the imbibiting by the embryos of the...

Some growth responses of apple seedlings to abscisic acid and growth stimulators

W. Kamiński, R. Rudnicki, Janina Pieniążek

Biologia plantarum 13:128-132, 1971 | DOI: 10.1007/BF02936829

Antonovka seedlings were obtained from the embryos soaked in abscisic acid (ABA) alone, gibberellin A₄₊₇, benzyladenine or the mixtures of these regulators. The inhibitory effect of ABA on the growth of the seedlings was of temporary duration. The height of the 12 week-old seedlings was dependent only on the degree of seed after-ripening and not on the ABA treatment.
The growth stimulators studied were unable to overcome the inhibitory effect of ABA observed in the early stages of seedling growth. The growth stimulators did not substitute, for cold treatment of apple seeds which is the only treatment so far known to overcome the dwarf...

Influence of 4-phenylpyridine on the activity of some enzymes catalyzing the glyeide catabolisme ofSynapis alba seedlings

Olga Makovcová, L. Šindelář, P. Vaculík

Biologia plantarum 13:133-140, 1971 | DOI: 10.1007/BF02936830

4-phenethylpyridin favours pentose cycle in glycide degradation inSinapis alba seedlings. The influence of the tested compound on following enzymes: hexokinases, saccharase, phosphorylase, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, phosphoglucomutase and phosphoglucoisomerase was studied. In roots of treated seedlings a substantial increase of pentose cycle enzymes was found together with the corresponding increase in glycide content. The increased activity of phosphoglucomutase may be explained by the chromatographically detected presence of stachyose in the seeds which as the source of galactose enables the formation...

Brief Communications

Bimodal climacteric respiration of postharvest pear and tomato fruit stored at low relative humidity

N. F. Haard

Biologia plantarum 13:141-144, 1971 | DOI: 10.1007/BF02936831

Tomato and pear fruit underwent shifts in respiratory metabolism (CO₂ evolution) when ripened at reduced relative humidity (15 to 25% R.H.). A bimodal respiratory spectrum was observed with fruit ripened at low relative humidity; concomitantly, a number of the ripening indices were observed to quantitatively (mainly intensification) and perhaps qualitatively differ from fruit ripened at 80 to 90% R.H. The results suggest that the additional climacteric respiratory burst is coupled to metabolic changes associated with ripening and illustrate the dramatic influence water vapor deficit can have on physiological processes such as ripening.