Diurnal and ultradiurnal oscillations of growing organs within the framework of the information system of the plant

M. Spurný, Dana Konečná

Biologia plantarum 20:241-247, 1978 | DOI: 10.1007/BF02922677

The analysis of growth and movements of seedling organs of kidney bean (Phaseolus vulgaris L.) provides a pattern of periodic phases of activity and relaxation. The existence of a central organ which would control the phase relationships, is not anticipated in the integrity of the plant. The cyclic activity of individual organs shows itself by growth associated with oscillation movements. One and the same organ may simultaneously accomplish oscillatory movements with a diurnal and ultradiurnal frequency. These rhythms originate during the organ development; the first pair of kidney bean leaves at first executes oscillation movements with a diurnal...

Book Review

Ingrid Tichá

Biologia plantarum 20:247, 1978 | DOI: 10.1007/BF02922678

Mathematical description of nitrogen and phosphorus accumulation in developing barley kernels

L. Nátr, P. Apel, Ivaka Kousalová

Biologia plantarum 20:248-255, 1978 | DOI: 10.1007/BF02922679

The changes of kernel nitrogen (N), phosphorus (P) and dry weight (DW) were determined during the time period from 10 days after anthesis till maturity in three spring barley strains. The plants were cultivated under field conditions in Gatersleben (German D.R.) and Kroměříž (Czechoslovakia). The course of N, P and DW changes was described by Richard's comprehensive growth function dW/dt = aW^m + bW, where W is the amount of N, P or dry matter per kernel, a, b, m are coefficients. The integral of this function was used and several parameters calculated. There was a remarkable synchrony between N or P and total dry matter accumulation in the...

Changes in drought resistance in the course of rape hypocotyl growth

Hanna Obłój, Alina Kacperska-Palacz

Biologia plantarum 20:256-261, 1978 | DOI: 10.1007/BF02922680

The winter rape hypocotyls grown in darkness or in light were found to differ markedly both in the elongation rate and in the sensitivity to desiccation. Light arrested the elongation of hypocotyls and markedly increased their resistance to desiccation. It was found that the former effect was due to 2 factors: better avoidance of water stress and higher desiccation tolerance in the light-treated tissue. Comparison of WSD (waret saturation deficit) and water potential developed by 5 day-old hypocotyls subjected to different degrees of desiccation indicates that better water relations in the light-grown tissues might be due to the decreased elasticity...

Re-examination of electrical conductivity method for estimation of drought injuries

Ewa DŁugokęcka, Alina Kacperska-Palacz

Biologia plantarum 20:262-267, 1978 | DOI: 10.1007/BF02922681

The determination of electrolyte leakage from the winter rape hypocotyls subjected to desiccation over C_aCl₂ under vacuum was found to be the proper and useful method for the estimation of the direct, water stress-induced injuries in the plant tissue. The described procedure of desiccation allows a differentiation between the tissue drought tolerance and the tissue ability to avoid water stress.

Book Review

Ingrid Tichá

Biologia plantarum 20:267, 1978 | DOI: 10.1007/BF02922682

Assessment of radiosensitivity from the germination of jute seeds

N. Ghosh, S. Sen

Biologia plantarum 20:268-273, 1978 | DOI: 10.1007/BF02922683

Irradiation with X-rays and gamma rays reduced the speed of germination of seeds of jute cultivars,viz., JRO 632, JRO 620, Sudan Green ofCorchorus olitorius and JRC 212, Fanduk, D 154 ofC. capsularis. Though the first phase of germination(i.e. seed variability) remained apparently unaffected, the second phase (i.e. the sprouting ability) and the third phase(i.e. the attainment of autotrophic status) were found to be the best indicators of radiation injury and provided dependable data for the assessment of radiosensitivity.
The jute cultivars have not shown accountable intervarietal differences in radiosensitivity...

Book Review

Ingrid Tichá

Biologia plantarum 20:273, 1978 | DOI: 10.1007/BF02922684

Benzylaminopurine induced changes in photosynthesis and photorespiration of barley plants

C. Passera, A. Albuzio

Biologia plantarum 20:274-280, 1978 | DOI: 10.1007/BF02922685

Benzylaminopurine (BA) caused an enhancement of chlorophyll and protein content and a reduced elongation of primary barley leaves. BA did not change the rhythmic pattern of¹⁴CO₂ fixation and activities of RuBP carboxylase, RuBP oxygenase, glycolate oxidase and phosphoglycolate phosphatase, but the enzyme activities were enhanced and the level of¹⁴CO₂ fixation was reduced. Light/dark¹⁴CO₂ evolution ratio was affeoted by BA only in older leaves. BA acts sequentially on the activities of photosynthetic and photorespiratory enzymes.

Photocontrol of germination of cucumis anguria l

Ailema Noronha, Marly Vicente, G. M. Felippe

Biologia plantarum 20:281-286, 1978 | DOI: 10.1007/BF02922686

Germination ofCucumis anguria was inhibited by white, blue (B), and far-red (FR) irradiation and promoted by darkness and red (R) irradiation. The effect of white light was greater when supplied after rather than before the dark period. Darkness was more effective in reversing the effect of FR than FR in reversing the effect of darkness. FR was also more effective than B. When darkness followed B pretreatments, final germination percentage was higher than with FR pretreatment. R fully reversed the inhibitory effect of FR.

Book review

T. Gichner

Biologia plantarum 20:286, 1978 | DOI: 10.1007/BF02922687

Relationship between stomatal frequencies, yield components and morphological characters in collections of winter wheat cultivars

J. F. Ledent, M. F. Jouret

Biologia plantarum 20:287-292, 1978 | DOI: 10.1007/BF02922688

Genotypes on the Belgian national list as well as about 120 genotypes of winter wheat from the world collection were examined for the relationships of their stomatal frequencies in the flag leaf with yield, yield components and other morphological characters. Stomata were in rows, with a higher density in adaxial leaf surface. Cultivars differed significantly in both stomatal density and number of rows of stomata per unit of leaf width. Yield and morphological characters in general showed no significant correlation with stomatal frequencies. Densities in all series examined ranged from 46 to 78 stomata per mm² in the adaxial leaf epidermis...

The sequence and duration of mitotic cycles in the apical root meristem ofVicia faba l

A. Muhín, Mária Luxová

Biologia plantarum 20:293-298, 1978 | DOI: 10.1007/BF02922689

A study was made on the mitotic cycle times in meristematic cells of Vicia faba root tips and on the relationship between their duration and the position of a certain cell in the column of proliferating cells. For the demonstration of the sequence and duration of mitotic oycles a single-column model was used. The results of experiments show that the great variability in the duration of mitotic cycles (from 12 to l20 h)is the result of a different program of the apical meristem cells. The long duration of the cycle of initials corresponds to the sum of cycle times of their descendants.

Book review

Ingrid Tichá

Biologia plantarum 20:298, 1978 | DOI: 10.1007/BF02922690

The Role of Endogenous Abscisic Acid in the Correlation Between the Cotyledon and Its Axillary Bud in PeaPisum sativum L

J. Šebánek, J. Hradilík

Biologia plantarum 20:299-302, 1978 | DOI: 10.1007/BF02922691

On cutting off one cotyledon from decapitated pea seedlings cultivated in the dark, the apical dominance is restored, as is well-known, by the growth of the bud of the removed cotyledon. As early as 12 h following cotyledon amputation(i.e. at the time when buds of both cotyledons-remaining and removed-are not yet differentiated in size), a decrease in the level of endogenous abscisic acid can be demonstrated in the bud of the removed cotyledon.

Book reviews

J. Krekule, Z. Opatrný, T. Gichner, M. Kamínek

Biologia plantarum 20:303-304, 1978 | DOI: 10.1007/BF02922692