The influence of 6-benzylaminopurine on the respiration of apple buds of the Boskoop variety for 5 days after application of kinine was observed. It was discovered that the consumption of oxygen determined by the direct method of Warburg is higher from the first day after application of 6-benzyl-amonipurine and the increase is continually more marked up to the fifth day, when the consumption of oxygen in stimulated buds is 75 per cent higher than in the control buds.

Wenn wir die Keimwurzeln der Puffbohne (Vicia faba L.) chloralisieren und später die Seitenwurzeln untersuchen, die in ihren chloralisierten Zonen entstanden, sehen wir, dass sich alle in einem verschiedenen Grade der Mixoploidie befinden (Němec 1961). Nach einer fünffachen Chloralisierung enthielten sie allermeist etwa bis zu einem Drittel polyploide Zellen, doch gibt es auch Vegetationsspitzen, die bis zu vier Fünftel polyploide Zellen enthalten. Die Zellen der Wurzelspitzen der Puffbohne ertragen unter dem Einfluss der Chloralisierung eine Erhöhung der Chromosomenzahl nur etwa auf 32n; solche Zellen können sich noch einigemale teilen, dann aber sterben sie früher oder später ab. Eine Restitution der mixoploiden Wurzelspitzen, sei es nun nach einer Dekapitierung oder nach einem Längsschnitt in die Vegetationsspitzen, geht normal vor sich und es beteiligen sich an ihr harmonisch diploide wie polyploide Zellen. Es ist nicht beobachtet worden, dass die polyploiden Zellen vielleicht aus dem Restitutionsvorgang ausgeschlossen worden wären oder dass es zu unregelmässigen Wucherungen gekommen wäre. Die mixoploide Spitze verhält sich bei der Restitution wie ein ganzes, einheitliches, lebendes Organ.

The cluster bases (bourses) in each case had a higher content of total nitrogen and both absolute and relative soluble organic nitrogen than the new secondary growth of cluster bases on trees both with fruit and without fruit than new spurs on trees with fruit. This higher content of total and soluble nitrogen is primarily a feature of the organ and has no connection with the initiation of flower buds. The secondary growth of cluster bases on the trees with fruit never had a significantly higher content of soluble nitrogen than the new secondary growth of cluster bases and new growth of spurs on trees without fruit. In all apple varieties observed the same qualitative pattern of free amino acids and amides was determined and a similar ratio of free amino acids and amides in the corresponding axial parts. The highest amount of free amino acids and amides-especially asparagine and arginine-was determined in the cluster bases. Arginine was accumulated in large quantities in the cluster bases much earlier than in the secondary growth of cluster bases or in the new growth of spurs. An accumulation of arginine and asparagine occurred in the cluster bases even when the supply of nitrogen was insufficient, in the secondary growths of cluster bases, however, their content was very low during nitrogen deficiency. The content of glutamine and sometimes threonine in cluster bases with fruit was also considerably increased. There was more glutamic acid, glutamine and sometimes threonine too in younger axils than in older ones already lignified.
From results given in this work it can be concluded that there is no obvious relation between the content and proportion of soluble and insoluble nitrogen in the spurs of apple trees on the one hand and the initiating of flower buds on the other. Neither was any obvious relation determined between the content of free amino acids and amides in the axillary parts of apple trees under observation and the initiating of flower buds.

The results are discussed of a quantitative and qualitative analysis of the protein characters of seed-enclosed cotyledons and of hypocotyls + roots (of the primary root) of germinated seeds of the following species:Phaseolus vulgaris L.,Phaseolus coccineus L.,Phaseolus lunatus L.,Phaseolus aureus Roxb.
1. A practically identical phaseolin was found in the cotyledonsof Phaseolus vulgaris L. andPhaseolus coccineus L., being absent inPhaseolus lunatus L. andPhaseolus aureus ROXB.
2. A protein component described as Phaseolus protein III was found in the hypocotyl + root ofPhaseolus vulgaris L.,Phaseolus coccineus L. andPhaseolus lunatus L.; it was absent inPhaseolus aureus Roxb.
3. The inequality of breadth of taxonic (group) specificity of the protein characters has been confirmed anew. This fact is discussed in connection with the relative phylogenetic age of the characters, On the basis of the results obtained a developmental scheme of the studied species is proposed.

The indirect influence of irradiation on the production of anthocyanins in the blossoms of red balsam (Impatiens balsamina L.) was investigated. After 18 hrs. of swelling, seeds were irradiated with 4560 r and then changes in the anthocyanin content of blossoms were examined. In X₀ three out of four lines tested displayed a marked increase in anthocyanin content by 18%, 18% and 29%. In X₁ the quantitative content of anthocyanins either equalled that of the controls or was lower, in X₂ a significant decrease in anthocyanin content in all the lines was observed. We are apparently dealing here with a physiological effect of the type of "prolonged modifications".
In X₁ several plants with pink flowers appeared (3.4%). It is assumed that this is not due to a segregation caused by heterozygous material (the controls did not show this effect) but rather to a recessive mutation brought about by irradiation, which became apparent only in X₁.

1. Suppressors were found in reciprocal crosses of some varieties of barley for the manifestation of recessive and dominant alternatives of the following characters: number of rows of the spike, presence or absence of glumes, character of awns and formation of the spike basis.
2. A proof of the existence of suppressors is presented merely statistically on the basis of segregation ratios in the F₂ generation, in the total F₃ generation and in the individual segregating progenies of plants from the F₂ generation and in the back crosses.
3. It was confirmed that the inheritance of the characters investigated is independent in spite of the fact that the segregation ratios are complicated by the participation of suppressors.
4. Separated cultivation of individual progenies from hybrid seeds formed on the mother plant was shown to be very suitable and efficient in hybridization experiments of this type.
5. The significance of the participation of the suppressors in the inheritance of the characters studied is pointed out with respect to the practical breeding of barley.

The reaction ofSolanum tuberosum L. after the irradiation of isolated sprouts was examined. A dose causing marked changes was sought. After a dose of 1,000 r, deformations began to appear in the tuber and stem, which increased with higher doses. Deformations of the tuber were observed after a dose of 250 r. In hybrids 4/50, nests of red-skinned potatoes were found. This property is partly preserved during the subsequent generation. The material is being further examined.

The effect of CO₂ on the plasmatic structure of root-hairs of wheat and barley and the epidermal cells of onion was observed. The results were evaluated on living material with the aid of phase contrast. The root-hairs of barley and the epidermis of onion react to short exposure to an atmosphere of CO₂ by a cessation in the flow of plasma, a lengthening of the mitochondria and a rounding of the plastids.
When the influence of CO₂ lasts longer, it causes fragmentation of the mitochondria. In this phase the cells recover most quickly from the shock caused by their exposure to CO₂. When the plant is under the influence of CO₂ for too long a time, the effect is lethal. The root-hairs of wheat, which have mainly granulated mitochondria, reacted after only 40 minutes in CO₂ by a rolling-up of all the plasmatic particles.
This observation agrees with the results obtained on permanent preparations in the former work and leads to the conjecture, that by fragmentation of the mitochondria, the cell adapts itself to inhibited respiratory conditions.

1. The differences in the dynamics of the origin and further development of the water saturation deficit (WSD) in leaves of different age from 100- to 120-day-old plants of fodder cabbage and rape were investigated.
2. WSD in leaves of different age detached from plants and wilting without water supply develops most quickly in young and most slowly in old leaves. This is in basic agreement with differences in transpiration rate.
3. When entire plants are cut off, leaves of different age wilt at the same rate. In the later phases of wilting, (i.e. at a WSD value of over 20 to 30%) slightly higher WSD values were found in old leaves.
4. During slow wilting of plantsin situ, induced by decreasing soil moisture, a definite preference of young leaves in water supply was determined commencing from medium WSD values, i.e. on an average from 8 to 20%. During total lack of water in the plant, old and adult leaves wilt markedly and die off; the WSD of young leaves remains for a long time at comparatively low values.
5. In the observed preference of young leaves, the translocation of water to young leaves from the wilting older leaves takes a part.

Po inhibici jarovizace azidem sodnym byla u ozimé pšenice sle dována délka čepele prvního listu. Srovnáním různych variant a jamí odrůdy se ukázalo, že zkrácení délky čepele prvního listu nemá přímý vztah k jarovizaci.

The author carried out a cytological evaluation of 40 varieties of the basic Czechoslovak assortment of pears. Thirty of these were diploid and ten were diploid.
In addition to the chromosome number of these varieties, he determined the average dimension of the leaf stomata, to prove that it is possible to use this method in pear trees to make a reliable differentiation between diploid and triploid varieties. From a determination of the average lengths of the stomata it follows that the diploid varieties of pears can be distinguished from the triploid varieties by means of this criterion.
A further, very accurate mark of difference between diploid and triploid varieties, is the lagging of chromosomes in the spindle during the anaphase of the heterotypical division.
In the various varieties a divergent susceptibility to staining of the tissues was found which is not dependent on the method of microtechnical processing but in the first place, on the properties of each individual variety.
Regarding the statements of Darlington and Moffet on the one hand and Sax's objections on the other, the author's cytological findings in the case of triploid varieties are in agreement with those of Sax and also with his opinion on the debatableness of polyvalent associations found by Darlington and Moffet.

1. Le cicadineCalligypona pellucida FABR. est très vraisemblablement le vecteur des souches européennes de la jaunisse à virus des asters, les transmettant sur le poireau et l'oignon; cette maladie se manifeste surtout par la prolifération de 1'inflorescence.
2. Cette maladie n'était pas transmise par greffage des secteurs du bulbe du poireau atteint sur les bulbes de poireaux sains. On en peut donc conclure que le virus n'est pas présent dans le bulbe, ou qu'il n'y est qu'en quantité très petite, ou encore qu'il ne peut persister en état actif.
3. Le rapport entre les poireaux proliférés et les fleurs en l'inflorescence des plantes malades est variable, et il prouve ainsi la variabilité du niveau des virus dans l'inflorescence même.
4. Chez les plantes malades il n'y a que peu de graines qui se développent, et leur capacité de germination est faible.
5. Les expériences citées prouvent de nouveau tant l'acropétalité que la variabilité du niveau des virus dans les parties individuelles des plantes.

The foliar absorption and subsequent distribution of sodium, chlorine, calcium and zinc in one-year-old rooted cuttings ofForsythia intermedia ZABEL, and root absorption of phosphorus byTaxus cuspidata SIEB. and Zucc, was established. The percentage of the applied nutrient translocated out of the treated leaf was used as a criterion of mobility. Sodium and chlorine were found to be mobile, calcium immobile, and zinc slightly mobile. Less than one percent of the phosphorus applied to the shoots of both actively growing and semi-dormantTaxus cuspidata plants was recovered in the roots after a 12-day absorption-transport period. Six percent of the total phosphorus recovered in the tops was derived from a single soil application of a water soluble fertilizer (10-52-17) after 12 days, although, less than. 0.5 percent of the applied fertilizer phosphorus was absorbed.

The intensity of respiration and of photosynthesis were investigated simultaneously in sugar-beet leaves not detached from the plant. Several hours before the experiment the leaves had assimilated radioactive¹⁴CO2 whereafter they were placed into a normal leaf chamber for continuous gasometric estimation of the intensity of photosynthesis, according to the changes in the concentration of carbon dioxide in the passing air. At the same time, the specific activity of C0₂ was measured in the air that had passed through the assimilation chamber. From the values of the specific activity of CO₂ produced by the leaf in the dark the intensity of respiration in mg. CO₂ can be calculated.
It was found that sugar-beet leaves produce radioactive carbon dioxide when illuminated, both on the first and the second day after assimilation of labelled CO₂. During the considerable over-heating of leaves in the chamber when the gasometric method did not reveal anything but respiration a high production of¹⁴CO₂ could be observed radiometrically, corresponding to a higher respiration intensity. The authors explain this fact by the assumption that photosynthetic assimilation of carbon dioxide takes place simultaneously with respiration but the passive CO₂ balance in the gas exchange results in increased respiration, which actually represents the difference between the intensity of full photosynthesis and that of full respiration.
The production of carbon dioxide by whole sugar-beet leaves under illumination is no exceptional phenomenon under normal nutritional conditions.

In addition to the oat sterile-dwarf virus (OSDV) as the main agent causing grave damage to cereal crops in the Bohemian-Moravian Highlands during 1954-56, when the disease reached catastrophic proportions, it was found that wheat striate virus (WSV) also played a part. Symptomatological study showed that there are characteristic differences between the effect of WSV on the host plants and that of OSDV. Similarly to OSDV, however, WSV is specifically spread by the leafhopperCalligypona pellucida Fabr. Following long-term individual testing of vectors taken from localities infested with OSDV and WSV, four groups of insects were distinguished according to their pathogenic effects on cereal crops: 1. nonpathogenic, 2. producing OSDV symptoms, 3. producing WSV symptoms, 4. producing for the most part OSDV symptoms, but occasionally WSV or symptoms characteristic for both viruses simultaneously. WSV is persistent in its vector and is transferred byC. pellucida larvae at different stages of development and by imagos of both sexes. WSV tends to be transferred less regularly than OSDV. Considerable differences in efficiency of carrying WSV are to be found between individual leafhoppers, so that it is possible to assume the existence of races with varying efficiency in this respect. Among field populations in this country less efficient races prevail. For the transmission of WSV to be effected it was necessary for the vector to remain on the host for at least nine hours, but it seems that a shorter period might suffice. Extracts of crushed leaves of wheat plants suffering from the striate disease and from infective leafhoppers failed to cause infection when inoculated mechanically (by rubbing, injection) into plants. Attempts to achieve transmission through the soil or by dodder (Cuscuta campestris Yunck.) gave negative results. It was not possible to determine the thermal inactivation point of the virus in the live vector. The mosaic (zakuklivanie) virus of oat and the Russian mosaic of winter wheat as described in the U.S.S.R. differ from OSDV and WSV among other points by the production of typical inclusions and by the fact that they can easily be induced to crystallize.

Practical directions and examples are given for the use of quantitative ring precipitation to determine the intensity of cross reactions. The ability of this method to reproduce objectively the intensity of an antigen-antibody reacting system under various concentrations was verified. A comparison was made between Boyden's method of "complete curves" and the quantitative ring precipitation method.
The advantage of using quantitative ring precipitation is the saving of antiserum (0.05 ml. is sufficient for one determination), the smaller demand on working time and a noticeably reduced sensitivity to non-specific factors.
Quantitative ring precipitation (QRP) is a suitable method for quantitative experiments in immunochemistry and for purposes of comparative serology.

The growth of pollen tubes evokes changes in the level of free amino-acids in the style. This has been demonstrated in the cases of alanine, valine, leucine-isoleucine, serine, threonine, γ-aminobutyric acid, asparagine, glutamic acid and proline. These changes take place mainly in the parts of the style where the pollen tubes are present.
The most marked changes are an increase in the level of γ-aminobutyric acid and alanine and a decrease in glutamic acid. The intensity of these processes is much greater following compatible pollination than in the case of incompatible autogamy. On the assumption that the main course of γ-aminobutyric acid and alanine katabolism takes place by transamination with α-ketoglutaric acid, the basic nature of the above changes is explained as being due to a relative deficiency of the latter acid.
Alongside a reduction in the level of sugars an accumulation of asparagine takes place in pollinated styles. The rise in its level is considerably more rapid in cross-pollinated than in self-pollinated styles. If accumulation of asparagine is a result of more intensive consumption of proteins during respiration when there is a scarcity of sugars, it follows from the above results as from previous work (TUPý 1961), that pollen tubes use substrates from the style tissues for respiration and that this process is limited in the case of incompatible inhibition.
At the time when the pollen tubes are growing through the styles, the levels of γ-aminobutyric acid and alanine are already rising in the ovaries of pollinated flowers. This increase is quantitatively in direct ratio to the rate of pollen tube growth, which depends on the compatible or incompatible character of the pollination.

1. Photoperiodic experiments with the effect of short day during vernalization of winter wheat under field conditions have shown that the short day enhances development if applied during vernalization. Short day applied after vernalization prolonged the development.
2. At low intensity artificial illumination and under optimal vernalization temperatures vernalization proceeds the faster the longer the illumination. On increasing illumination intensity differences between the effect of short and long day are obliterated. Vernalization in the dark takes place only if saccharides are added.
3. It is assumed that even in green plants the accumulation of a certain amount of ergastic material, particularly saccharides, represents one of the conditions of vernalization. This accumulation may be achieved by longer illumination (under conditions of vernalization temperature and low illumination intensity), i.e. by a direct photosynthetic effect, or else by short day (under field conditions) causing a specific, photoperiodically controlled growth reaction which inhibits growth. When vernalization proceeds in the dark saccharides must be supplied.