We explored the potential of a fungal strain Aspergillus costaricensis KS1 for modulating growth and nutrient mobilization in rice. At laboratory conditions, there was a decline in pH of the medium on inoculation with the strain and the production of citric acid was observed under broth conditions. Similarly, there was higher solubilization of tricalcium phosphate and siderophore production in liquid medium on inoculation with the strain. The effect of inoculation of KS1 was studied in rice and higher growth and yield were observed on inoculation compared to control. The content of phosphorus and iron in stem and roots of KS1 inoculated plants was higher in comparison with uninoculated control. There was also increased availability of phosphorus and iron content in soil grown with KS1 inoculated plants. In addition, inoculation with strain resulted in a higher content of volatile organic compounds such as linoleic acid, linolenic acid, and ethyl isoallocholate in stem of rice. A. costaricensis KS1 can be used for improving phosphorus and iron nutrition and impart tolerance against stresses in rice.
- MeSH
- Aspergillus * metabolismus růst a vývoj MeSH
- fosfor * metabolismus analýza MeSH
- fosforečnany vápenaté metabolismus MeSH
- koncentrace vodíkových iontů MeSH
- kořeny rostlin mikrobiologie metabolismus MeSH
- kyselina citronová metabolismus MeSH
- půdní mikrobiologie MeSH
- rýže (rod) * mikrobiologie metabolismus růst a vývoj MeSH
- siderofory * metabolismus MeSH
- stonky rostlin mikrobiologie metabolismus chemie MeSH
- těkavé organické sloučeniny * metabolismus analýza MeSH
- železo * metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
The role of trees in the nitrous oxide (N2O) balance of boreal forests has been neglected despite evidence suggesting their substantial contribution. We measured seasonal changes in N2O fluxes from soil and stems of boreal trees in Finland, showing clear seasonality in stem N2O flux following tree physiological activity, particularly processes of CO2 uptake and release. Stem N2O emissions peak during the vegetation season, decrease rapidly in October, and remain low but significant to the annual totals during winter dormancy. Trees growing on dry soils even turn to consumption of N2O from the atmosphere during dormancy, thereby reducing their overall N2O emissions. At an annual scale, pine, spruce and birch are net N2O sources, with spruce being the strongest emitter. Boreal trees thus markedly contribute to the seasonal dynamics of ecosystem N2O exchange, and their species-specific contribution should be included into forest emission inventories.
- MeSH
- atmosféra chemie MeSH
- ekosystém * MeSH
- methan metabolismus MeSH
- oxid dusný metabolismus MeSH
- oxid uhličitý metabolismus MeSH
- půda chemie MeSH
- roční období * MeSH
- stonky rostlin metabolismus MeSH
- stromy fyziologie MeSH
- tajga * MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Finsko MeSH
WEE1 regulates the cell cycle by inactivating cyclin dependent protein kinases (CDKs) via phosphorylation. In yeast and animal cells, CDC25 phosphatase dephosphorylates the CDK releasing cells into mitosis, but in plants, its role is less clear. Expression of fission yeast CDC25 (Spcdc25) in tobacco results in small cell size, premature flowering and increased shoot morphogenetic capacity in culture. When Arath;WEE1 is over-expressed in Arabidopsis, root apical meristem cell size increases, and morphogenetic capacity of cultured hypocotyls is reduced. However expression of Arath;WEE1 in tobacco plants resulted in precocious flowering and increased shoot morphogenesis of stem explants, and in BY2 cultures cell size was reduced. This phenotype is similar to expression of Spcdc25 and is consistent with a dominant negative effect on WEE1 action. Consistent with this putative mechanism, WEE1 protein levels fell and CDKB levels rose prematurely, coinciding with early mitosis. The phenotype is not due to sense-mediated silencing of WEE1, as overall levels of WEE1 transcript were not reduced in BY2 lines expressing Arath;WEE1. However the pattern of native WEE1 transcript accumulation through the cell cycle was altered by Arath;WEE1 expression, suggesting feedback inhibition of native WEE1 transcription.
- MeSH
- geneticky modifikované rostliny MeSH
- kořeny rostlin genetika metabolismus MeSH
- kultivované buňky MeSH
- květy genetika metabolismus MeSH
- listy rostlin genetika metabolismus MeSH
- mitóza genetika MeSH
- protein-serin-threoninkinasy genetika metabolismus MeSH
- proteiny huseníčku genetika metabolismus MeSH
- regulace genové exprese u rostlin MeSH
- stonky rostlin genetika metabolismus MeSH
- tabák cytologie genetika metabolismus MeSH
- velikost buňky MeSH
- výhonky rostlin genetika metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
We studied thallium (Tl) isotope fractionation in white mustard grown hydroponically at different Tl doses. Thallium isotope signatures in plants indicated preferential incorporation of the light 203Tl isotope during Tl uptake from the nutrient solution. Negative isotope fractionation was even more pronounced in dependence on how much the available Tl pool decreased. This finding corresponds to the concept of isotope overprinting related to a high contamination level in the growing media (solution or soil). Regarding Tl translocation in plants, we observed a large Tl isotope shift with an enrichment in the heavy 205Tl isotope in the shoots relative to the roots in treatments with low/moderate solution Tl concentrations (0.01/0.05 mg Tl/L), with the corresponding α205/203Tl fractionation factors of ˜1.007 and 1.003, respectively. This finding is probably a consequence of specific (plant) reactions of Tl replacing K in its cycle. The formation of the S-coordinated Tl(I) complexes, potentially affecting both Tl accumulation and Tl isotope fractionation in plants, however, was not proven in our plants, since we did not have indication for that on the basis of X-ray absorption spectroscopy, suggesting that Tl was mainly present as free/hydrated Tl+ ion or chemically bound to O-containing functional groups.
- MeSH
- algoritmy MeSH
- biomasa MeSH
- Brassica metabolismus MeSH
- hořčice rodu Brassica metabolismus MeSH
- kořeny rostlin metabolismus MeSH
- kovy metabolismus MeSH
- listy rostlin metabolismus MeSH
- radioaktivní znečišťující látky MeSH
- radioizotopy thallia chemie metabolismus MeSH
- stonky rostlin metabolismus MeSH
- thallium chemie metabolismus MeSH
- výhonky rostlin metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
This study presents results from continuous measurements of stem CO2 efflux carried out for seven experimental seasons (from May to October) in a young Norway spruce forest. The objectives of the study were to determine variability in the response of stem CO2 efflux to stem temperature over the season and to observe differences in the calculated relationship between stem temperature and CO2 efflux based on full growing season data or on data divided into periods according to stem growth rate. Temperature sensitivity of stem CO2 efflux (Q10) calculated for the established periods ranged between 1.61 and 3.46 and varied over the season, with the lowest values occurring in July and August. Q10 calculated using data from the full growing seasons ranged between 2.30 and 2.94 and was often significantly higher than Q10 calculated for the individual periods. Temperature-normalized stem CO2 efflux (R10) determined using Q10 from growing season data was overestimated when the temperature was below 10 °C and underestimated when the temperature was above 10 °C, compared with R10 calculated using Q10 established for the individual periods. The differences in daily mean R10 calculated by these two approaches ranged between -0.9 and 0.2 μmol CO2 m-2 s-1. The results of this study confirm that long periods for determining the temperature dependence of stem CO2 efflux encompass different statuses of the wood (especially in relation to stem growth). This may cause bias in models using this relationship for estimating stem CO2 efflux as a function of temperature.
- MeSH
- biologické modely MeSH
- lesy MeSH
- meteorologické pojmy MeSH
- oxid uhličitý metabolismus MeSH
- roční období MeSH
- smrk fyziologie MeSH
- stonky rostlin růst a vývoj metabolismus MeSH
- stromy fyziologie MeSH
- teplota MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
A model small-scale field experiment was set up to investigate selenium (Se) uptake by four different varieties of broccoli plants, as well as the effect of Se foliar application on the uptake of essential elements for plants calcium (Ca), copper (Cu), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), phosphorus (P), sulfur (S), and zinc (Zn). Foliar application of sodium selenate (Na2SeO4) was carried out at two rates (25 and 50 g Se/ha), and an untreated control variant was included. Analyses of individual parts of broccoli were performed, whereby it was found that Se in the plant accumulates mainly in the flower heads and slightly less in the leaves, stems, and roots, regardless of the Se rate and broccoli variety. In most cases, there was a statistically significant increase of Se content in all parts of the plant, while there was no confirmed systematic influence of the addition of Se on the changing intake of other monitored elements. Selenization of broccoli leads to an effective increase in the Se content at a rate of 25 g/ha, whereas the higher rate did not result in a substantial increase of Se content compared to the lower rate in all varieties. Therefore, the rate of 25 g/ha can be recommended as effective to produce broccoli with an increased Se content suitable for consumption. Moreover, Se application resulted in an adequate increase of the main organic compounds of Se, such as selenocystine (SeCys2), selenomethionine (SeMet), and Se-methylselenocysteine (Se-MeSeCys).
- MeSH
- biologický transport MeSH
- Brassica účinky léků metabolismus MeSH
- cystin analogy a deriváty izolace a purifikace metabolismus MeSH
- kationty dvojmocné metabolismus MeSH
- kationty jednomocné metabolismus MeSH
- kořeny rostlin účinky léků metabolismus MeSH
- květy účinky léků metabolismus MeSH
- listy rostlin účinky léků metabolismus MeSH
- organoselenové sloučeniny izolace a purifikace metabolismus MeSH
- selenocystein analogy a deriváty izolace a purifikace metabolismus MeSH
- selenomethionin izolace a purifikace metabolismus MeSH
- sloučeniny selenu izolace a purifikace metabolismus farmakologie MeSH
- spektrofotometrie atomová MeSH
- stonky rostlin účinky léků metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Uptake of (14)C-labeled fluoranthene ([(14)C]FLT) via both roots and leaves of Pisum sativum seedlings and distribution of [(14) C] in plants by both acropetal and basipetal transport was evaluated. The highest [(14)C] level was found in the root base (≈270 × 10(4) dpm/g dry wt) and the lowest level in the stem apex (<2 × 10(4) dpm/g dry wt) after just 2 h of root exposure. For foliar uptake, the highest level of [(14)C] was found in the stem and root apex (both ≈2 × 10(4) dpm/g dry wt) (except for treated leaves), while the lowest level was found in the root base (<0.6 × 10(4) dpm/g dry wt).
- MeSH
- biologický transport MeSH
- fluoreny analýza metabolismus MeSH
- hrách setý metabolismus MeSH
- kořeny rostlin metabolismus MeSH
- látky znečišťující životní prostředí analýza metabolismus MeSH
- listy rostlin metabolismus MeSH
- monitorování životního prostředí MeSH
- radioizotopy uhlíku analýza metabolismus MeSH
- stonky rostlin metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The ability of thorium uptake as well as responses to heavy metal stress were tested in tobacco cultivar La Burley 21. Thorium was accumulated preferentially in the root system. The presence of citric, tartaric and oxalic acids in hydroponic medium increased thorium accumulation in all plant organs. On the other hand, the addition of diamines and polyamines, the important antioxidants in plants, resulted in decrease of thorium accumulation, especially in the root system. Negative correlation was found between putrescine concentration and thorium accumulation. Nevertheless, the most important factor influencing the accumulation of thorium was the absence of phosphate ions in a hydroponic medium that caused more than 10-fold increase of thorium uptake in all plant parts. Accumulation and distribution of thorium was followed in six cultivars and 14 selected transformants. Cultivar La Barley 21 represented an average between the tested genotypes, having a very good distribution ratio between roots, stems and leaves.
- MeSH
- diaminy chemie farmakologie MeSH
- fosfáty chemie nedostatek MeSH
- genotyp MeSH
- hydroponie MeSH
- ionty chemie MeSH
- kořeny rostlin účinky léků metabolismus MeSH
- listy rostlin účinky léků metabolismus MeSH
- polyaminy chemie farmakologie MeSH
- putrescin chemie farmakologie MeSH
- stonky rostlin účinky léků metabolismus MeSH
- tabák metabolismus MeSH
- thorium chemie metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Shoot branching is one of the major determinants of plant architecture. Polar auxin transport in stems is necessary for the control of bud outgrowth by a dominant apex. Here, we show that following decapitation in pea (Pisum sativum L.), the axillary buds establish directional auxin export by subcellular polarization of PIN auxin transporters. Apical auxin application on the decapitated stem prevents this PIN polarization and canalization of laterally applied auxin. These results support a model in which the apical and lateral auxin sources compete for primary channels of auxin transport in the stem to control the outgrowth of axillary buds.
- MeSH
- hrách setý genetika růst a vývoj metabolismus MeSH
- kyseliny indoloctové metabolismus MeSH
- regulace genové exprese u rostlin MeSH
- regulátory růstu rostlin metabolismus MeSH
- rostlinné proteiny genetika metabolismus MeSH
- stonky rostlin růst a vývoj metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Stems of amaranthus are considered as prospective biofuel in the Czech Republic. The study presents results of water sorption tests of this biomass in the range of 10-30 degrees C and water activity (a(w)) ranging from 0.4 to 0.99. The experimental procedure used was a gravimetric dynamic method. Four sorption models (Chung-Pfost, Halsey, Henderson, Oswin) were evaluated. The modified Henderson's equation was the best model for moisture adsorption and desorption of amaranthus stems. Critical values of equilibrium moisture content, corresponding to the a(w)=0.6, were 11.45% and 13.28%(wb) for water adsorption and desorption respectively, at the temperature of 20 degrees C. Heat of sorption (q(st)) was calculated using the chosen sorption model and Clausius-Clapeyron equation. An exponential function was found to fit the experimental q(st) values of amaranthus stems at moisture contents ranging from 7% to 40%(wb) for adsorption and desorption.
