In the second half of the 19th century there was in the Czech lands a stepwise transition from the smoke kiln to air kiln, so called. English design. During the 70s and 80s of the 19th century ...throughout the world phenomenally expanded semicontinuous mechanical kiln, an invention of the Czech brothers Jan and Josef Ječmen. The article describes the advantages and disadvantages of this system as well as the destiny of the above mentioned Czech inventors.
This paper reports the effects of selenium (Se) application on some physiological characteristics of barley (Hordeum vulgare L. cv. Rihane-03) exposed to drought stress. Foliar application to barley ...at 30 g selenium ha
, as sodium selenate, increased significantly shoot dry weight and relative water content in well-watered plants. A remarkable reduction in dry weight of water-stressed plants was associated with significant decrease in maximal efficiency of PSII (F
/F
), stomatal conductance (g
) and net CO
assimilation rate (A). Activity of antioxidant enzymes was increased by drought stress significantly. Amounts of malondialdehyde (MDA) and hydrogen peroxide (H
) remained unchanged in Sesupplemented water-deficit plants obviously because of an efficient scavenging following significant enhancement of catalase (CAT) and glutathione peroxidase (GSH-Px) activities. These results indicate that an application of selenium was favorable for biomass accumulation of barley plants under well-watered conditions. However, it did not significantly affect dry matter accumulation under drought stress, but Se-supplemented water-deficit plants exhibited better protection from oxidative damage because of higher CAT and GSH-Px activities and lower level of lipid peroxidation. These results suggest that selenium application can improve antioxidant defense system under drought stress conditions, and it may be recommended for arid and semiarid regions.
Članek poroča o učinku škropljenja s selenom na nekatere fiziološke značilnosti ječmena (Hordeum vulgare ‘Rihane- 03’), ki je bil izpostavljen sušnemu stresu. Foliarna aplikacija selena 30 g Se ha
, kot selenat je značilno povečala suho težo poganjkov in relativno vsebnost vode dobro zalivanih rastlin. Znatno zmanjšanje suhe teže rastlin v pomanjkanju vode je bilo povezano z značilnim zmanjšanjem maksimalne učinkovitosti PSII (Fv/Fm), stomatarne prevodnosti (g
) in neto asimilacije CO
(A). Aktivnost antioksidativnih encimov se je v sušnem stresu značilno povečala. Količini malondialdehida (MDA) in vodikovega peroksida (H
) sta ostali nespremenjeni pri rastlinah tretiranih s Se pri sušnem stresu, kar je bila očitno posledica delovanja Se, ki se je kazala kot povečana aktivnost katalaze (CAT) in glutation peroksidaze (GSH-Px). Ti izsledki kažejo, da uporaba Se prispeva k povečanju biomase ječmena pri dobri preskrbi z vodo. Vsebnost suhe snovi se pri rastlinah tretiranih s Se ni bistveno povečala v razmerah sušnega stresa, vendar pa so se te rastline bolje zaščitile pred oksidativnimi poškodbami s povečano aktivnostjo CAT in GSH-Px in manjšo peroksidacijo lipidov. Rezultati kažejo, da uporaba Se izboljša antioksidativno obrambo rastlin pri sušnem stresu in bi njegovo uporabo v te namene priporočali v aridnih in semiaridnih območjih.
Weendsko analizo, vsebnost rudninskih snovi in aminokislinsko sestavo smo opravili na definiranih vzorcih žit in koruze, pridelanih v Sloveniji leta 1997. Analizirali smo pet sort pšenice: pinka, ...ana, marija, rezka in žitarka; dve sorti ozimnega: alpha in robur ter dve sorti jarega ječmena: rex in gotic; tri sorte ovsa: valiant, pram in leanda in pet hibridov koruze: fanion, dea, helga, alberta in lotus. Pri pšenici in ječmenu smo ugotovili majhne razlike med posameznimi sortami v kemični sestavi. Pri ovsu izstopa sorta valiant po manjši vsebnosti surovih beljakovin in surovih maščob ter večji vsebnosti surove vlaknine. Pri koruzi pa odstopa hibrid fanion po večji vsebnosti surovih beljakovin in surovih maščob. Povprečne vrednosti posameznih hranljivih snovi v žitih, pridelanih v Sloveniji, se razlikujejo od literaturnih podatkov. Največja razlika je manjša vsebnost surovih beljakovin. V vsebnosti posameznih rudninskih snovi (P, Ca, Mg, K, Na, Zn in Mn) med sortami istega žita ni opaziti velikih razlik in povprečne vrednosti se dokaj dobro ujemajo z literaturnimi podatki, razen precej manjše vsebnosti natrija. Aminokislinska sestava beljakovin posameznih sort istega žita oz. koruze je podobna. V primerjavi z literaturnimi podatki smo ugotovili nekoliko večje koncentracije nekaterih esencialnih aminokislin v beljakovinah žit.
L. Begović, V. Galić, I. Abičić, Z. Lončarić, A. Lalić, and S. Mlinarić.
Obsahuje bibliografické odkazy
This study aimed to explore how ten selected winter barley genotypes responded to variations in ...environmental conditions during the growth season by using fast chlorophyll a fluorescence and normalized difference vegetation index (NDVI) at the booting, anthesis and early grain-filling stage. Lower amount of rainfall during the anthesis induced instability in the function of PSII, observed as the positive K-band in six and the positive L-band in seven genotypes. At grain filling, all genotypes displayed negative K- and L-bands, suggesting an increase of stability within PSII. The performance index increased from booting to grain filling in most genotypes. Chlorophyll a fluorescence parameters were incorporated into the partial least squares model as explanatory variables of NDVI. After a cross-validation, the model with four latent variables was chosen explaining 75.8% variance (r = 0.870) for NDVI. The principal component analyses showed two distinct types of the reaction of the barley genotypes to the mild drought stress at anthesis.
E. A. Lysenko.
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The rapid light curve method is a time-saving approach to the measurement of photosynthetic processes over a wide spectrum of light intensities. The ...adaptation to darkness enables the calculation of a complete set of coefficients for chlorophyll (Chl) fluorescence and P700 light absorption; however, dark-adapted plants demonstrate drastically different patterns of Chl fluorescence than that of light-adapted plants. The present work compared light-adapted barley plants without dark adaptation (L), and barley plants adapted to darkness and readapted to light for 7.5 min (D/L). The rapid light curves were generally similar in both the L and D/L variants. Some differences between the L and D/L variants were found in plants grown at any illumination. A number of distinctions between the L and D/L variants were characteristic of plants grown under particular illumination levels. The present analysis demonstrated that the scheme including dark adaptation and short readaptation to light (D/L) enabled to obtain generally correct data.
T. Istanbuli, M. Baum, H. Touchan, and A. Hamwieh.
Obsahuje bibliografické odkazy
Drought stress is one of the major constraints limiting the production and productivity of barley. We tried to ...identify some indicators related to plant productivity by analyzing some agro-morphological and physiological traits in recombinant inbred lines (RILs). Plants were exposed to three water treatments: well-watered at 70% available water content (AWC), mild drought stress at 35% AWC, and severe drought stress at 10% AWC. Our results revealed that drought significantly affected most of the studied morpho-physiological traits resulting in strong decreases in yield and the studied traits. We did not observe a significant difference in water-use efficiency between severe and mild drought conditions. Therefore, the mild stress treatment was considered as the most suitable water level in our study. Genotypes with the most tillers and spikes, the highest 1,000-grain mass, and biological yields achieved higher grain yields under all water stress conditions. Therefore, these traits could be considered as useful tools in breeding programs.
F. Bahrami, A. Arzani and M. Rahimmalek.
Obsahuje bibliografické odkazy
Terminal heat stress is one of the major constraints of cereal production. A two-year field investigation was performed to ...assess the response of Hordeum vulgare ssp. spontaneum genotypes to terminal heat stress using gas-exchange parameters, photosystem efficiency, proline accumulation, cell membrane leakage, and grain yield traits. Results of analysis of variance revealed the significant effects of heat stress (E), genotype (G), and G × E on the studied traits. The results of linear regression analysis showed that yield loss was inversely correlated with the maximum quantum yield of PSII photochemistry (Fv/Fm) and chlorophyll content. Path-coefficient analysis revealed that high Chl contents were either directly related to the grain yield or indirectly through the higher net photosynthetic rate and higher Fv/Fm values under high temperatures at the reproductive growth stage. Overall, the adapted wild genotypes exhibited physiological mechanisms capable of sustainable maintaining their yield capacity and plasticity flow, which could be exploited by crossing with cultivated barley to introgress heat tolerance.
Sestavili Vladimír Čihák, Bohdan Erben, Adolf Ernest, dr. Karel Holý, dr. Jan Jelínek, dr. Jos. Munzar, Karel Procházka, dr. Julius Stoklasa a Eugen Vítek
Josef Slabý
Zvl. otisk úvod. článku výstav. katalogu Ústř. společnosti hospod. pro král. české v Praze r. 1902
Josef Slabý
Zvl. otisk úvod. článku výstav. katalogu Ústř. společnosti hospod. pro král. ...české v Praze r. 1902
Josef Slabý
Zvl. the imprint of the introduction. an article of exhibitions. the Ústí catalog. companies of pubs. for the king. Czech in Prague 1902
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