The present research was conducted to assess physiological responses of ‘Malas-e-Saveh’ (Malas) and ‘Shishe-Kab’ (Shishe) pomegranates to water of different salt content and electrical conductivity (1.05, 4.61, and 7.46 dS m-1). Both cultivars showed a reduced trunk length due to salinity. Relative water content and stomatal conductivity of both cultivars were significantly reduced under salt stress, but ion leakage increased. In both cultivars, total chlorophyll (Chl) and carbohydrates decreased with rise in salinity, while proline accumulation increased. With salinity increment, the Chl fluorescence parameters (maximum photochemical efficiency of PSII and effective quantum yield of PSII) declined significantly in both cultivars, with higher reduction observed in Shishe. Generally, more Na+ accumulated in shoots and more Cl- was observed in leaves. Cl- accumulation increased by salinity in leaves of Malas, but it was reduced in Shishe. The K+/Na+ ratio in leaves decreased in both cultivars by salinity increment. Malas was less affected by osmotic effects of NaCl, but it accumulated more Cl- in its leaves. Thus, Malas might be more affected by negative effects of salinity., M. Khayyat, A. Tehranifar, G. H. Davarynejad, M. H. Sayyari-Zahan., and Obsahuje bibliografii
Parazitické stádium velkých mlžů (řád Unionida) vytváří velmi těsné spojení mezi těmito druhy a jejich rybími hostiteli. Tento článek představuje variabilitu mezidruhových interakcí na příkladech středoevropských druhů., The parasitic stage of freshwater mussels (order Unionida) constitutes a tight host-affiliate linkage between mussels and their host fish. This article presents the variability of interactions using the Central European species as a model group., and Karel Douda.
Velemyši, dříve nazývané krysy obláčkové, jsou největší myšovití hlodavci žijící endemicky na Filipínách. Velemyš dinagatskou (Crateromys australis), považovanou za potenciálně vyhynulou, se nám podařilo znovuobjevit 37 let od jejího posledního (a zároveň prvního) nálezu a vědeckého popisu. To bylo také impulzem k návrhu nového českého jména velemyši pro celou skupinu obláčkových krys. Velemyš dinagatská byla nalezena na severu ostrova Dinagat. Nyní je řazena mezi kriticky ohrožené druhy. Ohrožené jsou také ostatní druhy této skupiny, a to zejména kvůli masivní těžbě dřeva a nerostných surovin a tím ničením jejich přirozeného prostředí. Proto je cílená ochrana je nezbytná k přežití tohoto i ostatních druhů velemyší., Cloud rats are the largest murid rodents endemic to the Philippines. The Dinagat Cloud Rat (Crateromys australis), considered to be potentially extinct, was rediscovered in the north of Dinagat Island after 37 years from its first discovery and scientific description. We have also proposed a new Czech name. The species is now listed as critically endangered. All cloud rats are threatened by the destruction of their natural habitats by logging and mining. Targeted protection is therefore essential for their survival., and Milada Řeháková, Václav Řehák.
Rychlý růst počtu nepůvodních druhů je jednou z nejzávažnějších hrozeb pro světovou biodiverzitu i pro zemědělství. V článku jsou představeny dva druhy kněžic, jejichž rozšíření do České republiky v nejbližších letech očekáváme: invazní kněžice mramorovaná (Halyomorpha halys) pochází z východní Asie, kosmopolitní kněžice zeleninová (Nezara viridula) se šíří ze Středomoří patrně přirozeně v závislosti na globálním oteplování. Jelikož oba druhy jsou významnými zemědělskými škůdci, jsou uvedeny základní znaky sloužící k jejich rozlišení a rovněž údaje o jejich biologii a škodlivosti., A rapid increase in the number of alien species is one of the most important threats to global biodiversity as well as to agriculture. The article presents two species of the family Pentatomidae which are expected to reach the Czech Republic in the near future - the invasive Brown Marmorated Stink Bug (Halyomorpha halys) native to East Asia, and the cosmopolitan Southern Green Stink Bug (Nezara viridula), probably spreading naturally northwards from the Mediterranean due to global warming. Because both species are serious pests in agriculture, the key characteristics facilitating their identification are provided and illustrated along with information on their bionomics and pest status., and Petr Kment.
Tomato samples were collected from the field of Absheron peninsula in Azerbaijan in order to evaluate the incidence of main Tobamoviruses. According to results of serological and molecular tests, Tomato mosaic virus (ToMV), Tobacco mosaic virus (TMV), and Pepper mild mottle virus (PMMoV) were detected as single and mixed infections (TMV + PMMoV; ToMV + PMMoV) in various tomato samples. It was found that Tobamovirus infection caused an increase in the content of malondialdehyde, alterations in the activities of peroxidase enzymes and quantitative and qualitative changes in their molecular isoforms. A comparison of thylakoid membrane polypeptides from virus-infected leaves indicated a decrease in the content of the thylakoid membrane polypeptides with molecular masses of 123, 55, 47, 33, 28-24, 17, and 15 kD. PSII efficiency and the content of chlorophylls (a and b) were significantly lower in the virus-infected leaves., I. M. Huseynova, S. M. Mirzayeva, N. F. Sultanova, D. R. Aliyeva, N. Sh. Mustafayev, J. A. Aliyev., and Obsahuje bibliografii
Dependence of ATP hydrolysis kinetics by the chloroplast coupling factor (CF1) on medium viscosity was studied at varying temperatures. For samples with oxidized and reduced CF1 γ-subunit, this dependence was shown to be described by Cramers’ relationship k - (η/ηo)-n, where k is the reaction rate constant, η/ηo is the medium/water viscosity ratio, and 0 < n < 1. Transition of the γ-subunit from its reduced to oxidized state was accompanied by increasing n value, which is indicative of increasing friction losses between certain enzyme sections and the solution. The increased medium viscosity produced no effect on the reaction activation energy which appeared to be almost the same for the both enzyme states. The molecular mechanisms responsible for CF1 activity loss in viscous media are discussed., A.N. Malyan., and Obsahuje bibliografii
Druhé pokračování o významu vitaminu D pro zdraví člověka (první bylo publikováno v Živě 4/2015) se zabývá jeho úlohou, kterou hraje v imunitě. Donedávna se nepředpokládalo, že by vitamin D mohl podmiňovat také imunitní procesy. Během posledních let se však nashromáždil dostatečný počet experimentálních i klinických studií, které dokládají, že při jeho nedostatečném příjmu dochází k poklesu zejména antiinfekční imunity, a souběžně s tím stoupá také riziko vzniku nesdělných onemocnění. Účelem tohoto sdělení není vyčerpávající informace o mechanismech jeho působen na imunitní systém, ale upozornění pro specialisty i laiky na tuto důležitou, ale prozatím opomíjenou problematiku., This is a further continuation of an 8/2015 article about the importance of vitamin D to the health of human beings (the first was published in Živa 4/2015). The article deals with the role that the vitamin plays in immunity. Until recently, it was not assumed that vitamin D could also be conditional upon immune processes and that it determines the correct function of both natural and adaptive immunity. In recent years, however, a sufficient number of experimental and clinical studies have accumulated, providing evidence that insufficient intake of vitamin D could not only induce decreased immunity to infection but also contribute substantially to an increased risk of non-communicable diseases. The purpose of this communication is not exhaustive information on the mechanisms of vitamin D effects on the immune system, but as an alert to specialists and laymen on hitherto neglected issues., and Petr Šíma, Bohumil Turek.