We studied how tomato (Lycopersicon esculentum Mill.) chloroplast omega-3 fatty acid desaturase gene (Lefad7) overexpression enhanced low-temperature (LT) tolerance in transgenic tomato plants. In these plants, the content of linolenic acid (18:3) markedly increased and, correspondingly, the content of linoleic acid (18:2) decreased. Similar changes were found after 6 h under LT (4°C) treatment. Under LT stress, wild type (WT) tomato plants showed a much greater increase in relative electrolyte leakage and malondialdehyde (MDA) contents compared with transgenic plants. Transgenic plants exhibited higher activities of antioxidative enzymes and a lower content of reactive oxygen species (ROS). Transgenic plants maintained a relatively higher level of the net photosynthetic rate (PN) and chlorophyll (Chl) content than WT plants under LT stress. Taken together, we suggested that overexpression of Lefad7 enhanced LT tolerance by changing the composition of membrane lipids in tomato plants, with the increased content of trienoic fatty acids and reduced content of dienoic fatty acids that led to series of physiological alterations., X. Y. Liu ... [et al.]., and Obsahuje bibliografii
Článek přináší poznatky o vznikajících mezidruhových vztazích v ekosystémech po zavlečení nového invazního druhu rostliny – netýkavky žláznaté (Impatiens glandulifera) – a uvádí některé entomologické aspekty jejího masového výskytu v novém prostředí., The impact of aphids on the invasive plant Impatiens glandulifera in the Czech Republic is shown and some entomological aspects of I. glandulifera distribution in local ecosystems are discussed., and Petr Starý, Jan Havelka.
Entomopathogenic nematodes from families Steinernematidae and Heterorhabdi - tidae and the molluscoparasitic nematode Phasmarhabditis hermaphrodita are enigmatic soil creatures. These lethal pathogens of invertebrates can also be used as effective and safe biocontrol agents. In this article, we review the biology, ecology and distribution of these organisms and we de - pict their current use in biological control. and Jiří Nermuť, Vladimír Půža, Zdeněk Mráček.
Ernst Schäfer (1910-1992) byl německý zoolog, sběratel přírodnin a cestovatel známý zejména díky třem průkopnickým výpravám do Tibetu, území, kam se přírodovědci prakticky nedostali až do druhé poloviny 20. století. Třetí expedice z let 1938-39 je poněkud kontroverzní, neboť se stala součástí nacistické propagandy a její cíle nebyly čistě jen vědecké., Ernst Schäfer (1910–92) was a German zoologist, collector and explorer who is primarily known for his three pioneering expeditions to Tibet, which was virtually closed to science well into the second half of the 20th century. The third expedition, in 1938–39, was rather controversial as it became a part of Nazi propaganda and its goals were not purely scientific., and Jan Robovský, Jiří Hrubý.