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Abstract: Background Potato virus Y (PVY) is a major pathogen that causes substantial economic losses in worldwide potato production. Different potato cultivars differ in resistance to PVY, from severe susceptibility, through tolerance, to complete resistance. The aim of this study was to better define the mechanisms underlying tolerant responses of potato to infection by the particularly aggressive PVYNTN strain. We focused on the dynamics of the primary metabolism-related processes during PVYNTN infection. Results A comprehensive analysis of the dynamic changes in primary metabolism was performed, which included whole transcriptome analysis, nontargeted proteomics, and photosynthetic activity measurements in potato cv. Désirée and its transgenic counterpart depleted for accumulation of salicylic acid (NahG-Désirée). Faster multiplication of virus occurred in the NahG-Désirée, with these plants developing strong disease symptoms. We show that while the dynamics of responses at the transcriptional level are extensive and bimodal, this is only partially translated to the protein level, and to the final functional outcome. Photosynthesis-related genes are transiently induced before viral multiplication is detected and it is down-regulated later on. This is reflected as a deficiency of the photosynthetic apparatus at the onset of viral multiplication only. Interestingly, specific and constant up-regulation of some RuBisCO transcripts was detected in Désirée plants, which might be important, as these proteins have been shown to interact with viral proteins. In SA-deficient and more sensitive NahG-Désirée plants, consistent down-regulation of photosynthesis-related genes was detected. A constant reduction in the photochemical efficiency from the onset of viral multiplication was identified; in nontransgenic plants this decrease was only transient. The transient reduction in net photosynthetic rate occurred in both genotypes with the same timing, and coincided with changes in stomatal conductivity. Conclusions Down-regulation of photosynthesis-related gene expression and decreased photosynthetic activity is in line with other studies that have reported the effects of biotic stress on photosynthesis. Here, we additionally detected induction of light-reaction components in the early stages of PVYNTN infection of tolerant interaction. As some of these components have already been shown to interact with viral proteins, their overproduction might contribute to the absence of symptoms in cv. Désirée.
Keywords: plant-pathogen interactions, Potato virus Y, potyviridae, salicylic acid, whole transcriptome analysis, shot-gun proteomics, photosynthetic parameters
Published in DiRROS: 29.07.2024; Views: 120; Downloads: 147
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Abstract: In the period 1974-1989, 219 patients with supradiaphragmatic clinical stage I and II Hodgkin's disease were treated at the Institute of Oncology in Ljubljana; of these 95 (43%) patients underwent staging laparotomy. Of laparotomized patients, those with pathological stage III-IV, and of non-laparotomized, those with unfavorable prognostic factors (B-symptoms, bulky mediastinum) received chemotherapy: the remaining patients were treated by irradiation. No statistically significant difference in the survival and disease-free survival between laparotomized and nonlaparotomized patients could be found.
Published in DiRROS: 16.01.2024; Views: 368; Downloads: 82
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Published in DiRROS: 15.01.2024; Views: 404; Downloads: 97
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Keywords: Hodkinova bolezen
Published in DiRROS: 14.09.2023; Views: 544; Downloads: 122
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Abstract: Monografija obsega pregled znanja na področju prilagoditve oljk na sušne razmere ter pregled tehnologij namakanja oljk. Res je, da je oljka manj zahtevna vrsta, saj lahko uspeva v izjemno skeletnih tleh in je zelo dobro prilagojena na pomanjkanje vode v njih, a kljub fiziološkim prilagoditvam, lahko sušne razmere negativno vplivajo na rast, razvoj in pridelek oljk. Sušni stres lahko pri oljkah blažimo z deficitnim namakanjem. Deficitni način namakanja je oblika nadgradnje namakanja, saj z nadzorovanim primanjkljajem vode zagotovimo kakovost pridelka, obstoj rastline ter hkrati zmanjšamo porabo vode in energije. Deficitni način namakanja, temelji na načelu, da obrok vode dodamo takrat, ko ga rastlina najbolj gospodarno uporabi. Pri tem je ključnega pomena poznavanje rastlinske vrste, njenih anatomskih in morfoloških značilnosti, fizioloških prilagoditev na sušo, biokemijski odziv na stresne dejavnike in s tem vpliv na kakovost plodov in olja. Poleg tega je potrebno tudi poznavanje dejavnikov, ki vplivajo na pridelovalne sposobnosti oljk, kot so lastnosti tal s svojimi vodno zadrževalnimi sposobnostmi ter dostopna voda v tleh. Ob skrbnem upoštevanju potreb rastline in okoljskih razmer z ustreznim delovanjem namakalnega sistema lahko dosežemo usklajeno razmerje med kakovostjo in količino pridelka o hkratnem varovanju potencialov naravnih virov.
Published in DiRROS: 14.06.2022; Views: 974; Downloads: 581
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