In this study proteome changes in the stem of common bean (Phaseolus vulgaris L., cv. Tiber) under drought stress has been analysed. Proteins with changed abundance under drought have been identified with quantitative proteomic analysis and were grouped into several functional groups, mainly into energy metabolism, photosynthesis, proteolysis, protein synthesis and proteins related to defence and stress. The results of the study will contribute to understanding of mechanisms underlying drought stress tolerance in common bean and lead to identification of potential markers whose changes in abundance can be associated with quantitative characteristics used for description of stress tolerance on the genotype level.
COBISS.SI-ID: 5142376
The genus Wallemia comprises air- and food-borne, mycotoxigenic contaminants including the halophilic W. ichthyophaga, xerotolerant W. sebi and xerophilic W. muriae. Wallemia colonies are easily overlooked and only a comparably small number of strains have been deposited in culture collections so far. Therefore, more than 300 low-water-activity (aw) substrates and 30 air samples from a wide geographical coverage was tested, resulting in more than 150 new Wallemia isolates. Each species shows specialization to a specific low aw habitat. Different species of Wallemia are often present in agricultural environments, causing farmer’s lung disease. In this study new halotolerant species, W. hederae was described. Strains were tested for growth on different salts. The production of extracellular enzymes was confirmed in saline media, which supports their active occupation of low water activity environments.
COBISS.SI-ID: 3436111
Genetic diversity of 119 accessions of common bean (Phaseolus vulgaris) from five former Yugoslav republics constituting the western Balkans was assessed by 13 microsatellite markers. In the study, 118 alleles were detected or 9.1 per locus on average. Four groups (i.e., Slovene, Croatian, Bosnian, and Serbian) showed similarly high levels of genetic diversity as estimated by the number of different alleles, number of effective alleles, Shannon's information index, and expected heterozygosity. Mildly narrower genetic diversity was identified within a group of Macedonian accessions; however, this germplasm yielded the highest number of private alleles. All five germplasms share a great portion of genetic diversity as indicated by the analysis of molecular variance (AMOVA). We concluded that the most intensive gene flow in the region exists in Bosnia and Herzegovina. Cluster analysis based on collected molecular data classified the accessions into two large clusters that corresponded to two gene pools of origin (i.e., Andean and Mesoamerican). We found that Andean genotypes are more prevalent than Mesoamerican in all studied countries, except Macedonia, where the two gene pools are represented evenly. This could indicate that common bean was introduced into the western Balkans mainly from the Mediterranean Basin. Bayesian cluster analysis revealed that in the area studied an additional variation exists which is related to the Andean gene pool.
COBISS.SI-ID: 4823400
Our research in the last decade has been oriented towards obtaining a deeper insight into the molecular and morpho-physiological adaptation of common bean plants to drought. Differential gene expression study was conducted on leaves of eight common bean genotypes at different levels of dehydration. The results revealed the alteration of 15 drought-responsive transcripts. The expression profiles of selected genes were studied also in different bean species. The mode of expression was found consistent within Phaseolus spp. A proteomic approach was used to identify drought-responsive proteins in leaves of two cultivars differing in the response to drought, Tiber and more sensitive Starozagorski čern. The identified proteins were divided into different functional categories that include metabolic proteins, cellular defence/stress proteins, proteins involved in reactions of photosynthesis and proteins with unknown function. Analysis of stem proteome of cultivar Tiber under drought stress using in-gel stable isotope labelling revealed proteins grouped into several functional groups. By studying proteases we have shown that there are several serine endopeptidases and aminopeptidases in leaves of common bean which are differently affected by drought. A protease from leaves of cultivar Zorin has been studied in details; characterization at the protein and gene level led to its classification as a new plant subtilisinlike serine protease, named PvSLP2. The population of 80 recombinant inbred lines of the F8 generation derived by the cross between cultivars Tiber and Starozagorski čern was used for development of genetic map.
COBISS.SI-ID: 3924072
Common bean (Phaseolus vulgaris L.) was introduced in Europe from both Mesoamerican and Andean centers of origin and has been cultivated in central Europe for centuries. Great allelic polymorphism was detected in all four groups of examined accessions, indicating that Slovene and Austrian bean germplasm in the past possessed significant variation that has been well preserved till today. In factorial correspondence analysis accessions from different groups clustered together indicating potential gene flow between countries. The uncovered diversity corresponded very well to the two recognized gene pools (Andean and Mesoamerican). The majority of accessions in every single group belonged to Andean gene pool. Strong predominance of Andean genotypes classifies Slovenia among other Mediterranean countries, like Spain and Italy. The latter appears as a most probable source of first beans in Slovenia and Austria. We assume that in the beginning of the previous century after very tight relationships between Slovenia and Austria loosened, introgression of genotypes from western and northern European countries took place in Austria which resulted in very high proportion of Mesoamerican genotypes we found in present Austrian germplasm (44%). Several putative hybrids between the Andean and Mesoamerican gene pools were detected in this study.
COBISS.SI-ID: 4208744
Protein breakdown by proteases is basic to the plant response to abiotic stresses such as drought. A large number of genes encoding proteases or putative proteases exist in plants. Only a few of those involved in the response to drought have been characterized, and their regulation is poorly understood. We have identified two new subtilases from leaves of Phaseolus vulgaris L. cultivar Zorin, PvSLP1 and PvSLP2. PvSLP1 was identified at the gene level, using primers based on the gene sequence of the putative drought induced serine protease from Arachis hypogaea L. In P. vulgaris, expression of the PvSLP1 transcript did not change on water withdrawal. PvSLP2 was isolated and characterized at the protein level, together with complete gene and cDNA sequences. The deduced amino acid sequences of both PvSLP1 and PvSLP2 are characteristic of plant subtilases of the S8 family of clan SB. PvSLP2 shows 33% sequence identity to PvSLP1. Expression of the PvSLP2 transcript did not change on withdrawal of water, but its proteolytic activity in leaves increased, depending on the age and position of the leaf. In addition, the level of activity in senescent leaves of well watered plants was higher than in mature or young leaves. These results, together with the fact that PvSLP2 cleaves peptide bonds following an Arg residue, point to regulation of PvSLP2 subtilase activity at translational and/or post-translational levels and suggest a specific role in the response to drought and senescence.
COBISS.SI-ID: 26305831
The aim of this work was to determine the influence of different storage temperatures and tuber maturity on development of tuber necrosis caused by Potato virus Y NTN . Infected tubers of the cultivar Igor of two different maturity groups and noninfected tubers were randomly distributed into 12 storage regimes. Control treatments were stored at constant temperatures of 4, 13 and 24°C. Tubers in the other nine treatments were stored at 4°C at the beginning of experiment and transferred to 24°C after 1 to 29 weeks after harvest. High storage temperatures enhanced the development of tuber necrosis. Prolongation of low temperature storage delayed the development of necrosis and reduced the number of tubers with necrosis. When tubers were stored at low temperature for 21 weeks or more, no necrosis developed after transfer to high temperature. We could not confirm the effect of maturity on development of necrosis caused by PVYNTN.
COBISS.SI-ID: 3597928
According to International Code of Nomenclature for algae, fungi, and plants, new rules apply since 1st January 2013 for the naming of pleomorphic fungi. As a result of an analysis, the generic naming of important plant pathogenic fungi and biological control agents was discussed and the use of Clonostachys over Bionectria, Trichoderma over Hypocrea, Fusarium over Gibberella, and Neonectria over Cylindrocarpon (etc.) recommended.
COBISS.SI-ID: 4289896
An unidentifyable SBFS fungus was retrieved as an epiphyte from ripening apples. DNA sequence based phylogenetic analyses and its micromorphology on artifical media suggested that it is related to Peltaster fructicola described earlier from North America. The European species is newly described as Peltaster cerophilus and the type material of P. fructicola redescribed. Two group I introns were discovered in the nuclear small ribosomal RNA subunit gene sequences of P. cerophilus. The specific features of one of these introns are unique for the sofar analyzed strains of P. cerophilus and could be used for diagnostics and epidemiological purposes.
COBISS.SI-ID: 4463720
Like other pathogens, plant parasitic nematodes employ effector proteins to alter plant cellular functions and successfully infect their hosts. We have generated a library of ORFs encoding putative Globodera rostochiensis apoplastic effectors in vectors for expression in planta. These clones were assessed for morphological and developmental effects on plants as well as their ability to induce or suppress plant defenses. Predicted cell wallmodifying proteins induced necrosis and chlorosis, consistent with roles in cell fate alteration and tissue invasion, respectively. We showed a novel role for an apoplastic expansin-like protein (GrEXPB2) in suppressing intra-cellular defense responses. GrEXPB2 also elicited defense response in species- and sequence-specific manner.
COBISS.SI-ID: 4630888