The Arabidopsis thaliana L. photoreceptor genes homologues in tomato (Solanum lycopersicum L.) genome were analysed using bioinformatic tools. The expression pattern of these genes under cold stress was also evaluated. Transcriptome... more
The Arabidopsis thaliana L. photoreceptor genes homologues in tomato (Solanum lycopersicum L.) genome were analysed using bioinformatic tools. The expression pattern of these genes under cold stress was also evaluated. Transcriptome analysis of the tomato sequence revealed that the photoreceptor gene family is involved in abiotic stress tolerance. They participate in various pathways and controlling multiple metabolic processes. They are structurally related to PAS, LIGHT-OXYGEN-VOLTAGE-SENSING (LOV), DNA photolyase, 5,10-methenyl tetrahydrofolate (MTHF), flavin-binding kelch F-box, GAF, PHY, Seven-bladed β-propeller and C27 domains. They also interact with flavin adenine dinucleotide (FAD), (5S)-5-methyl-2-(methylsulfanyl)-5-phenyl-3-(phenylamino)-3,5-dihydro-4H-imidazol-4-one (FNM) and Phytochromobilin (PϕB) ligands. These interactions help to create a cascade of protein phosphorylation involving in cell defence transcription or stress-regulated genes. They localisation of these g...
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Progressing climate change necessitates the search for solutions of plant protection against the effects of water deficit. One of these solutions could be silicon supplementation. The aim of the study was to verify the hypothesis that... more
Progressing climate change necessitates the search for solutions of plant protection against the effects of water deficit. One of these solutions could be silicon supplementation. The aim of the study was to verify the hypothesis that silicon changes aquaporin expression and antioxidant system activity in a direction which may alleviate the effects of drought stress in oilseed rape. The accumulation of BnPIP1, BnPIP2-1-7 and BnTIP1;1 aquaporins and the expression of their genes, the level of catalase, superoxide dismutase activities and hydrogen peroxide content as well as total non-enzymatic antioxidant activity were analyzed in leaf tissue from control and silicon-treated oilseed rape plants growing under well-watered and drought conditions. Silicon was applied in two forms - pure silicon and a silicon complex. It was shown that under drought conditions, both pure silicon and the silicon complex (with Fe) significantly increased the accumulation of aquaporins and improved the activity of enzymatic and non-enzymatic components of the antioxidant system, while under well-watered conditions, these effects were observed only in the case of the silicon complex. The presented study proves that silicon supplementation in oilseed rape improves the regulation of water management and contributes to the protection against oxidative stress caused by drought.
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We reported earlier that 7B-1mutant in tomato (Solanum lycopersicum L., cv. Rutgers), an ABA overproducer, is defective in blue light (B) signaling leading to B-specific resistance to abiotic and biotic stresses. Using a... more
We reported earlier that 7B-1mutant in tomato (Solanum lycopersicum L., cv. Rutgers), an ABA overproducer, is defective in blue light (B) signaling leading to B-specific resistance to abiotic and biotic stresses. Using a methylation-sensitive amplified polymorphism (MSAP) assay, a number of genes were identified, which were differentially methylated between 7B-1 and its wild type (WT) seedlings in white (W), blue (B), red (R) lights and dark (D) or in re-sponse to exogenous ABA and mannitol-induced stresses. The genomic methylation level was almost similar in different lights between 7B-1 and WT seedlings, while significant dif-ferences were observed in response to stresses in D, but not B. Using a cDNA-AFLP assay, several transcripts were identified, which were differentially regulated between 7B-1 and WT by B or D or in response to stresses. Blue light receptors cryptochrome 1 and 2 (CRY1 and CRY2) and phototropin 1 and 2 (PHOT1 and PHOT2) were not affected by the 7B-1mutation at ...
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As a second messenger, calcium is involved in auxin signaling, and previous studies demonstrated that Arabidopsis CAX1 (Ca2+/H+ exchanger) is involved in the auxin transduction pathway. This study was performed to investigate the possible... more
As a second messenger, calcium is involved in auxin signaling, and previous studies demonstrated that Arabidopsis CAX1 (Ca2+/H+ exchanger) is involved in the auxin transduction pathway. This study was performed to investigate the possible role of auxin-binding proteins ABP1 and ABP4 in Ca2+/auxin-regulated growth in maize (Zea mays L.). We identified and cloned two AtCAX1 homologs in maize, ZCAX2 and ZCAX3. Using maize loss-of-function abp1 and abp4 mutants, the role of ABPs in Ca2+-dependent growth and in the Ca2+/auxin-regulated expression of the CAX genes was investigated in etiolated maize seedlings. Exogenous Ca2+ enhanced mesocotyl but not coleoptile growth in WT, abp1, abp4, and abp1/abp4 mutants, but the maximum stimulation was in abp4. As well, in the abp4 mutant, maximum accumulation of Ca2+ was observed when seedlings were exposed to exogenous Ca2+. In the mesocotyl of abp4 and double mutants, the expression of ZCAX3 was significantly reduced in the absence of exogenous C...
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List of the identified known miRNAs in WT and 7B-1 anthers. Table S2. List of the new miRNAs identified from WT anthers. Table S3. List of the new miRNAs identified from 7B-1 anthers. Table S4. List of miRNA-target cleavage sites. Table... more
List of the identified known miRNAs in WT and 7B-1 anthers. Table S2. List of the new miRNAs identified from WT anthers. Table S3. List of the new miRNAs identified from 7B-1 anthers. Table S4. List of miRNA-target cleavage sites. Table S5. List of tasiRNAs and their predicated target genes. Table S6. List of the identified TAS3-derived tasiRNAs from WT library. Table S7. List of the identified TAS3-derived tasiRNAs from 7B-1 library. Table S8. List of the primers used for RT-qPCR analysis. Table S9. List of the primers used for 5â ˛-RACE analysis. Table S10. List of the DIG-labeled oligo-probes used for in situ hybridization. (DOCX 676Â kb)
Hairpin structures of new miRNA precursors. Figure S2. 5â ˛- RACE validation of tasiARFs target genes in 7B-1 anther and stem. Figure S3. RT-qPCR validation of tasiARFs target genes in 7B-1 anther and stem. Figure S4. RT-qPCR validation... more
Hairpin structures of new miRNA precursors. Figure S2. 5â ˛- RACE validation of tasiARFs target genes in 7B-1 anther and stem. Figure S3. RT-qPCR validation of tasiARFs target genes in 7B-1 anther and stem. Figure S4. RT-qPCR validation of cysteine protease and polygalacturonase in 7B-1 anthers and stem. Figure S5. RT-qPCR validation of miR159 and GAMYBL1 in GA-treated 7B-1 anthers. Figure S6. Cytological study of anther development in 7B-1 and WT. (DOCX 4243Â kb)
Dark-induced growth (skotomorphogenesis) is primarily characterized by rapid elongation of the hypocotyl. We have studied the role of abscisic acid (ABA) during the development of young tomato (Solanum lycopersicum L.) seedlings. We... more
Dark-induced growth (skotomorphogenesis) is primarily characterized by rapid elongation of the hypocotyl. We have studied the role of abscisic acid (ABA) during the development of young tomato (Solanum lycopersicum L.) seedlings. We observed that ABA deficiency caused a reduction in hypocotyl growth at the level of cell elongation and that the growth in ABA-deficient plants could be improved by treatment with exogenous ABA, through which the plants show a concentration dependent response. In addition, ABA accumulated in dark-grown tomato seedlings that grew rapidly, whereas seedlings grown under blue light exhibited low growth rates and accumulated less ABA. We demonstrated that ABA pro-motes DNA endoreduplication by enhancing the expression of the genes encoding inhibi-tors of cyclin-dependent kinases SlKRP1 and SlKRP3 and by reducing cytokinin levels. These data were supported by the expression analysis of the genes which encode enzymes involved in ABA and CK metabolism. Our resul...
A recessive single gene mutant, 7B-1, in tomato was originally selected for its photoperiod-dependent male sterility. The 7B-1 mutant also has some pleiotropic effects including reduced light-induced inhibition, i.e. de-etiolation, of the... more
A recessive single gene mutant, 7B-1, in tomato was originally selected for its photoperiod-dependent male sterility. The 7B-1 mutant also has some pleiotropic effects including reduced light-induced inhibition, i.e. de-etiolation, of the hypocotyl in long days (LD), increased seed size and weight, and reduced transpiration rate. These traits led us to investigate the sensitivity of 7B-1 to exogenous hormones and the interaction of these responses with daylength. In LD, but not in short days (SD), 7B-1 was more sensitive than wild-type (WT) to exogenous abscisic acid (ABA) for inhibition of seed germination, root elongation and transpiration rate. 7B-1 mutant also exhibited reduced responses to exogenous gibberellin (GA(3)) for hypocotyl elongation, and to inhibitors of GA biosynthesis for seed germination and root and hypocotyl elongation. 7B-1 hypocotyls contained a higher level of endogenous ABA than WT in both photoperiods, although ABA levels were higher in LD than in SD. In co...
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The single-gene male-sterile 7B-1 mutant in tomato (Lycopersicon esculentum Mill.) shows reduced de-etiolation of hypocotyl growth, has an elevated level of endogenous abscisic acid (ABA) and reduced amounts of growth-active gibberellins... more
The single-gene male-sterile 7B-1 mutant in tomato (Lycopersicon esculentum Mill.) shows reduced de-etiolation of hypocotyl growth, has an elevated level of endogenous abscisic acid (ABA) and reduced amounts of growth-active gibberellins (GAs), is supersensitive to exogenous ABA, and is resistant to abiotic stresses in light but not in the dark. The existence of crosstalk between light signaling and plant hormones, and the interaction of ABA and GA biosynthetic pathways with ethylene, led us to investigate the possible role of ethylene in the 7B-1 mutant. In the dark, 7B-1 seedlings exhibited the normal triple response to 1-aminocyclopropane–1-carboxylic acid (ACC), an ethylene precur-sor, similar to the wild type. In light, however, hypocotyl growth of mutant seedlings was more sensitive to ACC but less sensitive to the inhibitors of ethylene’s action, such as silver thiosulfate, than the wild type. The 7B-1 mutant seedlings produced reduced levels of ethylene, which could account ...
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Ambient air pollution is a problematic in several countries in the European Union, not excepting the Czech Republic. One of the areas with the most polluted air by particulate matter, is Ostrava district. The district combines several... more
Ambient air pollution is a problematic in several countries in the European Union, not excepting the Czech Republic. One of the areas with the most polluted air by particulate matter, is Ostrava district. The district combines several sources of particulate matter emissions. This paper is analysing the trend of particulate matter ambient air pollution in the area during the years 2004 – 2017. Attention is focused on the legal frame, measurement network, sources of emission and particulate matter values. The second part of the thesis is examining possible and preferred futures of the particulate matter air pollution trend and it is proposing the steps which need to be done to achieve the preferred scenario.
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The single-gene male-sterile 7B-1 mutant in tomato (Lycopersicon esculentum Mill.) shows reduced de-etiolation of hypocotyl growth, has an elevated level of endogenous abscisic acid (ABA) and reduced amounts of growth-active gibberellins... more
The single-gene male-sterile 7B-1 mutant in tomato (Lycopersicon esculentum Mill.) shows reduced de-etiolation of hypocotyl growth, has an elevated level of endogenous abscisic acid (ABA) and reduced amounts of growth-active gibberellins (GAs), is supersensitive to exogenous ABA, and is resistant to abiotic stresses in light but not in the dark. The existence of crosstalk between light signaling and plant hormones, and the interaction of ABA and GA biosynthetic pathways with ethylene, led us to investigate the possible role of ethylene in the 7B-1 mutant. In the dark, 7B-1 seedlings exhibited the normal triple response to 1-aminocyclopropane–1-carboxylic acid (ACC), an ethylene precursor, similar to the wild type. In light, however, hypocotyl growth of mutant seedlings was more sensitive to ACC but less sensitive to the inhibitors of ethylene’s action, such as silver thiosulfate, than the wild type. The 7B-1 mutant seedlings produced reduced levels of ethylene, which could account f...
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A major problem of in vitro plant culture techniques is chronic contamination by microorganisms. Calli derived from basal parts of leaves of Allium longicuspis Regel (Alliaceae) and cultured in a medium without antibiotic contain most... more
A major problem of in vitro plant culture techniques is chronic contamination by microorganisms. Calli derived from basal parts of leaves of Allium longicuspis Regel (Alliaceae) and cultured in a medium without antibiotic contain most probably latent contaminating microorganisms. These calli were used as the source material for isolation and culture of protoplasts. Isolated protoplasts were cultured in the presence of the antibiotic ciprofloxacin, and the protoplast viability, cell wall regeneration and cell division were studied as a function of the antibiotic concentration. Whatever the antibiotic concentration, protoplast-derived cells kept significantly higher viability for at least 3 weeks compared with those cultured without antibiotic. As to cell wall regeneration after 2 d, it was not affected by the antibiotic except at the highest concentration tested (100 mg l-1). Sporadic first cell division was observed after 2-6 d of culture in the presence of ciprofloxacin while, in its absence, cell division was never apparent before 10 d of culture.
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The 7B-1 tomato (Solanum lycopersicum L. cv Rutgers) is a male-sterile mutant with enhanced tolerance to abiotic stress, which makes it a potential candidate for hybrid seed breeding and stress engineering. To underline the molecular... more
The 7B-1 tomato (Solanum lycopersicum L. cv Rutgers) is a male-sterile mutant with enhanced tolerance to abiotic stress, which makes it a potential candidate for hybrid seed breeding and stress engineering. To underline the molecular mechanism regulating the male-sterility in 7B-1, transcriptomic profiles of the 7B-1 male-sterile and wild type (WT) anthers were studied using mRNA sequencing (RNA-Seq). In total, 768 differentially expressed genes (DEGs) were identified, including 132 up-regulated and 636 down-regulated transcripts. Gene ontology (GO) enrichment analysis of DEGs suggested a general impact of the 7B-1 mutation on metabolic processes, such as proteolysis and carbohydrate catabolic process. Sixteen candidates with key roles in regulation of anther development were subjected to further analysis using qRT-PCR and in situ hybridization. Cytological studies showed several defects associated with anther development in the 7B-1 mutant, including unsynchronized anther maturatio...
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The 7B-1 tomato line (Solanum lycopersicum cv. Rutgers) is a photoperiod-sensitive male-sterile mutant, with potential application in hybrid seed production. Small RNAs (sRNAs) in tomato have been mainly characterized in fruit development... more
The 7B-1 tomato line (Solanum lycopersicum cv. Rutgers) is a photoperiod-sensitive male-sterile mutant, with potential application in hybrid seed production. Small RNAs (sRNAs) in tomato have been mainly characterized in fruit development and ripening, but none have been studied with respect to flower development and regulation of male-sterility. Using sRNA sequencing, we identified miRNAs that are potentially involved in anther development and regulation of male-sterility in 7B-1 mutant. Two sRNA libraries from 7B-1 and wild type (WT) anthers were sequenced and thirty two families of known miRNAs and 23 new miRNAs were identified in both libraries. MiR390, miR166, miR159 were up-regulated and miR530, miR167, miR164, miR396, miR168, miR393, miR8006 and two new miRNAs, miR#W and miR#M were down-regulated in 7B-1 anthers. Ta-siRNAs were not differentially expressed and likely not associated with 7B-1 male-sterility. miRNA targets with potential roles in anther development were validat...
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We reported earlier that 7B-1 mutant in tomato (Solanum lycopersicum L., cv. Rutgers), an ABA overproducer, is defective in blue light (B) signaling leading to B-specific resistance to abiotic and biotic stresses. Using a... more
We reported earlier that 7B-1 mutant in tomato (Solanum lycopersicum L., cv. Rutgers), an ABA overproducer, is defective in blue light (B) signaling leading to B-specific resistance to abiotic and biotic stresses. Using a methylation-sensitive amplified polymorphism (MSAP) assay, a number of genes were identified, which were differentially methylated between 7B-1 and its wild type (WT) seedlings in white (W), blue (B), red (R) lights and dark (D) or in response to exogenous ABA and mannitol-induced stresses. The genomic methylation level was almost similar in different lights between 7B-1 and WT seedlings, while significant differences were observed in response to stresses in D, but not B. Using a cDNA-AFLP assay, several transcripts were identified, which were differentially regulated between 7B-1 and WT by B or D or in response to stresses. Blue light receptors cryptochrome 1 and 2 (CRY1 and CRY2) and phototropin 1 and 2 (PHOT1 and PHOT2) were not affected by the 7B-1 mutation at ...
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Modern corn ( Zea mays L.) varieties have been selected for their ability to maintain productivity in dense plantings. We have tested the possibility that the physiological consequence of the selection of the modern hybrid, 3394, for... more
Modern corn ( Zea mays L.) varieties have been selected for their ability to maintain productivity in dense plantings. We have tested the possibility that the physiological consequence of the selection of the modern hybrid, 3394, for increased crop yield includes changes in responsiveness to auxin and light. Etiolated seedlings in the modern line are shorter than in an older hybrid, 307, since they produce shorter coleoptile, mesocotyl, and leaves (blade as well as sheath). Etiolated 3394 seedlings, as well as isolated mesocotyl and sheath segments, were less responsive to auxin and an inhibitor of polar auxin transport, N-1-naphthylphthalamic acid (NPA). Reduced response of 3394 to auxin was associated with less reduction of elongation growth by light (white, red, far-red, blue) than in 307, whereas the activity of polar auxin transport (PAT) and its reduction by red or far-red light was similar in both genotypes. NPA reduced PAT in etiolated 3394 seedlings much less than in 307. A...
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It was reported earlier that 7B-1 mutant in tomato (Solanum lycopersicum L.), an ABA overproducer, is defective in blue light (BL) signaling leading to BL-specific resistance to abiotic and biotic stresses. In this work, we examine... more
It was reported earlier that 7B-1 mutant in tomato (Solanum lycopersicum L.), an ABA overproducer, is defective in blue light (BL) signaling leading to BL-specific resistance to abiotic and biotic stresses. In this work, we examine responses of stomata to blue, red and white lights, fusicoccin, anion channel blockers (anthracene-9-carboxylic acid; 9-AC and niflumic acid; NIF) and ABA. Our results showed that the aperture of 7B-1 stomata does not increase in BL, suggesting that 7B-1 mutation impairs an element of BL signaling pathway involved in stomatal opening. Similar stomatal responses of 7B-1 and wild type (WT) to fusicoccin or 9-AC points out that activity of H(+)-ATPase and 9-AC-sensitive anion channels per se is not likely affected by the mutation. Since 9-AC restored stomatal opening of 7B-1 in BL, it seems that 9-AC and BL could block similar type of anion channels. The stomata of both genotypes did not respond to NIF neither in darkness nor in any light conditions tested. In light, 9-AC but not NIF restored stomatal opening inhibited by ABA in WT and 7B-1. We suggest that in comparison to WT, the activity of S-type anion channels in 7B-1 is more promoted by increased ABA content, and less reduced by BL, because of the mutant resistance to BL.
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ABSTRACT A highly embryogenic cell suspension of alfalfa derived from a genotype sensitive to Fusarium oxysporum was successfully used for selection in vitro for resistance to culture filtrates of F. oxysporum, F. solani and F. avenaceum.... more
ABSTRACT A highly embryogenic cell suspension of alfalfa derived from a genotype sensitive to Fusarium oxysporum was successfully used for selection in vitro for resistance to culture filtrates of F. oxysporum, F. solani and F. avenaceum. Fifty two stable resistant cell lines were obtained and 500 plants regenerated from them. Among the 167 regenerants tested under glass there were 12–20% more plants with increased resistance to pathogens than in the group of plants regenerated from a control cell line. It was also found that the cell suspension cultures derived from genotypes of alfalfa with increased resistance to Fusarium spp. better tolerated filtrates of the pathogen. The results of a comparison of virulence of individual isolates of several species of Fusarium with toxicity of their filtrates to plants in vivo and in cell cultures were not unequivocal.
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In maize, at least five auxin-binding proteins (ABPs) have been identified, yet their functions remain unclear. The present study reports the use of maize abp1, abp4, and abp1abp4 mutants to investigate the role of ABPs during maize... more
In maize, at least five auxin-binding proteins (ABPs) have been identified, yet their functions remain unclear. The present study reports the use of maize abp1, abp4, and abp1abp4 mutants to investigate the role of ABPs during maize growth and development. Single and double abp mutant plants grown in a greenhouse differ from the wild type (WT) in their leaf declination and leaf blade growth. The effect of the dark (D), blue light (BL), red light (RL), and exogenous auxin on the development of mutant seedlings was also studied. Relative to WT, etiolated mutant seedlings were shorter and showed a reduced responsiveness to exogenous auxin. In BL or RL, the responsiveness of maize seedlings to auxin was distinctly less than in D. The reducing effect of light on seedling responsiveness to auxin is mediated at least by phytochromes. The suppression of ABP1 and (or) ABP4 led to a distinct accumulation of free indole-3-acetic acid (IAA) in etiolated and light-grown seedling organs. We concl...