| 1. |
- Carlsson, Anders, et al.
(författare)
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Cell membrane integrity, callose accumulation, and root growth in aluminum-stressed sorghum seedlings
- 2014
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Ingår i: Biologia Plantarum. - : Institute of Experimental Botany. - 0006-3134 .- 1573-8264. ; 58, s. 768-772
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Tidskriftsartikel (refereegranskat)abstract
- Aluminum stress usually reduces plant root growth due to the accumulation of Al in specific zones of the root apex. The objectives of this study were to determine the localization of Al in the root apex of Sorghum bicolor (L.) Moech. and its effects on membrane integrity, callose accumulation, and root growth in selected cultivars. Seedlings were grown in a nutrient solution containing 0, 27, or 39 mu M Al3+ for 24, 48, and 120 h. The Al stress significantly reduced root growth, especially after 48 and 120 h of exposure. A higher Al accumulation, determined by fluorescence microscopy after staining with a Morin dye, occurred in the root extension zone of the sensitive cultivar than in the tolerant cultivar. The membrane damage and callose accumulation were also higher in the sensitive than resistant cultivar. It was concluded that the Al stress significantly reduced root growth through the accumulation of Al in the root extension zone, callose accumulation, and impairment of plasma membrane integrity.
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| 2. |
- Hajduch, M, et al.
(författare)
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An electrophoretic analysis of the seed protein body proteins from Pinus nigra
- 2001
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Ingår i: Biologia plantarum. - 0006-3134 .- 1573-8264. ; 44:1, s. 137-140
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Tidskriftsartikel (refereegranskat)abstract
- Protein bodies (PBs) of European black pine (Pirus nigra Am.) were isolated from mature seeds. Extracted soluble matrix proteins and crystalloid proteins PBs proteins were investigated by SDS-PAGE electrophoresis in presence and absence of 2-mercaptoethanol. The proteins of molecular masses 16, 17, 18, 61 and 65 kDa were presented only in crystalloid protein samples. Only 15 kDa protein was present in soluble matrix proteins and not in crystalloid proteins. Another protein bands were present in both soluble matrix and crystalloid proteins. 20, 37, 38, 39 and 48 kDa proteins were strongly visible among crystalloid proteins. Bands of 23 and 32 kDa were more visible in soluble matrix protein samples. Different composition in crystalloid proteins was found in absence of 2-mercaptoethanol: no proteins with molecular mass 71 kDa and more proteins in soluble matrix. In case of crystalloid proteins we detected 7 protein bands in interval from 71 to 212 kDa.
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| 3. |
- Hrib, J, et al.
(författare)
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Protein bodies in the pine megagametophyte in vitro culture : ultrastructural, histochemical and electrophoretic observations
- 2000
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Ingår i: Biologia plantarum. - 0006-3134 .- 1573-8264. ; 43:3, s. 329-336
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Tidskriftsartikel (refereegranskat)abstract
- The megagametophytes of the European black pine (Pinus nigra Am.) were cultured on modified MS medium. After 10 d, protein bodies showed well-marked degradation on freeze-etched replicas and in preparations observed by scanning electron microscopy. After 20 d of cultivation, the megagametophyte cells were completely empty. Proteins secreted into the agar medium were determined by electrophoresis and 15 different proteins, in the range of 6.5 to 71 kDa, were identified.
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| 4. |
- Kumar, Dhananjay
(författare)
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Identification of novel hypoxia-responsive factors in deep-water rice conferring tolerance to flood during germination
- 2020
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Ingår i: Biologia Plantarum. - : Institute of Experimental Botany. - 0006-3134 .- 1573-8264. ; 64, s. 244-252
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Tidskriftsartikel (refereegranskat)abstract
- Flood in rice fields at the time of seed sowing and early seedling establishment causes extensive crop loss due to the inability of the seeds to tolerate and overcome submergence. In the present study, rice genotypes from Assam, India tolerant to hypoxia during germination were identified through systematic screening of deep-water rice genotype collection from flood-prone ecosystem of Brahmaputra river valley. The difference in tolerance to hypoxia during germination within the species provides scope for identification of novel hypoxia-responsive factors involved in tolerance as mechanism of tolerance may not be conserved across tolerant gennplasms. Tolerant genotypes were further subjected to physiological and molecular characterization. Growth rate kinetics in tolerant genotypes new Rangdhakekua bao (RKB) and cultivar Khao Hlan On (KHO) from International Rice Research Institute (IRRI) used as positive control exhibited stronger escape strategy under hypoxic condition compared to sensitive genotype IR-64 (negative control). Activities of a-amylase and pyruvate decarboxylase were significantly higher in RKB and KHO than in IR-64, while no significant difference was observed in the alcohol dehydrogenase activity. Reverse transcription quantitative PCR confirmed increased amounts of transcripts of sucrose nonfermenting I related protein kinase, myeloblastosis-related protein S1, rice amylase 3D, and trehalose phosphate phosphatase 7 genes, which are known to be involved in hypoxia signaling cascade. Besides, transcription factors (TFs) like ethylene responce factors 71 and 63, ethylene insensitive 3-like la and proteins like cxpansins A7 and A2, which are involved in cell elongation had also significantly higher amounts in RKB compared to IR64. Additional factors that include TFs like ERF71 and FRF63 that shows perturbation at transcription even within tolerant genotypes might constitute the genotype-specific regulation, evolved as a part of its adaptive mechanism to survive under submerged conditions.
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| 5. |
- Landberg, Tommy, et al.
(författare)
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Strategies of cadmium and zinc resistance in willow by regulation of net accumulation
- 2011
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Ingår i: Biologia plantarum. - : Institute of Experimental Botany. - 0006-3134 .- 1573-8264. ; 55:1, s. 133-140
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Tidskriftsartikel (refereegranskat)abstract
- This work was performed to find out if metal resistant clones of Salix viminalis L. are capable to achieve high resistance to the metals by regulating their net accumulation. Salix clones with low or high resistance in combination with low or high accumulation capacity of either Zn or Cd were cultivated from cuttings in nutrient solution. The investigation included leakage and uptake experiments using (65)Zn or (109)Cd and analysis of root cation exchange capacity (CEC). Some plants were pre-treated with unlabeled 0.5 mu M Cd or 2.5 mu M Zn 24 h prior to the experiments to induce possible tolerance mechanisms. To find out if the regulation was a metabolic process, experiments were also performed with 2,4-dinitrophenol (DNP). Clones with high resistance and low Cd accumulation had higher efflux of Cd compared to the other clones, in both untreated and Cd pre-treated plants. This indicates a constitutive property to lower Cd accumulation by high Cd leakage. Pre-treatment with 0.5 mu M Cd diminished the Cd net uptake to a level near zero in all clones, likely to be due to decreased the Cd uptake. In contrast, resistant clones with high Cd accumulation had the highest root CEC, which may be used to bind up Cd in the free space. No clear regulation of Zn net uptake was found in Zn-resistant clones. Pre-treatment with Zn decreased the uptake of Zn into the free space in Zn-resistant clones. The resistant high-accumulating clones, however, showed the highest leakage of Zn in both untreated and pre-treated plants, a constitutive process not related to high accumulation. Neither the influx nor the efflux of Cd or Zn was affected by DNP indicating passive transport across the plasma membrane.
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| 6. |
- Larsson Jönsson, Helene, et al.
(författare)
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Effects of pH and nitrogen on cadmium uptake in potato
- 2013
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Ingår i: Biologia Plantarum. - : Institute of Experimental Botany. - 0006-3134 .- 1573-8264. ; 57, s. 788-792
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Tidskriftsartikel (refereegranskat)abstract
- This study investigated the effects of pH and nitrogen form and concentration on cadmium (Cd) uptake by potato (Solanum tuberosum L.) grown in hydroponic culture. Potato plants grown in a pH-buffered nutrient solution for 10 d were exposed for 24 h to 25 nM CdCl2 labelled with Cd-109. Plants showed a significantly higher Cd uptake and accumulation at pH 6.5 than at pH 4.5 and 5.5. Nitrogen supplied as nitrate (NO3 (-)) generally resulted in a higher Cd uptake and accumulation than N supplied as ammonium (NH4 (+)). This effect was most pronounced at pH 6.5. The N concentration increasing from 6.5 to 26 mM resulted in a decreased Cd influx when either NO3 (-) or NH4 (+) was used. Cd translocation to the shoot was increased when NO3 (-) was used as the sole N source. In conclusion, pH had a strong influence on Cd uptake by roots and N form is especially important for Cd translocation within the potato plant.
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| 7. |
- Valdés, A.E., et al.
(författare)
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Developmental stage as a possible factor affecting cytokinin content and cytokinin dehydrogenase activity in Pinus sylvestris.
- 2007
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Ingår i: Biologia plantarum. - : Institute of Experimental Botany. - 0006-3134 .- 1573-8264. ; 51:1, s. 193-197
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Tidskriftsartikel (refereegranskat)abstract
- In the present study cytokinin dehydrogenase (CKX) activity was for the first time found in a conifer species, Pinus sylvestris. The activities were correlated with the endogenous cytokinin contents. Several enzyme substrates and two different electron acceptors were used to search for the enzyme activity in the extract from seeds, seedlings and plantlets. The highest specific activity was found in one-year-old plantlets with isopentenyladenine as the substrate and 2,6-dichlorophenolindophenol as the electron acceptor, at pH 8. An enhancement in the CKX specific activity corresponded to increasing contents of cytokinins, mainly isopentenyladenine and isopentenyladenosine, indicating that the enzyme activity is affected by the endogenous supply of cytokinins. CKX affinity for the ribosylated form of isopentenyladenine was dependent on the developmental stage, being higher in seeds than in seedlings, and not detectable in plantlets. The results are indicative of the presence of different isoenzymes throughout the development.
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| 8. |
- Österås, Ann Helén, et al.
(författare)
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Interactions between Ca and Cu or Cd in Norway spruce
- 2006
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Ingår i: Biologia plantarum. - : SpringerLink. - 0006-3134 .- 1573-8264. ; 50:4, s. 647-652
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Tidskriftsartikel (refereegranskat)abstract
- The accumulation of calcium (Ca), copper (Cu) and cadmium (Cd) in roots and stem of Norway spruce ( Picea abies [L.] Karst) was examined. Two-year-old Norway spruce seedlings were treated with elevated concentrations of Ca, Cd or Cu, or as combinations of Ca with Cu or Cd in nutrient solutions for three months. The stem was divided into bark, wood formed during the treatment period (new wood), and wood formed before the treatment period (old wood). The accumulation of the metals in stem and roots increased with addition of the respective metal into nutrient solution. Addition of Cu decreased the accumulation of Ca in roots and wood, and Ca addition decreased the accumulation of Cu in the new wood. By adding Ca in combination with Cu the accumulation of Cu in the stem was decreased even more by Ca and the negative effect of Cu on the Ca content in the stem was diminished. Addition of Cd decreased the accumulation of Ca in wood, especially the old wood, and Ca addition decreased the accumulation of Cd in roots, bark and new wood. By adding Ca in combination with Cd the Ca content was reduced in the bark, instead of in the old wood.
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| 9. |
- Sundmark, Björn
(författare)
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Editorial
- 2015
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Ingår i: Bookbird. - : International Institute for Children's Literature and Reading Research. - 0006-7377 .- 1918-6983. ; 53:2, s. 2-3
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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