scholarly journals Identification of Barley (Hordeum vulgare L.) Autophagy Genes and Their Expression Levels during Leaf Senescence, Chronic Nitrogen Limitation and in Response to Dark Exposure

Agronomy ◽  
2016 ◽  
Vol 6 (1) ◽  
pp. 15 ◽  
Author(s):  
Liliana Avila-Ospina ◽  
Anne Marmagne ◽  
Fabienne Soulay ◽  
Céline Masclaux-Daubresse
Keyword(s):  
Hordeum Vulgare ◽  
Leaf Senescence ◽  
Nitrogen Limitation ◽  
Hordeum Vulgare L ◽  
Expression Levels ◽  
Dark Exposure

scholarly journals Regulation of senescence-associated protease genes by sulphur availability according to barley (Hordeum vulgare L.) phenological stage

2020 ◽  
Vol 126 (3) ◽  
pp. 435-444
Author(s):  
Cintia G Veliz ◽  
Maria Victoria Criado ◽  
María Florencia Galotta ◽  
Irma N Roberts ◽  
Carla Caputo
Keyword(s):  
Hordeum Vulgare ◽  
Serine Protease ◽  
Leaf Senescence ◽  
Leaf Age ◽  
Protein Composition ◽  
Cysteine Proteases ◽  
Vegetative Stage ◽  
Protease Gene ◽  
Hordeum Vulgare L ◽  
Sulphur Deficiency

Abstract Background and Aims Proteases are responsible for protein degradation during leaf senescence, allowing nutrients to be redirected to sink tissues. In a previous work, we reported that sulphur deficiency produced a delay in the leaf senescence of barley (Hordeum vulgare L.) plants, at both vegetative and reproductive stages. In this work, we analyse the effect of sulphur deficiency on the expression of several genes coding for proteases of different catalytic groups, which have been strongly associated with leaf senescence. Methods Four independent experiments were performed in order to impose low sulphur availability conditions: one of steady-state sulphur deficiency during the vegetative stage and three of sulphur starvation during vegetative and reproductive stages. Key Results Sulphur deficiency inhibited or reduced the senescence-associated induction of seven of the eight proteases analysed. Their induction, as well as senescence and phloem amino acid remobilization, could be achieved with senescence inducers such as methyl-jasmonate (a hormonal stimulus) and darkness, but with different rates of induction dependent on each gene. Sulphur deficiency also exerted an opposite effect on the expression of two cysteine-protease genes (HvSAG12 and HvLEGU) as well as on one serine-protease gene (HvSUBT) according to leaf age and plant phenological stages. All three genes were induced in green leaves but were repressed in senescent leaves of sulphur-deficient plants at the vegetative stage. At the reproductive stage, both cysteine-proteases were only repressed in senescent leaves, while the serine-protease was induced in green and senescent leaves by sulphur deficiency. Conclusions Our results highlight the relevance of adequate sulphur nutrition in order to ensure leaf senescence onset and induction of protease genes, which will consequently impact on grain protein composition and quality. In addition, our results provide evidence that leaf age, plant developmental stage and the nature of the stress modulate the sulphur responses.

scholarly journals Effect of Fe3O4 and CuO Nanoparticles on Morphology, Genotoxicity, and miRNA Expression on Different Barley (Hordeum vulgare L.) Genotypes

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Anastasija Petrova ◽  
Ilona Plaksenkova ◽  
Inese Kokina ◽  
Marija Jermaļonoka
Keyword(s):  
Hordeum Vulgare ◽  
Mirna Expression ◽  
Genome Stability ◽  
Cuo Nanoparticles ◽  
Hordeum Vulgare L ◽  
Expression Levels ◽  
Fresh Biomass ◽  
Reduced Genome ◽  
Cuo Nps ◽  
Fe3o4 Nps

Metal nanoparticles (NPs) have an influence on plant growth and development. They can alter plant shoot and root length, fresh biomass production, and even influence the genome. Nanoparticles are also able to affect expression levels of plant microRNAs. MicroRNAs are able to protect plants from biotic stress, including pathogens which cause powdery mildew. In this study, Hordeum vulgare L. varieties “Marthe” and “KWS Olof” were grown in hydroponics with magnetic iron oxide (Fe3O4) and copper oxide (CuO) NPs added at 17, 35, and 70 mg/L. Plant morphology, genotoxicity, and expression of miR156a were investigated. The Fe3O4 and CuO NPs demonstrated different effects on the barley varieties, namely, Fe3O4 nanoparticles increased plant shoot and root lengths and fresh biomass, while CuO nanoparticles decreased them. CuO NPs presence caused larger changes on barley genome compared to Fe3O4 NPs. Thus, Fe3O4 NPs reduced genome stability to 72% in the “Marthe” variety and to 76.34% in the “KWS Olof” variety, while CuO NPs reduced genome stability to 53.33% in “Marthe” variety and in the “KWS Olof” variety to 68.81%. The miR156a expression levels after Fe3O4 NPs treatment did not change in the “Marthe” variety, but increased in the “KWS Olof” variety, while CuO NPs treatment increased miRNA expression levels in the “Marthe” variety but decrease them in the “KWS Olof” variety. As NPs are able to influence miRNA expression and miRNAs can affect the plant resistance, obtained results suggest that tested NPs may alter plant resistance response to pathogens.

Ultrastructure and Senescence in an Achloroplastic Mutant of Hordeum vulgare L. cv. Dyan

1992 ◽  
Vol 50 (1) ◽  
pp. 844-845
Author(s):  
R.H.M. Cross ◽  
C.E.J. Botha ◽  
A.K. Cowan ◽  
B.J. Hartley
Keyword(s):  
Cell Wall ◽  
Hordeum Vulgare ◽  
Leaf Tissue ◽  
Ultrastructural Changes ◽  
Hordeum Vulgare L ◽  
Mesophyll Cells ◽  
Lethal Mutant ◽  
Cytoplasmic Matrix ◽  
Close Proximity ◽  
Pinocytotic Vesicles

Senescence is an ordered degenerative process leading to death of individual cells, organs and organisms. The detection of a conditional lethal mutant (achloroplastic) of Hordeum vulgare has enabled us to investigate ultrastructural changes occurring in leaf tissue during foliar senescence.Examination of the tonoplast structure in six and 14 day-old mutant tissue revealed a progressive degeneration and disappearance of the membrane, apparently starting by day six in the vicinity of the mitochondria associated with the degenerating proplastid (Fig. 1.) where neither of the plastid membrane leaflets is evident (arrows, Fig. 1.). At this stage there was evidence that the mitochondrial membranes were undergoing retrogressive changes, coupled with disorganization of cristae (Fig. 2.). Proplastids (P) lack definitive prolamellar bodies. The cytoplasmic matrix is largely agranular, with few endoplasmic reticulum (ER) cisternae or polyribosomal aggregates. Interestingly, large numbers of actively-budding dictysomes, associated with pinocytotic vesicles, were observed in close proximity to the plasmalemma of mesophyll cells (Fig. 3.). By day 14 however, mesophyll cells showed almost complete breakdown of subcellular organelle structure (Fig. 4.), and further evidence for the breakdown of the tonoplast. The final stage of senescence is characterized by the solubilization of the cell wall due to expression and activity of polygalacturonase and/or cellulose. The presence of dictyosomes with associated pinocytotic vesicles formed from the mature face, in close proximity to both the plasmalemma and the cell wall, would appear to support the model proposed by Christopherson for the secretion of cellulase. This pathway of synthesis is typical for secretory glycoproteins.

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