scholarly journals NEW EXAMPLE OF USE OF LENS CULINARIS FOR PHYTOASSAY OF ECOTOXICITY OF CHEMICALS

2021 ◽  
Vol 11 (01) ◽  
pp. 17-20
Author(s):  
X.Cai X.Cai ◽  
Sergei Ostroumov
Keyword(s):  
Root Length ◽  
Synthetic Detergent ◽  
Lens Culinaris ◽  
Root Elongation ◽  
Higher Plants ◽  
Laundry Detergent ◽  
Environmental Toxicology ◽  
Higher Plant ◽  
Liquid Laundry Detergent ◽  
Plant Seedlings

Previously, toxicity of some synthetic detergents (including laundry detergents) to the plant seedlings of several species of terrestrial higher plants was discovered in research conducted at Moscow University by S.A.Ostroumov. A new example of toxicity of a laundry detergent to plant seedlings was found in this study. The synthetic detergent tested, namely the liquid laundry detergent (LLD) “Blue Moon”, which was manufactured by Blue Moon Group Co, Ltd (Guangzhou, China), produced noticeable phytotoxic effects on the plant seedlings of the terrestrial higher plant Lens culinaris. This detergent at the concentrations 0.5 % - 1% induced a pronounced decrease in the average root length of the seedlings of Lens culinaris. The concentration 5% was lethal to Lens culinaris. Keywords: ecotoxicity, detergent, bioassay, terrestrial higher plants, plant seedlings, root elongation, phytotoxicity, environmental toxicology, Lens culinaris

scholarly journals OsJAZ11 regulates phosphate starvation responses in rice

Planta ◽  
2021 ◽  
Vol 254 (1) ◽  
Author(s):  
Bipin K. Pandey ◽  
Lokesh Verma ◽  
Ankita Prusty ◽  
Ajit Pal Singh ◽  
Malcolm J. Bennett ◽  
...  
Keyword(s):  
Jasmonic Acid ◽  
Root Length ◽  
Root Elongation ◽  
Terminal Region ◽  
Physical Interaction ◽  
Plant Signaling ◽  
Functional Connections ◽  
Growth Inhibitory ◽  
Expression Studies ◽  
Ja Signaling

Abstract Main conclusion OsJAZ11 regulates phosphate homeostasis by suppressing jasmonic acid signaling and biosynthesis in rice roots. Abstract Jasmonic Acid (JA) is a key plant signaling molecule which negatively regulates growth processes including root elongation. JAZ (JASMONATE ZIM-DOMAIN) proteins function as transcriptional repressors of JA signaling. Therefore, targeting JA signaling by deploying JAZ repressors may enhance root length in crops. In this study, we overexpressed JAZ repressor OsJAZ11 in rice to alleviate the root growth inhibitory action of JA. OsJAZ11 is a low phosphate (Pi) responsive gene which is transcriptionally regulated by OsPHR2. We report that OsJAZ11 overexpression promoted primary and seminal root elongation which enhanced Pi foraging. Expression studies revealed that overexpression of OsJAZ11 also reduced Pi starvation response (PSR) under Pi limiting conditions. Moreover, OsJAZ11 overexpression also suppressed JA signaling and biosynthesis as compared to wild type (WT). We further demonstrated that the C-terminal region of OsJAZ11 was crucial for stimulating root elongation in overexpression lines. Rice transgenics overexpressing truncated OsJAZ11ΔC transgene (i.e., missing C-terminal region) exhibited reduced root length and Pi uptake. Interestingly, OsJAZ11 also regulates Pi homeostasis via physical interaction with a key Pi sensing protein, OsSPX1. Our study highlights the functional connections between JA and Pi signaling and reveals JAZ repressors as a promising candidate for improving low Pi tolerance of elite rice genotypes.

Identification and characterization of novel QTL conferring internal detoxification of aluminum in soybean

2021 ◽  
Author(s):  
Yang Li ◽  
Heng Ye ◽  
Li Song ◽  
Tri D Vuong ◽  
Qijian Song ◽  
...  
Keyword(s):  
Root Length ◽  
Root Elongation ◽  
Primary Root ◽  
Pedigree Analysis ◽  
Length Ratio ◽  
Root Tip ◽  
Root Initiation ◽  
Al Tolerance ◽  
Al Stress ◽  
Root Length Ratio

Abstract Aluminum (Al) toxicity inhibits soybean root growth, leading to insufficient water and nutrient uptake. In this research, two soybean lines (Magellan and PI 567731) were identified differing in Al tolerance as determined by primary root length ratio (PRL_Ratio), total root length ratio (TRL_Ratio), and root tip number ratio (RTN_Ratio) under Al stress compared to unstressed controlled conditions. Serious root necrosis was observed in PI 567731, but not in Magellan under Al stress. An F8 recombinant inbred line population derived from a cross between Magellan and PI 567731 was used to map the quantitative trait loci (QTL) for Al-tolerance. Three QTL on chromosomes 3, 13, and 20, with tolerant-alleles from Magellan, were identified. qAl_Gm13 and qAl_Gm20, explained large phenotypic variations (13-27%) and played roles in maintaining root elongation. qAl_Gm03 was involved in maintaining root initiation under Al stress. These results suggested the importance of using the parameters of root elongation and root initiation in Al tolerance studies. In addition, qAl_Gm13 and qAl_Gm20 were confirmed in near-isogenic backgrounds and were identified to epistatically regulate Al tolerance in internal detoxification instead of Al 3+ exclusion. The candidate genes for qAl_Gm13 and qAl_Gm20 were suggested by analyzing a previous RNA-seq study. Phylogenetic and pedigree analysis identified the tolerant alleles of both loci derived from the US ancestor line, A.K.[FC30761], originally from China. Our results provide novel genetic resources for breeding Al-tolerant soybeans and suggest that the internal detoxification contributes to soybean tolerance to excessive soil Al.

Measurement of ferrochelatase activity using a novel assay suggests that plastids are the major site of haem biosynthesis in both photosynthetic and non-photosynthetic cells of pea (Pisum sativum L.)

2002 ◽  
Vol 362 (2) ◽  
pp. 423-432 ◽  
Author(s):  
Johanna E. CORNAH ◽  
Jennifer M. ROPER ◽  
Davinder Pal SINGH ◽  
Alison G. SMITH
Keyword(s):  
Ferrous Iron ◽  
Specific Activity ◽  
Higher Plants ◽  
Protoporphyrin Ix ◽  
Chlorophyll Synthesis ◽  
Marker Enzyme ◽  
Hexane Extraction ◽  
Higher Plant ◽  
Major Site ◽  
Haem Biosynthesis

Ferrochelatase is the terminal enzyme of haem biosynthesis, catalysing the insertion of ferrous iron into the macrocycle of protoporphyrin IX, the last common intermediate of haem and chlorophyll synthesis. Its activity has been reported in both plastids and mitochondria of higher plants, but the relative amounts of the enzyme in the two organelles are unknown. Ferrochelatase is difficult to assay since ferrous iron requires strict anaerobic conditions to prevent oxidation, and in photosynthetic tissues chlorophyll interferes with the quantification of the product. Accordingly, we developed a sensitive fluorimetric assay for ferrochelatase that employs Co2+ and deuteroporphyrin in place of the natural substrates, and measures the decrease in deuteroporphyrin fluorescence. A hexane-extraction step to remove chlorophyll is included for green tissue. The assay is linear over a range of chloroplast protein concentrations, with an average specific activity of 0.68nmol·min−1·mg of protein−1, the highest yet reported. The corresponding value for mitochondria is 0.19nmol·min−1·mg of protein−1. The enzyme is inhibited by N-methylprotoporphyrin, with an estimated IC50 value of ≈ 1nM. Using this assay we have quantified ferrochelatase activity in plastids and mitochondria from green pea leaves, etiolated pea leaves and pea roots to determine the relative amounts in the two organelles. We found that, in all three tissues, greater than 90% of the activity was associated with plastids, but ferrochelatase was reproducibly detected in mitochondria, at levels greater than the contaminating plastid marker enzyme, and was latent. Our results indicate that plastids are the major site of haem biosynthesis in higher plant cells, but that mitochondria also have the capacity for haem production.

scholarly journals Electronic Structure of Tyrosyl D Radical of Photosystem II, as Revealed by 2D-Hyperfine Sublevel Correlation Spectroscopy

2021 ◽  
Vol 7 (9) ◽  
pp. 131
Author(s):  
Maria Chrysina ◽  
Georgia Zahariou ◽  
Nikolaos Ioannidis ◽  
Yiannis Sanakis ◽  
George Mitrikas
Keyword(s):  
Electronic Structure ◽  
Photosystem Ii ◽  
Water Oxidation ◽  
Spinacia Oleracea ◽  
Higher Plants ◽  
Correlation Spectroscopy ◽  
Oxygen Evolving Complex ◽  
Higher Plant ◽  
Proton Coupled Electron Transfer ◽  
S Oxidation

The biological water oxidation takes place in Photosystem II (PSII), a multi-subunit protein located in thylakoid membranes of higher plant chloroplasts and cyanobacteria. The catalytic site of PSII is a Mn4Ca cluster and is known as the oxygen evolving complex (OEC) of PSII. Two tyrosine residues D1-Tyr161 (YZ) and D2-Tyr160 (YD) are symmetrically placed in the two core subunits D1 and D2 and participate in proton coupled electron transfer reactions. YZ of PSII is near the OEC and mediates electron coupled proton transfer from Mn4Ca to the photooxidizable chlorophyll species P680+. YD does not directly interact with OEC, but is crucial for modulating the various S oxidation states of the OEC. In PSII from higher plants the environment of YD• radical has been extensively characterized only in spinach (Spinacia oleracea) Mn- depleted non functional PSII membranes. Here, we present a 2D-HYSCORE investigation in functional PSII of spinach to determine the electronic structure of YD• radical. The hyperfine couplings of the protons that interact with the YD• radical are determined and the relevant assignment is provided. A discussion on the similarities and differences between the present results and the results from studies performed in non functional PSII membranes from higher plants and PSII preparations from other organisms is given.

scholarly journals Genetic fine-structure of the GA-1 locus in the higher plant Arabidopsis thaliana (L.) Heynh

1983 ◽  
Vol 41 (1) ◽  
pp. 57-68 ◽  
Author(s):  
M. Koornneef ◽  
J. Van Eden ◽  
C. J. Hanhart ◽  
A. M. M. De Jongh
Keyword(s):  
Arabidopsis Thaliana ◽  
Fine Structure ◽  
Higher Plants ◽  
Wild Type ◽  
Higher Plant ◽  
Selfed Progeny ◽  
Intragenic Deletion ◽  
Genetic Length ◽  
Genetic Fine Structure ◽  
Half Diallel

SUMMARYNon-germinating gibberellin (GA) responsive mutants are a powerful tool to study genetic fine structure in higher plants. Nine alleles (EMS-and fast neutron-induced) of the ga-1 locus of Arabidopsis thaliana were tested in a complete half-diallel. No wild type ‘recombinants’ were found in the selfed progeny of 9 homoallelic combinations (in total 3 × 105 plants); in the progenies from the 36 selfed hetero allelics the wild type frequency ranged from zero to 6·6 × 10−4. These frequencies allowed the construction of an internally consistent map for five different sites representing eight alleles. The ninth allele covered three sites and thus behaved like an intragenic deletion. The estimate of the total genetic length of the ga-1 locus was 0·07 cM. The order of the sites was also clearly reflected by the association with proximal outside markers. On the assumption that wild type gametes predominantly arise from reciprocal events, it was shown that a cross-over within the ga-1 locus leads to positive interference in the adjacent region.The results are discussed with respect to the mutagen used, the frequencies found in other plant and Drosophila genes, and the possible occurrence of gene conversion.

A Relationship between Market Share Elasticities and Brand Switching Probabilities

1998 ◽  
Vol 35 (1) ◽  
pp. 99-113 ◽  
Author(s):  
Randolph E. Bucklin ◽  
Gary J. Russell ◽  
V. Srinivasan
Keyword(s):  
Market Share ◽  
Logit Model ◽  
Laundry Detergent ◽  
Brand Switching ◽  
Switching Matrix ◽  
Scanner Panel Data ◽  
Liquid Laundry Detergent ◽  
Heterogeneous Consumers ◽  
Scanner Panel ◽  
The Relationship

The authors derive a theoretical relationship between the aggregate market share elasticity matrix and the aggregate brand switching matrix on the basis of a logit model of heterogeneous consumers choosing among competing brands in a product class. Aggregate cross-elasticities are shown to be proportional (through a single scaling constant) to their corresponding aggregate row-conditional brand switching probabilities. Aggregate own-elasticities are shown to be proportional (through the negative of the same scaling constant) to one minus their corresponding aggregate row-conditional repeat purchase probabilities. An empirical analysis conducted on household scanner panel data in the liquid laundry detergent category shows that the theoretical correspondence holds as a very good approximation. An illustrative use of the relationship in estimating aggregate (store-level) models of market share indicates that the relationship helps improve predictive validity in a holdout period.

Brand Choice, Purchase Incidence, and Segmentation: An Integrated Modeling Approach

1992 ◽  
Vol 29 (2) ◽  
pp. 201-215 ◽  
Author(s):  
Randolph E. Bucklin ◽  
Sunil Gupta
Keyword(s):  
Market Segmentation ◽  
Laundry Detergent ◽  
Brand Choice ◽  
Purchase Behavior ◽  
Brand Preference ◽  
Purchase Incidence ◽  
Scanner Panel Data ◽  
Liquid Laundry Detergent ◽  
Marketing Variables ◽  
Scanner Panel

The authors develop an approach to market segmentation based on consumer response to marketing variables in both brand choice and category purchase incidence. The approach reveals segmentation as well as the nature of choice and incidence response for each segment. Brand choice and purchase incidence decisions are modeled at the segment level with the disaggregate multinomial logit and nested logit models; segment sizes are estimated simultaneously with the choice and incidence probabilities. Households are assigned to segments by using their posterior probabilities of segment membership based on their purchase histories. The procedure thereby permits an analysis of the demographic, purchase behavior, and brand preference characteristics of each response segment. The authors illustrate their approach with scanner panel data on the liquid laundry detergent category and find segmentation in price and promotion sensitivity for both brand choice and category purchase incidence. The results suggest that many households that switch brands on the basis of price and promotion do not also accelerate their category purchases and that households that accelerate purchases do not necessarily switch brands.

The higher plant PII signal transduction protein: structure, function and properties

2007 ◽  
Vol 85 (6) ◽  
pp. 533-537 ◽  
Author(s):  
Greg B.G. Moorhead ◽  
Tony S. Ferrar ◽  
Yan M. Chen ◽  
Yutaka Mizuno ◽  
Catherine S. Smith ◽  
...  
Keyword(s):  
Higher Plants ◽  
Structural Features ◽  
Signaling Proteins ◽  
Higher Plant ◽  
Binding Partner ◽  
Signal Transduction Protein ◽  
Metabolic Sensor ◽  
Nitrogen Sensing ◽  
Over 40 Years

The PII carbon/nitrogen sensing protein was discovered in Escherichia coli (Migula 1895) Castellani and Chalmers 1919, over 40 years ago. Orthologues have been discovered in three kingdoms of life making it one of the most ancient and conserved signaling proteins known. Recent advances in the field have established its primary binding partner in plants as N-acetyl glutamate kinase and the crystal structure has revealed features unique to plants that likely contribute to its function in vivo. Here, we review the properties, function, and novel structural features of this chloroplast-localized metabolic sensor of higher plants.

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