Coal-smoke pollution modifies physio-chemical characteristics of tissues during the ontogeny of Peristrophe bicalyculata

Biologia ◽  
2008 ◽  
Vol 63 (6) ◽  
Author(s):  
Farah Nighat ◽  
Mahmooduzzafar ◽  
Muhammad Iqbal

AbstractCoal-smoke emissions of a thermal power plant affected the physio-chemical status of Peristrophe bicalyculata (Reth) Nees, as observed at the pre-flowering, flowering and post-flowering stages of plant growth. The nitrate level was raised while nitrate reductase activity, and the soluble protein content of leaf declined heavily at the polluted site during different stages of plant growth, compared to the control. The rate of photosynthesis also decreased under the pollution stress. Sugar level in root, stem and leaves increased with growing age of the plant but was always lower at the polluted site than at the reference site. In roots, the difference was marginal till flowering stage and quite conspicuous afterwards; stems showed a reverse pattern of variation. Sulphur content was higher at the polluted site in all the organs and at each stage of the plant life. The Zn and Fe concentrations were reduced in all plant parts under the pollution stress. Copper content in root was consistently low at the polluted site. In the stem and leaves, however, it was almost equal on both the sites at the pre-flowering stage but showed a wide difference during the later part of plant ontogeny.

2017 ◽  
Vol 37 (332) ◽  
pp. 29-37 ◽  
Author(s):  
Ilze Skudra ◽  
Antons Ruza

Abstract Nitrogen management strategy in plant growth period based on chlorophyll content evaluation in plant can improve nitrogen usage efficiency and reduce environmental contamination. This study is aimed to determine the impact of different nitrogen and sulphur fertilizer rates on dynamics of chlorophyll content in winter wheat during vegetative growth and to determine the relationship between nitrogen and chlorophyll content and grain yield of winter wheat. Field trial involving a winter wheat (Triticum aestivum L.) variety ‘Kranich’ was conducted at the LUA Research and Study Farm Vecauce during a three-year period (2012-2015). The treatments were 0, 85, 153, 175+S21, 175 (in 2015), 187 N kg ha−1 and different nitrogen norms according to chlorophyll meter Yara N-tester (Konica Minolta Ltd.) data: 180, 150, 205 N kg ha−1 depending on the year. The results of the trial show that the maximum chlorophyll content in different plant parts was observed at the end of flowering stage. The chlorophyll content depended on the level of mineral fertilisation. The highest chlorophyll content in leaves, stems and ears was obtained by using additional sulphur in two trial years. Usage of chlorophyll meter Yara N-tester obtained the highest chlorophyll content in all analyzed plant parts in one trial year. Chlorophyll content was significantly dependant on plant growth stage in stems in all trial years, in leaves in two trial years, and in ears in one year. Nitrogen fertilization significantly affected chlorophyll content in leaves and stems in one trial year. Close positive correlation was observed between grain yield and wheat plant chlorophyll content and average nitrogen concentration at the end of flowering stage in all three trial years.


HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 474d-474
Author(s):  
N.K. Damayanthi Ranwala ◽  
Dennis R. Decoteau

This study was conducted to evaluate the spectral properties of various colored plastic color mulches and to determine the effects of upwardly reflected light from the mulch surfaces on watermelon plant growth when differences in root zone temperatures are minimized. Two-week-old watermelon plants were grown with black mulch, red-painted mulch, SRM-Red mulch (Sonoco, Inc., Harstville, S.C.), and white mulch. Total light reflection (58 μmol·m–2·s–1 in 400–700 nm) and red: far-red (R:FR = 0.44) of reflected light were lower in black mulch and highest in white mulch (634 and 0.92, respectively). Both black mulch and white mulch had same blue:red (B:R = 0.6) while white mulch had higher B:FR (0.58) in reflected light compared to black mulch (0.26). Reflective properties of red mulches were somewhat similar, and R:FR, B:R, and B:FR were 0.8, 0.2, and 0.18, respectively. However, SRM-Red mulch had highest total light (355 μmol·m–2·s–1 in 400–700 nm) transmission through the mulch, and R:FR, B:R, and B:FR were 0.84, 0.28, and 0.23, respectively. Light transmission through the other mulches was nonsignificant. Watermelon plants grown with black mulch and red mulches had higher internode lengths compared to white mulch after 20 days. Further, plants grown under black had significant higher petiole elongation accompanied with higher dry mass partitioning to petioles, and lower partitioning to roots, stems, and leaves. There was no effects of surface mulch color on total plant dry mass or photosynthesis although plants with black had higher transpiration rate. This suggests the differential regulation of dry mass partitioning among plant parts due to mulch color. The similar plant responses with black mulch and white mulch to plants treated with FR or R light at the end of photoperiod implies the involvement of phytochrome regulation of growth due to mulch surface color.


1998 ◽  
Vol 17 (5) ◽  
pp. 272-277 ◽  
Author(s):  
D J Morré

A number of solvents including ethyl, amyl, butyl, octyl and benzyl alcohols, ethylene glycol, ethyl acetate, acetone, diethyl ether, propylene oxide, r-dioxane, benzene, xylene, chloroform and carbon tetrachloride stimulate the growth of plants or plant parts at low concentrations and inhibit at high concentrations. These same solvents, at low dilutions, stimulate the activity of a growth-related protein disulfide-thiol interchange protein (TIP) with NADH: protein disulfide reductase (NADH oxidase) (NOX) activity with plasma membrane vesicles isolated from elongating regions cut from dark grown seedlings of soybeans. Based on these and other findings, we suggest the TIP/NOX protein to be the molecular target of the biological effects of low levels of exposure (hormesis) involved in the stimulation of plant growth.


2020 ◽  
Vol 19 ◽  
pp. 11
Author(s):  
LORENA GABRIELA ALMEIDA ◽  
EDER MARCOS DA SILVA ◽  
PAULO CÉSAR MAGALHÃES ◽  
DÉCIO KARAM ◽  
CAROLINE OLIVEIRA DOS REIS ◽  
...  

Low water availability is characterized as an abiotic stressthat limits the agricultural production. Due to the physical and chemicalcharacteristics of the chitosan (CHT), this substance might stimulatephysiological responses on plants to tolerate the water deficit. In this sense,we submitted corn plants to water deficit and application of chitosan on theleaves (140 mg/L) during pre flowering stage. It were analyzed two cornhybrids genotypes contrasting for water deficit tolerance: DKB 390 (tolerant)and BRS1010 (sensitive). Then, we performed evaluations on the rootsystem and production components. Corn plants submitted to the applicationof chitosan presented a specific behavior: when compared the hybrids,the tolerant one presented a root system that was more developed and anexpressive agronomical yield. These results highlight the fact that the chitosanstimulates plant growth, enhancing their root system and contributing toincrease the availability and absorption of water and nutrients. The chitosanpresents a potential to reduce the negative effects of water deficit on the rootsystems, without compromising the agronomical yield.


10.30544/340 ◽  
2018 ◽  
Vol 24 (2) ◽  
pp. 123-132
Author(s):  
Bore V. Jegdic ◽  
Bojana M. Radojković ◽  
Biljana M. Bobić ◽  
Marija M. Krmar ◽  
Slavica Ristić

Corrosion behavior of metalized layers, obtained by Plasma Transferred Arc (PTA) process and by High-Velocity Oxygen Fuel (HVOF) process with the purpose to improve the wear resistance of vital parts of ventilation mill in a thermal power plant, has been tested. The test is performed using three electrochemical techniques, in a solution containing chloride and sulfate ions. It is shown that the steel surface (base metal) dissolves uniformly, without pitting or other forms of local dissolution. Morphology of metalized layers surface indicates that dissolution is non-uniform, but it still can be considered as general corrosion. The corrosion rate of base metal and metalized layer obtained by PTA process is rather low, while the corrosion rate of the metalized layer obtained by HVOF process is much higher. Also, the difference in corrosion potentials between the base metal and the HVOF layer is pretty high but slightly less than maximum allowed difference (prescribed by the standard), to avoid excessive galvanic corrosion. The values of corrosion rate obtained by different electrochemical techniques are in excellent agreement.


2018 ◽  
Vol 45 (3) ◽  
pp. 278 ◽  
Author(s):  
Firmansyah Aznur ◽  
Suwarto , ◽  
Dan Heni Purnamawati

Light use efficiency (LUE) determines biomass production based on interception energy during photosynthesis. The product of photosynthesis is allocated to the plants organs based on the partitioning of carbohydrates. The LUE and carbohydrate partitioning are two important parameters in crop modelling. The research was conducted at Cikabayan experimental station of IPB, Bogor from July to November 2015. The experiment was designed according to a randomize block design with five replications. The fertilizer treatments rate were 0%, 50%, 100%, 150%, and 200% of reference N fertilization of 120 kg ha-1.  The  value  of  light use efficiency and the partition coefficient of sorghum were not affected by N fertilization. The value of light use efficiency is 1.41 g MJ-1. The carbohydrates partitioning was developed based on plant growth stage. The partition from the planting to the emergence stage (0 ≤ s ≤ 0.25) was 0.81 x s/0.25 root, 0 stem, 0.19 x s/0.25 leaves, and 0 panicle. The partition from the emergence to the maximum vegetative stage (0.25 &lt; s ≤ 0.5) was 0.81-(0.59 x s/0.5) root, 0.14 x s/0.5  stem, 0.19 + (0.45 x s/0.5) leaves, and 0 panicle. The partition from the maximum vegetative stage to the flowering stage (0.5 &lt; s ≤ 0.75) was 0.22 - (0.09 x s/0.75) root, 0.14 + (0.39 x s/0.75) stem, 0.64 - (0.46 x s/0.75) leaves, and 0.16 x s/0.75 panicle. The partition from flowering to the harvest stage (0.75 &lt; s ≤ 1) was 0.13 - (0.13 x s) root, 0.53 - (0.52 x s) stem, 0.18-(0.18 x s) leaves, and 0.16 + (0.84 x s) panicle.<br /><br />Keywords: crop modelling, light use efficiency, N fertilizer, partitioning carbohydrates<br /><br />


2020 ◽  
Vol 10 (14) ◽  
pp. 4883
Author(s):  
Junji Sakamoto ◽  
Naoya Tada ◽  
Takeshi Uemori ◽  
Hayato Kuniyasu

Turbine blades for thermal power plants are exposed to severe environments, making it necessary to ensure safety against damage, such as crack formation. A previous method detected internal cracks by applying a small load to a target member. Changes in the surface properties of the material were detected before and after the load using a digital holographic microscope and a digital height correlation method. In this study, this technique was applied in combination with finite element analysis using a 2D and 3D model simulating the turbine blades. Analysis clarified that the change in the surface properties under a small load varied according to the presence or absence of a crack, and elucidated the strain distribution that caused the difference in the change. In addition, analyses of the 2D model considering the material anisotropy and thermal barrier coating were conducted. The difference in the change in the surface properties and strain distribution according to the presence or absence of cracks was elucidated. The difference in the change in the top surface height distribution of the materials with and without a crack was directly proportional to the crack length. As the value was large with respect to the vertical resolution of 0.2 nm of the digital holographic microscope, the change could be detected by the microscope.


Agronomy ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 204 ◽  
Author(s):  
Anabel Saran ◽  
Valeria Imperato ◽  
Lucia Fernandez ◽  
Panos Gkorezis ◽  
Jan d’Haen ◽  
...  

Lead (Pb) and cadmium (Cd) are major environmental pollutants, and the accumulation of these elements in soils and plants is of great concern in agricultural production due to their toxic effects on crop growth. Also, these elements can enter into the food chain and severely affect human and animal health. Bioaugmentation with plant growth-promoting bacteria (PGPB) can contribute to an environmentally friendly and effective remediation approach by improving plant survival and promoting element phytostabilization or extraction under such harsh conditions. We isolated and characterised Pb and Cd-tolerant root-associated bacteria from Helianthus petiolaris growing on a Pb/Cd polluted soil in order to compose inoculants that can promote plant growth and also ameliorate the phytostabilization or phytoextraction efficiency. One hundred and five trace element-tolerant rhizospheric and endophytic bacterial strains belonging to eight different genera were isolated from the aromatic plant species Helianthus petiolaris. Most of the strains showed multiple PGP-capabilities, ability to immobilise trace elements on their cell wall, and promotion of seed germination. Bacillus paramycoides ST9, Bacillus wiedmannii ST29, Bacillus proteolyticus ST89, Brevibacterium frigoritolerans ST30, Cellulosimicrobium cellulans ST54 and Methylobacterium sp. ST85 were selected to perform bioaugmentation assays in greenhouse microcosms. After 2 months, seedlings of sunflower (H. annuus) grown on polluted soil and inoculated with B. proteolyticus ST89 produced 40% more biomass compared to the non-inoculated control plants and accumulated 20 % less Pb and 40% less Cd in the aboveground plant parts. In contrast, B. paramycoides ST9 increased the bioaccumulation factor (BAF) of Pb three times and of Cd six times without inhibiting plant growth. Our results indicate that, depending on the strain, bioaugmentation with specific beneficial bacteria can improve plant growth and either reduce trace element mobility or enhance plant trace element uptake.


1934 ◽  
Vol 11 (5) ◽  
pp. 582-588 ◽  
Author(s):  
T. Johnson ◽  
O. Johnson

In Part I of these studies it has been shown that the rapidly growing tissues of the wheat plant are more susceptible to stem rust than the older tissues. An attempt was made to discover if a physiological or chemical basis could be found for the difference in reaction of the young and older tissues.Analyses were made to determine the sugar content of young (susceptible) and older (resistant) tissues of four wheat varieties resistant in the adult stage and of the corresponding plant parts of three wheat varieties which in the adult stage showed little or no resistance to rust. The young tissues comprised the young leaves still enfolded by the uppermost sheaths and the young stems below the uppermost node; the older tissues were represented by the fully developed upper leaves and their adherent sheaths. The analyses showed a considerably higher content of sugars in the young than in the older tissues of the seven varieties tested. The difference was particularly great in the content of reducing sugars but rather slight in the disaccharide content (expressed as invert sugar). However, as all the varieties, irrespective of resistance or susceptibility to rust in the adult stage, showed much the same difference in the sugar content of their young and older tissues, it does not seem likely that there is any direct relation between sugar content and reaction to rust.


Agronomy ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 266 ◽  
Author(s):  
Shumaila Khan ◽  
Hongjun Yu ◽  
Qiang Li ◽  
Yinan Gao ◽  
Basheer Noman Sallam ◽  
...  

As natural plant growth stimulators, amino acids are widely used to improve the yield and quality of crops. Several studies have illustrated the effects of different amino acids on lettuce plant parts. However, the effects of applying single amino acids on root growth remain elusive. The objective of this study was to evaluate the effect of root application of L-methionine on the growth of lettuce. In this study, two successive experiments on butterhead lettuce were conducted under hydroponic conditions. Three amino acids, L-methionine (20 mg/L), L-glycine (210 mg/L), and L-tryptophan (220 mg/L), were applied separately. L-methionine significantly increased the growth performance by 23.60%, whereas growth using L-tryptophan and L-glycine decreased by 98.78% and 27.45%, respectively. Considering the results of the first experiment, a second experiment was established with different concentrations of L-methionine (2200 mg/L, 220 mg/L, 22 mg/L, 2.2 mg/L, 0.2 mg/L, and 0.02 mg/L). The plants were allowed to grow for four weeks. Leaf width, plant area, leaf area, chlorophyll contents, etc., were evaluated. The results show that plant growth significantly improved by applying L-methionine at the lowest concentrations of 0.2 mg/L and 0.02 mg/L, which can, therefore, improve hydroponic production of lettuce and, accordingly, human nutrition.


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