Effects Of Ozone Stress Research Articles

Effects of Ozone Stress on Rhizosphere Soil of Poplar Seedlings

Near-surface O3 has negative effects on plant productivity; however there were few studies on the effects of O3 pollution on the belowground part of the ecosystem. The effect of O3 stress on the belowground parts of poplar is unclear. We investigated the effects of O3 pollution on poplar rhizosphere soil in open-top chambers (OTC). Two kinds of plants with different O3 sensitivity were selected, i.e., high-sensitive poplar clone 546 and low-sensitive poplar clone 107. The control group and high-concentration O3 group were set up: charcoal-filtered air, CF; unfiltered air + 60 ppb O3, NF. Poplar rhizosphere soil was taken after 96 days (15 June to 17 September 2020) of cultivation in OTCs. O3 stress decreased the amplicon sequence variations (ASVs) of microorganisms in poplar 107 and poplar 546 rhizosphere soil, with no significant interspecific difference. The effect of O3 fumigation on the fungal community was greater than that on the bacterial community. The correlation between the bacterial community and rhizosphere soil physicochemical indices was closer than that of the fungal community. Some fungi, such as Clitopilus hobsonii, Mortierella sp., and Minimedusa, might help poplar resist the O3 stress. O3 stress had direct impacts on the pH, nutrients, and enzyme activities of rhizosphere soil, while it had indirect negative impacts on microbial community composition by nutrients. There was no difference in sensitivity between rhizosphere soil response to O3 stress of poplar clone 107 and clone 546, which might take a longer accumulation time to show the effect. This study provides a certain basis for accurately evaluating the ecological effects of O3 pollution.

Impacts of ozone stress on stem lodging characteristics of different indica and japonica rice cultivars

AbstractOzone (O3) stress inhibits rice growth and development, resulting in yield loss and poor quality. However, the effect of ozone stress on the lodging resistance of rice stems has scarcely been reported. In this study, three indica rice cultivars and three modern japonica rice cultivars were treated with high O3 concentration (100 ppb) while a gas fumigation platform was used in the indoor control (about 10 ppb). The influence of O3 stress on lodging resistance was investigated in 2016 and 2017. Ozone stress reduced the in situ pushing resistance of intact plants by 40% and single stems by 32.0%. The breaking resistance of the third, fourth, and fifth internodes from the top of the rice stem was, respectively, reduced by 24.0%, 25.1%, and 33.6%, on average. The O3‐induced reduction in the basal internode morphological characteristics was associated with the reduced cross‐sectional area, maximum and minimum stem diameter, dry weight per unit length, length, dry weight, and culm wall thickness. Among these characteristics, the largest reduction was exhibited by internode dry weight (−43.1%), while the lowest reduction was observed for culm wall thickness (−9.7%). The O3 induced a significantly higher reduction in basal internode characteristics of indica compared with the japonica rice, with a larger effect in the lower internode than the upper internode, indicating a significant interaction between O3 and rice cultivar and internode position. Statistical analysis revealed a significant positive linear correlation between the response of in situ pushing resistance of rice under O3 stress and the response of basal internode breaking resistance, cross‐sectional area, and dry weight per unit length. Ozone stress significantly reduced the lodging resistance in the rice stem, which is primarily associated with the thinning and poor filling of the basal internodes, and the O3 impacts varied with cultivars and internode positions, but were similar between the two years. These results provide a scientific reference for the study of lodging resistance regulation of rice under high O3 concentrations.

Effects of Ozone Stress on Stem Lodging Resistance of Different Rice Cultivars

Effects of Ozone Stress on Stem Lodging Resistance of Different Rice Cultivars

Effect of ozone stress on yield characteristics of indica-japonica hybrid rice Yongyou 538 in two consecutive growing seasons

The hybrid rice cultivar Yongyou 538 (Y538) was exposed to 100 ppb ozone (O3) and control conditions throughout the cropping seasons in 2016–2017 in Yangzhou, China. The average daily maximum temperature during reproductive the growth stage (mid-August) of Y538 in 2016 was 3.6 °C higher than that in 2017. The heading stage of Y538 was reached 6.5 days earlier in the control than in the high-O3 treatments. Ozone stress decreased plant height and tiller number at all growth stages, and the O3–induced reductions in these two parameters were gradually increased with plant development. Compared to the control, O3 stress significantly decreased yield by an average of 29.9 %, and by 35.2 and 24.0 % in 2016 and 2017, respectively. Averaged across 2 years, O3 stress caused slight reductions in both panicle number (PN) and filled grain weight (FGW). However, spikelet number per panicle (-9.6 %, SNP) and filled grain percentage (-17.5 %, FGP) showed significant reductions due to O3 exposure, while O3 stress increased empty grain percentage (EGP) and incompletely-filled grain percentage (IGP) by 72.9 and 80.0 %, respectively, when averaged across 2 years. A significant interaction of O3 by year or grain position in a panicle was observed on yield, FGP, EGP, and IGP, as the changes in 2016 were more significantly affected than those in 2017; grains at lower parts of the panicle were more affected than those at upper parts. Ozone stress significantly reduced the above ground dry weight of rice at maturity in 2 years by an average of 18.3 %, which was mainly related to the decrease in stem (-19.3 %) and panicle weight (-22.9 %), while no O3 effect was detected for leaf weight. Ozone stress significantly increased the ratio of leaf to aboveground dry weight by 23.4 % when averaged across 2 years, while the ratio of stem or panicle showed a declining trend. Correlation and path analysis showed that yield loss due to O3 exposure was closely related to the decreases in FGP (especially the middle and lower parts of the panicle) and SNP. Ozone treatment of 100 ppb significantly decreased the productivity of Y538, and the high temperature in the reproductive growth period would further exacerbate the damage caused by O3, leading to substantial yield losses.

Effects of ozone stress on flowering phenology, plant-pollinator interactions and plant reproductive success.

Tropospheric ozone is a highly oxidative pollutant with the potential to alter plant metabolism. The direct effects of ozone on plant phenotype may alter interactions with other organisms, such as pollinators, and, consequently, affect plant reproductive success. In a set of greenhouse experiments, we tested whether exposure of plants to a high level of ozone affected their phenological development, their attractiveness to four different pollinators (mason bees, honeybees, hoverflies and bumblebees) and, ultimately, their reproductive success. Exposure of plants to ozone accelerated flowering, particularly on plants that were growing in autumn, when light and temperature cues, that commonly promote flowering, were weaker. Simultaneously, there was a tendency for ozone-exposed plants to disinvest in vegetative growth. Plant exposure to ozone did not substantially affect pollinator preference, but bumblebees had a tendency to visit more flowers on ozone-exposed plants, an effect that was driven by the fact that these plants tended to have more open flowers, meaning a stronger attraction signal. Honeybees spent more time per flower on ozone-exposed plants than on control plants. Acceleration of flower production and the behavioural responses of pollinators to ozone-exposed plants resulted in retained reproductive fitness of plants pollinated by bumblebees, honeybees and mason bees, despite the negative effects of ozone on plant growth. Plants that were pollinated by hoverflies had a reduction in reproductive fitness in response to ozone. In a natural setting, acceleration of flowering by ozone might foster desynchronization between plant and pollinator activities. This can have a strong impact on plants with short flowering periods and on plants that, unlike wild mustard, lack compensatory mechanisms to cope with the absence of pollinator activity in the beginning of flowering.

Effect of ozone stress on the intracellular metabolites from Cobetia marina

A GCxGC-MS system was employed with a non-polar × mid-polar column set for the metabolic non-target analysis of Cobetia marina, the model bacteria for marine biofouling. C. marina was treated with ozone to investigate the intracellular metabolic state change under oxidative stress. A minimal inhibitory concentration test was involved to guarantee that the applied ozone dosages were not lethal for the cells. In this study, non-target analyses were performed to identify the metabolites according to the NIST database. As a result, over 170 signals were detected under normal living conditions including 35 potential metabolites. By the comparison of ozone-treated and non-treated samples, five compounds were selected to describe observed trends of signals in the contour plots. Oleic acid exhibited a slight growth by increasing ozone dosage. In contrast, other metabolites such as the amino acid l-proline showed less abundance after ozone treatment, which was more evident once ozone dosage was raised. Thus, this work could provide a hint for searching for up/downregulating factors in such environmental stress conditions for C. marina.Graphical abstract

Effects of ozone stress on amylose content and starch RVA profile in grains located at diffe-rent positions on a panicle

The increase of ground-level ozone concentration significantly reduces rice yield, but its effect on grain quality in association with the positions on a panicle was largely unknown. The effects of ozone stress on amylose content and RVA profile of rice grains located at different positions of panicles were studied by using a sunlit gas fumigation platform. Eight varieties representing different types of rice were fumigated under ambient (9 nL·L-1) or elevated ozone (100 nL·L-1) concentrations from transplanting until maturity. The results showed that elevated ozone treatment significantly reduced amylose content, maximum viscosity, hot viscosity, breakdown and cold viscosity by 5.9%, 7.6%, 5.9%, 11.6%, 2.9%, respectively, but increased the setback and gelatinization temperature by 24.9% and 1.0%. There were significant differences among varieties for amylose content and all parameters in RVA profile. The grains located at different positions on a panicle differed in amylose content, maximum viscosity, hot viscosity, breakdown and cold viscosity. The superior grains located at the upper part of a panicle had the highest value and the inferior grains located at the lower part of a panicle had the lowest value. However, the setback in RVA profile showed a different trend, with the superior grains having the lowest setback but inferior grains having the highest setback. In most cases, there were significant interactive effects of ozone by year or ozone by variety on amylose content and RVA profile. No significant ozone by grain position interaction on RVA profile was found, although the responses of superior grains to ozone stress was slightly smaller than those of inferior grains or grains located at the middle part of a panicle. The results demonstrated that ozone fumigation of 100 nL·L-1 during rice growing season deteriorated rice quality, with the magnitude of deterioration varying with growth seasons and varieties and little impacts of grain positions on a panicle.

Effect of ozone stress on the absorption, distribution, and utilization of nitrogen in rice under different planting densities

High ozone (O3) can cause great damage to plants. However, the effect of high O3 on nitrogen (N) absorption, distribution, and utilization in rice at different growth stages under different planting densities is poorly understood. In the present study, a conventional cultivar (Yangdao 6) and a hybrid cultivar (II You 084) with different planting densities were exposed to an elevated amount of O3 (E-O3; 50% higher than that of the control, C-O3) under a free-air gas concentration enrichment (FACE) system. N absorption, distribution, and utilization of the green leaves, stems, and shoots at tillering, jointing heading, and maturity were investigated. Results showed that E-O3 significantly increased the N content in the shoots of Yangdao 6 by 7.5%, 12.7%, and 19.6%, respectively, at jointing, heading, and maturity. Also, the N content in the shoots of II You 084 increased by 5.4%, 6.5%, and 8.4% at the corresponding growth stage upon E-O3 application. E-O3 significantly decreased N accumulation of II You 084 by 8.3%, 4.9%, 4.7%, and 19.2%, respectively, at tillering, jointing, heading, and maturity. Further, E-O3 had a decreasing effect on the N distribution in green leaves (p ≤ 0.05) of both cultivars, but exerted an increasing effect on that in the stems of both cultivars (p ≤ 0.05). In addition, E-O3 significantly decreased the N use efficiency (NUE) for biomass of the two cultivars in all growth stages. These results revealed that E-O3 could increase the N content in rice plants but decrease the N accumulation and utilization in both cultivars. The effects of E-O3 on N absorption, distribution, and utilization were not affected by planting density.

臭氧胁迫对植物主要生理功能的影响

Nowadays,with the increase of ozone precursor caused by photochemical reactions,the extent of global plants suffering from ozone stress in the troposphere is getting more and more serious. Ozone pollution has been considered to be the primary cause of forest decline and tree dieback in Eastern and Western Europe and throughout the United States. Ozone stress could have strong impacts on the utilization of light and the production of photosynthesis products in plants,and lead to the decline of photosynthetic rate through stomatal limitation and non-stomatal limitation. The effects of ozone on plants are closely related to the accumulation of metabolic substance in plants. Various defensive protection mechanisms are initiated by ozone stress,such as antioxidant system and membrane system. Ozone stress has changed the absorption of carbon and mineral nutrients in plants and caused their redistribution. And it could also induce deep changes in gene expression. In order to adapt to the environment with ozone stress,plants adjust their physiological and biochemical mechanism to ensure their vital movement. For example,the content of permeable mass would be regulated by cell to maintain osmotic potential balance,meanwhile the metabolic pathway would be changed to keep energy reserves and reduce metabolic rate in plants. And all kinds of antioxidant enzymes' activity in the cell would increase to clear up free radicals and mitigate or even avoid cell damages. It' s clear that the ecological environment has important effects on biological evolution. And it's confirmed by the plants' physiological effects from ozone stress,which is also another kind of evidence of biological evolutionism. In this paper,the impacts that ozone does to plants' photosynthetic physiology,respiratory metabolism,antioxidant system,membrane system,nutrients absorption and allocation,and molecular physiology were summarized to get a more comprehensive understanding of the physiological and biochemical mechanism of plants adapting to ozone stress. Hotspots for future ozone researches should be focused on the enhancement of effects of ozone stress on plant physiology in individual and community level,the gene regulation and related mechanism of signal transmission network system of plants under ozone stress,plants breeding to adapt to the environment with ozone stress by methods such as molecular marker,gene mapping,genomics approach and transgenic technology,research condition that should be close to natural environment as much as possible,the effects of ozone stress on major physiological functions of subtropical and tropical forests,and the models to assess the impacts of ozone on plants.

Coupled model identifies effect of ozone stress on vegetative growth

An intricate feedback system ties together the activity of vegetation and tropospheric ozone. Ground level ozone, drawn from the atmosphere through dry deposition, stresses plants, inhibiting their growth. Plants, in turn, release biogenic volatile organic compounds (VOCs), chemicals that can either enhance or inhibit the deposition of ozone depending on the availability of another class of chemicals, nitrous oxides. Adding to important vegetative processes such as photosynthesis or evapotranspiration, biogenic aerosols can also increase or decrease ozone formation by modulating heat waves. Therefore, understanding the bidirectional interaction between ozone and vegetative growth is important for accurately representing the climate.

Growth of Adult Norway Spruce (Picea abies [L.] Karst.) and European Beech (Fagus sylvatica L.) Under Free-Air Ozone Fumigation

This study attempted to detect the impact of ozone on adult trees of Norway spruce ( Picea abies [L.] Karst.) and European beech ( Fagus sylvatica L.) in an experimental mixed stand in Southern Bavaria, Germany. The aim was to examine whether there is a decrease in growth when trees are exposed to higher than atmospheric concentrations of ozone. This exposure was put into effect using a free-air fumigation system at tree crown level. Growth analysis was carried out on a group of 47 spruce and 36 beech trees, where radial stem increment at breast height - a sensitive index for stress - was measured. The ozone monitoring system allowed values to be obtained for the accumulated ozone exposure (SUM00) of each individual tree, so that their radial increment over three years could be correlated with the corresponding ozone exposure for the same time period. Correlation and regression analysis were then carried out to test the influence of ozone on diameter increment. In both spruce and beech, the initial stem diameter was the most influential factor on radial increment in the following year. A linear model was applied, including the diameter of the preceding year and the ozone exposure of the current year as predicting factors. For spruce trees, a significant negative influence of ozone exposure was found. In contrast, no significant ozone effect on diameter increment of beech was detected. The effect of ozone stress on a large spruce tree can lead to a decrease in potential radial increment of 22 %. The results are discussed in relation to other stress factors such as drought and lack of light.

Does Elevated CO2 Protect Grain Yield of Wheat from the Effects of Ozone Stress?

This study has investigated the effects of elevated CO2 and elevated O3, both singly and in combination, on the yield of spring wheat (Triticum aestivum L., cv. Minaret). Plants were grown in open-top chambers and exposed to three CO2 concentrations (ambient, 510 and 680 ppmv) and two O3 concentrations (ambient and ambient +50 or +90 ppbv) either from anthesis onwards or for the full growing season. To date, experiments that have investigated the interactive effects of these gases have shown a variety of responses, ranging from an amelioration of the damaging effects of high O3 to a greater sensitivity to O3 at elevated CO2. The effects on grain yield and yield com ponents were determined. Our results confirm that elevated CO2 provides some protection to a wheat crop against the damaging effects of O3 on grain yield. However, the level of protection varies from one growing season to the next and also appears to be related particularly to the timing of exposure to elevated O3

Ozone stress modulates amine oxidase and lipoxygenase expression in lentil ( Lens culinaris) seedlings

The effect of ozone stress on polyamine metabolism and membrane lipid peroxidation in lentil seedlings through the amine oxidase and lipoxygenase activity and expression has been investigated. Ozone is shown to control the expression of these enzymes at the transcriptional level, down-regulating the amine oxidase gene and up-regulating the lipoxygenase gene. The decrease of amine oxidase activity correlated with the increase of putrescine concentration in the ozone-treated plantlets, whereas the increase of lipoxygenase activity was paralleled by enhanced membrane lipid peroxidation. Finally, polyamines are shown to inhibit lipoxygenase activity in lentils.

Two-dimensional electrophoresis of acidic proteins isolated from ozone-stressed Norway spruce needles (Picea abies L. Karst): separation method and image processing.

The effect of ozone stress (< 10,200 or 400 micrograms m-3) on the protein pattern of Picea abies L. Karst needles was studied by fumigating potted grafts from mature trees. Clonal trees of Norway spruce were fumigated in open-top chambers for one growing season. Proteins, soluble and membrane bound, were extracted from the needles in a four-step procedure: (i) grinding in liquid nitrogen and then in a pH 5.0 buffer with thiourea added to inhibit phenol oxidase and polyvinylpolypyrrolidone (PVP) added to bind phenolic compounds; (ii) precipitation of proteins with acetone at -20 degrees C; (iii) solubilization in a modified lysis buffer; and (iv) dialysis against the modified lysis buffer. Proteins were separated by two-dimensional electrophoresis according to O'Farrell's method. The changes in the silver-stained protein pattern were evaluated by using image processing methods. Electrophoretograms from stressed and nonstressed trees are presented.